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Carl Sagan, Imagination, Science, and Mentorship: An interview with David Grinspoon

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The following is a guest post from Trevor Owens, Special Curator for the Library of Congress Science Literacy Initiative. 

To most Americans Carl Sagan is a TV persona. To David Grinspoon, who knew him since he was a child, he is much more. Among other things, Sagan was a personal mentor. I am thrilled to be able to talk with David about his relationship with Carl Sagan and the items from The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive  online collection.

David Grinspoon is a Co-Investigator for the NASA Astrobiology Institute, adjunct professor at the University of Colorado, a widely published writer, and currently serves on the Science Team for the Curiosity Rover mission to Mars. He is also, the inaugural Baruch S. Blumberg NASA/Library of Congress Chair in Astrobiology at the Library’s John W. Kluge Center. Aside from that, David is also a winner of the Carl Sagan Medal for public communication by the American Astronomical Society.

Trevor:  You knew Carl Sagan personally; he was an early supporter and mentor in your interest in astronomy and your work in planetary science.  Could you tell us about your early experiences with him? What do you know about him that others might not know?

New Years gathering at the Grinspoon's Wellesley home. Eight-year old Grinspoon is seated in the chair and Carl Sagan is in the foreground. Photograph by Lester Grinspoon. Used by permission from David Grinspoon.
New Years gathering at the Grinspoon’s Wellesley home. Eight-year old Grinspoon is seated in the chair and Carl Sagan is in the foreground. Photograph by Lester Grinspoon. Used by permission from David Grinspoon.

David: I first knew him as a close family friend from when I was about 6 or so.  It was the mid-1960s, before he became famous.  He was “Uncle Carl” and was very close to my parents, pretty much a member of the family, so he was around the house a lot. Our families went on vacations together and his sons, Dorion and Jeremy, were some of my closest friends.  He was like a favorite uncle who had a cool job and told us elaborate bedtime stories- The most memorable was a serialization that I guess he was just making up on the spot, with installments that seemed to go on forever, a swashbuckling saga revolving around a central character who was, I think, the seventh best swordsman in France.  This was a while ago – the details might be wrong- but I remember the feeling of adventure and romance in the story. 

Many early memories are just typical family things like playing Frisbee on the beach at Cape Cod, but others seem more significant now, such as going with Carl when he spoke at Harvard Observatory’s public observing night, where we got to look through telescopes and hear him talk about astronomy.  Once he took us kids along to give a talk at a planetarium and we got to go behind the scenes afterward and work the controls- move the universe around.  One vivid memory is of going together to the Boston premiere of “2001: A Space Odyssey” and the conversation afterwards with Carl and my father (a physician) discussing the (very few) scientific mistakes in the film.  That whole experience, the film and the surrounding discussions, pretty much blew my young mind and induced both scary nightmares and beautiful daydreams about space and the future.

So many other memories emerge at random in response to your question.  Once when we were staying at Carl and Linda’s condo in Ithaca, he had his astronomy students over to the house for an evening lecture and dessert.  We were allowed to listen in as long as we kept quiet and didn’t roughhouse.  The slides of galaxies and nebulae, and Carl’s tour through the Cosmos for his students, were all so completely mesmerizing.  That was another night when I had trouble sleeping! 

Photograph by Lester Grinspoon of Carl Sagan and David Grinspoon having a conversation by the pool. Used with permission by David Grinspoon.
Photograph by Lester Grinspoon of Carl Sagan and David Grinspoon having a conversation by the pool. Used with permission by David Grinspoon.

He engaged in respectful arguments with the kids – he took our ideas seriously.  Once we got in an argument about rock music vs. classical.  Typical 70s generation gap stuff.  He said that comparing  a great rock song to a symphony was like comparing a simple cartoon to a great painting.  I wish then I had known about styles of art, like  Japanese paintings, where a simple gesture is deep and sophisticated.  I would have had a better retort.

