Chas Beichman, Exoplanet Astronomer
The search for exoplanets is one of the most exciting and challenging endeavors in observational astronomy. Charles "Chas" Beichman has been a central player in this worldwide effort, from the time when exoplanets were known only as theoretical possibilities, to the discovery of the first, to the current confirmed catalog of 5,000 exoplanets and counting. An expert in infrared astronomy who has mastered the numerous advantages of this observational technique, Beichman splits his responsibilities between the Infrared Processing & Analysis Center (IPAC) at Caltech and the Jet Propulsion Laboratory.
Beichman grew up in Manhattan and completed his undergraduate work at Harvard. At the University of Hawaii, he focused his thesis research on molecular clouds. Beichman came to Caltech as a postdoctoral scholar, and he has made groundbreaking contributions to major observational projects including the Spitzer Telescope and the Infrared Astronomical Satellite. His leadership positions include serving as Executive Director of the NASA Exoplanet Science Institute (NExScI) at Caltech and Chief Scientist for JPL's Astrophysics Directorate. Beyond Caltech, Beichman is deeply involved in astronomy policy and planning, having served as executive secretary of the NRC Astronomy and Astrophysics Survey Committee. His current efforts are centered around the James Webb Telescope and the High-resolution Infrared Spectrograph for Exoplanet Characterization at Keck Observatory.
In recognition of the decades-long timeframe required to bring major new astronomical instruments from concept to operation, Beichman is engaged in planning to ensure that future generations of astronomers will continue to make fundamental discoveries about the universe. And as the technology and resolution capacities of new instruments improve, these discoveries could well yield new insights in the search for life beyond Earth.
DAVID ZIERLER: This is David Zierler, Director of the Caltech Heritage Project. It is Tuesday, December 13th, 2022. I am delighted to be here with Dr. Charles Beichman. Chas, it is great to be with you. Thank you so much for having me in your office.
CHARLES BEICHMAN: A pleasure.
ZIERLER: Would you please tell me your titles and affiliations? I know you have a duality in your work.
BEICHMAN: I am a JPL employee, one of the only ones down at IPAC who is actually at JPL. I'm a JPL Senior Scientist and JPL Fellow. On campus, I have been at various times, going back in the deep mists of time, a postdoc, an IPAC staff member, Director of IPAC, a senior faculty fellow, a visiting faculty member. I'm now a senior faculty associate.
ZIERLER: Since being a postdoc, you have always been here, between JPL and Caltech?
BEICHMAN: That's correct.
ZIERLER: What historically is the connection between JPL and IPAC? How did that get started?
BEICHMAN: I was there at the beginning. IPAC started out—
ZIERLER: What does IPAC stand for, as a starting point?
BEICHMAN: Infrared Processing and Analysis Center. I came as a postdoc in 1979. After two years of working with Bob Leighton, Tom Phillips, and Gerry Neugebauer, I went up to JPL to work on the Infrared Astronomy Satellite, IRAS, of which Gerry was the leader of the U.S. science team. It was at that point a couple of years before launch. I worked on IRAS prior to launch, through its 300 day active period on-orbit, and for many years after the prime mission ended. January 1983 was the launch, so we're coming up to 40 years ago. IRAS produced the first complete and reliable all-sky survey in the infrared, really opening up infrared astronomy in a way that we're now seeing the apotheosis with JWST. First, a sky survey that finds out what you want to go and look at, and then pointed observations go and look at specific targets. We produced a catalog of a quarter of a million objects. That was a big catalog, back in the day.
ZIERLER: Just for perspective, a quarter million was big, then; what is considered big now?
BEICHMAN: The WISE satellite, which IPAC is still operating as the NEOWISE mission, is up to 42 billion measurements of three quarters of a billion objects, so we've moved along quite a bit. But IRAS really revealed the infrared sky as a hugely rich astrophysical environment.
The Capacities of Infrared Astronomy
ZIERLER: What can infrared see that other observational technologies cannot? What makes it so rich?
BEICHMAN: You can see colder objects. You can see further in redshift. You can look through obscuring interstellar dust. These infrared capabilities reveal to you orbiting dust around stars that is the remnant of planet formation, ultra-luminous infrared galaxies at large redshifts. You can see star-forming regions, young stars caught in the process of formation, in a way that was started from the ground. That's how I did my senior thesis and also my PhD work, doing this painstakingly from the ground. We did basically my PhD thesis project in about ten seconds with IRAS. [laughs] IRAS produced this huge cornucopia of data that everyone realized, including NASA, was going to take a lot of time for the community to digest. They decided to have something that we now call Phase E and Phase F on a mission, which are the data reduction and analysis periods, where the project develops new products, and the community goes and works with the data. You build the satellite in Phase C/D; you operate the mission in what's now called Phase E. When the mission ends, you now have something called Phase F, which is a data analysis period, where you have ways for the community that wasn't involved with the mission to access the data in archives that they can work with. IRIS was one of the first missions to really pioneer that concept. The idea of data archives was new. The idea of image processing was new. The idea of scanning through digital lists of sources all were new. IPAC was set up as a way to enable the community, the broad U.S. and indeed the global community, to work with the IRAS data. It was decided to put it onto the Caltech campus because back then, as now, it is easier for visiting scientists, academics, and foreigners, to have access to campus than it is to get into JPL.
ZIERLER: So it was always going to be JPL, but the question was, are you going to house it on JPL or Caltech?
BEICHMAN: It was always going to be NASA-funded.
ZIERLER: So then why JPL? Why not another facility?
BEICHMAN: Because JPL had led the entire mission and did all the data processing. It was a JPL project. It was an Explorer mission that was international, but JPL was the place that built it and made the pipelines that created almost all of the data products, so that within the US, it was always seen as a JPL effort. Gerry Neugebauer was able to push through this idea of having a data center on campus to work with the data. And we've been doing it ever since. [laughs]
ZIERLER: Do you sit here full time? Do you have an office on JPL campus?
BEICHMAN: I do not. I go back and forth. I would say I spend 80% or 90% of my time here. I'll go up to JPL for meetings. Now that everything is Zoomable, I spend more time here than going up there. I don't have an office at the present time, up at JPL.
ZIERLER: Being a JPL Fellow, is that sort of an honorific?
BEICHMAN: Yeah. The more accomplished engineers or scientists are selected by some mysterious cabal of other Fellows up at JPL. That was a couple years ago.
ZIERLER: In terms of reporting structure, who is your boss?
BEICHMAN: I report directly into the Astrophysics Directorate at JPL, so Keyur Patel and Todd Gaier. I also am responsible to Fiona as head of PMA.
ZIERLER: Because IPAC is within PMA?
BEICHMAN: Right. NExScI is a science center that exists adjacent to and within IPAC. IPAC has both specific projects that work within IPAC. It also had the Spitzer Science Center, which was a separate science center, and it had NExScI, the exoplanet center, all of which work under the logistical umbrella of IPAC but also in some cases may have a separate director. Tom Soifer was the director of the Spitzer Science Center. I am director of NExScI. Also I work closely with George Helou, IPAC Director, who has the key role of making sure that IPAC moves forward, both as the home for any science centers it is supporting, but also for all the individual projects it is running. When IPAC was set up, it was only supporting one thing, which was the IRAS data. The idea was it comes down to campus. The deal was campus would pay for a building, the one we are sitting in, one story. The second story came later. Part of that deal was campus would be reimbursed for the cost of building the building by having everybody transition down to become Caltech employees who would then provide the overhead back to campus, making it at least a moneymaking if not at least a break-even venture. After many, many years, I suspect it is money-making.
ZIERLER: In terms of being a faculty associate, if you wanted to, can you teach? Can you sit on graduate committees? Do you have responsibilities at faculty meetings, and those kinds of things?
BEICHMAN: It comes and goes. Certainly, I have access to Keck and so on. I would say the major thing I take advantage of is the privilege to be able to observe at Keck as a Caltech person. Nobody else at IPAC can propose for Keck time. That was one of the perks. I don't have to teach. It's simply a research position. I have worked with graduate students, although in the end, senior faculty associates have to be attached to a faculty member. The great division at Caltech is you're either professorial faculty, or you're not.
ZIERLER: [laughs] That's not the official designation. "Research faculty." [laughs]
ZIERLER: When you say, "attached to faculty," that means you can sit on a committee but you can't direct a thesis?
BEICHMAN: Right. And various other things. If I want to put in a proposal through Caltech, in the end it has to have a professorial faculty member on it. Often, though, I put in my proposals through JPL.
ZIERLER: Just as a way to illustrate how the JPL-Caltech connection is greater than the sum of its individual parts, having this duality to your work, how does it make it more impactful? How are you able to get more done? How is it more interesting for you personally?
BEICHMAN: It's sort of a three-cornered hat that I have. Through JPL, IPAC can be its own FFRDC, but on campus. It can be a NASA center. I can also spin my hat around and be a campus person. I sort of choose which one at any one time is most useful for any one purpose. That's the advantage of it. The disadvantage is that you're sort of betwixt and between the two organizations, and there can be a local minimum of your influence at either place, because you're not sitting really in one place or the other as a fully recognized member. But that's okay—I'm getting stuff done, I have a good time, I get to talk to people. I stopped worrying about that a long time ago.
Current Focus on JWST
ZIERLER: Just as a snapshot in time, what are you working on currently?
BEICHMAN: I have a lot of JWST data, so I'm leading a couple of efforts there. I was on the NIRCam team that built the NIRCam instrument. Of course, it got launched, and it's now working. It has been a long haul.
ZIERLER: Is it NIRCam that is responsible for some of these mind-blowing images we're seeing on social media?
BEICHMAN: Yes, absolutely. There's also the MIRI instrument, which is the Mid-Infrared Instrument, and I helped bring that to JPL as well. With NIRCam, I worked with the University of Arizona group, with whom I had been working with for many, many years, starting with IRAS, then on to Spitzer, and then now onto JWST. I was the node at JPL who got us involved in NIRCam through JPL. I think there's no real campus involvement on that. There's also MIRI, which I helped bring to JPL. We had a competition between Goddard, Ames, and JPL as to who would lead the NASA part of the MIRI instrument. That led to a review at NASA headquarters on September 10th, 2000.—yeah— that September 11th—! I flew out on the last flight from Dulles before—the next day.
ZIERLER: Oh, wow.
