What’s New in Astrobiology

Progress on many fronts, and one very exciting future mission

The Giant Pacific Octopus relies on its tentacles for cognition. Might an alien do the same?

Nearly 1,000 astrobiologists met in Seattle last week to present their latest research results and discuss the most pressing questions facing their field. The meeting, known as AbSciCon, takes place every two years and is the largest such gathering of astrobiologists.

This year the emphasis was on life detection, ocean worlds, and exoplanets. In the latter area, the neighboring Alpha Centauri system received particular attention. It appears we are on the verge of finally being able to acquire information on a nearby exoplanet’s habitability rather than just its physical characteristics such as mass and radius, and this has led to much anticipation in the community.

The greatest excitement at the meeting, however, was over the announcement that NASA has selected a new mission called Dragonfly to send a drone to Saturn’s moon Titan—a wonderfully exotic world with hydrocarbon lakes and an atmosphere roughly resembling that of early Earth. Titan has lots of organic chemistry going on, and this mission could reveal whether these complex molecules may have assembled to become primitive life.

Other talks at the meeting showed just how much progress is being made across the various disciplines of astrobiology. Jody Deming from the University of Washington discussed how the presence of viruses in concentrated seawater brines, surprisingly, enhances the survival of bacteria. Dominic Sivitilli, also from the University of Washington, gave an inspiring talk about “soft body” intelligence and explained how an octopus with most of its cognition executed in its tentacles rather than in its brain interacts with its environment. It was a great demonstration of how different the anatomy and cognition of intelligent life can be—an obvious lesson for thinking about life on other planets.

Barbara Sherwood Lollar from the University of Toronto, Canada, talked about the observed methane spikes on Mars—one of many talks on this subject. She went a step further, however, and suggested how molecular ratios of released gases—particularly the ratios of methane to hydrogen and methane to ethane—could be used to distinguish between a biological source and a chemical source.

Kai Finster from Aarhus University in Denmark discussed how wind-abraded silicates and direct exposure to wind-driven saltation on Mars quickly kills microbes, and even their spores—in effect sterilizing the planet’s surface. This could ease many planetary protection concerns for future Mars missions. The process also seems to solve the puzzle of how methane is quickly removed from the Martian atmosphere and to explain why observed methane releases such as the one recorded by the Curiosity rover about a week ago do not last long.

Results like these were exciting and encouraging to the meeting participants. The only downer was NASA’s decision to select no new Astrobiology Institutes. The current system is supposed to be replaced by so-called “research coordination networks,” and many researchers fear losing the funding that allows them to continue their work. We can only hope this won’t be the case, and that there will be plenty of new results to report at the next Astrobiology Science Meeting, planned to be held in Atlanta in 2021.