The Key To Finding Extraterrestrial Life is Right Here at Home
The search for extraterrestrial life begins on the planet we call home, at least that is according to speakers at the 2015 NASA Astrobiology conference. Three speakers for different scientific disciplines presented different ways that scientists are joining the search for alien life without ever leaving Earth - by studying phenomena ranging from extreme life forms to sunlight on the ocean and the properties of Antarctica.
Professor of Geological Sciences at UCB and principal investigator of NASA's"Rock-powered Life" team, Alexis Templeton is interested in studying the capability of rocks to store energy that can be used to power biological systems.
"Essentially, there's a fundamental understanding that rocks have within them, depending on their chemistry, the ability to release electrons or components that can fuel and power different systems essentially much like fuel cells do,"Templeton explains. And one of the big questions at the moment is how we can couple the energy that's stored within rocks into biological systems," Most notably, rock energy could mean that organisms wouldn't need the sunlight to survive, but could instead thrive in subsurface environments. If rocks can serve as an energy source for biological organisms, then the terrain on which life can thrive would be opened up to new possibilities.
Currently, this potential is being investigated in life-forms found in the desserts of Oman, where rocks formed deep in the Earth's mantle have come to the surface in natural pools, changing the chemistry of the water they come in contact with. Life-forms discovered in these pools are not only surviving these harsh conditions, they've evolved to flourish in them. Templeton and her team put forward the notion that perhaps biological life forms on other planets have adapted in similar ways.
The search for alien life is also being aided by research taking place in the ocean below the Antarctic ice. Britney Schmidt, assistant professor of Earth and atmospheric sciences is a proponent of the theory that life could be found in sub-surface oceans, such as the ones found on Jupiter's icy moons. Schmidt is the principal investigator of NASA's Sub-Ice Marine and Planetary Analog Ecosystems project, which looks at Earth's oceans in the same way scientist would want to study the oceans of Europa. NASA also recently announced that they were including a suite of instruments to go aboard a planned satellite mission to Europa and test what lies beneath its icy surface.
But perhaps most interesting of the three techniques presented is Professor of Astronomy Vikki Meadows' theory on the glint effect. The glint effect is something that scientists have long theorized might reveal the presence of an ocean on a distanct exoplanet. But until recently, no data had been collected. Meadows presented an image taken by the LCROSS satellite, showing the Earth as a partially illuminated crescent. The depicted curve of silver light featured a slightly brighter section right near it's midpoint - a section Meadow's identified as a glint of sunlight reflecting off the ocean. "We have more confidence now about predicting the type of signals we might be able to detect from extrasolar planets when we go for the gold and actually try to detect an ocean on another planet," says Meadows.
You can watch the full panel from NASA's 2015 Astrobiology Conference in the video below: