NASA Science Mission Directorate
Oral History Project
Edited Oral History Transcript
David D. Morrison
Interviewed by Sandra Johnson
Moffett Field, California – 9 May 2017
is May 9th, 2017. This interview with Dr. David Morrison is being
conducted for the NASA Headquarters Science Mission Directorate Oral
History Project at Ames Research Center in California. Interviewer
is Sandra Johnson, assisted by Jennifer Ross-Nazzal.
Thank you for allowing us to come to your office and talk to you today.
I want to start by talking about your background and how you first
became interested in becoming an astronomer and what led you to your
work with NASA.
I was interested in space and astronomy clear back into grade-school
level, as I know a lot of young people are. I never outgrew that.
So I ended up going to the University of Illinois [at Urbana–Champaign]
and taking a physics degree, but with a real interest in astronomy
and spending time at the observatory there.
I then went to Harvard [University, Cambridge, Massachusetts] for
graduate school, in astronomy, and was fortunate to have Carl Sagan
as my adviser. He was an inspiration in all sorts of things, including
especially interest in planetary science.
When I went to Harvard I had no particular focus on planets. I assumed
I would study galaxies or stars, but Carl Sagan really hooked me on
planetary science. I particularly remember the title of the public
lectures he gave, “Planets Are Places,” which reflects
the idea that he’s written about many times, that we start out
thinking of the planets just as points of light in the sky, while
as exploration happens they become real places. We can ask ourselves
what it would be like to stand on the surface of a planet.
That inspired me, and obviously that directed me toward NASA because
NASA was in the process then of supporting ground-based telescopes
as well as space missions. I remember watching from Harvard when the
first Mariner [interplanetary probe] flights went to Venus and to
When I completed my degree at Harvard, I was hired by the University
of Hawaii [at Manoa] Institute for Astronomy, a place with strong
NASA ties. At that point NASA was just completing the construction
of an 88-inch telescope at Mauna Kea Observatory [Big Island of Hawaii].
And not too long after I arrived in Hawaii they began work on the
IRTF, the NASA Infrared Telescope Facility, also on Mauna Kea. Ultimately
I ended up being director there for four years.
I spent 17 years in Hawaii as a research astronomer with some teaching,
but primarily a research appointment, and I focused on planets and
infrared. One of the things that made Mauna Kea such a remarkable
site for an observatory was its unique capability for infrared observations.
The Earth’s atmosphere, and in particular the water vapor in
the Earth’s atmosphere, is the greatest problem for infrared
because it absorbs and emits. To get above a third of the atmosphere,
which you are on the summit of Mauna Kea—where it’s dry
and cold air coming straight across the Pacific, not much water vapor
in it—in effect opens up the infrared window.
We were pioneering in making infrared observations from the summit
of Mauna Kea, and most of our work was directly relevant to NASA programs.
We were almost entirely funded by NASA. Thus I had connections with
NASA all the time I was at the University of Hawaii, even before I
considered actually working for NASA.
thought it was interesting that you said when you got to Harvard and
then Carl Sagan was your adviser. Did his reputation precede him at
that point? What was that experience like, having him there as someone
to inspire you?
Carl Sagan’s reputation didn’t really precede him for
me. Remember, he was just a young guy then. He only had his PhD two
years from the University of Chicago. He’d been out in California
the past two years, beginning his integration of understanding life
science—what we now call astrobiology—with astronomy.
He arrived as an Assistant Professor at Harvard just after my first
Sagan introduced a graduate-level planets course. A few of us took
it, and some of the graduate students scoffed at it or went and listened
to a lecture or two and said, “No, this guy isn’t serious.”
But I thought he was an inspiration, and so did a few other people,
including Jim [James B.] Pollack and Jim [James L.] Regas and Joe
[Joseph F.] Veverka, who all became Sagan’s students as they
progressed through their graduate career.
stayed with him even after he left for Cornell [University, Ithaca,
I went with Carl for two years to Cornell University, the problem
having been that Sagan was denied tenure at Harvard. Very common.
The great majority of people who come in as assistant professors,
at least in the sciences, don’t stay. But it was traumatic for
me, because I was in the middle of my thesis with him, and suddenly
it was announced that he was leaving.
There was some effort among the Harvard astronomy faculty to get me
to drop him as thesis adviser and change my topic, even though I was
halfway through my thesis. I resisted that and Carl resisted it on
my behalf. Ultimately it was agreed that even though he was leaving
Harvard and going to become a faculty member at Cornell, I could continue
my Harvard degree and finish with him, and that’s exactly what
mentioned that when you went to Hawaii the funding was coming from
NASA. But you also at some point, I believe it was 1981, became an
Acting Deputy Associate Administrator for Space Science on an IPA
[Intergovernmental Personnel Act] appointment. Was that the first
time you actually went to a NASA facility and worked? Or did you do
something else before that?
I actually took two IPA appointments to [NASA] Headquarters [Washington,
DC]. One was for two years in about 1975, within the Planetary Science
Division. Not a senior position, primarily as a staff scientist, someone
who’d interact with the regular NASA people. It was a lot of
fun. It gave me a valuable perspective on what NASA was about and
probably set me up for the later position.
I was a participant in the Voyager [robotic] missions in the late
1970s; I was in California at JPL [Jet Propulsion Laboratory, Pasadena,
California] for the Jupiter encounter, and then for the Saturn encounter,
which were just extraordinary experiences. We were getting the information
live in real time from the spacecraft. At Jupiter a new image arrived
every two minutes. Every one of those images showed things that nobody
had seen before. You just couldn’t tear yourself away from sitting
in front of that screen and seeing new images come in one after another.
I was having a great time, and the same thing was true with Saturn,
although the images came in less frequently because of the larger
Andy [Andrew J.] Stofan was the new Acting [Associate Administrator]
for what’s now the NASA Science [Mission] Directorate. Andy
Stofan had been Deputy, and Tim [Thomas A.] Mutch had been the Associate
Administrator of Science, using today’s terminology. Tim Mutch
was killed in a climbing accident in the Himalayas on vacation, and
his body was not recovered. Under those circumstances, NASA wasn’t
permitted to advertise for a new Associate Administrator for a while.
Andy Stofan, who was a wonderful guy, a longtime engineer operating
with NASA going back to Glenn Research Center [Cleveland, Ohio] as
well as Headquarters, was not a scientist. He wanted a scientist to
come be his deputy temporarily until they could straighten out this
Stofan invited me to come for less than a year to NASA Headquarters
as the acting Deputy Associate Administrator, which was a high-level
position, which I really didn’t have much management background
for, but I was an enthusiastic space scientist. That worked out just
fine for me, and I think it worked out fine for everybody. At the
end of that period I went back to the University of Hawaii and NASA
appointed a new real Associate Administrator for the Science Directorate.
talk about Voyager for a little bit and any other involvement. I know
you said that you got to be there at JPL when the pictures were coming
in, but did you have any other involvement in the program itself as
far as the work or anything that was being done with any of the research?
I didn’t have any administrative responsibilities with respect
to Voyager. I also was there for the Viking missions [to Mars] with
even less official sanction. But as an active planetary scientist
I was invited to come and spend some time at JPL. I will never forget
the excitement of planning for that first landing on Mars in Viking.
The Mission Director, Jim [James S.] Martin, was responsible to safely
land for the first time on the surface of Mars. He held meetings every
day with the whole science team, as we were beginning to get the data
as we were approaching Mars and then going into orbit. I sat in on
them, although I was not quite a member of the science team. He appointed
three wise planetary scientists to provide him advice on where to
land: Carl Sagan and [Harold] Mazursky and Toby [Tobias C.] Owen.
Every day they studied whatever data had come in, and there was a
general meeting discussing what new information there was on finding
a safe landing site.
The problem for Viking finding a safe landing spot was that we didn’t
have high-resolution surface images like we do today. An object a
meter or two or three meters across, like this desk, could not be
seen from orbit. Yet if the spacecraft landed on it or landed with
one foot on it, it would be wrecked. The challenge was to infer what
the smaller scale roughness and topography was from the images and
other data from the spacecraft which did not have the resolution to
see these details on the surface.
It was really a tricky question. The landing on Mars was delayed a
couple of weeks while this process went on, and it was really exciting.
Afterwards I got to know Jim Martin better and he told me the interesting
thing—he said he had spent his last 15 years working on this
project at Martin Marietta [Corporation]. Everything he had professionally
was invested in this mission. He said, “If this landing was
successful, I knew I would become a vice president of the company
and make a lot of money. If it were unsuccessful I knew I would lose
my job.” That was just another perspective on how important
it was to make this first landing on Mars a success.
In the case of Voyager (which was a flyby, not a landing mission),
there wasn’t any dramatic decision making of that sort, but
there certainly were lots of interactions with the spacecraft to set
up the observing sequences and look at the right things at the right
time. It quickly became apparent that the moons of Jupiter and the
moons of Saturn were equally if not more important than the planets
themselves, with this tremendous variety of geology, for instance,
on the four Galilean satellites of Jupiter.
The process was so interesting because it condensed the whole normal
scientific activity into such a short time. Literally, we would get
the images from one day, we would discuss them among ourselves on
the imaging science team, and there would be a news conference the
next morning at which some of the best images would be shown, and
if possible some interpretive things would be said about them.
Just one example. Was Io [moon of Jupiter] going to be heavily cratered
or not? Then that same day more higher resolution images would come
in and might change the conclusion. The next day you would have another
press conference and say, “Ah, we thought there were going to
be craters, and now we see there aren’t. Now we have a whole
new idea of how the geology of Io is working.”
This took place over a period of a week or so as the spacecraft approached
Io. In ordinary science there might be a year interval between the
updates, but with Voyager they were updating every day or two. It
was really a fascinating experience, and it brought the scientific
can talk more about it later, because I know you’ve dealt a
lot with educating the public about astronomy and astrobiology. But
Voyager, you’re saying those news conferences were happening
so soon, and the pictures that the general public was seeing. Talk
a minute about the reaction of the public and what you were seeing
as compared to earlier in your work. Did it change as far as the interest
and people wanting to see more, and being more excited about NASA
at that point?
One of the great things about most NASA missions, and it certainly
was true of Voyager, is that they took lots of pictures. The first
Mariners didn’t even carry cameras. That was because there were
a couple of old-time astronomers who said, “You can’t
tell anything from a picture. We want quantitative information, we
want to test a hypothesis. So we will suggest a hypothesis and design
an instrument to make precisely that measurement.”
Sometimes that worked and sometimes it didn’t. In the case of
the first Venus mission [Mariner 2] the primary question was whether
the surface was hot, whether the radio emission that we were detecting
was coming from a hot surface. So they designed a very simple experiment
to look straight at Venus, look to the side, look back again. I don’t
mean look with a picture, but measuring the thermal emission, and
that would tell them the answer to whether the radiation was coming
from the surface or the atmosphere. It happened that the answer was
found by astronomers on Earth while the spacecraft was en route to
Venus. Without a camera, we didn’t have much opportunity for
Once our spacecraft started taking pictures and spectra with broadband
instruments, there was this tremendous opportunity for discovering
things that were never thought of. That was exciting for the public
as well. It had been true in the Apollo missions, and now for the
first time we were seeing pictures of Mars and of Jupiter and Saturn
and their moons. It was an easy sell for the public. It made the solar
system come alive.
It went back to Carl Sagan’s “Planets Are Places.”
They were no longer just points of light. They were geological entities
with all kinds of processes going on. Sagan was one of the best exponents
of sharing these discoveries with the public. That was when he was
going on Johnny Carson [The Tonight Show] with his examples. He would
come in with the latest Voyager pictures, two or three of them, and
show them to Johnny. Johnny would hold them up to the camera. That
was a way of reaching a lot of the public.
The press conferences also were really dramatic sometimes and we had
as many as 60 or 70 members of the press at JPL. It was a great big
science party. Often the press focused on some individual scientists,
not just Carl Sagan but others, and they interviewed them and they
put them on TV. I think it was probably second only to Apollo in the
kind of excitement generated in the public about NASA programs.
was interesting too, Carl Sagan being a scientist. Like you said,
at that time he was appearing on Johnny Carson. He was on different
shows, he was being interviewed. He was becoming popular, almost a
rock star not to overuse that term. I don’t think we had seen
that in science before.
We certainly hadn’t seen it in the planetary science arena.
It was while the Voyager Saturn mission [flyby] was happening that
Carl finished Cosmos [A Personal Voyage], his  TV show that
he’d been working on for more than a year. Suddenly that was
added to the mix, because now Cosmos was shown weekly.
I went out with Carl to dinner near JPL shortly after the show started
being shown. We were in a little quiet dark Thai restaurant in La
Cañada [Flintridge], sitting in the back, talking to each other,
and a guy came over from another table and said, “You’re
Carl Sagan, aren’t you?” and how wonderful Cosmos was.
Carl turned to me after he left and said, “This is happening
to me suddenly all the time.” Once you have been in people’s
living room on their TV, they feel they know you. They can come up
and talk to you. It was a mixed blessing. Sure enough, within a year
or so Carl was traveling with a nanny for his children, with people
to chauffeur him around, and he had received so many death threats
at Cornell University that they really went overboard to protect him.
His name was taken off all the university directories, was removed
from the directory of his office building, it was removed from his
door. The only way into his office was through his secretary’s
office. And Cornell posted a full-time policeman at his house in Ithaca
day and night for about a year. So that is the downside of suddenly
guess what he was talking about, I assume people found it threatening.
Apparently. Or they’re just kooks. If somebody becomes famous
they attract this sort of thing. It changed Sagan’s life very
much, and for the better or the worse I don’t know. But he wasn’t
nearly as accessible to the public, to students, and to friends after
that, because of these safety concerns.
became the Chief of the Space Science Division at Ames in ’88.
What made you decide to leave the university and work for NASA full-time?
My career at the University of Hawaii had partly drifted into science
management. I was the Director of the NASA infrared telescope, the
IRTF, for four years. I spent two years as the Acting Vice Chancellor
for Research at the University of Hawaii at Manoa. This interested
me. I was also constantly involved with NASA missions, NASA committees,
flying back and forth. It’s a long way to fly from Hawaii to
Washington. It’s pretty long flight to get to JPL, but to Washington
it’s no fun. You essentially have to spend one night on a plane
to get there.
All these things joined in to make me feel that if I was going to
spend all this time with NASA and NASA missions, maybe I should actually
work for them. I knew Larry [Lawrence] Colin, who was the longtime
head of the Space Science Division at Ames. I knew him, I liked him,
I’d been to Ames a number of times. When I found out Larry was
going to retire I decided I would apply. I got in touch with him,
he introduced me to the leaders of NASA Ames, and after a couple of
interviews I got the position with a minimum of paperwork.
talk about Galileo [Jupiter mission]. It launched [in 1989] right
after you became the Chief of the Ames Space Science Division. Were
you working early on in Galileo? You said you were on committees,
you were doing things for NASA. Had you been working on that project
I had been involved in the planning of the Galileo project. Following
on the success of Voyager at Jupiter, that was obviously the next
thing to do. It was a terrific mission, but it had its problems. First
of all there was a delay of several years because of a [1986 Space]
Shuttle [Challenger, STS-51L] accident.
There were problems with the funding. We had gone through an issue
with the [President Ronald W.] Reagan administration when they tried
to cut the planetary program; at one point they had actually proposed
turning off Voyager after the Saturn encounter and not even collecting
data at Uranus and Neptune.
It was a very long struggle, but I did become involved as the Galileo
Program Scientist at NASA Headquarters for a year or so at a very
important time, because that was when we were trying to finalize the
plan for the instrumentation. I was privileged because of my role
at Headquarters to actually give the presentation to the senior management
of what the proposed payload would be.
Selecting a payload for a planetary mission is a delicate balancing
act because you have many more good ideas and good instruments proposed
than you have either the money or the mass capability to carry. Trying
to put together a balanced payload is not just picking the best instruments,
but trying to make sure you have a balance of imagers and spectrometers
and UV, ultraviolet and radio and all of this.
I was involved at that point in the original selections. Then afterwards
back in Hawaii I was able to get a position as Galileo Interdisciplinary
Scientist as sort of a reward for having done this work in setting
up the mission itself.
you mentioned, there were a lot of delays. A lot of it was even political
influence because of different constituents and congressmen wanting
their areas to have those contracts, and of course the Challenger
accident. But it finally did launch after you were at NASA full-time.
Ames was responsible for the Jupiter atmosphere probe. If you would
talk about what the expectations were as far as that probe mission,
and then of course the Galileo mission itself and the timeline and
what happened with it.
Galileo was designed to be a comprehensive years-long study of the
Jupiter system. You had three groups of science instruments and approaches.
One was the study of Jupiter itself. Another was a study of its magnetosphere
and magnetic field, all of the issues of the space around Jupiter.
The third was the satellites [moons].
I was primarily interested in the satellites. We really wanted to
follow up on the discovery of erupting volcanoes on Io, which at that
time was unique. We knew of no other place beyond Earth with active
volcanoes. We also wanted to determine what the heck was going on
with Europa, which was smooth, with no craters visible in the Voyager
Galileo was very ambitious. Part of the way you achieve that is you
put on modern instruments which have high capability and high data
rates. You put in a radio transmission system with high data rates
so you can get back images every few seconds, or whatever the data
may be that you’re trying to collect.
Then when Galileo was launched and we discovered we couldn’t
open the high-gain antenna, most of that was lost. We had all the
same instruments, all the ability to point, all the tour through the
system, but we could transmit less than one percent of the data that
were collected back on Earth. That was a terrible blow, just gutted
But yet we knew we still had these supercameras and superspectrometers.
So we faced a very complex question of sequencing, of deciding exactly
what was the most important data to collect and return to Earth. If
you had a place like Europa and knew you could only get high resolution
images of one or two percent of the surface, how are you going to
decide which one or two percent to do? It was exciting but very difficult
and tiring. You knew you had this one opportunity to use these terrific
instruments but you were so limited in the data you could get back
to Earth. .