When Carl started to get famous the strangeness was something we often  joked about . Like one time at Cape Cod I was playing guitar and singing “Me & Julio Down by the Schoolyard”, got to the line “We was all on the cover of Newsweek” and we all cracked up because it was the week that Carl was on the cover of Newsweek!

Another random memory that gives a glimpse into the world of Carl happened in the summer of ’79 when I was working as an undergraduate research assistant at JPL .  Carl was on the Donahue Show and he wanted to use this beautiful scale model of the Voyager spacecraft, but JPL would only let him if someone personally escorted the spacecraft model there on the plane.  So I was given the job of taking it to Chicago. (Could you imagine trying to take that thing through TSA security today?  Forget it.  You’d be on the permanent full cavity search list.) I brought it to the studio for the filming and when I walked with Carl down a long corridor, past where the studio audience was lined up, you could hear and feel a wave of excited attention pass down the line as people noticed him – this holographic sound wave of 400 people simultaneously whispering “there’s Carl Sagan” followed us down the hall.  Surreal. 

“What do you know about him that others might not know?”- – He was a really excellent ping pong player, liked to sleep late, worked almost all the time, had a very good sense of rhythm and an endearing staccato laugh.  And of course what people sometimes forget about people who become icons, as you can surmise, he was a human being. Obviously he was an extraordinary individual and often in private he was even more sparkling, brilliant and fun than in public.  But he was an actual person and so, like all of us,  had moments of being dumb, petty and wrong.   It’s a little amusing now to see him becoming a sort of secular saint.  With all the Internet memes, video mashups, and all.  Even rational humanists need their quasi-religious characters to worship and Carl is certainly a good candidate, but I do sometimes wonder what he would think of all that?  I observe the ongoing apotheosis of Carl with some eye-rolling as well, remembering with a chuckle a few less sanctified moments.

Trevor: We can now read a rough draft of Sagan’s novel Contact  and listen to some of the tapes from his original dictation online.  It is fun to get a bit further into the back story of fictional characters.  For example, Sagan took an experience from your life and wrote it into the experience of the main character Ellie Arroway. Can you tell us about that?

Carl Sagan's inscription in David Grinspoon copy of Contact. Used by permission from David Grinspoon.
Carl Sagan’s inscription in David Grinspoon copy of Contact. Used by permission from David Grinspoon.

David: I was in Hawaii in 1984 (during grad school) for a conference.  This was my first trip to Hawaii and my first-ever talk delivered at a professional conference.  The evening after my talk (a time of massive relief) I was exploring the Big Island with some friends. We were on the flank of Mauna Kea in a spot where you can see the ocean to the East and the West, watching the sun set into the ocean 10,000 feet below, and watching for the green flash.  Someone mentioned that it was a full moon. So, I turned and caught the moon just rising out of the ocean directly opposite the setting sun. I could see both on the horizon at the same time!  All of a sudden I had a powerful, visceral feeling of the Sun and Moon as stationary points in space, and the Earth below me, inconstant and turning.  I was the fool on the hill, no longer seeing the sun going down, but instead feeling the world spinning round. It was the diagram we always draw to explain the “illusion” of a sunset, but right then the illusion reversed and I was there, feeling it spin. A moment of truth.  Literally, a moving experience. I nearly fell over.  Then I did fall over, laughing with joy.

A couple days later, we were at Carl’s hotel room to watch the Vice-Presidential debate between Geraldine Ferraro and George Bush (Carl, very famous by then of course, stopped at the hotel store to buy some diapers for his daughter and I remember him saying “I’m not ashamed to be seen walking through the lobby with a pack of Huggies”.  Is that TMI?). Sometime over the course of the evening I told him about my moment on the volcano. I had no idea that it had registered until I received my inscribed copy of Contact saying “To David Grinspoon who inspired pages 16-18”.  That’s where young Ellie has a formative experience of seeing the stars and planets set through the trees and powerfully realizing she is on a spinning planet. How cool that Carl integrated my experience into his character, and chose to tell me about it!  Of course all fictional characters are amalgams of people in the author’s life, and it’s fun to know that in some small way Ellie Arroway is part me.  She is also a familiar character from the community of planetary astronomers both Carl and I worked in and, in particular,  the women who’ve had to be that much more excellent and determined to get recognition for their achievements.

