Dead or Alive?

mars earth

Mars has long been everyone’s favorite place to search for extraterrestrial life.  A century ago, Percival Lowell and other astronomers thought that the Red Planet was laced with artificially dug canals, a convincing sign of an advanced, martian society.

Today, we know the canals were optical illusions, but there are still good reasons to think that Mars – which once had vast amounts of liquid water on its surface – may have spawned life.  Many of the astrobiologists at the SETI Institute study the hydrological history of Mars, hoping to learn “where the bodies are” (either dead or alive) of this possible Red Planet biota.

Other SETI Institute researchers are betting on different venues for life in our Solar System.  Three of Jupiter’s moons – Europa, Ganymede, and Callisto – are thought to harbor deep, salty oceans beneath their surfaces.  These unseen waters have been present for billions of years.  Could they have cooked up some microbial inhabitants?

Similarly for at least two moons of Saturn, Enceladus and Titan.  The latter is known to have lakes of liquid hydrocarbons dotting its surface.  Could there be single-celled denizens in these gooey ponds?  Again, SETI Institute scientists are on the case.

Beyond our Solar System, there’s the exciting possibility of intelligent life elsewhere.  SETI Institute scientists have pioneered the search for radio (and optical) signals from other worlds, and are using the Allen Telescope Array to press the hunt for indications that someone is out there with the cognitive capability of humans – or more.