The Galileo atmospheric probe, which I had not worked on, became interesting
to me after I came to Ames, since it was designed at Ames. It was
coasting on its own through this whole mission. It had been sitting
on its own before and during the long delays before the mission was
launched. No one knew if it could survive this long hibernation.
There was a big project here at Ames on the batteries, how to select
long-lived batteries. There was a special room that was filled with
batteries of various ages and they’d take them out and monitor
how they were doing on the ground, because you couldn’t monitor
them on the probe.
Finally we reached Jupiter [December 1995]. It was an unforgettable
day with everybody gathered at Ames for the event. I knew the people
who’d been involved in building the probe. They put much of
their career in this, they’d waited for many years.
The probe is a one-shot thing. It was designed to broadcast all of
its information while it was descending through the atmosphere, but
most of that data was collected on the orbiting spacecraft and sent
back slowly. The initial direct-to-Earth transmission was just going
to be a simple yes-no signal. Did it work? Was it in the Jupiter atmosphere?
Was it taking data or not?
We all gathered in the Ames cafeteria, everybody standing around extremely
nervous just waiting for that beep or no beep. I was a little shocked
when the person who had been the project manager said, “I think
there’s a less than 50 percent chance it will work” after
all the delays and all this inability to monitor how it was doing
along the way.
Then that beep came back and boy, the crowd erupted in celebrations.
The probe turned out to be extremely successful. The only problem
with the probe—and it really isn’t a problem, but it didn’t
comply with our expectations—was that it went into a very, very
dry part of Jupiter’s atmosphere, into a hole sort of, where
there was very little water vapor, and it didn’t encounter the
water clouds that it should. But it went deep into the atmosphere
and gave us a lot of information about atmospheric composition and
cloud structure. It made us think, “Boy, we wish we’d
had more than one probe so we could compare with other places.”
the information that was coming back from Galileo, because of the
antenna problem, actually lost? Or was it just slower getting what
The cameras for instance were capable of taking high data rates and
recording them on a tape recorder. But there’s no point in doing
that, because you couldn’t play it back. So yes, in principle
Galileo could collect the data, but if you can’t retrieve it
on Earth it might as well not be there.
that time, you were in charge of the Ames Space Science Division.
That included astrophysics, planetary science, and exobiology. I want
to talk a little bit about exobiology and NASA’s role in that.
You hear that term in the early ’60s, then astrobiology became
something in the early ’90s. What were the differences between
exobiology and astrobiology, and why was the term astrobiology substituted
Being the Chief of the Space Science Division at Ames was a really
great position because we had many of the best scientists in NASA.
Many of them were Carl Sagan’s students. There seemed to be
a link between Sagan and his students and they would come here for
a postdoc [postdoctoral fellowship].
I got to know Hans [M.] Mark, who had been the Director of Ames earlier
and by this time was in Washington, in the Department of Defense [Director
of Defense Research and Engineering, and later Secretary of the Air
Force]. He told me once, during a visit to Ames, “Dave, you
have the best job in NASA for a scientist. There is no better place
than the Space Science Division at Ames. Being the Chief of the Space
Science Division at Ames is really the top.”
Of course that made me very happy, and I told that story to my successors
in that job, including the current Chief [Steve B. Howell] who just
came on board a couple months ago. I went to him and I said, “Hans
Mark said you have the best job in NASA for a scientist.”
I was less familiar with the life science part. I had learned a little
bit from Carl Sagan, but I had been primarily involved in ground-based
telescopic observations, in spacecraft observations.
The issue of exobiology and later astrobiology is complex because
you’re asking questions about things that are not even known
to exist. Ultimately the objective is to discover extraterrestrial
life, but we have no evidence whatsoever even today of extraterrestrial
When exobiology was formed, the goal was to study the biology on objects
beyond Earth, and in particular Mars. A lot of exobiologists were
involved in the Viking landers on Mars. One of the most elaborate
instruments in the life detection system was built here at NASA Ames.
But they didn’t find life on Mars. We were actually on the surface
with Viking so they could take some of the soil, collect it, put it
into miniature wet labs basically, and do tests on it to see if there
was any sign of metabolism. There wasn’t.
It was not a for sure negative. We only looked at the two places on
Mars where the Viking spacecraft had landed, and you could only take
a scoop of soil within a meter or two of the spacecraft. You could
only dig a few centimeters deep. You could hardly characterize the
whole planet from that. But the conclusion that NASA came to, and
the science community, was that Mars didn’t have life on the
surface. It didn’t have the kind of life we hoped.
Carl Sagan was on the imaging team on Viking. He even went so far
as to say, “Look, we must try to get any possible information.”
He said, “I want to look at every image taken of the surface
from the lander spacecraft to see if something might walk past.”
He did this, and nothing walked past. In addition to searching for
microbes, why not? But that’s typical Carl Sagan.
Ames had been involved in a number of things in exobiology, going
clear back to Apollo. Ames had been one of the places that got the
early Apollo samples and analyzed them for evidence of organic compounds,
searching for life or precursors of life or dead life or whatever
it might be, fossil life. With the Mars missions coming up, Ames was
naturally involved in Viking.
But there was this long pause of 20 years after Viking, before we
went back to Mars. There really weren’t any other obvious candidates
for life until Galileo got data on Europa. Exobiology wasn’t
as vibrant a field as we had hoped it would be. There were people
back before Viking who thought there really would be life on Mars,
and we would have a chance to study it. It wasn’t working out
The perspective changed with the shift to astrobiology. First of all,
we were no longer just looking for life beyond the Earth. We wanted
to understand the history of life on Earth. We wanted to understand
more about the origin of life so we could make inferences from Earth
history as to what might have happened other places.
I was part of that discussion. We thought we had an opportunity, and
we also wanted to reinvigorate the parts of NASA that could conceivably
help us determine something about life and habitability outside the
Earth. So we changed the name.
It would have been possible just to morph exobiology, but I think
it’s a truism in NASA, perhaps in the government in general,
maybe in society in general—if you want to do something new,
give it a new name, a new branding, and you get new money. If you
just want to make an incremental change in an already existing program,
you’re unlikely to get any money. So that was part of the reason
for going with astrobiology, but also we really wanted to give astrobiology
a much broader footing in science.
The opportunity came because of the widely publicized discovery that
there was some evidence for fossil organisms in a Mars meteorite [Allan
Hills 84001], the famous Mars rock. It was a controversial finding
from the beginning. But there was no question that the image showed
things that looked like tiny microorganisms, like you would get from
So what to do? NASA agonized for months over how to publicize this.
The people at JSC [Johnson Space Center, Houston] who’d done
the work were very anxious to release the information. NASA Headquarters
and NASA Public Affairs were worried about what would happen and what
kind of reaction there would be.
The JSC scientists did publish a paper in Science [academic journal]
after going through the rigorous peer review one normally has. When
NASA organized the press conference they insisted on having, in addition
to the proponents who had done the work, an outsider scientist who
was not part of it, who explicitly at the press conference criticized
it as, “Look, we’re not sure. There are uncertainties
here, here, here, and here.”
I thought it was a very responsible job that NASA did. It wasn’t
a gung ho sort of publicity, but it still took off. The President
[William J. “Bill” Clinton] had a discussion from the
White House on how exciting this was. The Vice President [Albert A.
“Al” Gore, Jr.] put together a committee of about 20 people
that met for a day with him, including theologians, philosophers,
as well as scientists, to try to explore the importance of this discovery.
That was part of what set us up for astrobiology, but there were other
things. We for the first time had evidence that Europa had an ocean
with perhaps more water in its ocean than we have in ours. There were
thoughts about Titan and its possibility of supporting life on a satellite
of Saturn. We were seeing the beginning of the genetics revolution
and the ability to study life in much more detail at the genetic level.
It just became a very exciting thing.
Dan [Daniel S.] Goldin was the head of NASA then, the NASA Administrator.
He really got interested. For a while he was going around telling
all the NASA managers they should go take a biology course or read
a biology textbook. He was distributing biology college texts and
saying, “We’ve got to all learn about biology.”
I don’t know how many people actually did it, but that was the
in thing at NASA for a little while. The White House had been very
supportive. On that basis, and with Dan Goldin’s enthusiastic
support, we decided to do introduce the new term, astrobiology.
Then the question of the content of this new discipline. I pulled
together a fascinating workshop on the science of astrobiology with
about 100 people here at Ames who met for two or three days. We managed
to get five Nobel [Prize] laureates to come too—some were already
at Stanford [University, California] and [University of California]
Berkeley, so they didn’t have to come very far, but some came
a long way—to try to see how we could formulate this science
of astrobiology and a program that was affordable that could get somewhere.
We ended up with a very broad definition. We said, “We’re
trying to do three things. We’re trying to understand where
does life come from, what’s its distribution, and what’s
its future?” I remember taking that list to Dan Goldin when
we were trying to get his approval, and I think we phrased it very
simply. “Where did we come from, are we alone, and where are
we going?” He said, “That’s far too trivial-sounding.
If this is a real science program you’ve got to phrase it differently.”