Trevor: In an exchange of letters with Sagan during your first semester of college you mentioned H.P. Lovecraft’s speculative fiction.  Could you tell us about conversations you had with him about the roles that science fiction and imagination play in science? What do you think he thought the connection was? How is science fiction relevant to you now in your work as a scientist?

A note with a draft of The Dragons of Eden sent by Carl Sagan to David Grinspoon.  Photograph used by permission from David Grinspoon.
A note with a draft of The Dragons of Eden sent by Carl Sagan to David Grinspoon. Photograph used by permission from David Grinspoon.

David: Carl was a big fan of classic science fiction and he had friendships with many of the authors, in particular those who wrote “hard science fiction” that was grounded in real science and fact-based speculation. In Carl’s world there was a lot of crossover between the two.  Several times when I was a kid I got to hang out with Carl and Isaac Asimov (talk about nerd-kid heaven!), who knew more science than just about anybody on the planet, but eventually became known mostly for his science fiction.  As a kid I became a total SF geek.  It started in the 5th grade with Asimov’s Lucky Starr series of what would now be called “young adult” novels of adventures in the solar system.  I think Carl was delighted that I got so into it, and he was always recommending books and stories. He turned me on to lots of great stuff and I think, in later years,  I returned the favor.   He once sent me a copy of “Microcosmic God” by Theodore Sturgeon, which he described as one of his favorite stories.  It concerns a scientist figuring out the origin of life, and then duplicating it in his lab and creating a new form of life – an experiment that eventually (of course) gets out of control.  (One of the substances the scientist gives his life forms to accelerate their development is tincture of cannabis!)  Of course one of Carl’s scientific obsessions was the origin of life and what conditions it might have required on early Earth and elsewhere in the universe, and his laboratory at Cornell, where I worked summers in college, was largely directed at duplicating these conditions.

Certainly for me as an astrobiologist science fiction has played an important role.  One of the quandaries of our field is that we are trying to study and search for something – life – that we can’t define in a rigorous way.  We only have one example of a biosphere so we can’t really give a good definition.  But in order to search we need provisional definitions.  How do we know we are really looking for something universal, and not just another version of ourselves? For this purpose of thinking outside the box of our biases and preconceptions, serious science fiction has been tremendously valuable. What if life is not carbon based?  Can life exist as a gas or a plasma?  Could planets or stars in some sense be alive?  What about an interstellar cloud?  Could life exist on such a small or large scale, or move so fast or so slowly that we wouldn’t recognize it?  Could you have an intelligent virus?  The list of questions goes on and they’ve all been explored in science fiction.  As scientists we are fed by this literature and.  in turn.  I think the best SF writers are very aware of what we, in the scientific community,  are doing, thinking and discovering. Carl, famously, wasn’t afraid to speculate, and he felt that science and science fiction had a symbiotic relationship, each stimulating ideas in the other. 

Trevor: Sagan wrote many letters of recommendation for you over time; your undergraduate application to Brown, your application to doctoral studies at the University of Arizona, and your application for an appointment at the University of Colorado. In each letter he focused on different aspects of your work and character. Could you reflect on what they mean to you? What do you think these letters say about what Sagan thought were the important characteristics of an astronomer?

Carl Sagan recommends David Grinspoon for admission into the undergraduate program at Brown University. From the The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive.
Carl Sagan recommends David Grinspoon for admission into the undergraduate program at Brown University. From the The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive.