BEICHMAN: There were still people in charge on the review board who were there on the 11th; they wound up driving back from Washington to the West Coast. So, that was MIRI. Coming back to setting up IPAC, I came down in transition, like everybody else, to become a campus employee. We were all basically of Caltech staff, with a JPL project manager, and then Gerry or Tom Soifer as the faculty overseer. After a couple of years, I was giving a briefing about IPAC to the JPL director at the time, Lew Allen, who said, "What? This is a JPL effort down there on campus? Who the hell is in charge of that?" I was the director at that point.
BEICHMAN: He said, "So are you a Caltech person or a JPL person?" I said, "Well, I work for Caltech." He says, "No, you don't. By the end of the week, you're going to be a JPL person again." And I was.
ZIERLER: Oh, wow.
BEICHMAN: It took about six months to actually untangle all the benefits and everything else, which had already been screwed up coming from JPL to Caltech, and had to get re-screwed up, to go back to JPL.
ZIERLER: But JPL employees are Caltech employees.
BEICHMAN: They have very different structures for everything. Back then, they were more distinct. There were two very separate HR structures back in the day. They still are quite separate. JPLers have to deal a lot more with the strictures of the JPL contract with NASA. Campus is an educational institution. There are a lot of differences when you get into the nuts and bolts.
ZIERLER: You mentioned Keck, and JWST, of course. With your area of expertise, are you equally at home in both land-based and space-based observational projects?
BEICHMAN: Yes. We're building instruments now for Palomar. I built one of the early infrared cameras for Palomar back in the 1990s. We are now building a spectrometer that is joint between campus and JPL called PARVI, an infrared device that is now the model for an instrument that Dimitri Mawet is building for Keck, called HISPEC. So, yes, I have a long tradition of building stuff on the ground, and then a long tradition of working on stuff in space. I worked on IRAS, not on the hardware but on all of the software helping produce the catalogs and so on.
ZIERLER: Do you have an engineering background? Did you pick up instrument-building along the way?
BEICHMAN: Pretty much picked it up along the way. No one would ask me to build a bridge, but I know enough to ask a lot of questions and work on instruments, not necessarily getting in with the soldering iron, but help on the design, the requirements, work on some software, analyze things, and so on.
ZIERLER: Does your work ever brush up on theory, or you're strictly on the observational and experimental side?
BEICHMAN: Observational and experimental side. Theory is safe from me.
ZIERLER: [laughs] What would you call yourself at the end of the day? Of course, there's astronomy, there's astrophysics, there's cosmology. What discipline would you say is your home?
BEICHMAN: I would say my initial home has been for a long time, and probably still is—as a wavelength person, I'm an infrared astronomer. I bleed infrared. I would say mostly in the last decade I have been doing exoplanets. Starting back in 1995, we started this effort for finding habitable Earths. When I left IPAC, one of my trips where I went back to JPL for a couple of years, I started up what's called the Origins Program, which was NASA's program to figure out, if you look up at that image, how do you find habitable planets? We had missions called the Terrestrial Planet Finder. I was the project scientist for that, within NASA. There was also a mission called the SIM mission, the Space Interferometer Mission, which would do astrometry to find Earths. Then TPF was meant to do the direct imaging version of that. Both of those missions died—cuts, death of a thousand cuts—and eventually went away.
But TPF is coming back. The cronagraphic version of that is now the recommendation of the Decadal Committee for something called—LUVOIR, HabEx were the names of the studies going on. It was then called IR/O/UV for a while—Infrared Ultraviolet Optical Observatory—and now it's being called the Habitable Worlds Observatory. We'll see what it gets called next week. That, after a very long gestation period, is something that, in the late 2030s, might actually achieve this goal of studying and looking for biomarkers on Habitable Zone Earths around solar-type stars. I started that with a small number of people, with Charles Elachi and Neugebauer and a bunch of people, in the mid 1990s. It all really started in the annus mirabilis when the Mars rock and 51 Peg kicked off this whole era of discovering planets, which has been fantastic.
ZIERLER: You mentioned the decadal report, Astro2020. What are some the key takeaways? Where does the field go from here as a result of its recommendations?
BEICHMAN: The biggest one is they're committed to at least a decade of studying whether you can actually build a telescope that will be able to suppress the starlight at visible and maybe near-infrared wavelengths by a factor of a billion to ten billion to reveal the light of an Earth sitting a few hundredths of an arc-second to a tenth of an arc-second away from its host star. Reveal the light, study it, study it spectroscopically to find signs of water, oxygen, and so on. That is what the decadal recommended.
ZIERLER: This is what the TMT will do if it ever gets built?
BEICHMAN: Not TMT. Can't do Earths. This is in space. This is a full-up space mission successor beyond JWST, beyond Roman. This is the next big space thing. The TMT or the European equivalent will not have the sensitivity to work through the atmosphere to do that for stars like the Sun, with planets like the Earth. They will be able, with a lot of luck and hard work, to do that for planets orbiting much cooler M stars, where the contrast ratio between an M star and its planet is more favorable, but the separation between the planet and the star is much smaller. The planet has to huddle up close to stay warm. The space telescopes don't have the angular capability to separate the two, because the space telescope is maybe six to eight meters in size. A 30- to 40-meter telescope doesn't have the sensitivity to do Earth around a Sun, but it could do an Earth around an M star. So there's sort of a—
ZIERLER: What is the difference between a sun and an M star?
BEICHMAN: The Sun is a G star. It's 5,500 degrees C.
ZIERLER: When we say our Sun is a typical sun, we mean a G star?
BEICHMAN: Right, G star, looks yellow, just an everyday star. The much more abundant stars in the galaxy are these M stars, which are much, much cooler. They are 3,500 degrees instead of 5,500. They are a factor of 10 to 100 less luminous. If you want to have a habitable zone, everything moves in much closer.
ZIERLER: The Goldilocks Zone would be where Mercury or Venus is?
BEICHMAN: Yes, in much closer. And that's fine, but if you want to separate the two, you need a much bigger telescope to discern that much smaller angle, because it is huddled in much closer. So, big telescopes on the ground can do M stars. Smaller telescopes in space, but not having to work through an atmosphere, can do G stars.
Technosignatures and Biosignatures
ZIERLER: If you had to guess, decades into the future, would it be more likely that a telescope in space would discover life on an exoplanet, or a telescope here on Earth would, based on the different kinds of planets around these different kinds of stars?
BEICHMAN: That is something we'll find out from JWST. We don't know anything about whether the rocky planets orbiting M stars have atmospheres or not. They are in very close to their star. The stars have a lot of ultraviolet and x-ray activity. They may just be inhospitable places. I would say they are the first places we'll have a good chance to look, and we may come up dry, or we may be totally surprised and they're teeming with life. Could go either way. There, we're just ignorant about what the properties of those planets might be.
ZIERLER: Now, we're talking about biosignatures.
ZIERLER: What about technosignatures, which is obviously even more exciting? Are either of these classes of telescope equipped to look at radio waves or industrial pollution?
BEICHMAN: Technosignatures—people talk about SETI, the search for extraterrestrial intelligence. My phrasing of that is that it's "SETEE"—Search for Extraterrestrial Electrical Engineers. You have to have somebody who is making a signal. That means you have EEs sitting around somewhere. They're either making radio waves, which our radio telescopes might detect, or they're flashing lasers at us which you can imagine detecting. None of the space-borne telescopes are really equipped to do that. We may find systems where there is a good chance of there being a habitable planet. Those may become targets for one of the radio telescopes to go and look at with a lot of attention paid on that one target, rather than trying to survey everything. Similarly, if you want to look for laser flashes, you go and do that. I would say that's a whole different axis of research, and I sort of regard it not as a scientific activity. It's not scientific; it's not not scientific; it's ascientific, in the sense that you have no idea what a negative answer really means.
When you get to the end of the Drake equation—which is one way I sort of encapsulate my career—you go along the different terms. How many stars are there? How many stars that are out there are long-lived enough to be stars where you might expect to have life? How many of those stars have planets? Well, 1995, we didn't know that answer. By now, we have a pretty good idea that a quarter of all G-type stars, or maybe even all M stars, have habitable zone planets. Of those, how many of those have conditions suitable for life? I think we will learn that between the space telescopes and the ground-based telescopes in the next 20 years. How many of those potentially habitable planets have life? We may find biomarkers on one or two of them, so we'll start to get an idea of what that fraction is. That is all about finding, are there planets with pond scum? It's a big step about evolution to get to technically savvy civilizations. It's another step to have those technically savvy civilizations want to talk to anybody. And the most unknown is what is the lifetime of that civilization. All those could be anywhere between zero and one, or who knows how many hundreds or millions of years, which is why technosignatures are such a crapshoot. You've got to look—I've got no argument with looking—but, who knows. One day, we'll find them, we'll hook up to their internet, and all will be revealed.
ZIERLER: From your academic training, was it inevitable for you to go into infrared astronomy, in terms of what you looked at as an undergraduate, as a graduate student, or were you more responding to what was exciting at the time you became a postdoc?
BEICHMAN: It was well before that. I was a philosophy major at Harvard through my junior year. I had always been interested in science and math, so I was taking courses. Then about halfway through my junior year, I decided that where the real excitement was, was instead of studying what is the origin of life, are there other worlds out there, in a philosophical way, studying pre-Socratic philosophers, we actually had the tools to do this, for real. And so, I switched into astronomy. I also thought I'd make more money and meet more girls.
BEICHMAN: As Humphrey Bogart said of the desert, "I was misinformed."
BEICHMAN: About halfway through college, I shifted. My philosophy professors said, "Well, we used to be pretty close, astronomers and philosophers, but that was 500 years ago. Go have fun." Then I started taking astronomy courses at depth. I had one instructor who basically said, "Well, the radio is really exciting, but the place where the action is going to be in the next 20 years is in the infrared." Because it was just starting its ascent, as the technology started to take off. He said, "Go to infrared," and that's really when I started. My senior thesis was doing infrared observations with a guy at Kitt Peak, Mel Dyck, who then went to Hawaii, so I went to Hawaii. I did my senior thesis work with the data from Kitt Peak, working with Mel, Bob Noyes and Ed Purcell, trying to understand polarization of grains, or polarization of starlight by grains, in the infrared, which was really something new at the time. Ed Purcell, who was a Nobel Prize in Physics, couldn't figure out how to align grains. I tried really hard; I couldn't figure it out, either, so I gave up on doing much more polarization work. I figured if Ed couldn't figure it out, I was never going to figure it out.