So we went back and phrased it in scientific jargon, which I didn’t
think was nearly as good as “where did we come from, are we
alone, and where are we going?”
kind of funny coming from the man that did “faster, better,
Yes, right. We officially adopted the terminology Golden wanted and
unofficially we still used the simpler terminology. But the important
idea was that astrobiology didn’t deal with only extraterrestrial
life. It could be involved with life on Earth. How did life on Earth
start? That’s the where did we come from, what are the general
questions of habitability. Then we can apply that to Mars, to other
places in the solar system, eventually even today we think of it in
terms of exoplanets. So it is a very broadly based field.
A lot of the research that was supported was dealing with microorganisms
on Earth. Some scientists went to the most difficult climates on Earth,
the most Mars-like, like the Atacama Desert [South America], or the
[McMurdo] Dry Valleys of Antarctica.
One of the most exciting discoveries was in the deep [Mponeng gold]
mine in South Africa. You go very deep, it’s very hot, you’re
kilometers below the surface, and some water leaks out. Like any mining
people, they have to pump the water away. But they permitted scientists
to go down two kilometers below the surface, collect that water, and
they found microorganisms in it. Microbes in water that was very deep
in the Earth, probably had no connection with the surface, couldn’t
be supported by photosynthesis.
The ultimate conclusion was that this deep ecosystem actually lived
as a result of chemical changes caused by radioactivity in the rocks.
If that’s true, that gives us a whole different perspective
on life. That says you can have life many miles below the surface
of a planet. It didn’t matter whether the surface was clement
or the Sun shone, whether you had surface water, any of those things,
it could be something deep down.
That doesn’t tell us how it originated, and that’s another
question. Even if life could be supported deep below the surface,
there’s no saying that it could originate there. And it would
be very hard to find on another planet, because we’re not going
to dig mile-deep mines on Mars in order to try to do that. But this
discovery gave us a broader perspective that maybe astrobiology really
mattered, and that we could think of life in ways that were very different
from just the microorganisms on the Earth’s surface.
The original roadmap I wrote for astrobiology also mentioned the societal
parts. We said this is something that is very closely tied to issues
of planetary protection, because if we find life elsewhere, we mustn’t
bring it back to Earth if it could possibly contaminate our planet.
Also there’s forward contamination. If you’re going to
Mars to search for life, the last thing you want is to find it, and
find that the life you found was terrestrial microbes from a previous
mission. There was a big debate about whether the missions that had
already landed on Mars, including several Soviet missions that had
crashed on Mars, might have contaminated the planet already. You have
issues now of how you can transport organic material or life from
one place to another.
We also acknowledged that this was a topic of potentially wide interest
to theologians, to philosophers. What would be the implications if
we found life elsewhere? I always thought that concern was interesting
but perhaps overblown, because a century earlier it was generally
thought that there was life on other planets. [Percival L.] Lowell,
canals on Mars. It was just said, “Well sure, if there’s
a planet Earth, and then there’s Mars and it has water, it’s
going to have life too.”
That conclusion didn’t destroy our civilization, that didn’t
mean an end of religion. It seemed to be taken for granted. But now
after many many decades, nearly a century of saying, “No, there
isn’t life elsewhere or at least we don’t know of any,”
it was thought that it could have a profound effect on society to
discover life on another world.
I don’t think that’s an argument for or against doing
it, but I’m just saying that when I wrote the first Astrobiology
Roadmap we at least thought about some of these broader implications
of astrobiology, and particularly of finding life elsewhere.
of finding life elsewhere, the search for extraterrestrial intelligence,
which NASA was giving funding to as early as 1971, and then there
was a branch within NASA eventually in the late ’80s. Talk about
the SETI [Search for Extraterrestrial Intelligence] program, and the
relationship with NASA and your relationship with that program. You
mentioned earlier about changing names and maybe getting funding,
and I know at some point they changed the name to High Resolution
Microwave Survey, which didn’t help save it evidently.
You’re quite right; that new name doesn’t just trip lightly
off your tongue. I was fortunate because when I arrived at Ames Research
Center and became the Chief of the Space Science Division, the Division
included NASA’s SETI program. SETI experts like Jill [C.] Tarter
and Barney [Bernard M.] Oliver were in my Division.
It was amazing to have Barney Oliver there, because he had been vice
president of Hewlett-Packard [Company] and was one of the most respected
engineers and scientists anywhere around Silicon Valley [California].
Absolutely an intellectual giant, and here he was supposed to be reporting
to me, young guy as head of the Division. I certainly didn’t
ask him to obey all the NASA rules and regulations, which he thought
were ridiculous anyway.
But the point is we did have a SETI program of a dozen or so scientists
and engineers, and we were developing the receiver systems, which
are the critical part of it. You’re searching for very faint
radio signals, you don’t know what they are like. You therefore
need an extremely broadband receiver that’s sensitive to all
different frequencies and cadences that might be coming in. That’s
expensive and it really profited by being in Silicon Valley where
the most advanced electronics of that sort were being designed.
We were a part, in fact the leading part, of the NASA SETI program,
which was scheduled to begin on Columbus Day in 1992, the 500th anniversary
of the [European] discovery of the New World. Two parts—observations
being made at Arecibo [Observatory] in Puerto Rico and at the Deep
Space [Network] facility [Space Flight Operations Facility] near Pasadena
There were two NASA SETI programs, and they were done largely independently.
JPL operated the one that would ultimately be putting receivers on
the Deep Space Net, and we here at Ames had the arrangement, to use
part of the Arecibo time for our part of the survey.
It was cool. I was down at Arecibo on the day when we first turned
on the receivers. I think it was extremely exciting because you realized
that if you could find any evidence of intelligent life, you could
leapfrog over all these other questions. You didn’t need to
know about the life chemistry, life origin, whether there was water
on the planet. If they were out there and they were intelligent and
they had enough technology to transmit a signal that we could receive,
they’re living in a whole different world.
I think you probably know that [science fiction writer] Arthur C.
Clarke’s third law was that any sufficiently advanced technology
will be indistinguishable from magic. That’s kind of what we
thought. We are not necessarily going to interpret what comes in,
and we may never be able to. Two-way communication will not be possible,
but just finding clear evidence of an intelligent technological civilization
elsewhere would be extremely dramatic, perhaps more dramatic than
finding microbes on Mars.
SETI has a lot of public appeal, although in general I think the public
doesn’t understand that you won’t have a two-way conversation.
Almost certainly any signal you receive would be from hundreds of
light years away, and so the delay time—even if you could transmit
back and they could transmit to you—would be many centuries.
But that doesn’t mean you can’t learn from it.
The example that’s often given is we cannot have a two-way communication
with the ancient Greeks, but we’ve learned a lot about them
from reading the things they wrote. You at least might be able, if
you could decipher it, to get a tremendous amount of information,
even though you didn’t have a two-way signal.
That depends of course on whether there’s anything out there
transmitting, and now you ask, “Well, why would they transmit?
Would they just put out a beacon that would reach millions of stars
in the hopes that maybe someone would answer?” Or would you
have to overhear their own internal transmission?
The question then of course is, “Well, what about us?”
We have been transmitting for 70 years at levels that might be detectable
at a nearby star. Our FM [frequency modulation radio], television,
and especially our radar signals, which are the most powerful signals
SETI is a daring thing to do because you have absolutely no way of
estimating the chances of success. But you do SETI because you think
even if the chances are very low, it might be successful, and it could
be so revolutionary that it would be silly not to do it.
Now you worry about analogies. Is that like going into Las Vegas’s
[Nevada] gambling area and putting money into something that has an
extremely low chance of winning? Of course a lot of people do that.
Anybody who buys a lottery ticket is taking that kind of chance because
the chances of winning $1 million on a lottery are extraordinarily
low, but they do it anyway. By analogy, surely we could put 0.1 percent
of the NASA budget into a SETI program and that would be justifiable,
and it could be revolutionary.
We started observations at Arecibo, but just a year-and-a-half after
the program began, in 1993, the Congress terminated it. And didn’t
just terminate it by cutting the money. They forbade NASA to have
anything to do with SETI, told NASA we could not even help private
organizations interested in SETI. For years there were annual questions
and sometimes visits from staffers from the Senate who wanted to make
sure that we hadn’t somehow surreptitiously helped the SETI
Institute or some other organization with federal money.
We were able eventually to surplus some of the electronics and let
the SETI Institute have it. But in general we were watched carefully
to make sure we didn’t do this horrible thing of spending a
little bit of NASA money on SETI.
it was canceled, why do you think they wanted to make sure NASA never
had anything to do with it? What do you think that reaction was caused
I don’t know. At the time I thought about it. I actually don’t
remember the details. It was Senator [Richard H.] Bryan who proposed
this cut on the Senate floor and made comments about little green
men on Mars, and we’ve already sent a spacecraft to Mars and
there aren’t anybody there, and so this is a waste of money.
He clearly had it out for the SETI program. One powerful person in
the Congress can have this kind of influence, so he could send his
staffers out every year to Ames to make sure we weren’t doing
it. Most of my work was not directly impacted, but there were some
people at Ames who lost their jobs. The [non-governmental] SETI Institute
set itself up, and of course has carried on. I later on spent four
years with a half-time IPA appointment heading the Carl Sagan Center
at the SETI Institute, so I like those people a lot.