David: Wow, it’s an emotional experience reading these now – little flashes of our relationship at these branching points that remind me of the somewhat unusual trajectory Carl followed through my life: from family friend and surrogate Uncle to teacher, advisor, mentor, and then colleague. And this part is a little embarrassing, I guess in the way that it’s sometimes hard to take compliments, and here are pages of them. Carl’s generosity is moving and from him, along with my other excellent mentors, I learned about science Karma. Now I get a constant stream of requests to write recommendation letters for students and young scientists and I try to emulate this kindness and eloquence. The college admission letter written in 1976 mentions that he’s known me for the last 10 years – which dates to when I was 6!  And it conjures memories of the Viking landing; staying with Carl, Linda and Dorion in their condo in Pasadena and watching the first enchanting pictures from the Viking 2 site come down at JPL;  and the first reactions to, and conversations about, that rock strewn vista which is now burned into the retina and brains of all planetarians.  But I can’t believe he describes me as an accomplished tennis player.  My one tournament I lost in the first round! 

The grad school letter to Arizona – again this contains passing references to so many peak formative experiences – the summers at Cornell and Pasadena where I learned how to do science, but also ran around following the Grateful Dead and learning so much about life. One thing this reminds me of is how much I wanted to please Carl.  I think he brought that out in a lot of people.  For example in ‘79 at JPL, the summer of the Voyager Jupiter encounter, he asked me to get him a solar spectrum at a certain resolution and in some units such that, in order to really do it right, required understanding some quantum physics and mathematical conversions that I didn’t know how to do. But I wasn’t going to tell him that. So I went to the Millikan Library at Cal Tech and chased down all of these books and papers and taught myself some obscure math so I could figure it out and write him up a good report. I think I gave him a little more than he was expecting! You can see that Carl thought that a planetary scientist, no matter what their specialty, should be steeped in physics and math.  It makes me wonder if he would be skeptical of the way some astrobiologists are being trained today – very broad but perhaps not as deep and grounded in the basics as he would want.

The faculty recommendation letter reads as more of an evaluation of a junior colleague, rather than a student. (By the way, the year on this has to be a typo.  In ’88 I was still in grad school, and had definitely not yet applied for this position!)   At the time he wrote this I was working as a post-doc under Jim Pollack, who had been one of Sagan’s first grad students, but by then was an accomplished and renowned senior scientist.  Jim and I were working on models of the clouds of Venus that built on earlier work that Carl had done with Jim on the greenhouse climate of Earth’s sister planet.  I could do a much more sophisticated job with new spacecraft data and bigger computers than they’d had access to.  During that time we were working together, the first radar images of the surface of Venus were released from the Magellan spacecraft, and when I saw them I knew immediately that Venus had a strange volcanic history that was probably part of the climate story.  This idea became the focus of a decade of work that was then built on, in much more sophisticated fashion, by a student of mine, Mark Bullock, who started working with me right as I finished up with Jim and started the faculty job that this letter refers to.  So this serves for me as a time-lapse view of the progression of stages in the life cycles of scientists and mentors, and makes me aware of the succession of generations in science. (cue “Sunrise Sunset” from Fiddler on the Roof!)

Trevor: In addition to his role as a science communicator Sagan mentored many scientists over the years, including you. In this letter  he offered detailed feedback for your doctoral thesis. How do you feel about Sagan’s role as a mentor to you?  

Carl Sagan offers detailed feedback to David Grinspoon on drafts of three chapters of Grinspoon's doctoral thesis in planetary sciences from the University of Arizona. From The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive
Carl Sagan offers detailed feedback to David Grinspoon on drafts of three chapters of Grinspoon’s doctoral thesis in planetary sciences from the University of Arizona. From The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive

David: Oh man its amazing to see this again after so many years, and when I read this now it triggers the same mix of reactions: great appreciation for the time and effort and attention, mixed with a few grimaces!  As I was when I first received this, I am struck and impressed by the level of detail.  It’s an interesting mix of points on content and style.  He was concerned with both.  I remember him correcting my pronunciation of certain phrases like “Rayleigh scattering” – Carl saying, emphatically “Rah –lay is a kind of cigarette, it’s RAY- LEE”!!  (This worked.  I say it correctly now and when I hear someone pronounce it wrong I hear Carl’s correction.) And I see that, as a mentor, he wanted me to learn how to do science but also to learn how to present myself to the world in the right way.