So, I went to Hawaii and started looking for young stars in the process of formation, which was something being pioneered in the infrared, because you could look through the dust clouds and the clouds of gas and dust in which you thought these systems were forming. The parallel revolution there was people studying the CO molecule, carbon oxide, in the radio, which was work being done at Arizona, UMass, Caltech. Nick Scoville at UMass, Anneila Sargent, a bunch of others, were doing CO work. The idea was to look in the infrared in the cores of these clouds and see if you could find stars that were forming. Neugebauer and Becklin and Soifer had been doing this in places like the Orion Nebula in the late 1960s, early 1970s. The BN Object, the KL Object were all being discovered in the infrared. That's where interest was starting to take off at those wavelengths.
ZIERLER: You mentioned it's really the past ten years where you have been really focused on exoplanets.
ZIERLER: If we were to imagine a pie chart where our sum total knowledge of exoplanets existed, what percentage of that comes directly from infrared astronomy? Does infrared dominate, or is it just one of among many techniques?
BEICHMAN: I would say it's the least of those techniques. The two dominant techniques are actually visible wavelengths—they are the precision radial velocity technique, pioneered by the Swiss group who got the Nobel Prize recently—Didier Queloz and Michel Mayor—and in the U.S., Geoff Marcy and Butler at Keck—together for the first couple of years found the first 400 exoplanets. That was then supplanted by the Kepler satellite when it came along, and the transit technique has since become the most prolific discoverer of planets. What the infrared did, which still remains unique, is two things. One, with IRAS, we found the first evidence for the remnants of planet formation, with these debris disks around stars like Beta Pictoris and so on, where you would see the remnant dust and comets and asteroids out of which planets formed. That started right with IRAS, even preceding the discovery of exoplanets, and led people to go, "There's a lot of solid material out there out of which planets could form." More recently, in the infrared, we've been discovering sort of Jupiter-mass planets orbiting stars at quite large separations, things like Beta Pic and HR 8799. There are a whole suite of planets that have been found by direct imaging using coronagraphs on telescopes like Keck, where you block out the starlight and you look at young planets which are still glowing from their heat of formation. But that's a few dozens of planets, and in fact they're the oddballs. Their orbits are so far out that it's hard to explain why they're there. They're out at hundreds to thousands of astronomical units, whereas the planets of our solar system are at one to ten astronomical units. Most of the planets detected by radial velocity and transits are also in close, but that's partially a selection effect and partially the physics of the formation process. But it's very hard from a theory standpoint to generate planets that far out. They're either ejected, or formed as a clump and a disk, way out there.
So the infrared itself has not done a lot for the discovery of exoplanets. One of the hopes was, with the Terrestrial Planet Finder, that working with an infrared interferometer we would actually be able to null out the starlight, find a planet, and have a major infrared contribution to that. Turns out the more likely path is to do the visible light coronagraph, which is a more traditional way of blocking out the starlight that is more challenging. As I say, it's a billion or ten billion to one, whereas in the infrared, the star is down, the planet is up, the starlight rejection you need is only a million to one. But it's not as interesting for the other astronomers who want to have their telescope for the other 50 to 70% of the time, to have a nice big optical telescope that they can just take over and move around the sky.
ZIERLER: The 5,000 or so that we've discovered already, these are exclusively in the Milky Way?
ZIERLER: We're not talking about exoplanets—
BEICHMAN: The vast majority are within a few hundred parsecs, probably all within 100 parsecs. There is one technique called microlensing, which is a slightly screwy technique based on general relativity, where you have a background star that might be near the center of the galaxy, near the bulge of the galaxy, and an interloper star halfway between happens to go just in front of it, exactly in front of it. When the two line up with our line of sight exactly, the starlight of the background star is bent by the intermediate star, and you get a magnification due to general relativity. If there happens to be a planet in that intervening star, the lens star, then the curve that you get from that simple transit of the lens star against the background star looks like that; if there's a planet, you get an extra little blip. It's like a defect in the lens. Microlensing is actually quite an interesting technique, but it works for very distant planets. They're all tens of thousands of light years away. But with the exception of microlensing, the planets we've found are all close.
ZIERLER: Exoplanets in other galaxies, would it stand to reason that it is basically the same there? That if the Milky Way is not an exceptional galaxy, if and when we get to a technological point where we can think about exoplanets in other galaxies—
BEICHMAN: All the same.
ZIERLER: It would be basically the same?
BEICHMAN: Yes. We're discovering, in the same way that we now know what the distribution of the elements are in terms of carbon, nitrogen, oxygen, in one galaxy is pretty much the same in another galaxy. As you go to earlier times, maybe you get somewhat less metallicity in these galaxies, but we basically understand that distribution of the elements is a fundamental property of the universe.
ZIERLER: Does that affect how we understand the Drake equation at this point?
BEICHMAN: No one has done the cosmological version of the Drake equation, but there's no reason to expect that in a typical, relatively nearby, well-formed galaxy, it is likely to be very different. The physical processes that lead to the formation of stars lead to the formation of a bunch of solid stuff left over from the gas and dust cloud, and that turns into planets.
ZIERLER: The Fermi paradox wouldn't change much as a result, either, I assume?
BEICHMAN: No. If they're in another galaxy, they have to shout louder for us to hear them, travel further for them to get here, and—still tough. So, yes, it all still applies the same way.
ZIERLER: Let's go all the way back to the beginning now. Let's start with your parents. Where are they from and where did you grow up?
BEICHMAN: My father grew up on the Lower East Side of New York.
ZIERLER: Ah, the shtetl!
BEICHMAN: Absolutely. His father came off the boat in 1905, had a dollar in his pocket. He was pickpocketed, he wound up on Ludlow Street, which was where all the people from his village wound up, and he was selling shmatas the next day. His wife came over a couple years later. My father was born in 1913.
ZIERLER: He grew up on the Lower East Side?
ZIERLER: What about your mom?
BEICHMAN: She grew up in Canada. She's Canadian. She was about 20 years younger than him. She was in New York working at the British Information Service, and they just met across a crowded room, and the rest, as they say, is history. She came down through a very distinguished Canadian family. Her early relations were judges or in government, and two of her forebearers were ministers in the government of one of the first prime ministers, Macdonald. He didn't trust either one. One was a drunk, one wasn't a drunk; he didn't know which one he could trust, so the story goes. Her father ran an orchard and a playhouse in the Okanagan Valley up in British Columbia, having come there in 1905 from Winnipeg for his health. My grandfather went to British Columbia for his health on the one side; my grandfather on my father's side went to New York for his health, or at least to escape from Russian pogroms.
ZIERLER: A very different kind of health. [laughs]
BEICHMAN: Different kind of health.
ZIERLER: Your mom came to New York during World War II?
BEICHMAN: Just after. It was 1950 I think, or something like that.
ZIERLER: When did you enter the scene?
ZIERLER: Had your parents remained in the city at that point, or they moved to the suburbs?
BEICHMAN: They were in the city the whole time. I grew up four blocks away from the Rose Planetarium—
BEICHMAN: —which was of course a destination.
ZIERLER: Of course.
From Manhattan to Harvard
BEICHMAN: I'm definitely an Upper West Side boy, until I went off to college.
ZIERLER: What was your father's profession when you were growing up?
BEICHMAN: Newspaper man, labor unions. After his third or fourth newspaper collapsed underneath him in New York, having worked on the Herald Tribune and all of its predecessors and followers, he went back to school, got a PhD in political science. His real focus was the Soviet Union. He was an outspoken anti-Soviet, anti-Communist. When people talk about anti-anti-Communists, he was the anti-Communist they talked about, not liking him.
ZIERLER: So he had very different politics than some of the socialist-minded people in the Lower East Side.
BEICHMAN: Oh, yes. Well, we were big buddies with Irving Kristol and Lionel Trilling and that whole New York intellectual crowd, which, as he said, they started left, and then the Democrats moved to the left, and he stayed right where he was.
ZIERLER: It sounds kind of familiar, in a way.
BEICHMAN: Yes. He was a neocon. It was those days. But he started out going down to Harlan, Kentucky, as a reporter for the Columbia Spectator, and was active in many ways. He was an editor of the left-wing PM newspaper, which was a short-lived exercise in trying to run a newspaper without ads. They soon found out they ran out of money.
BEICHMAN: His throughline was very much New York intellectual.
ZIERLER: Did your mom work at all?
BEICHMAN: Yeah, she taught at the Brearley School in New York. She taught English and philosophy there. Then when I went up to college, he got his PhD and he started teaching up at UMass Boston, so they moved up to Boston. Then she taught at Milton Academy. They lived on the campus of Milton. My brother went to Milton as well. He and I had gone to Trinity School when we were in New York.
ZIERLER: No public schooling for you?
ZIERLER: Is Trinity K through 12?
BEICHMAN: It may be. I was at another school until about seventh grade, Allen-Stevenson, another all-boys school on the East Side. I was a free-range kid. Starting at age 10 or 11, I had a bus pass. I just went out the front door, took the bus over to the East Side. My parents would probably be arrested for that now.
ZIERLER: Were you Jewishly connected at all growing up, members of a synagogue, that kind of thing?
BEICHMAN: No. My father had gotten kicked out of the synagogue at about age 13 for asking too many questions!
BEICHMAN: But culturally there was always an attachment. We would go and visit my grandparents. We'd go to the Lower East Side and pick up the bagels and go to Katz's Deli, or go to Russ & Daughters, where my father had dated one of the daughters at one point. So, there was always a cultural affinity, and my father knew more about Talmud than most people of his age. He was good friends with Herman Wouk, the author. They were at Columbia together. Wouk, who was very Jewish, always said, "There's only person who knows more Talmud than I do." And that was my father.
ZIERLER: Wow! High praise!
BEICHMAN: Yes. He could still speak Yiddish and Hebrew, through the end of his life.
ZIERLER: You must have done very well in high school to get into Harvard.
ZIERLER: Was that the be-all and end-all for you? Did you apply widely?
BEICHMAN: Yes. Harvard, Columbia, Princeton, MIT. I looked at Caltech, and they said in the application form, "How will coming to Caltech help you in your career as a physicist?" or something. I thought, "I don't know."
ZIERLER: Was it physics that you were interested in?
BEICHMAN: No. It wasn't physics; it was, "How would coming to Caltech help you in your career as a scientist?"
ZIERLER: But the default assumption was that you were going to be a scientist.
BEICHMAN: It was not my default.
ZIERLER: No, I'm saying Caltech, that was their—
BEICHMAN: Yeah, it was definitely Caltech's, and it was pretty hard-core. I said, "I'm not ready for that." I got into all those places and just chose Harvard.
ZIERLER: Just doing the math, 1952—you're 18 in 1970. Were you politically engaged at all on campus?
BEICHMAN: No, not particularly. I worked on a paper called The Harvard Independent, which was the antidote to The Crimson.
ZIERLER: I see.
BEICHMAN: I was already a budding little neocon. I liked the counterculture for many of its cultural activities, but not its political ones. Liked the music, still like the music, but did not particularly like the politics, which I thought was nuts then, and is continuing to be nuts to this day. I mean, we're now suffering through the Baby Boomers having—the same arguments that we were having bunch then, a bunch of people with senile dementia are now having on both sides, and it's sort of splitting the country. Still.
ZIERLER: Did you talk to your father about Vietnam, what his views were?
BEICHMAN: Yes. He had been in Vietnam. He was a foreign correspondent, so he had gone there a number of times as a reporter. He had gotten kicked out of all of the press conferences and so on for having reported that after the election, Lyndon Johnson would start the bombing, and that was not well received. He had an article in the New York Herald Tribune called "As the Cookie Crumbles [in Vietnam]." So he had a pretty skeptical view of it, but his view was very much not the countercultural view that we're going in there as imperial warmongers. I think he believed in pushing back the Communists, because that was a real problem, but he also saw that it wasn't working.
ZIERLER: How did you fall into philosophy at Harvard?
BEICHMAN: I like thinking about big questions. "What's the origin of the universe?" And all this stuff. It turned out there was a better way to examine that than thinking the world was on the back of a tortoise.
ZIERLER: Was there a class or a professor that made you make the switch?
BEICHMAN: I had had a professor in high school who was both the philosophy teacher and the physics professor, and he was very inspirational.
ZIERLER: Do you remember his name?
BEICHMAN: Yes, Sorel Paskin. He was at Trinity, and I worked pretty closely with him. He taught geometry, then physics, then philosophy. It was very much an outgrowth of having worked with him that I had these interests in both camps. Then just the dramatic growth in physics starting at the beginning of the 20th century and explaining everything through quantum mechanics, relativity, general relativity, and so on. Then the philosophical implication of that, quantum mechanics—it was all very fascinating.
ZIERLER: Was Purcell your key professor in physics as an undergraduate?
BEICHMAN: He was certainly one of them, yes. There were a couple of others. He was in the Physics Department, so I went down to him for help on this one particular astronomy project that I had, because he had written some of the seminal articles on the physics of how you align dust grains to make polarization that we were finding in the infrared. I had also worked with Giovanni Fazio, who was later the principal investigator on one of the Spitzer instruments. He had a project to put an infrared telescope on a balloon and fly that and make measurements above a lot of the atmosphere. That kept dragging on, and dragging on, and dragging on, as balloon projects do, and it wasn't really good for the time horizon of getting a senior thesis done, so I shifted to doing a ground-based project. But I had worked with Giovanni, and Bob Noyes, and a bunch of other people up in the Astronomy Department, then Ed for this one project down in the Physics Department.
ZIERLER: Your degree was in Astronomy?
ZIERLER: Do you have a clear memory of when you decided to stick with it and go to graduate school?
BEICHMAN: When you start pursuing an undergraduate degree in astronomy, there's not much else to do other than—
ZIERLER: Keep going?
BEICHMAN: —keep going.
ZIERLER: In 1973, when you graduated—
BEICHMAN: I was about a year young.
ZIERLER: Oh. Had you skipped a grade?
BEICHMAN: I just started early. My parents put me into a kindergarten when I was three or four. They just figured, "Yeah, you can go to school." I was in a French school. It was half in French, half in English. I hated it. But I learned French, which turned out to be very valuable later on. So, I was always a year ahead.
ZIERLER: In 1973, then, was the draft something you needed to contend with?
ZIERLER: Okay. Nice and high number.
BEICHMAN: That was my lottery number. Also things were winding down at that point.
ZIERLER: Where had you considered for graduate school? What advice might you have gotten?
BEICHMAN: Having started late, I did not have a fabulous academic record at the time. I had applied a couple of places, the usual East Coasty places, didn't get in. Got into Hawaii. Had never heard of Hawaii. In the immortal words of I forget who it was, who asked, "What was Pearl Harbor doing in the middle of the Pacific Ocean?"
BEICHMAN: My idea of Hawaii was Don Ho, if that. But it was a place where they were doing infrared. The guy I had worked with at Kitt Peak, Mel Dyck, was going there.
ZIERLER: When had you gone to Kitt Peak? A summer?
BEICHMAN: That was the summer of 1972. That was my senior thesis topic.
ZIERLER: What was that like, being at Kitt Peak?
BEICHMAN: Oh, it was fun. It was my first time observing through a telescope. Having grown up in New York City, I never saw a telescope. I worked with Mel that summer at Kitt Peak, and that was the data that became my senior thesis at Harvard. Then I just continued and said, "Well, let's go to Hawaii. Mel is going there. I'll go work there." So, that was graduate school.
ZIERLER: It must have been an adventure for you.
BEICHMAN: Oh, yeah. It was different in every possible way. The intellectual climate was less rigorous. The physical climate was fabulous. I did a lot of body surfing. It was great.
ZIERLER: Did Mel remain your thesis advisor?
BEICHMAN: For a couple of years. Then I shifted over—in fact, Eric Becklin, who was Gerry's postdoc—
BEICHMAN: —Neugebauer—went from Caltech to Hawaii, and I hooked up with Eric, and so he became my actual thesis advisor. I finished off my thesis with him, and he said, "Well, you should go to Pasadena, and be a postdoc with Gerry and Bob Leighton"—and Tom Phillips, who I had met separately.
ZIERLER: R.I.P. Recently passed.
BEICHMAN: R.I.P, absolutely. I worked closely with Tom for the first couple of years when I was here. I was then a postdoc. Definitely Eric arriving in Hawaii made a big difference that vectored me to Caltech. The rest, as they say, is history.
ZIERLER: What did you work on for your thesis at Hawaii?
BEICHMAN: Looking in the cores of these molecular clouds. Scanning a telescope up and down, with a one-by-one array detector, which was basically a single element detector array, like looking through a soda straw, one spot at a time.
ZIERLER: That's why it took so long.
BEICHMAN: That's why it took so long. You'd map out this little tiny region that would be centered on the molecular cloud peak that the people studying the millimeter CO data would say, "Oh, there's a molecular cloud here, and here's the densest part of it. Go look there." So, I would do that.
ZIERLER: What were the key conclusions of your thesis?
BEICHMAN: The cores of these molecular clouds have protostars that are forming. These were still big massive stars, not regular stars like our Sun, ones that are two, three, and five times more massive, and hundreds or thousands of times more luminous, because that's all we could detect at the time. These were big massive molecular clouds, thousands of solar masses worth of gas and dust, and they'd have, right at their core, a big, fat protostar in the process of formation.
ZIERLER: The observational work you could do right in Hawaii, or you had to travel for this?
BEICHMAN: I had to go to Mauna Kea.
ZIERLER: Mauna Kea!
BEICHMAN: Yeah. That's the beginning of my career with Mauna Kea, when there were three telescopes up there. UH had an 88-inch, and a 24-inch, and then the Air Force had another 24-inch telescope. I would sit in the freezing cold with no oxygen scanning these little regions with the 24-inch. Then, if we found anything interesting, we'd go up to the 88-inch telescope and do more of that.
ZIERLER: Just to foreshadow to all of the political tensions and difficulties with Mauna Kea and the TMT, did you have any sense at the time if the native peoples of Hawaii were upset or felt excluded? Was that on your radar at all?
BEICHMAN: No. I would say
, this was not on anybody's radar at all. In my interactions with the local people, which was mostly restricted to the people who working at the Observatory, there was no broadly public sense that this was a sacred mountain at that time. That came up much later as into the public consciousness—
BEICHMAN: Far be it for me to say.
ZIERLER: But at that time, there was no indication?
BEICHMAN: It did not appear to me to exist. More telescopes got built. Everybody liked the jobs. Everybody liked the construction work. Everybody was very happy with it. I think the wokeness, if we will, didn't come until much later.
ZIERLER: Yes, and there's a generational aspect to that as well.
BEICHMAN: Yeah, it's generational, it's political, it's religious, or the recovering of an older religion. There was a lot that came later, and I don't have the knowledge to speak about was it always there simmering or was it invented later, by people harkening back to a time they wish was still there. I'm sure there are always people who were somewhat upset about statehood and so on, but that was really not in the front of anybody's minds at that point, as far as I know.
Arrival at Caltech
ZIERLER: What year did you arrive in Pasadena?
ZIERLER: Your initial appointment was as a Caltech postdoc?
BEICHMAN: Caltech postdoc.
ZIERLER: No JPL affiliation.
BEICHMAN: Right. That happened at the end of my postdoc, end of two and a half or three years. The construction of IRAS was wrapping up and launch was only a year or two away. Gerry and Tom Soifer said, "We've got a position for you up there. This is going to be exciting." I said, "It'll be exciting." And it was.
ZIERLER: Were you exclusively in Neugebauer's group? Were you working with Tom as well, at that point?
BEICHMAN: Both. I did some flights on the C-141. One of the things I was early doing was working for Leighton on what later became the CSO. My major contribution was to slow down the project by five years by telling them they'd better have a dome for this thing.
ZIERLER: Why did it need a dome?
BEICHMAN: Because with 150-mile-an-hour winds, and blowing sleet and snow and so on, which was the sort of thing that could happen up there, if you didn't have a dome, you would have a lot of problems with this telescope. They realized, "Gee, maybe we should have a dome," which complicated just taking one of the dishes from Owens Valley and just driving it up in a truck. So it became a much more complicated thing. That slowed it down enough that I really shifted off from that, and worked then more closely with Tom and Gerry and Tom Soifer.
ZIERLER: I have had the pleasure of meeting Tom Soifer, of course not Gerry. What was Neugebauer like as a person?