But even at the SETI Institute very few of the people or funding goes
to the SETI project. The SETI Institute is primarily an astrobiology
organization, and more than 90 percent of their money and their staff
are involved in doing all kinds of astrobiology research that has
nothing to do with SETI. The SETI part just struggles, partly because
there’s no federal funding, and it has to be funded by private
donations. You would think that in a time like this when there are
so many extremely wealthy people, private funding would be available,
but it’s been a constant struggle to even keep a single SETI
program on the air.
back to communicating with the public—Carl Sagan, of course
his  book Contact, I think for a lot of people was their first
exposure to SETI and to radio astronomers and that whole field of
And the book and film were both very impressive, and the fact that
they could shoot it [1997 film] at the [Karl G. Jansky] Very Large
Array [New Mexico], that is so photogenic, and the fact that they
had a highly photogenic scientist doing it. Contact was a powerful
book and a powerful movie.
and I think that conflict in there was probably a reflection of what
was really happening in the world, the conflict between faith and
And the fact that the first response of the federal government to
this discovery is to send guys with guns to say, “Stop, what
are you doing?” Partly that again is the misapprehension that
we’re transmitting. We’re just listening. If a signal
is there, we either detect it or we don’t, but it’s not
as though we’re advertising ourselves to the universe. Or putting
it another way, we are advertising ourselves inadvertently through
leakage of our radar for instance.
It’s also true that the space involved in searching is so large
and the distances are so great that with our present receiver capability
we would not be able to detect the leakage from Earth even at the
distance of the nearest star. For us to detect a signal, we have to
assume that somebody’s going to beam something, a beacon, a
strong transmission. If we’re just looking for an analogue of
ourselves, we couldn’t detect our twin at Alpha Centauri [closest
star system]. But we could detect a beacon, if there were one.
The other thing that I think comes out of that is frequently stated
but maybe not fully understood, that it is extremely unlikely that
we could find any other civilization at a similar level of technology
to our own. If we’re going to receive something, it will be
somebody far advanced, or very different at least.
That makes SETI exciting, but it also means that you’re very
unlikely to get a two-way conversation going. They are going to be
indistinguishable from magic in Arthur C. Clarke’s way of saying.
Sufficiently advanced technology can’t be told from magic.
’96 you became the Director of Space at Ames.
Director of Space was a wonderful title. I still have a few business
cards with that on it. I joked that it was a terrible responsibility:
if I didn’t do my job every day the planets would fall out of
their orbits, the galaxies would explode. But then NASA Headquarters
did a reorganization and created a division called the universe, and
so they had Director of the Universe at Headquarters.
to aspire to, right? Let’s talk about your role in the development
of the NASA Astrobiology Institute, which was established in 1998
When we developed the concept of astrobiology and wrote the 
Astrobiology Roadmap, we already had in mind to have an Astrobiology
Institute. This is a different kind of institute from what people
mostly had at that time, which we call bricks-and-mortar institutes.
The idea traditionally would be if NASA is going to take up a new
exciting field like astrobiology, then they should build a building,
a laboratory. They should hire people. Or maybe they should contract
it to a university. It should have a single organization. Take the
Lunar and Planetary [Institute] in Houston as an example.
We said, “No, we don’t think that’s necessary.”
First of all it takes a long time to build a building and hire people
and create a new institution. But more to the point, if we’re
on the cutting edge of science, then we’re going to presume
that the experts are primarily in universities and they have graduate
students and postdocs. So it’s much more intelligent and cost-effective
to learn how to utilize the talent in the universities than for NASA
to set up its own organization.
Hence virtual institutes. The NASA Astrobiology Institute was the
first one. Later we established the Lunar Science Institute (where
I was the founding Director) and then the Exploration Science Institute.
I think NASA’s virtual science institutes have been very successful,
and I’m proud to have been part of the concept not only for
astrobiology but as a way of doing business. It is obviously less
expensive to accomplish things through existing organizations like
universities, and if you want a university to do some serious work
in astrobiology you probably don’t have to pay for their faculty,
just give them enough to have a lab, to bring in postdocs, teach students,
something of that sort.
The idea was to solicit competitive proposals for five years for organizations
to become part of the Institute, although they would remain in their
own place. We asked for those organizations to be multidisciplinary
and geographically diverse.
We wouldn’t just take one university in one town and say, “They’re
going to do it.” The goal was to increase our footprint so that
NASA could have a much greater influence if it worked through the
academic universities. We wanted to try to have a NASA astrobiology
group in as many different universities as possible. I think it’s
been very successful. We developed the idea at Ames of a virtual institute,
and we have been the people who have created virtual science institutes,
and tried to work out a way for it to make sense.
You need to be competitive. You need to have a way of selecting the
very best teams, through 50-page proposals that are peer-reviewed.
But then you have the challenge that once you’ve done that,
you would like these organizations to collaborate and work together.
So they start competing against each other, and then ideally you create
mechanisms for them to work together.
One example is to fund graduate students that go to more than one
institution. That is, they may be a graduate student at the University
of Washington but then they will spend a semester or a year at Berkeley,
say. So that you will get connection between two different academic
The other problem that we’ve had to face is one I think that
everybody has dealt with who’s tried to do virtual organizations.
How do you get people to actually communicate, and better yet collaborate,
when they’re in two different places thousands of miles apart?
I think most people have concluded, as we have, that it is very difficult
to do if you have too many people trying to interact simultaneously.
When we have meetings of the different teams of the Institute, we
have a dozen or so people online at once, and that’s about the
upper limit with modern technology to get conversations going back
and forth between people. In fact, it’s actually easier if you
don’t have that many people.
The other thing I think everybody now realizes is it’s much
more successful if you’ve already had direct contact with people.
You can collaborate using video conferencing, telephone, email, but
it’s so much easier if you know the person. So you want to have
opportunities to physically bring everybody together once or twice
a year. Then remote communications work much better. That’s
been the experience at the Astrobiology Institute and the later institutes.
We had a review after 10 years of the Astrobiology Institute by the
National Academy [of Sciences] at NASA’s request, and they gave
us very high marks on productivity. Not only that we’ve published
a lot of papers, but the large number of those papers that had authors
from different institutions or different teams. So we think that was
quite successful. The Institute funding comes in a block grant to
fund a particular institute, and once the institute has been established
the team doesn’t have to send in proposals over and over.
We were really fortunate to be able to hire Baruch [S. “Barry”]
Blumberg as the first Director of the Astrobiology Institute. We already
had set up the Institute, and [G.] Scott Hubbard had been the Interim
Director for a year, and we had gone through the process of selection
of the teams. We were just ready to actually hit the road running.
Barry Blumberg, who was spending time primarily at Stanford University,
even though his appointment was on the east coast, was really interested.
He’s one of those Nobel laureates who came to the workshop that
we had to develop the astrobiology roadmap. He thought astrobiology
would be fun. He had a successful career. He was already 70 years
old, he was world-famous. He had a Nobel Prize for the discovery of
the hepatitis B virus and the development of the countermeasures,
a vaccine in particular. He said that probably he was responsible
for saving at least 10 million lives from hepatitis B. Every year
he would be invited to China, and they would fete him and practically
have parades because China had such a problem with hepatitis and he
had made such a difference to the health there.
Barry Blumberg was a wonderful guy and we all loved him and we all
really profited by his example. One of the things he did from the
beginning, that I’ve always thought was very important for understanding
the way the institutes work, is he’d tell all the PIs [principal
investigators}, “Look, you’ve each written a detailed
proposal explaining what you would like to do. If at the end of your
five years you have accomplished all you said you would and nothing
more, you will have been a failure. You are not expected to do everything
you said you would do. You’re senior scientists, we trust you.
The whole discipline is moving forward. You need to develop new ideas,
you need to work together. You’ll be judged on the basis of
your total output, not whether you did what you said you would do
in the proposal.”
Some of the PIs said they’d never heard that said before.
is an interesting way of looking at it. It’s an interesting
idea of the virtual institutes. I can see how it would be something
that would translate well. It would be something that would work well
within the system because of funding issues with NASA, bringing in
all these different groups.
Yes. Of course you have to justify to NASA that the money is well
spent and that it wouldn’t be better spent responding to individual
proposals. We think we can demonstrate that. But it’s not the
usual NASA way of doing business.
Lunar Science Institute was renamed the Solar System Exploration Research
Virtual Institute, which is a real mouthful.
Hey, you said it! I just call it the Exploration Science Institute.
simpler that way.
Yes. The Lunar Science Institute was a direct response to NASA’s
interest in returning to the Moon with humans, but even more the sudden
explosion of scientific interest in the Moon. Lunar studies had largely
lain dormant for 25 years since Apollo, although work continued on
Apollo data, especially the samples.
Suddenly this was changing. The Japanese had a satellite in orbit
around the Moon [Selenological and Engineering Explorer (SELENE)],
the Indians were sending one [Chandrayaan-1], the Chinese were sending
The U.S. had several missions. GRAIL [Gravity Recovery and Interior
Laboratory] to look at the gravity fields, the Lunar [Reconnaissance]
Orbiter, which has gathered more data from the Moon than all the other
scientific missions to that point added up, including extremely high
definition images, and such sensitivity that they can photograph the
inside of permanently shadowed craters just from starlight on it.
