Top Story: August 17, 2010

ET – What and How?

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We’re continuing our coverage of SETIcon today discussing ET or extraterrestrial life. What would this life look like? How would it survive? Where would you look for it?

To begin, scientists are thinking basic when looking for life.  When we think of ET or aliens, we tend to imagine an intelligent creature, not a microbe.  However, as Seth Shostak remarked toward the end of the conference, in this particular search (for extraterrestrial intelligence), not only does life have to exist in a basic form, but it has to exist in a technological state in order for us to communicate with it. But you gotta start somewhere.

And many astrobiologists have started right here on Earth, looking in weird places.  to determine what form ET might take.  One session at SETIcon was called “It’s a Dirty Job: Searching for Life in Extreme Places.” Scientists spoke about extreme life on our planet, from bacterial life at the bottom of Antarctic lakes to the Atacama Desert, and how what we find here might translate to other planets.... or moons.

A question was asked about Saturn’s moon Titan— could life possibly exist there? A quick answer was, not life as we know it. Methane probably could not sustain life.

So this begs the question which an audience member actually asked  - what is needed for life to exist? Previous Dean Lecturer Margaret Race said scientists think it’s these three things:

  1. Liquid water
  2. Chemical compounds
  3. An energy source

But she went on to say that “we’re not sure where the edges are for life as we know it.”  This is illustrated in the fact that there are microbes that live in the cooling water of nuclear power plants and in the Atacama Desert where there is lots of radiation. Radiation disrupts the bonds of proteins (number two on our list above). Have these microbes evolved to repair that?

Race mentioned that, in order to figure out this question of extraterrestrial life, some astrobiologists are getting into the realm of synthetic biology.  In particular, they want to determine how life starts here or elsewhere.  Interesting – creating elements of life to make sense of it.

Scientists will continue to address these and other questions about extraterrestrial life; and we’ll wait to see what they find out.  In the meanwhile, stay tuned for the Academy’s next planetarium show, Life: A Cosmic Story. Opening November 6th, the film will take audiences through Earth’s history and describe the geological evidence for the origin of life.

Image courtesy of NASA

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