Astrobiologists In Search of a Breakthrough
Researchers consider the frontiers of life at an annual conference in Berkeley.
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At last week’s “Breakthrough Discuss” meeting in Berkeley, California, the focus was on the migration of life in the Universe and the search for extraterrestrial life and genomes. The annual conference, sponsored by the Breakthrough Initiatives organization, came only a day after the first pictures from a black hole were published, and the same day Israel’s Beresheet probe crashed on the Moon—a reminder that grandeur and failure sometimes go hand-in-hand when advancing high-risk space projects.
The meeting opened on an inspirational note, with music from Star Wars and a video message from the late Stephen Hawking. During the first session on the migration of life, the question loomed large whether panspermia, including the transport of life to Earth from outside the solar system, is possible. Most scientists in the panel discussion seemed to agree it was likely within the solar system, as has been proposed for Venus, Earth, and Mars. They were less enthusiastic about the spread of life from interstellar space, although Steinn Sigurdsson of Pennsylvania State University theorized that an object as extremely “fluffy” as Oumuamua could still deliver a load of microbial life to a planet with a significant atmosphere (such as Earth), because the microbes would slowly and relatively gently descend to the planet’s surface. He reasoned that encounters with interstellar objects may have happened 100 times in Earth’s history.
For me, the highlight of the second session was a talk by Steven Benner from the Foundation for Applied Molecular Evolution, who reviewed experiments showing that DNA-like chemicals with six or eight bases—instead of the four that DNA has—can also function and transmit information. This underlines again the likelihood that if we find life elsewhere in the Universe, it probably has some other nucleotide-based information code besides DNA. Benner went on to present a new, far-reaching hypothesis claiming that the first life form on Earth probably originated as an RNA-based cell about 4.36 billion years ago, because only at that time did Earth’s atmosphere have the right chemistry for life to originate.
In the same session Drew Endy from Stanford University talked about the intriguing idea of searching terrestrial DNA for possible extraterrestrial messages. While the few attempts to do this have proven fruitless, these kinds of investigations result in a better understanding of how our genetic code is constructed. In another talk, Marileen Dogterom from the University of Delft in The Netherlands suggested using synthetic cells for space applications, for example to make materials needed for human space missions. But she made clear that the artificial engineering of cells still has a long way to go before this kind of thing could happen.
The meeting wrapped up with a discussion of life emigrating from Earth, including talks by Aaron Engelhart from the University of Minnesota on how to survive on Mars once we get there, and by Robert Zubrin, president of the Mars Society, on how the information storage capability of microbes could be used for interstellar communications.
Overall, the conference featured quite a few interesting and even “edgy” talks about the frontiers of research in astrobiology. In my view, the field—with the exception of exoplanet research—has advanced way too incrementally in recent years. I believe one promising way to achieve more rapid progress is the one taken by Breakthrough Initiatives—getting the best scientists in the field together to question paradigms and come up with new ideas and hypotheses.
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