The Russians were interested, although they didn’t quite get
their mission up. Here at Ames we had the mission [LCROSS] to crash
a spacecraft into the Moon, into one of the permanently shadowed craters
near the pole, to see if there was water ice, which was very important
for the long term perspective of lunar resources.
All those things came together in a Lunar Science Institute which
was doing brand-new things just the way the Astrobiology Institute
had. Many scientists had almost forgotten the Moon and suddenly here
it was and we especially were encouraged by the students who could
vote with their feet. The number of graduate students who went into
astrobiology or went into lunar science, the number of theses on astrobiology
or lunar science. The fact that the students formed their own professional
organizations—LunarGradCon for instance was a Lunar Graduate
Student Conference held every year. They did some interesting things.
Because it’s multidisciplinary, they were willing to step up
to the fact that they needed to learn multiple disciplines, to actually
take courses in different departments. In order to stimulate the conversation,
because science is full of jargon, they did some innovative things.
When they would have the student meetings, just students talking to
students, everybody in the audience would be given a red card. If
the speaker said something or used terminology they didn’t understand,
anybody who didn’t understand would put up the card. If only
two or three people did, the speaker ignored it. But if half the people
put up the card, then the speaker knew that she should stop right
then and define those terms. It really helped give them the idea of
being able to talk to a broader audience. That surely would carry
over also to public communication.
of public communication, you were one of the first scientists to warn
the public about asteroids or near-Earth objects and the possibility
of them hitting the Earth and having obviously consequential effects.
Let’s talk about that, in 1989, you co-wrote Cosmic Catastrophes
[with Clark R. Chapman].
Yes. This is something I have devoted a great deal of energy to in
the last 20 years. I find it fascinating scientifically, but also
in terms of understanding risk and how to communicate risk with the
public. When Clark Chapman and I wrote the book Cosmic Catastrophes
in about 1988, we devoted two or three chapters to what we thought
was one of the more plausible catastrophes -- impact of an asteroid
with the Earth.
That of course was something that had become popular because of the
revolutionary discovery of the Alvarez team [Luis W. and Walter Alvarez]
that it was an asteroid impact that had caused the extinction of the
dinosaurs at the end of the Cretaceous Period, 65 million years ago—one
of the largest mass extinctions in history.
A few years later, when one of the TV programs discussed 10 things
that could kill the Earth, asteroid impacts was number one on their
list, because it had actually happened, and we know that it could
happen again. When they did a similar program five years later, asteroid
impact was not number one, it was number two. Number one was global
warming. The argument there was not that it had happened millions
of years ago, but it was happening now.
This book by Chapman and Morrison, Cosmic Catastrophes, a simple little
trade book, didn’t sell terribly well, but it was okay. We were
proud of it. I was going around giving some talks, and I was invited
to give a talk in Washington at the Congress to the space group there,
primarily of staffers, but a few members. I gave this talk about Cosmic
Catastrophes, about the asteroid impact in particular.
Clark Chapman and I had carried out the first quantitative estimate
of the risk. That is, what is the chance that it will say on your
tombstone that you were killed by an asteroid? That meant looking
at the whole range of asteroid sizes and what kind of damage they
We recognized that a meteorite, a small chunk of rock falling from
the sky, is not a big risk. Things have to hit with cosmic velocity
in order to have enough energy to produce a huge explosion. If I were
standing somewhere and 10 feet away a meteorite hit, the worst it
would ever do is just splatter me with mud. But if something could
come down with cosmic velocity, it would produce an explosion.
We had to decide the question of when an impact would not just be
a local problem but global, as the end-Cretaceous extinction event
had been 65 million years ago. Obviously to produce a mass extinction
you have to affect the whole Earth.
We had researched that, and we for the first time had a quantitative
estimate of the risk. For instance, one of the things that we said
that was widely publicized was that your chances of dying from an
asteroid are similar to your chances of dying from an airplane crash.
Airplane crashes don’t actually kill very many people. The risk
is very, very low. But everybody who’s been on an airplane bouncing
along has had a white-knuckle experience or something to make them
realize, at least think about, their mortality. We were saying, “Think
about your mortality in terms of asteroids.”
I gave this talk to the congressional people. They were interested,
and they—also encouraged by the AIAA [American Institute of
Aeronautics and Astronautics]—said, “We think this should
be seriously studied.” They wrote into the 1991 NASA Authorization
[Act] that NASA should carry out two studies of the hazard: the risk
of asteroid impacts, and the technology that could be used to protect
I was appointed to head the NASA study on the risk. I was given free
rein to do what I wanted. So I brought in half a dozen people from
other countries as well as U.S. experts. We spent about a year debating
it and ended up writing what we called the Spaceguard Report [The
Spaceguard Survey: Report of the NASA International Near-Earth-Object
Detection Workshop (1992)].
We understood that the mitigation approach must include surveys, because
we knew we had to find the objects. If you couldn’t find the
object, no other form of defense or mitigation made any sense. We
wanted to define what that survey would be and what its requirements
would be, what size asteroids should be found, how many of them.
We named it the Spaceguard Survey after Arthur C. Clarke, who in his
 novel Rendezvous with Rama, at the very beginning where he
was describing such a system for finding incoming objects, talked
about a fictional impact in northern Italy that had wiped out Florence
and Venice and killed millions of people. It said the people of Earth
after that developed the Spaceguard program to guarantee that they
would never again be taken by surprise with an impact like this. We
thought if Clarke could write that in Rendezvous with Rama, we would
take it. We asked Arthur if that was okay, and of course he said yes.
The Spaceguard Survey was proposed to NASA, and we provided estimates
of how much it would cost. The idea is you would have to build new
telescopes and support them. Following up the first Spaceguard Survey
panel that I chaired was another in 1995 [Beginning the Spaceguard
Survey] that Gene [Eugene M.] Shoemaker chaired. I was on it, and
that was specifically trying to make a better estimate of how large
the telescopes would need to be, where they would need to be located,
how much they would cost. They concluded that a survey could be done
substantially more cheaply than we had thought in 1992. If you can
imagine a program that gets cheaper with more study instead of more
NASA finally started the Spaceguard Survey program in 1998, but NASA
took a different and interesting approach. I had always assumed that
the best way to do the survey was a top-down organization. You design
optimum telescopes, you put them in right locations, you spend the
money to have people do the observations. You bring them all together
to a central organization so that you can find and track the objects.
NASA, partly because they didn’t have a lot of money for the
survey, ended up organizing it differently. They said, “Let’s
find existing telescopes and give grants to those people to do it,
and let them figure out how to do it. It doesn’t matter if the
telescopes are not identical or if they have different detectors.
We’ll actually make it a competition. We’ll say the money
you get depends on how many of these near-Earth asteroids you discover
per year. That will be more effective than being organized top-down.”
That approach turned out to be very successful because some of those
teams are extremely innovative. The group for instance at [Steward
Observatory] Catalina [Station] in Tucson [Arizona] has located several
telescopes that weren’t being used—old telescopes or at
least old optics—and refurbished them, put them together for
a relatively small amount of money, put a focal plane system on. They
have been the most successful discoverer of near-Earth objects.
Our objective that we stated back in that first Spaceguard Report
was to find 90 percent of the asteroids large enough to cause a global
catastrophe if they hit. Not a mass extinction, but to put enough
dust into the atmosphere to block sunlight and produce an agricultural
collapse for a couple of years. We had estimated that at about one-kilometer
We said, “The goal is to find 90 percent of the asteroids one
kilometer or larger in 10 years.” Of course some people said,
“Why 90 percent, why not 100 percent?” But you never get
100 percent of anything. How would you even know that there wasn’t
one or two left? In any such system, the rate of discovery would drop
with time as you found more and more of them. You could in effect
retire 90 percent of the risk if you found 90 percent of these objects
that were capable of causing a global catastrophe. That’s what’s
happened. The survey has now found more than 95 percent.
of the things I’m assuming you found through all of that was
the  Apophis [near-Earth asteroid], that was identified in
2004 with a possible close flyby relatively soon, and then a possible
return seven years after that. Do you want to talk about that for
While the observing astronomers were out finding these objects, there
was of course a very important role for the dynamicists who calculate
orbits from observations over a fairly short window in time. Within
a month there might be three or four positional observations. Can
you calculate an orbit? You have to determine an accurate orbit if
you’re going to decide if that could ever hit or not. While
the observers were chugging away reporting several discoveries a week,
the dynamicists were trying to interpret the hazard.
One result was two superb orbit analysis programs, one at JPL and
one at the University of Pisa [Italy], that could take these observations
and determine a prediction as to whether the object might hit, and
what the probabilities were, and which objects were important enough
that you should make an effort to go back and observe them again.
