Some thoughts inspired by
The Shores of the Cosmic Ocean, by Carl Sagan
By Jeffrey Van Cleve
Dr. Jeffrey Van Cleve is an astronomer and support scientist on the Kepler Team. His area of special expertise on Kepler, as on his previous flight programs, is focal planes. He enjoys learning a little bit about a lot of things and explaining them to others, so he has worked on documentation like the Instrument Handbook and the Data Release Notes for the last year. In his spare time, Jeffrey enjoys hiking and taking advantage of all the wonderful things the Bay Area has to offer.
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As I watched Carl Sagan travel in his “Ship of the Imagination” in “The Shores of the Cosmic Ocean,” I felt amazement at the achievements of the human mind and hand, not only in Sagan’s message but also in the medium through which I was viewing it: the iPhone, YouTube, and all the technology behind them; we’re some pretty smart monkeys, after all. As Sagan’s journey started with a dandelion, went to the edge of the Universe, and returned, I felt a sense of beauty, like Blake, “to see a world in a grain of sand, and a heaven in a wild flower.” I felt a sense of loss, in that the Future of the early 21st century did not bring crewed interplanetary travel, artificial intelligence, and fusion power as we imagined it would in 1969; I will be fortunate to see human beings leave low Earth orbit for the Moon or an asteroid before I retire sometime between 2025 and 2030, and I may not live to see humans land on Mars. I felt loneliness, as he crossed great gulfs of space and (implicitly) of time on an empty bridge, without a human companion, a pet, or even a potted plant. I felt dread and unease, as Sagan’s Ship passed the lights of an alien civilization and he wondered, “Are they also a danger to themselves?” which reminded me of my own unconvincing and disturbing wrestling with the Fermi Paradox. Finally, I felt the courage behind the idea that we can understand the Universe, and share that understanding through science, when the ruling powers throughout most of history have proclaimed that the Universe is beyond our rational comprehension.
We see the large in the small, and vice versa, in the Blakean perspective of Sagan’s journey. Likewise, the half hour or so I spent re-watching it encompasses a whole lifetime of my thinking about space exploration and alien intelligences. For me, the exploration of space and the search for other intelligent species are the foundations of an optimistic and expansive vision of the human future, a great stage on which the human comedy and drama can be played in ever-increasing circles. As a child, I watched that drama play out in the Space Race, and was fortunate that the high-water mark of human space exploration between 1965 and 1972 occurred in my most formative years. In my early teens, I watched that drama play out in fiction, in Dune, Foundation, and Star Trek, and became interested in rocketry and astronomy not so much to learn about the Universe for its own sake, but to be part of the same narrative as Paul Muad’dib and James T. Kirk, if only as a forgotten ancestor. I studied physics, in the belief that under the foundations of physics was the key to open the door to the stars: antimatter rockets, wormholes, time machines, or antigravity. Soon after graduating college, I left fundamental physics and these dreams slept for reasons I still do not fathom. One day in 1987 in the bus station at Port Authority in New York City, while waiting for a bus to Ithaca, I read Whitley Strieber’s Communion, which made the hair on my arms stand up, and made me wonder why I was in grad school studying solid-state physics when the stars in all their terror and majesty awaited. I changed career paths as soon as I could, and by 1990 I was working on my first space program, the Spitzer Space Telescope.
I currently work on Kepler, which watches stars to see if they dim, periodically, when a planet about the size of the Earth passes in front of its star. The planets we are most interested in orbit their parent stars at the right distance for them to hold liquid water, which we believe is essential for life. Kepler addresses one part of the great question, “Are we alone?” which was broken down over 40 years ago into subsidiary questions by Frank Drake – a remarkable parsing of our ignorance which has been cited countless times. So rather than be overwhelmed by the scope of the great question, we can with some confidence address one of the subsidiary questions, which in the case of Kepler is “What fraction of stars have planets like the Earth?” It is like building a pyramid or a cathedral, in which we can find satisfaction even though both the origin and the completion of the work lie beyond our lifetimes. In the case of Kepler, we can look back to Lucretius, Giordano Bruno, and Kepler himself; we can end-run the great question now by listening for signals from extraterrestrial intelligence; and we can look to the future to missions that can measure the spectra of extrasolar planets to detect the exhalations of life.
The Future, though, is not what it used to be; the prospect of interplanetary and interstellar travel, and ultimately civilization, remains uncertain. 2001 did not look at all like the movie, as far as the human exploration of space is concerned, and it is hard to say whether 2001 will come to pass by 2100, if ever. Conversely, we have no evidence that someone else is exploring space; much as Communion inspired me, I cannot in good scientific conscience say that the evidence supports the view that extraterrestrials are visiting us now, and the Great Silence of SETI continues. I remain hopeful though, that the projects – like Kepler – that do happen, even in this complicated and fallen world, are signs that the human spirit is still pressing towards that future. Even if we do not live to see the first starships, we can at least find their first destinations, and search for companions on the far side of that sable sea.