eum and Chicago's famous Soldiers Field where Jerry Garcia played his last show in 1995. It was all so near, yet so far away. We were like museum specimens encased in glass, subjects of a 3-day experiment in science communication.
Astrobiology is now a decade-long experiment in overcoming disciplinary boundaries, forging collaboration between scientists. This workshop seemed like an attempt to push the experiment one step further. Can we go beyond the traditional boundaries and include journalists, educators and social scientists in the process of science? Or should they remain on the sidelines, watching and reporting on our scientific activities? Including others does lead to better communication, but it also requires patience, since it takes time to explain everything to the uninitiated.
Inevitably in a program this experimental, there were a few problems. To stay on schedule, after each science talk we were only allowed to ask "questions of clarification". Then, at the end of the session, we would supposedly get a chance to ask more substantive questions about the science during a panel discussion with the respondents. However, the panel discussions often went in different directions due to the respondent's opening talk. Thus we couldn't always ask the questions we wanted to ask, and we lost some of the give-and-take of a normal science workshop. This was frustrating, as many of the talks stimulated questions I wanted to ask, and I wasn't the only one who felt this way.
For example, Sara Seager from the Carnegie Institution gave an excellent talk about "vegetation's red edge". Green plants (trees, plankton, and other species that use chlorophyll to capture the energy of sunlight to manufacture food) are brightly reflective in the near-infrared. Seager's attempt to find out why struck me as a great example of astrobiology in action. Astrophysicists interested in the spectral signature of an inhabited Earth-like planet have become aware of this spectral feature of green plants, but biologists have never tried to explain it. Now, thanks to astrobiology, astrophysicists are helping biologists try to understand this puzzling global property of life on Earth.
Image Credit: The University of Liverpool
Seager suggested the red edge of green plants may be a result of the need for thermal regulation. Because green plants absorb a lot of sunlight, they could overheat. But being reflective in the near-infrared might help them to shed excess heat. This is truly a cool idea. At the end of her talk I wanted to ask this: "Your idea suggests that photosynthetic life adapted to very cold places may NOT show the red edge. A way to test this would be to look at organisms adapted to cold places, like photosynthetic extremophiles in Antarctica. Has anyone looked to see if they show the red edge?" If this thermal-regulation hypothesis is correct, then habitable planets on the outer edge of the habitable zone, farther from a star, might not show the red edge effect.
During the meeting there was much discussion of the recent NASA budget cuts to astrobiology, and what this might mean for the future of the field. Even though many are experiencing harder times, and students are facing uncertain employment prospects, the field of astrobiology doesn't seem to be shrinking or retrenching. Even though the funding situation has people nervous, that didn't dim the enthusiasm about future projects like the Terrestrial Planet Finder. The overall scientific theme of the workshop was finding habitable Earthlike planets around other stars, so there was much talk about observations to be made with TPF and other instruments. Nobody doubts that we will build instruments to study rocky planets in our galactic neighborhood. The "we" in this case could mean the current generation of astrobiologists, or our intellectual descendants.
At any rate, somewhere, somebody in the galaxy is looking through a telescope, searching for planetary dots of any color. Maybe our pale blue orb will enter their field of view. They would be able to monitor the gas composition of our