He taught me a lot about his approach to scientific problems and to some degree I picked it up.  Some of my professors in Grad school at the University of Arizona accused me of picking up on it too much – that is, they complained that Carl simplified problems too much to get quick results.  But there is a real art to knowing when a simplified treatment can give you a useful answer.  To give a random example-  for part of my thesis work I was constructing a climate model that could simulate the temperature and illumination effects of arbitrary amounts of dust in different layers of the atmosphere, so that I could model what would happen to an Earthlike planet if it got bombarded by a large number of asteroids or comets in a small period of time, such that the dust raised from one impact would not have time to fully settle before the next one came crashing in.  I wanted to see how the climate would be affected by a constant pall of dust with the amount fluctuating as a result of big impacts.  I was visiting Carl in his office at Cornell and he asked how this work was going.  I told him that I was frustrated by the complications of modeling correctly the way the dust altered the radiation filtering through the atmosphere.  He pulled out a pen and paper and said “look if you’ve got such and such a mass of  dust, and the average dust particle is this size, and its got such and such a cross section, and so on, then you just multiply this by that and boom there it is. What’s the big deal?” (or something to that effect)  And I knew that my professors at Arizona wouldn’t approve of the simplification because it neglected multiple scattering, and non-grey radiative effects, and blah blah blah, but I also knew that Carl’s approach would yield some decent approximation of the right answer, with months less work than the method I had been wrestling with.  It was interesting to see him so calmly and methodically explain what seemed to him to be the obvious approach.

I wrote up an abstract for a talk I was giving on these results at a meeting in Helsinki – actually my first ever invited talk at an international conference so it felt like a big deal – and Carl was my co-author.  When I ran the abstract by Professor Don Hunten, a  towering figure at Arizona who we were all afraid of (he had after all, invented much of the modern theory of planetary atmospheres, and he did not suffer fools gladly), I handed it to him and said “I’d appreciate if you could read this, though I’m worried you might think its crazy”  He took one glance at it, cleared his throat and said “Well, considering who the two authors are, I wouldn’t be surprised.”

I think partly due to Carl’s influence, I found myself searching for problems that could be solved in elegant and simple ways – low hanging fruit in terms of the complexity and effort, but you have to be smart and really up on the literature to know when such an approach can yield a worthwhile result.

Trevor: You have shared your education and experiences in college as part of your relationship with Sagan.  The Library has his freashman year college notebook. He was 16, and it was the early 1950s in Chicago. Could you pick out a page and talk about what it means to you?

Carl Sagan's University of Chicago undergrad notebook. From The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive.
Carl Sagan’s University of Chicago undergrad notebook. From The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive.

David: Oh, what a treat to look through this notebook!  The handwriting is very familiar – tiny and hard to read!  And, my God, what a complete and total nerd he was!  And I mean this in the most affectionate and self-identified way.  Unlike any of the other materials you’ve asked me about, this is the first time I’ve seen anything like this. And of course it comes from a time way before I knew him, from before I was born.  But its all Carl, that’s for sure! 

Really, it’s an incredible experience to read through these. It reminds me of myself as a teenage science geek and how good it felt when he asked my opinion on something he was writing.  I think it gives me some insight into the way Carl related to kids.  He always treated them like they could understand and appreciate complex, sophisticated ideas.  Which felt great when you were a teenager who knew him.  When I was the age he was when he wrote this, he would send me manuscripts and ask my opinion of them. I wonder if I reminded him of himself as a teenager, because I can relate to this so much?

