In the 1997 Sci-fi drama “Contact”, actress Jodie Foster eventually manages to establish brief communication with an alien life form from the Vega star system, 26 light years from Earth.

But despite the discovery of thousands of new planets in the ensuing years, there has been little evidence to support the existence of alien life on any of them.   As it turns out, one of the best places to find traces of life beyond Earth could be in our own backyard, astronomically speaking.

The planets and moons of our own solar system contain diverse concoctions of chemical soup that may house alien life in its most primitive form. Scientists at the SETI (Search for Extra Terrestrial Intelligence) Institute recently formulated a list of 6 locations within Earth’s solar system as potential ET hang-outs.

Jupiter's moons Titan (background) and Enceladus

Titan and Enceladus(103464)

1. Enceladus

This tiny Saturn satellite revealed some of its secrets when the 2005 Cassini probe provided stunning photographs of the southern hemisphere.  Frozen water spewed spaceward from beneath the surface through cracks marring the landscape.  Scientists theorize the water is kept relatively warm by the huge gravitational tug-of-war between Saturn and other nearby celestial bodies. The basic alien life building blocks exist in these subterranean incubators and could be verified by obtaining an atmospheric sample from the enormous geysers.

2. Titan

Saturn’s largest moon is the only celestial body in our solar system (other than Earth) known to contain significant evidence of surface liquid.  In addition, Titan has its own atmosphere.  While these elements may seem like an enticing place to settle down, unfortunately the liquid on the surface is mostly ethane and methane, and the atmosphere is a toxic mixture of hydrocarbons combined with a temperature of -290 Fahrenheit.  While this may not be a vacation destination for Homo sapiens, the ongoing chemical processes intrigued scientists enough to send a lander there in 2005.

3. Mars

Yes, Mars.  The Martian life forms popular with Hollywood film makers are not the sort man is likely to encounter there.  This perennially popular choice for alien habitats does have a few interesting features that keep extraterrestrial hunters piqued.  One of these is the dark stripes that appear during the Martian summer at the Horowitz crater.  Many scientists believe water may run beneath these stripes.  This theory could be easily proven or disproven with a technologically simple probe to the Martian surface.   And recently, a study of Martian meteorites showed that water was a major player during the planet’s formation and that large amounts of water were stored throughout the interior at some point.

4. Europa

Europa orbits the planet Jupiter and is always on the short list for alien life environments because it has an atmosphere that consists mostly of oxygen. It also contains a vast amount of liquid water.  Unfortunately, these oceans are beneath 10 miles of ice. In addition, the 10-mile shield of ice effectively prohibits any photosynthesis as we know it to take place.  However experiments in Russia’s Lake Vostok have demonstrated the ability of some organisms to thrive in extremely harsh environments. 

5. Venus

Venus, with its proximity to the sun and surface temperatures exceeding 850 degrees Fahrenheit, is not normally a consideration in the search for alien life.  However some scientists theorize that the chemical reactions high in the relatively balmy Venusian atmosphere may be conducive to primitive extraterrestrial life. Studies are currently underway to determine how sulfur dioxide and carbon monoxide react to potentially  become part of a food chain for airborne microbes.

6. Ganymede and Callisto

Both moons of Jupiter  are listed as potential candidates for alien life but any efforts to verify it will likely take place in the distant future.  Like Europa, both these moons have underground oceans.  However unlike their more famous sister, the oceans on these two moons are buried beneath 60 miles of solid rock.  So while these oceans may indeed be teeming with alien microorganisms, there is no technology in place now or in the foreseeable future for humans to put a lander on these moons, bore 60 miles down, and take samples to be analyzed.

Discovering life beneath the buried seas of Europa, Callisto and Ganymede will be the task of future generations.  Exploring the surfaces and atmospheres of Enceladus, Titan, Mars and Venus is within the scope of human capability now. Many of us may live to see the exciting day when life is discovered outside the boundaries of planet Earth. The article Leave the Aliens Alone is an interesting perspective on what may happen when Contact leaves Hollywood and becomes reality.