BEICHMAN: I would say a bark that was mostly worse than his bite, but if you needed to get bit, he would certainly bite.
ZIERLER: He was intense?
BEICHMAN: Very intense. Very rigorous. There are a couple of anecdotes, and I would say adages—that when you write a paper, get the data right. Nobody cares what your theories are or what your interpretations are, but the data better be correct. He used to talk about drawing half-VAST conclusions coming from half-assed data, which was something to be avoided. But, get the data right, and after that, make something up. He was very much an observational person who really cared about getting the data correctly.
ZIERLER: What was he focused on at that point, when you connected?
BEICHMAN: Infrared to everything. He was one of these four or five pioneers of infrared in the world, in the country.
ZIERLER: Was he a builder as well? Did he actually work on the instruments?
BEICHMAN: Oh, yeah. In the physics department in Downs, which was where all the infrared astronomers were, not in what was the Robinson Building, which is where the optical astronomers were. These were two completely different universes, the requirement there for your PhD is you had to build something. Every PhD student had to build some instrument, some experiment, to get it done. So it was very much an observational and instrumentation group. The list of people who came out of that group, they're everywhere in astronomy now. Eric Becklin went on to Hawaii, UCLA and the Director of the SOFIA Observatory. Tom Soifer stayed at Caltech to become director of the Spitzer Science Center. France Córdova was in the x-ray side of Downs but went on to her career, and as head of NSF. People just went everywhere with the skills and the passion that came out of Gary's group.
One IRAS example of how important he regarded getting the data right is we were just doing the final calibrations, and we had this issue that—getting the brightness of the sky was a careful calibration process. You'd put in a number that the brightness of the sky, right at the North Pole—you'd put it in, and it had to be 1.000, and the data processing should go through that. This was sort of a test, and you want to make sure that at the end of all that processing, you got the brightness to be 1.000 again, because that's what you put in, and you ought to get it back when you came back around again. And it came out different. It came out to be 1.1. Just a 10% effect. Well, you know, "No. That can't be right." It turned out there was a whole question of how you calibrated one of the resistors in the signal chain, and that the brighter the sky was, and as you went to the very bright parts at the center of the galaxy, that became a non-linear effect. So, that effect that was a 10% here was like a 50% over the rest of the sky, which would have been a disaster. Gerry said, "We're not putting this out until we get that right." So we kept hammering on it until we found out, "Oh, you have to change this load resistor curve, and get it right." And, we got it right.
ZIERLER: Tell me about how you got seconded to JPL. How far into your postdoc did that happen?
BEICHMAN: Oh, that was the end of my postdoc. I then became a JPL scientist. It was in my second-and-a-half or third year. The postdoc was ending, I needed a place to go, and JPL was a logical place.
ZIERLER: Was that one option among many? Did you look at professorial positions at all?
BEICHMAN: Not particularly. It just came up, and—
ZIERLER: It was natural?
BEICHMAN: "Space satellite? Wow. That'll be fun." It just seemed like a natural progression to stay inside Pasadena.
ZIERLER: This origin story of IPAC, JPL, Caltech, was this already in train at that point?
BEICHMAN: No, we were still hoping the damn thing would work. There were many doubts that it would not work, including to the Friday before the launch—which might have been a Monday, maybe?—we had the final launch readiness review, and the chief engineer of NASA, who was chairing the review board, Hans Mark, decided at the end of review that this satellite should not be launched, the spacecraft was not ready, and it should be sent back to JPL, and various things should be fixed. He recommended not launching. At that point, the head of JPL, Lew Allen, and the project manager, Gerry Smith, who was project manager later on of Keck, said, "No, this is as good as this thing is ever going to get. If you take it off the rocket"—it was already on the rocket—"you should just take it to the Smithsonian, because we're not taking it back to JPL. Let's launch it." And they did.
ZIERLER: Wow. Did you see that as risky?
BEICHMAN: Yeah. [laughs] Well, they knew more about it than anything else. The risk was, there were just so many things that were going to get worse rather than better. There were these valves inside the cryostat that was housing the helium that you could hear them grinding every time you turned the valve, and if one of those valves broke, you'd have to completely disassemble this whole satellite. You'd wind up running out of money and NASA would have just cancelled the thing. It never would have launched if they hadn't launched it then. It was the peak of readiness. There was maybe a 10% chance it wouldn't go, or a 20% chance, or it might have just worked, and at that point, this was as ready as anyone could make it, with dollars and resources available. JPL pushed through and said, "Push the button."
ZIERLER: What year did you start at JPL?
BEICHMAN: That would have been 1982, I guess.
ZIERLER: Just for the chronology, when they actually pushed the button, what year is that?
BEICHMAN: That was January 1983, so I would have been there about a year.
ZIERLER: Was that your project? Was that what you were working on?
BEICHMAN: That was what I was working on, yes, and for the next couple of years after that, as well.
ZIERLER: What happens as a result, after this thing is launched?
BEICHMAN: The cover comes off, and we see the infrared sky for the first time! So, this is the tracing—
ZIERLER: Oh, wow.
BEICHMAN: —of the cover coming off after a couple of days in orbit. There were some various problems getting it to actually respond to the ground and making it work, so we didn't know if it was going to work, or not going to work, but it did. The cover comes off and you can see the infrared detectors actually seeing the cover float away, and then you start seeing the infrared sky. That first little bump, Fred Gillett, one of scientists, noted, "Oh, that's probably an infrared galaxy." So, it all worked, and the result was—as you walk down the hallway, you probably—I don't think I have an IRAS picture here, but down the hallway, you'll see these all-sky images, and really the first of those was finding this quarter of a million objects and opening the infrared sky with galaxies, debris disk dust, and all those things.
ZIERLER: So the idea of "seeing the infrared sky," you're literally seeing things that could not be seen otherwise?
BEICHMAN: Right. The atmosphere completely blocks it. The whole point of going into space in the infrared is threefold. If you go into space, you can cool down your telescope so that the heat from your telescope doesn't interfere with your ability to see the heat from the objects in the sky. You have no atmosphere, and the atmosphere is either emitting radiation itself, because anything that is room temperature is glowing in the infrared, or it's absorbing all the radiation. The problem with global warming is our atmosphere lets sunlight in and traps infrared radiation as a greenhouse. That absorption means there are whole swaths of wavelengths that you can't see the sky through. In windows where you can sort of look out through a translucent window, the atmosphere is also glowing. All those things make you want to go into space. When your cover comes off, the background against which you're trying to find sources decreases by a factor of one million.
ZIERLER: Phew! Which allows what?
BEICHMAN: An observation that takes one year on the ground, which means you'd never make it, takes 30 seconds. You just can't beat it with a stick. It's just fantastic. It just opens up a complete new way of looking at the world that you could never have if you were stuck on the ground.
ZIERLER: If this thing failed, would that have been the end, in terms of as a proof of concept? Would there not have been appetite to try again, do you think?
BEICHMAN: The attraction would still have been so great that someone else would have tried. The Europeans had a mission that they were pursuing called the Infrared Space Observatory. The attraction of that factor of a million improvement in sensitivity would have still dragged people along. But it certainly would have been a huge setback. We demonstrated a whole suite of technologies—cold telescope, flying liquid helium in space. All sorts of things were demonstrated by IRAS that then became the baseline for the European ISO satellite and for the Spitzer satellite that followed. All of those came out of IRAS, which both found that the infrared sky was interesting, found objects that were interesting to look at, and demonstrated that this factor of a million was real, and demonstrated a lot of the technologies. So, yes, it was I think a very consequential mission.
Discovering Star Formation
ZIERLER: In broad terms, as a result of the launch, what did we learn about the universe? What did we see that we couldn't see before?
BEICHMAN: Stars like our own Sun, not just like these big massive stars, forming in these little dust clouds. We learned about how stars like our Sun form. We learned that many of them had this solid matter also around them that was the remnant of the star formation process that was really the remnant of the planet formation process. It's a big hint that there are probably planets out there, without directly detecting planets. As you move further out, you learn that you have these ultra-luminous infrared galaxies that are galaxies colliding with each other, and that's a huge source of energy in the universe. You're finding black holes in the center of galaxies that are powering other very luminous galaxies. You start looking for the clustering of galaxies, which is now a very big topic of cosmology where you look at galaxy clusters and say, "How does this relate back to dark matter?" and so on.
The first decent catalog you could do that with was the IRAS catalog, because the previous galaxy catalogs in the optical were hindered by the fact that you get so much dust as you go down towards the plane of the galaxy, you can't really use galaxy counts, because they're so contaminated by the fact that as you go lower and lower down, the galaxies just start disappearing. You can't count the galaxies very well. Infrared doesn't care about that dust; you see right through it. So, people used the IRAS catalog as one of the first ways to look at galaxy clustering. That then taught us more about how galaxies themselves start to form. So, there were a whole suite of things that just got opened up that then get expanded upon as Spitzer comes along—first what's called SIRTF and then called Spitzer. One of the things we had done is we wanted to position IPAC to be the home for the analysis, first for doing the hardware of Spitzer itself—and that was a competition between Goddard and us—and then where would the science be. The science center, we wanted to make sure IPAC would be that science center. I was director at that point. I became director pretty much as IRAS's Phase F was rolling off, so we had to find something new to do. NASA was pulling back the money, and we went from about 60 or 70 people down to about 30 people. That wasn't fun.
ZIERLER: What year was this?
BEICHMAN: This would have been, I would say, early 1990s.
ZIERLER: This is the general contraction of the space budget.
BEICHMAN: IRAS is over. Time to move on. I had been back at Princeton for two years on a sabbatical, working on the 1990 decadal report with John Bahcall, which is the decadal that recommended that SIRTF be the number one recommendation, and also what is now the SOFIA Observatory was the second recommendation. That proved to be a disaster --we can talk about that. But Spitzer was great. I came back to be director as IRAS was ramping down and we needed something to do, to keep us alive, to be positioned to become the Spitzer science center. So, we started something called the Two Micron All-Sky Survey, 2MASS, which was a ground-based effort, two telescopes north and south, where we worked with the University of Massachusetts to put together this sky survey that was really the first ground-based sky survey that was a digital survey that produced over 450 million objects. No one had really done a good digital sky survey before, including the optical astronomers who were hopeless at this sort of thing. They had done a photographic survey from Palomar, but never just a decent sky survey. So, we put that together. We did all the data processing for that. That built on our strength from doing the IRAS processing. We also got involved with the Europeans' ISO mission, which proceeded Spitzer by five or six years, and so we worked with them. That showed that we still had the chops to operate a space mission. I made sure we had both space activities, ground-based activities, so that when it came time to decide where to put the science center for Spitzer, we were the logical place.
ZIERLER: You can go either way.
BEICHMAN: We could do both. We could do the work to process lots of data, but you could work with the community and handle tools and work with the general investigator community, which are the two roles you have to have to operate a space observatory science center. Then the choice was made to put the Spitzer Science Center here.
ZIERLER: You mentioned SOFIA was a disaster. What happened?
BEICHMAN: It was 20 years too late. It had a time. If it had flown—actually, the selection of SOFIA goes back—I was on an advisory committee to NASA along with Martin Harwit, whose name you may know, a Cornell astronomer, early pioneer, head of the Air and Space Museum eventually. Martin and I were chairing this committee, what to do next in infrared astronomy. The SOFIA project came in and said, "Well, we're going to get a free 747 from Pan Am. We'll get a free telescope from Germany. We'll shut down the Kuiper Observatory and use that money to cut a hole in the side of the airplane from a chop shop in Tijuana, and we'll fly it 100 nights a year, and it will basically be free." Then there were a couple of other alternatives. Giovanni Fazio wanted a bigger balloon telescope, and so on. But SOFIA sounded terrific, so we recommended that. Then it was recommended to the decadal committee and I and the others were sitting there and said, "Well, this sounds like a deal."
It would have been a good thing. You get above most of the atmosphere. There's wavelengths that are accessible for the first time. It's not as good as going to space, but if you're not yet in space, this is a good thing. But it dragged on, and it dragged on, and NASA came up with some fairly crazy ideas of how to operate it. We'd let United Airlines run the thing, and the cost kept escalating, and it kept taking longer and longer and longer. Meanwhile, the Europeans launched the Herschel Space Observatory, which operated in the same wavelengths, above the atmosphere completely, which was better. It operated 24/7, 365 days a year, which is much better than the 20 or 30 flights a year that SOFIA was going to, in the end, be capable of, after Herschel had already finished its mission. There was nothing left for SOFIA to do. It was a good idea, but it was overtaken by events.
The Search for Exoplanets
ZIERLER: When Spitzer was up and running, was that the totality of work you were doing at that point?
BEICHMAN: No, I had shifted off of Spitzer. They spun up the Spitzer Science Center. Tom became its director, and I went back up to JPL to start this whole Origins program for exoplanets.
ZIERLER: Would that have preceded the discovery of the first one in the mid 1990s?
BEICHMAN: It was sort of simultaneous…the whole idea of exoplanets was just starting to gather steam. A person who does not get enough credit for that is Dan Goldin, who as NASA administrator really said, "How did we sell NASA for 30 years? It was a picture of an Earth. Our Earth. A pale blue dot. I want to do this with other planets."
ZIERLER: Oh, wow.
BEICHMAN: He had some pretty wacky ideas. He wanted to get that picture itself, around a nearby star. That was tough. That's still tough. But the idea of detecting planets and detecting life, he really pulled it along, and I think he just sensed that the ability to start finding planets was just about to happen. That's when the first radial velocity planets started to come, and the whole thing just took off, very synergistically, with NASA being interested, the ground-based community starting to make the breakthroughs, that all of a sudden it was easy to start finding these planets. Mayor and Queloz found 51 Peg, because they said, "How could you have this oscillating thing on a four-day period? Wait a minute. I could actually put a four-day sine wave through this." Even though you expect the Jupiters to be way out here, with very loooooong, slow radial velocity oscillations, all of a sudden, you go, "Oh my god, they're hot Jupiters. They're in a four-day orbit. That's not noise. That's no Moon. That's no noise. That's a planet."
ZIERLER: To go back to this very important point you made about the infrared sky opening up and at least theoretically it became clear that there might be planets there, is that to say that prior to the dawn of infrared astronomy, you could make the case that potentially our solar system was truly unique, that there might not actually be other planets out there?
BEICHMAN: Yes, one of the revolutions that was brought about by the infrared and the millimeter was a much better understanding of how stars and thus planets actually form. That there is this collapse of gas and dust, and maybe it's rotating because there is some angular momentum, you get flattening into a disk, that disk funnels material into the central star, the star forms, you start seeing the material getting blown away, and you get all of a sudden, lo and behold revealed, a young star, and this leftover debris. That really set us on the path of thinking, "Well, if that's how stars really form, that must be how planets form." We see that this is the way that all stars form. We see lots of these systems with leftover stuff. Planet formation must be common.
There were competing theories of planet formation, that you'd have two stars that would have a near collision, and one would be just grazing by the other, and that would pull material off the first star, and it would just form like little droplets, and that material would somehow magically turn into the planets. Very rare. There were certainly arguments that planets could be a very rare outcome of whatever the mysterious process of star formation was. I think a major contribution of infrared and millimeter astronomy was to put that theory aside and say, "This is the way stars form. Solid material is there. You're going to have the stuff of planets everywhere," so that when the mid 1990s come along and people start detecting planets, everyone is ready for that to happen.
ZIERLER: Administratively, what was the process like, getting Origins up and running?
BEICHMAN: Dan Goldin wanted it, and Charles Elachi was very enthusiastic about it.
ZIERLER: What was his position prior to being director?
BEICHMAN: He was head of the—there was sort of a combination of astronomy—just a lot of the instrumentation observing work was under Charles. I forget the name of the organization at that point, but an awful lot of the things that were instruments leading to spacecraft of various sorts. I think really the Earth—anything down-looking or outward-looking that wasn't landing on something was his bailiwick, and maybe even some of the instruments that went on the things that landed on things was in his bailiwick. So, he was very excited about this, and wanted to push Spitzer. Spitzer had been languishing. At some point, even though the decadal had recommended it, Congress had said, "No, we're not interested." In fact, Spitzer, then called SIRTF, was written into law that you should never say the word "SIRTF" again. It was outlawed.
People didn't give up. We actually had an infrared telescope test bed technology program that built the 85-centimeter beryllium mirror that became the SIRFT mirror, when all of a sudden during the annus mirabilis, OMB came in, and the White House said, "We really like this stuff." The Mars rock turned out to be not a sign of life. But the planets turned out to be planets. OMB came to NASA and NSF and said, "What do you want to do?" Wes Huntress walked in along with his NSF counterpart, and Wes said, "Here's our ideas. We want to get Spitzer going, SIRTF going. We want to build a space interferometer mission." That was already recommended by the decadal. It would also find Earths. We wanted to start TPF. And we wanted to start thinking about a successor to Hubble later to be called James Webb. And, you know, two out of four ain't bad!
BEICHMAN: All those started going, and all of a sudden Spitzer, which had been like an airplane sitting at the gate, taxiing out, being brought back to the gate, taxiing out, being brought back to the gate, all of a sudden it was on the runway taking off. So, Spitzer happened very quickly, all under the umbrella of Origins. The astrophysics budget had been going down, and all of a sudden, with the Mars rock and planets, the budget started going up and all these things started happening again.
ZIERLER: Where was Ed Stone in all of this, as JPL director? Was he engaged?
BEICHMAN: Yeah, I think so. He was more interested in the planetary side of things, but he was certainty encouraging all of this. I think Charles really had the energy on some of these specific areas that I would see, but Ed was certainly very supportive of all of this.
ZIERLER: Administratively, what programs were under Origins? What projects were part of its entirety?
BEICHMAN: Spitzer got spun off very quickly because it became a flight project.
ZIERLER: As opposed to what? What would it have been?
BEICHMAN: Pre-formulation, studying—you do studies, you formulate, you go through Phase A until a mission has enough definition that it actually gets far enough along that someone says, "Okay, you are now a real project. Somebody go and build it." We were doing the SIM project, and the TPF, some of the ground-based work—the Keck interferometer. Another disaster. It was a great project, but it just suffered from all—that's where the first problems that now face TMT started to raise themselves. There were simply at that point too many telescopes, and there was a nascent sense of—
BEICHMAN: Yes. We were supposed to have both the two Kecks, as an interferometer linked together, and four outrigger telescopes, and it was getting the permits for those telescopes that dragged on forever, due to the worries about—it was more about conservation than the religious and political things that are now, that are the sense of grievance. But there was the wekiu bug, and just upsetting the environment on the summit. The Keck interferometer did spectacularly and would have been a great facility going forward, as we're now seeing with the Very Large Telescope Interferometer that the Europeans are doing fabulous things with. We were there 20 years ago. But, ‘twas not to be.
Five Thousand and Counting
ZIERLER: Do you have a clear memory of when that first exoplanet was discovered?
BEICHMAN: Oh, yes. Absolutely.
ZIERLER: Was there a concern that it would have been an anomaly, that we found one but we would not find others? The other way of looking at it is, if you find one, definitely that means there's a whole world of them out there.
BEICHMAN: There were certainly some people who argued that the first couple of radial velocity planets weren't even planets. The radial velocity signature depends on the orientation of the system. If the system is edge-on to you, you see the full Doppler motion back and forth. If it's face-on, like this, there is no radial velocity component. If that whole motion is this way, or this way, of the planet going around, and it's tugging its star in the plane of the sky, none of that motion is directed towards you. If you're finding a radial velocity signature of a system that is really like this, the mass you're measuring is the mass times the sine of that angle. If you have to correct it for being almost face-on, it takes a much bigger mass to give you a signal for a face-on case than an edge-on case. You could argue these things you think are a Jupiter mass, edge-on, could actually be a very low-mass star seen nearly face-on. So, there were people who were arguing for a couple of years that, "Nah, you're not really seeing planets. They're just a few squirrely cases that are like this." As more of them started to occur, you start seeing more and more of these radial velocity detections, it becomes harder to maintain that argument that this is a very rare occurrence of things that are really low-mass stars seen face-on and not planets at some more average angle.