But, of course, it’s the brilliant Carl Sagan version of an obsessively nerdy teenager so its full of his particular brand of earnest passionate logical imagination.  Its easy to forget this was the notebook of a 16 year old.  I mean, what a mind!  Pages full of relativistic calculus, detailed capsule summaries of the work of dozens of moral philosophers, calculations of population genetics, musings about cosmology, politics, history, imaginative ideas for science fiction stories and a few wacky speculations: “dinosaurs died of constipation!” “maybe the black rock of mecca is a spaceship?”  “maybe UFOs are really travelling through time from earth in the future?  But why would they need to investigate us if they’re from the future?  It can only mean there was an atomic war and everything was forgotten!”  And designs for spaceships and time machines including one that sounds a lot like the interstellar transport in Contact!  And pages and pages about God!  Elaborate discussions of God’s possible qualities and inherent contradictions and how this or that consideration may or may not disprove the existence of God.  And then there will be something that reminds you that he was still a kid here. The infantile puns and spoonerisms, “American Lay of Wife”  I mean these are, after all, the musings of a 16 year old boy, albeit a remarkable one.  I can remember him scoldingly telling me MY humor was infantile!

He’ll start overanalyzing the behavior of some girl he’s obviously hung up on with some silly nerdy theory.  He was obviously still trying to figure out the whole relationship thing.

But it’s all so Carl.  Analyzing and intellectualizing everything. The energetic, restless mind, searching for connections between everything, throwing out of all kinds of ideas, some of which were half-baked but so many of which are ingenious. 

How can I pick one page? I do kind of like the page that just has the word “Mithraism” on the top and is otherwise blank! 

But OK, I choose page 54. 

A Darkling Plain. Carl Sagan's University of Chicago undergraduate notebook, pg. 54. From The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive.
A Darkling Plain. Carl Sagan’s University of Chicago undergraduate notebook, pg. 54. From The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive.

It reads:

A Darkling Plain 

 (Transcription by David Grinspoon)

Since, as my honors paper shows, all life is structured only for gene multiplication and survival, it should be possible to construct a weltanschaung upon this. We are bucket-passers bound to past +  future, and related to all living creatures genetically. Morality: reproduce so offspring survive.

Predetermination: limits set by genes, free will within these bounds.  War, medicine, science.  Rationality the pinnacle of humanity; not to deny importance of instinctual emotion. 

Woman. Mankind. Possible radiation resistant mutation by cysteine growth in polypetides ? cf bacteria penicillin. Necessary because of >>mutagenesis + carcinogenesis.  Yet it is disturbing to find joy, love, light, certitude, peace, and help from pain relegated to the pragmatic.  Aesthetics, cf. Frued. Cf. Spencer, Bergson, Mill + the utilitarians, (then, a word I can’t decipher).

Does there not exist another element though?  What is the world? What is this “I”?  The desire for liberty, can it be wholly because selected for?  Is there not a spiritual?

 I do not know –-  yet!

(this last paragraph scrawled in an increasingly excited and less disciplined script than the rest of the entire notebook!)

–          Man originally existed in fertile areas.

Various pressures, biological, social, economic, political, even religious, forced him to extend his dominion. In extension, survival became more difficult.  Necessity the mother of invention, hence progress.

-envelope, enveloped.

Reading these notes stretches your mind in several directions at once, makes you laugh and gives you a lot to think about.  So the feeling of reading them is actually not that different from the feeling you might have had after a night hanging out and partying with Carl.

 It makes me miss him.

Comments (3)

  1. What a cool story. Love the original documents. Thanks LOC, Jennifer, Trevor, David and of course Carl for making this great read possible!

  2. Good day,

    First of all, I have to say that I am so jealous. I would have loved to meet him. I once sent a letter to Dr. Sagan regarding the Viking landers after reading Cosmos. I got a reply from his secretary telling me Dr. Sagan was really busy but that if I was fascinated by Cosmos, I should join the Planetary Society. Which I did. I remember watching Cosmos and being overwhelmed by the excitement of learning so much in such a beautiful way. I am now 56 years old and can still return to that feeling when I think of Cosmos the tv show and the book. The excitement continuing through Broca’s brain, The Dragons of Eden and all.

  3. What a great discussion!

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