JPL and Pisa check each other, and they both do this every day. Every
time a new observation comes in, they re-compute the orbit for that
It’s a huge thing really, and the results are all online. So
people who worry about, “Oh, the government is not going to
tell us if there’s something coming” just haven’t
looked at the system. You can go online to JPL and get the latest
calculations, orbits, predictions of close passages for every known
asteroid updated daily, and you can do the same thing at the University
One of the interesting discoveries was Apophis, which is a pretty
big asteroid, several kilometers across, that was going to come by
the Earth quite close. It was clear fairly early that it wasn’t
going to hit, but it was going to come as close as our geosynchronous
satellites, would be visible with binoculars, even to the naked eye
as it went past.
Then the dynamicists realized that there were several interesting
consequences. When an object comes very close to any planet, its orbit
is changed by the gravity. If the Earth’s gravity changes its
orbit in just the right way, it would come back in six years or seven
years and hit us. Not high probability, but you couldn’t say
once it went by, “Oh good, it’ll never be back.”
It’s possible it could go through what’s called a keyhole
in which the orbit would be changed just enough by the Earth’s
gravity so that it would come back.
That was a subject of considerable interest in general, particularly
for Apophis. We knew it wasn’t going to hit us the first time,
but could it hit us the second time, seven years later? It’s
taken years of observation to have enough precision to show it’s
not going to hit us the second time either.
would it have been a global catastrophe?
Apophis would have been a global catastrophe. It would have caused
so much dust in the atmosphere that you could have a global failure
of agriculture. Of course one of the questions we immediately had
to ask, “What does that mean? How much food is in storage, could
you live for a year on what’s in your refrigerator or your freezer?
Could the world?” The answer is no. The people that would be
best off would be places like the U.S. and Canada, because we have
a lot of food in storage and on the hoof. If we slaughtered all of
our herds you could get meat that way. But places near the equator
where they depend on two or three rice crops a year, they don’t
keep much stored at all. Even losing one of those crops or losing
two of those crops in a row would have a devastating problem in terms
of famine. Then you assume that the consequences of famine might be
pandemics, might be mass migrations, could be wars. You could have
a collapse of civilization.
Clark Chapman and I tended to call this size threshold of a kilometer
or so for global consequences a civilization-threatening impact. The
effect would be global. The impact may have been localized to someplace
like the size of a state in the United States, but if the actual physical
impact caused agricultural failures around the world, then everybody
had to worry. You couldn’t just talk about defense as, “Let’s
defend the U.S.” You had to worry about defending the Earth.
one of the articles you sent me, in 2015 you were in Italy. They were
doing a what-if scenario to run through what would happen. Do you
want to talk about that and what they learned from that?
Yes. There has been an International [Academy of Astronautics] Planetary
Defense Conference six times now. It’s been going over for 15
years or more. I’ve been on the organizing committees of each
of those. They’ve gotten bigger and bigger. It is an international
issue, and now it’s an issue that’s important at the UN
[United Nations] also.
One of the things we did, as an education for ourselves and also for
the public, is to say, “Okay, we can talk about all this. We
can talk about discovering an object and predicting where it’s
going to hit and understanding how we might protect ourselves, but
what would be the actual timeline for that?”
We did an exercise in 2015—and we’re doing one again this
year, a week from now in Tokyo. The folks at JPL, who are so good
at orbits, generated a dynamically realistic orbit for an imaginary
object that would come very close or hit the Earth, and examined what
the observing opportunities would be. How quickly would you be likely
to get enough information to have a firm prediction that it would
hit or where it would hit?
We condensed all that into a week. Every day they would give us an
update, “Three years have passed since the last one.”
At first all you know is the asteroid has a 1 or 2 percent chance
of hitting somewhere on the Earth. Then, as that probability either
goes away or goes up—but of course for the exercise it went
up, although in the real world most of the one percent objects are
going to miss—then you would find out that there was an impact
It’s a little esoteric, but the intersection of the orbit of
the Earth and the orbit of the asteroid tells you where the two would
intersect, a line around the Earth. It still wouldn’t tell you
where it would hit, but you could say it would hit on this path. In
this case the path (impact corridor) started in Iran, and then looped
around the Earth all the way out into the Pacific [Ocean] crossing
a number of major cities, like Delhi [India] and Beijing [China] and
Then we tried to guess, as the information about the asteroid’s
size and composition improved and the risk corridor shortened, what
the response of humans might be. We were a bunch of scientists, for
goodness’s sake. What do we know about this? But it was an interesting
exercise, because you actually sense, even though it was all condensed
into a week, the progression of knowledge.
At one point for instance it looked like the asteroid would hit somewhere
between the South China Sea and north India. Of course there’s
a huge difference in population between hitting in the sea and hitting
in north India. Both India and China are countries with relatively
mature space programs, and the question is, would either of them try
to deflect it into the other country? China would much rather it hit
in India than the South China Sea, and India vice-versa. It made for
an interesting discussion.
But then of course we had to say over and over and over to the press,
“This is purely hypothetical. There is no asteroid coming, there
is nothing going to happen. We are not experts in what the response
of individual countries would be.”
the radio broadcast in the ’30s [Orson Welles’ The War
of the Worlds (1938)].
Yes. We always have that problem, that communication problem. You
can go to the JPL website for instance that lists every known asteroid
and see which ones are coming close. There is apparently a group of
people who want to create almost continuous scare stories about an
object going to hit. They publish in what I call “newspaper
tabloids.” They publish in several British tabloids, India produces
some of these. And they generate “fake news” on the Internet.
With communications now, even when some obscure newspaper in India
announces that there’s going to be an impact and we should all
be scared of the end of the Earth, it goes around on the Internet.
Fortunately not so much of it in the U.S. NASA generally ignores it,
properly, because such stories are all absurd, they’re absolutely
fiction. But they constantly keep in front of some element of the
public that asteroid impacts are possible.
know part of what you’ve done and what Carl Sagan did—he
was interested in being a “baloney detector” as I think
you put it in a paper you were writing about him. He fought against
what he called pseudoscience.
I know you have a program that you’ve worked on a lot, Ask an
Astrobiologist [blog]. You’ve also had to debunk a lot of false
scientific claims, about for instance the end of the world in 2012.
How did you first become that person here at Ames to answer these
I’m sure that Carl Sagan did influence me in feeling that it
was a responsibility of scientists to communicate not only the good
things we do but also to counteract the falsehoods. The one that dominated
over all the others was the story that the world was going to end
on December 21st of 2012, when we would be hit by a fictional planet
Nibiru. It was tied to all sorts of utter nonsense about the Mayan
[Mesoamerican civilization] calendar, and the things that were said
about the Mayan calendar were almost all wrong. People were making
a lot of money. They would take rich people down to the former Mayan
areas in Central America and give them luxury tours and explain to
them how the world was going to end.
There was a huge boost of people building air-raid shelters, fallout
shelters, selling emergency—the whole idea of do-it-yourself,
save yourself when the world ends, became very widely held. There
were people who decided that they could publicize that a particular
mountain range in Spain for instance would be the only area not destroyed
when this planet Nibiru hit us. Of course they bought it up and sold
the lots at extravagantly high rates. Several hundred books were published,
and a big Hollywood movie called 2012. A lot of people were trying
to make money from this fear, and it really angered me. Especially
that it was such blatant misrepresentation used to scare people, and
most of all of scaring children.
I became exposed initially because of my blog: Ask an Astrobiologist.
Suddenly, even though it wasn’t astrobiology, people started
sending me questions about the end of the world. They were very disturbing.
Like a woman who wrote and said, “My only friend is my little
dog, and I’d like to know when the world will end so I can put
her to sleep so she won’t suffer.” There were kids who
wrote that they couldn’t sleep, they were not going to school,
they were throwing up all the time over fear. There were a few that
said they were going to commit suicide, and in the UK at least one
girl, teenager—did commit suicide over it.
What do you do when you get an e-mail from somebody who says, “I’m
Jimmy, I’m 11 years old, I understand the world is going to
end. I don’t want it to end, why should my life be cut off,
what should I do?” It was stressful. For about three years I
was answering questions first weekly, then daily, then as it got closer
to [December 21st] I would get questions at the rate of 10 or 20 a
day coming in.
I, in effect, became the most prominent spokesperson from the whole
scientific community on trying to counter this. I got good support
from NASA, from the public information offices at NASA Headquarters
and here at Ames. No one said it was foolish of me to do this, and
I was definitely on the point of the spear in terms of dealing with
you feel like you were able to convince these people after talking
Some of them certainly. Most of the time you don’t end up with
a two-way conversation, but sometimes you do. There were 13-year-old
kids who wrote back and said, “Thank you. Thank you, I feel
so much better now.”
Kepler [space telescope (launched 2009)]—you were instrumental
in helping to sell that idea so that the funding would be available.
That seems to be something that has to be done with the NASA budget
a lot, especially for missions. Do you want to talk about that experience?
Sure. Every mission has to be marketed. It has to go through a lot
of study to refine your understanding of what you’re going to
do enough to get a funding line. NASA has basically two kinds of missions.
There are the missions that are run by NASA, often by JPL or Goddard
[Goddard Space Flight Center, Greenbelt MD]—Voyager and Galileo
and the Hubble Space Telescope were examples of this—and now
increasingly there are also missions that are proposed by individuals
or individual centers which are smaller cost. They involve an actual
formal proposal evaluation.