What actually—and it's a nice example of how science works—what cemented the interpretation that these are planets is eventually, some system will be oriented in such a way that not only is it not face-on, not only is it some angle to you, but it is exactly edge-on. If it's exactly edge-on and you look at the right time, you should see the planet go in front of the star. It should transit. So, when the first planet came along that was a radial velocity planet, where we knew the ephemeris well enough—and Geoff Marcy and David Charbonneau were both doing this simultaneously and independently—discovered that two of the in-close hot Jupiters transited their host star, you immediately got rid of this argument that, "Well, it could be a face-on thing," or something. You knew it was edge-on. At that point, the ambiguity of the sine of the inclination angle went away. I hold this up as a great example of how science works. You discover something with one technique, and then you come in with a completely different technique, make a prediction, confirm it, and learn ever so much more.
ZIERLER: Is that the big story of how we got from that first discovery to 5,000 and counting now?
BEICHMAN: Yes. In fact, the transit started out as looking at the systems that had radial velocity planets, because that's where you could look, but the odds are low. If you're doing it star by star, the odds of any one RV planet being aligned just carefully like that is 10% if you're in super close in a four-day orbit, and quickly goes to 1% if you're further out. So, any one RV planet, pretty unlikely that it's going to transit. The secret, and this is what Bill Borucki struggled for many years to make happen, is survey 100,000 stars, or 50,000 stars, and—worked great.
ZIERLER: It's like a blunt-force approach? You just look at as many as you can? That's the basic idea?
BEICHMAN: Yeah. And it took a long time before the technology with CCDs, detectors, being in space where you could get the precision and just stare, uninterruptedly, for three years, and you'd see the little dips.
ZIERLER: I lost in the chronology going back and forth between Caltech and JPL. By the early 2000s, where are you at this point? Are you going back and forth? Are you more at one than the other?
BEICHMAN: I was pretty much solidly up at JPL for about ten years, and then I came back down here—I'd have to check—2003 or something like that. We had started the science center here for the Space Interferometer Mission, SIM, and that was just starting to gear up. At that point, I went back up to JPL to do more of this Origins work, so Anneila Sargent took over as head of what was then called the Interferometer Science Center, because she had the interferometer experience. That was going to be the science center for the Space Interferometer Mission. She was heading that up for a couple of years. Then it became obvious SIM wasn't going to happen.
ZIERLER: Why not? What happened?
BEICHMAN: It too was overtaken by events. It was run over by two things. First, the radial velocity technique kept getting better. Astrometry does not have this problem of edge-on versus face-on. You'll always see the motion. If it's face-on like this, you'll see the star going up, down, left, right. If it's edge-on, you'll see it going this way. Radial velocities has the problem that the stars themselves are very noisy, when you try to match up the spectral lines to see the wobbles, whereas astrometry doesn't have that problem, or much, much less, so it had the promise of actually getting down to finding Earths in the habitable zone of our own Sun. That's the key thing of finding Earths in the habitable zone around stars like the Sun. Technologically very challenging, and the RV guys kept coming down, better and better and better, never getting to quite that level—they probably never will—but that took away some of the science goals of SIM. The Europeans were going to do an astrometry mission that would do the whole sky, another of these sky surveys, and do hundreds of millions of objects.
ZIERLER: When we say whole-sky, we mean northern and southern hemisphere?
BEICHMAN: Everything, yeah. Whereas SIM was going to be like a real precision set of calipers to do this star, then that star, then this star, then that star. And it would do some interesting astrophysics, but its real focus was to do 100 or 200 stars, to find the Earths. It didn't have enough general astrophysics for the rest of the community. Developed a lot of great technology and had been recommended by the 1990 Bahcall report, had been endorsed by the 2000 decadal report, and was killed in a footnote by the 2010 decadal report, which really wanted—the other overtaken-by-events steamroller was wanting James Webb. They wanted nothing in the way of James Webb, which was going to be another Hubble to feed the masses with great data. It did, it does, and I said, "Good, I'm going to be on James Webb, too."
ZIERLER: Were you involved in the 2010 decadal?
BEICHMAN: No. Well, we were actually presenting. We were presenting SIM and TPF, so I was on the other side of the table.
ZIERLER: When did James Webb start to feel real for you, that it was actually going to happen? It has such a long back story.
BEICHMAN: Yes, it goes back a long way. We put in a proposal back in 2002 or something like that, to be the camera that would be selected, and then we were. Then there was an awful lot of this you're in the airplane, you're at the gate, you get on, you taxi around, you come back, you go back and forth. Then slowly but surely, it started to gather steam. But the costs were going up, it was getting delayed, and it was nip and tuck. But the science community really wanted it, and the science potential was so great that it would have been really hard to cancel it. It was hard to get it done and push it through, but in the end, it was—as we said, it was right-sized. But it was sold as a fantasy. Dan Goldin—it was originally going to cost $500 million, which is essentially less than what Spitzer cost, and then it was a billion dollars, and then it was $3 billion, and now it's $9 billion. That has left a sour taste, I think, at places like OMB, so things like the next big decadal recommendation for this new Habitable Worlds Observer, which the initial cost is $11 billion, is going to be a tough sell.
ZIERLER: Right, because it's really going to be $20 billion.
BEICHMAN: First it's going to be 11, which they don't like, and then they're suspicious that it will actually be much, much bigger than that. So there's a lot of pushback. I'm not sure—it will take a while.
ZIERLER: Dan Goldin's forward-looking dream of photographing another Earth-like planet, was that part of the appeal, that the James Webb would be able to do that?
BEICHMAN: No, that was really the appeal for SIM and TPF. He really wanted to focus on the dot. But, he also liked James Webb, that it would be a step along the way, just because a big infrared telescope in space was a good thing. What Dan provided was an impetus for a big telescope, because he wanted NASA to play at the big boys' table in Washington. Because this was something that he knew that the dark side [Department of Defense] folks were capable of doing this, and he wanted to pull NASA into that area. I think he learned how to sell projects and underbid them in a place where nobody really cared about what it eventually cost if it eventually worked. NASA is much more in the open with those sorts of things. That cost growth is not something that is unusual in the defense world. It was harder for everybody to swallow in the NASA world.
ZIERLER: You mentioned right at the beginning of our talk it's really the past ten years when you've been so closely focused on exoplanets.
ZIERLER: What was it that pulled you in so much? Was it the James Webb?
BEICHMAN: It was also the ground-based stuff. Also, I'm director of an exoplanet institute. So, it's the transit work. It's the radial velocity work. It's the fact that all these things are hopping. One of the things I try to do here at the NASA Exoplanet Science Institute is make sure we have our arms around all these different parts of exoplanet science.
ZIERLER: When did the Institute actually launch?
BEICHMAN: Like I say, it started out as the science center for the SIM mission. At that point, it was the Interferometry Science Center, ISC. Then I came down and eventually it became the Michelson Science Center, the MSC.
ZIERLER: Who is Michelson?
BEICHMAN: Nobel laureate, one of the—
ZIERLER: Oh, that—okay.
BEICHMAN: That Michelson.
ZIERLER: That Michelson.
BEICHMAN: Early interferometerist.
ZIERLER: Yes, yes.
BEICHMAN: Because that seemed a good name to honor somebody.
ZIERLER: I assumed it was a rich guy, but sometimes it isn't. [laughs]
BEICHMAN: No, it was just a science guy. That was the Michelson Center. Then when SIM went away completely and was no longer doing interferometry, we decided we had to rename it. When I came back from JPL and Anneila had gone away, SIM was gone, so we were looking for a name, and NASA Exoplanet Science Institute became the name I chose, to represent what we were going to be doing, which was working on all aspects of exoplanet science, making the data available from transits, radial velocities. We would develop this whole big archive for all the different datasets. We were operating the Keck interferometer. There were a whole variety of things that we were doing, so no one technique was going to dominate.
ZIERLER: What is the value, having an institute as a clearinghouse of exoplanet research, as opposed to lots of different scientists and astronomers working globally on their own? What is the effect of that centralizing component?
BEICHMAN: I think what makes it important is that no one technique tells you about a planet. It's the adage of the elephant. If you've got radial velocity, you've got the leg. If you have a transit, you have the trunk. If you have an image, if you have a spectrum from a transit, you have something else. But until you have the mass of the planet, the radius of the planet, the atmosphere of the planet, all those disparate different pieces of what make a planet, you can't really understand what it is, what the character is. Is it a gas giant? What kind of a gas giant? Is it a rocky planet? Is it a planet that eventually has life? You want to gather in all those disparate techniques, put them in one place, let them coalesce in one place where then you can draw out and say, "Okay, I need to find a planet that fits these criteria." If you only had the transit data, or you only had the radial velocity data, you couldn't do it.
ZIERLER: That really makes me think that the 5,000 and counting exoplanets, every single one of them has been hard-won. You have to fight to make sure each one of these criterion is met in order for it to join the club.
BEICHMAN: To make it. So when Kepler finds something, a significant fraction of things that make a dip aren't necessarily planets. There's lots of false positives. It could be an eclipsing binary star, so you have to show that, okay, the dip is not so big that it could be from an eclipsing binary. You have to show that it's not just some noise in the star itself. There are just lots of different steps along the way to validate these things. Then they get into the astronomical literature, so we pull them in as a confirmed planet, but you still need to know the mass and the orbit. If it's just radial velocity, how do you start to look at its atmosphere? Webb is now going to look at the atmospheres of these planets. You'll start to say, "Does it have carbon dioxide, CO, water?" All these different things.
ZIERLER: Now, all of this corroboration suggests that we simply don't have the observational capacity just to look and see that it's a planet.
BEICHMAN: Oh, it's a real challenge.
ZIERLER: Does Webb change that equation?
BEICHMAN: No, Webb is very much—it's the last telescope in the chain when you say, "I now have a well-validated, well-characterized planet that I know in detail, and I now want to ask the question, ‘What is the detailed composition of this planet?'" You don't want it playing the role of validation or initial characterization. You want it to come in to be the surgeon that is going to give you the final diagnosis. Having gone through the general practitioners, and you've already got the MRI scan and everything, now this person is going to come in and give you the final diagnosis. Because that's the kind of data that Webb can provide that nothing before it has been able to provide. This idea of using the transit technique has been challenging before. Spitzer could do a little bit of it, but most of the transiting planets came after Spitzer had used up all of its liquid helium, so it only had two of its photometric channels left, no spectroscopy. Hubble was restricted to a very short set of wavelengths, and a lot of the interesting molecules are all at longer infrared wavelengths. Webb has both the aperture to collect lots of photons and a whole suite of instruments that will really let you look in real detail to say, "This planet has CO2. It has methane. It has this. It has that," and put it all together. You want to make sure that Webb time, which is really precious, only goes towards the best planets, and that's what all the preceding steps put together—the RV, the transits, whatever other stuff you can come up with allows you to say, "This is the planet I want to spend 50 hours of Webb time on."