The big missions will do competitive selections for the instruments
on the spacecraft, but not the spacecraft itself. But more and more
we’re doing these things like Discovery [Program] that is PI-led.
Here at Ames we have a wonderful PI, Bill [William J.] Borucki, who
for 20 years had been trying to sell the idea that we could discover
planets around other stars by measuring with high precision the brightness
of the star. When a planet passed in front of the star, if the orbit
were aligned properly the brightness would drop, but only a very small
It turned out it was such a small amount that except for large planets
and small stars it couldn’t be done from the ground. The noise
caused by the atmosphere made that kind of precision photometry impossible,
so it needed to be done from space.
Bill had gradually developed the idea. He ended up doing five Discovery
mission proposals to NASA Headquarters altogether before his mission
was finally selected. Each time they would say, “Well, an interesting
idea, but the technology isn’t mature, or you need to go back
and study this.” He would just roll up his sleeves and start
all over and do it again.
Borucki was in the Space Science Division when I was head of it, so
I came to Ames at a time that he would have already gone through a
couple of these proposals. I had heard him give talks to NASA panels
advocating this. I thought it was a wonderful idea, but I was very
skeptical of the practicality of it, because you would have to observe
an awful lot of stars.
Only on average 1 star in 100 would have its planet orbits oriented
properly. If you wanted to find 10 extrasolar planetary systems you
would need to observe 1,000 stars, and 10 probably isn’t enough
because not every star will have planets. If only a few percent have
planets, then you’d have to observe tens of thousands of stars,
and that’s very difficult. Simultaneously observe 100,000 stars
with sufficient precision to detect a drop in light when a planet
passed in front. These are planets you cannot possibly see. You could
say you see their shadow or you see their effect on the light of the
As Bill Borucki developed these ideas, with some colleagues here,
I said, “We really ought to see if this is practical. We really
want to make this happen. It would be so exciting. There is no other
program that NASA could carry out that would answer the question of
whether there are planets around other stars.”
I put together a panel chaired by Jill Tarter of the SETI Institute
with some really, really good astronomy experts, photometry experts,
to do a careful query of Borucki and look at his plans and see what
they thought of it. They spent a couple days, and they were really
good. They were asking all the hard questions. He was answering them.
They came out—this is a nonadvocate panel—saying, “We
think it can really happen. We think it’s good.” That
made me believe it more than I could just trusting my own judgment,
and I made sure that report was circulated at NASA Headquarters and
to the science community.
Then a year or so later, the thing that they still were uncertain
of was the stability of detectors, because you’re having to
measure such small changes in brightness. So NASA Headquarters gave
us $500,000 and Ames put in another $500,000 from the Director’s
discretionary funds to do a laboratory setup to mimic the photometry
system and try to prove whether the detectors were stable enough.
At this point I started talking to people at Headquarters about it.
I talked to people in the Planetary Science Division and the Astrophysics
Division. Eventually, once I became Director of Space here, I had
access sometimes to Dan Goldin, the NASA Administrator. It wasn’t
much, but he came to visit Ames every few months, and I made sure
each time he was here at Ames I at least got to give him an elevator
speech. Not a full-up presentation, but just say, “Hey, Dan
this really is a great idea. Our testing is going well. I really think
that this could be something outstanding for NASA’s future.”
I’m sure there were lots of other influences, but I felt as
though if I could only say one thing to the NASA Administrator on
these visits it would be to push Kepler. Kepler was ultimately selected
and flew, and has been in many ways the most remarkable mission NASA
has ever done.
It is hard to compare Kepler with a mission like Cassini to Saturn
or New Horizons to Pluto, but the fact is that it’s fundamentally
changed our understanding of ourselves in the universe. When people
talked about SETI or looking for life elsewhere on other planets it
was frequently felt that the solar system was probably very unusual
and maybe only 1 star in a hundred or 1 in a thousand would have a
planet, something like that.
Kepler has shown that when you look at the night sky and look at the
stars, almost every star you can see has at least one planet. If there
are 100 billion stars in our galaxy, there are probably 200 billion
planets. That is a revolutionary discovery. We still have to do a
lot to understand them or to characterize them, but we now know that
planets and planetary systems are the rule, not the exception.
been a lot in the news about discoveries in the TRAPPIST-1 [dwarf
star] system, then the latest announcement by NASA a few weeks ago
about Saturn’s moon Enceladus.
We sometimes call it Enchilada.
to say—about the possible hydrothermal activity on the subsurface.
When you go back a few years, Voyager has gone so much farther and
now is in interstellar space.
When all of these things were being developed, and all of these programs
like Cassini and Kepler—everyone has hopes that things will
work the way they’re supposed to work, but has it changed your
ideas about what’s out there?
It’s changed my ideas, but not in a linear progression. When
I started forty years ago with Viking, two landers on Mars, two orbiters,
were followed in very short order by two Voyager spacecraft, which
went to Jupiter and Saturn and Uranus and Neptune. We were having
these experiences of data just flowing in. I thought that’s
what planetary science was going to be like, I thought there’d
be big missions every couple years.
Then it really all fell apart, partly because of the Shuttle and the
Shuttle accidents, but we didn’t go back to Mars for 20 years.
We didn’t have any follow-up to Voyager except Galileo. Then
it was delayed, and then its antenna broke. We sent two missions to
Mars and they both failed in the same year [Mars Climate Orbiter and
Mars Polar Lander].
I went through a period of thinking that we’re going to have
telescopes, we’re going to have things like the Hubble [Space]
Telescope, and that’s great, but the planetary exploration has
really almost stopped. It’s now taking us so long, 10 years
at least, to develop a mission. If it’s going to the outer solar
system, it takes more years to get there.
Then, in the last few years, we are having a second golden era of
planetary exploration. Five spacecraft to the Moon, for goodness’s
sake, each one of them far more capable than anything we had back
in the Apollo era in terms of orbiters.
Landers—China landing on the surface of the Moon, going to bring
back samples from the lunar far side. India has a very successful
lunar mission, Japan a successful mission. Japan has also had flights
to near-Earth asteroids that and landed on the surface and brought
back samples [Hayabusa mission]. The European Rosetta comet mission
was spectacular. Kepler of course is magnificent.
So suddenly we’re in an era of really rapid discovery again,
and I think that’s wonderful. I’ve lived long enough to
witness the first golden era, then 20 years when we were not accomplishing
as much as we thought we should have, and now another golden era.
you have any worries about the political feeling of the time and some
of the skepticism about science that we’re hearing more now?
Do you have any worries that these programs are going to be cancelled?
I know in the [president’s] 2018 budget the landing on Europa
looks like that’s something that would be canceled. There’s
some different things that they’re talking about canceling.
So do you have any worries that we’re going to go into another
one of those periods?
I always worry, I always worry. Given the situation in the Congress
it’s hard to have much faith that they’ll do the right
thing, but often they end up doing the right thing. It’s Congress
that’s pushed a Europa mission. Although they aren’t funding
directly the Europa lander, I think it’s coming along.
There’s tremendous interest in Saturn’s moon Enceladus.
The New Horizons at Pluto was a fabulous mission. Compared to other
things, these are not expensive, they really aren’t. They’re
way down relative to almost any other government program in terms
of funding. I have no idea what’s going to happen, but there
is no reason that we should slow down. We have a vibrant space science
I think the real questions for NASA concern humans in space, and are
we going to go that route again. A lot of people take it as a matter
of faith, and I used to, and maybe I still do, that human exploration
of the solar system, going to the Moon and then to Mars, will happen.
But meanwhile the results we’re getting are not from humans
in space, but from our deep space probes and our robotic telescopes
in space. They have been fabulously successful.
the publicity and the fact that people are aware more and more of
what’s happening, which you’ve been a big part of. Before
we close, is there anything that you would consider your biggest challenge
in your career, or anything you would do differently if you had a
In terms of doing differently, I did do one thing a little bit strange.
When I left the University of Hawaii and came to work for NASA it
was when NASA was not launching missions, and that was a disappointment.
I had hoped that I would have more mission involvement once I worked
for NASA, but there just haven’t been that many missions.
It’s a very great difficulty for young scientists, because even
when they are selected to be team members on a mission, they don’t
get the money they used to. You could be a postdoc, someone just with
a PhD, get a position on a mission like New Frontiers, and not get
enough money from NASA to pay your salary.
But I’ve done fine. I’m very pleased with it. I’m
thankful that I’ve also been involved in the struggle against
pseudoscience—and today that means primarily a struggle against
climate deniers—and that I have been able to talk to so many
people and write. I’ve written multiple textbooks that are in
use in the colleges.
One thing right now that I’m very proud of is that the college
astronomy text that has been out for 20 years by Andy [Andrew] Fraknoi
and Sidney [C.] Wolff and me [Astronomy] has just been completely
updated and put online for free. In an era when other college textbooks
cost $150 each, now a university can adopt our book, the students
can get it on their laptop free, or they can print a copy. That’s
something that’ll last, and that will help the next generation
of young people learn about astronomy and space exploration.
think that’s a good place to stop. Thank you very much.
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