ZIERLER: Did you ever get hopeless that Webb would never come to fruition, or you always kept the faith?
BEICHMAN: Kept the faith. There were just enough people pushing on it. At some point, the sunk costs become such that it's hard-pressed to imagine them canceling it. But, it's always possible.
ZIERLER: What was launch day like for you?
BEICHMAN: Super exciting. I had been exposed to COVID, so I didn't get to go to Arizona to be with our instrument team to watch it happen. I was up with my daughter in Seattle, and we watched it. It was fabulous. When you actually saw the launch work, and then that first thing where you could see on the camera on the launch vehicle, you could actually see the solar panel deploy, and know that things were working, that was a big step. Everyone thinks the launch is the riskiest part; it's actually the safest part. The space business is really good at launching things. There are a lot of other things that could have gone wrong, so that just began the six months of terror.
ZIERLER: Are we in the safe zone now? Has it been long enough?
BEICHMAN: Oh yeah, it's fabulous. There's little bumps and hiccups, but nothing serious. Everything just has worked better than we imagined.
ZIERLER: The technology, it's frozen; it is what it is out in space at this point. What more can the James Webb Telescope do that it hasn't done yet?
BEICHMAN: Oh, it's just beginning. It is doing the stuff we thought of before we saw the sky at these levels of sensitivity and at these wavelengths. We've done the stuff we could imagine; we're now exploring what the sky really looks like, and starting to do the stuff that we couldn't imagine before we launched it. There will be lots of stuff we can do that we planned to do, but as we start to explore how well Webb works, what secrets get revealed with high redshift galaxies and so on, that will be the fun for the next—not just five years. One thing that the Arianespace people did so well, because we launch things really well these days, is put us exactly into the right orbit. So instead of having to use any fuel to get to the right orbit, all that fuel is still on board, and Webb will go for 20-plus years.
ZIERLER: And Hubble places that expectation that it should go for that long?
BEICHMAN: Yes. Of course, Hubble had help.
ZIERLER: Right. [laughs]
BEICHMAN: Which Webb will not, but so far, all of this is working.
ZIERLER: Besides the confirmation process that it plays for defining an exoplanet, what have we already learned from Webb?
BEICHMAN: We're just now starting to see the benefit of all the different wavelengths. You can start to see water and methane. You're just starting. Remember, we're only still obtaining the first datasets, so people haven't really done a lot of publishing yet. So when you ask me that question a year from now, I'll have a much better answer.
ZIERLER: We're really just in the thick of it now.
BEICHMAN: People are just now getting their data from the proposals they put together two, three, five years ago. They've been polished up and made better as things got delayed, but we're still just fiddling with the calibration. That's what I was doing before you came in. So, it's still very early days, but I think we'll see a lot of surprises in terms of what these planets are made of, what their composition is, what the effects of weather are on planets. We'll be looking at global circulation models on planets. We'll be looking at how the composition of a planet changes relative to where it is away from its host star. How does its composition change as the composition of the star changes? There's going to be tons of stuff.
ZIERLER: Now that we have worked right up to the present, we're looking into the future. For the last part of our talk, maybe I could ask a few general retrospective questions, and then we'll end seeing what's to come. For you, looking back really at the dawn of infrared astronomy, what has been most exciting for you, just to be a part of all of these developments?
BEICHMAN: Every time we pop the cover off of one of these space telescopes, that first glimpse of the sky is very dramatic. IRAS was the first, and you saw that picture; I was there at the control room—it was in England—when that cover came off, and you see the sky for the first time. That was fabulous. Watching the equivalent happen on Spitzer was terrific. Anytime an instrument we're working with has its first light, those are really very exciting moments. Then, as you start seeing discoveries unfold. Working with the Spitzer data, we started to find all these different planets having more or less levels of this leftover rocky stuff. That was my big project on Spitzer. We've got a project coming up on Webb which is to look for our closest solar-type star neighbor, Alpha Centauri. We're going to use Webb to look and see if it has a planet in its habitable zone. Won't get down to Earths, but I've got four or five targets that are very favorable targets—hopefully to find planets around them. We don't know; we'll find out. Hopefully at least one of them will have a planet. Obviously Alpha Cen would be super exciting if it did, because that's a target that, it's so close you can really study that in great detail with things like—not TMT; it's in the wrong hemisphere—but the southern large telescopes.
BEICHMAN: GMT, or the VLT or the European ELT, will be able to really home in on a planet around Alpha Cen and study it in great detail. So, those will all be exciting things to come, and hopefully one of those will strike gold.
ZIERLER: Because all of this work is fundamental research—it's not really applied—what have you learned about advocating the importance of learning about our universe, even if it doesn't have that immediate societal benefit?
BEICHMAN: I think the biggest thing it does is it helps bring people into science. I'm writing a book review of this book by Don Goldsmith called The End of Astronauts. He and Martin Rees. I'm writing this for Physics Today. I noted, in my case, I was brought into science by sitting in darkened gymnasiums watching Mercury and Gemini lift off and splash down. I think kids today aren't brought into science because of the manned program, but for the last 20 or 30 years, it has been because of pictures from Mars rovers, from Hubble. It has been the wonders of space science. Maybe with getting people exploring Shackleton crater, that will change again, but the balance has definitely been space science inspiring people to be interested in looking up, taking an interest in the world around them. I think that's probably the biggest societal impact. Then, separately, on an intellectual level, just addressing these 2,000-year-old questions. With real answers; we're not doing it with philosophy. As much as I like philosophy, it did not provide those answers. You cannot ideate yourself into knowing how planets form or life forms; you can go and look, and that's what we're doing. So, we're knocking off terms in the Drake equation.
ZIERLER: Given that you started your career when computers were quite primitive or not even a factor—
BEICHMAN: I remember getting my first HP-35. That was my senior year of college. That was awesome! A calculator, in your pocket!
The Revolution in Computation
ZIERLER: Given what computers are capable of doing now, how has that changed astronomy and what can be accomplished as a result?
BEICHMAN: Oh, it's clear that you can't have surveys like the WISE survey or something like that, or Kepler or things like that, that are capable of processing huge amounts of data, and then sorting through it and finding the interesting bits. That clearly is something that couldn't be done before computers operated at this level. You couldn't design things like Webb without finite element analysis capabilities at this level. Those are all things that take computational resources to make the equipment that we want to use and then to analyze the data we get, particularly for some of these very complicated giant surveys. Certainly, simple individual instrument, looking for the radial velocity wobble or something, you use the computational power, but it's not that critical. I could do it on my laptop. It's nice to have a powerful laptop. But there's some stuff we're doing that takes huge computer power. That's where things like these big surveys come in. That really does take advantage of the big computer revolution, maybe even some AI or machine learning to just track the interesting bits. Because it's not that you found a billion sources; it's how do you identify the ten interesting ones. The more sources you have, the more you need to be able to weed through the chaff and find the interesting ten sources you're going to write papers about for the next 20 years.
ZIERLER: Looking to the future for you, will Webb keep you busy for as long as you want to remain active, or are there other observational projects that you might jump in on?
BEICHMAN: I'm working on this Keck instrument with Dimitri, HISPEC. We're also putting a laser frequency comb on another instrument at Keck that exists, on NIRSPEC. So we've been working on that sort of infrared radial velocity work. We've been working with some of the people on campus—Kerry Vahala—to develop what is basically telecom technology and applying that to doing radial velocity work. That's the instrument we have at Palomar. It is one we've developed at Keck. So, that will keep going for a while. So, there is certainly stuff in ground and space to keep me going. I don't have any real projects on the Roman Telescope, although they have a coronagraph on board that I'm pushing to make sure that we get the most science out of it. We put together JPL's first coronagraph. Our contribution to the NIRCam instrument was a coronagraph that we built up at JPL, and I'm using that—separate from the transit technique, we're also using Webb to do imaging to look for these young planets. That's not as fruitful as looking at the transit spectroscopy, but it's still a nice niche. So that's what a couple of my projects are. Roman takes that coronagraphy to the next level by a factor of 100 or so, and so I might dabble in that, when it gets going. But more, I'm interested to make sure that some of the people here have the opportunity to work in it, so I'm working on mentoring a couple of people to make sure they get science with Roman when that comes along.
ZIERLER: This is generational planning you're doing.
ZIERLER: Finally, last question, looking way into the future. To go back to Dan Goldin's dream of taking that picture of an Earthlike planet, clearly the technology is not there yet, to achieve that level of resolution where you don't need all of these other corroborating factors; you could just look plainly. How do we get there? What will it take before we have that observational capacity to just go out to an exoplanet and achieve that level of resolution and potentially see oceans and forests and clouds and who knows what else?
BEICHMAN: We looked at that, because Dan said, "Look at it." It doesn't violate much in the laws of physics; it violates an awful lot of the laws of engineering. You need basically a Keck telescope per pixel that you want, separated by a few hundred kilometers. So, how you actually make all that work, not to mention afford it, that's way out there. I don't see that happening anytime soon.
ZIERLER: This would be like Webb times what? What would that look like?
BEICHMAN: A thousand. It's off-the-charts hard. You can write down the planet's equations, and say the resolution you need is so-and-so, so that means you need a baseline of so-and-so. If you want to have a thousand-kilometer resolution, which is, say, a ten-by-ten pixel image, in the visible, at 10 parsecs, that means you need a baseline of 1,000 kilometers, or whatever that turns out to be. To collect enough light in each of those pixels on the planet, which is not the total light from the planet but just one one-hundredth of the light of the planet, you need a lot of collecting area. So, you put that together, and how do you then bring the light beams together to make an interferometer to even do that? It's a mess. So, it was never, I think, a real vision. I think the way to do that is you hook onto the webcam that another civilization has put onto their own planet, hook up to their ISP, and download the image from that.
BEICHMAN: That's the easier way to do that.
ZIERLER: Well, one thing to look forward to!
BEICHMAN: Yes, one could hope!
ZIERLER: This has been a great conversation. I'm so glad we were able to do this. Thank you for having me.
BEICHMAN: You bet.