The discovery of organic compounds on two of Jupiter’s moons increases the possibility that all of the elements for life are present on another of the planet’s moons, Europa, scientists say.
The finding, from instruments on the Galileo spacecraft orbiting Jupiter, suggests that Europa may have all three of the ingredients scientists consider essential for life: an energy source, liquid water and organic molecules, said planetary scientist Thomas B. McCord of the University of Hawaii.
“This doesn’t mean there is life on Europa,” said McCord, lead author of a study to be published today in the journal Science. “The exciting thing now is the evidence that Europa may have all three of the ingredients.”
Europa is already known to have water and internal heat sources.
Dale Cruikshank, a research scientist at NASA’s Ames Research Center, said the work of McCord and his team should sharpen the research concentration on Europa, which already “is the subject of very special interest.”
“This finding increases the plausibility for life on Europa,” Cruikshank said. “It also supports the idea that there were organic molecules streaming throughout the solar system.”
The study of Jupiter’s moons is part of a growing effort by astronomers and planetary experts to find evidence of life within the solar system.
Instruments on Galileo detected the complex organic molecules on the surfaces of the moons Callisto and Ganymede, suggesting that such molecules are also present on Jupiter’s other two large moons, Europa and Io.
Life on Callisto, Io and Ganymede is considered unlikely because they are dry.
No organic chemicals have been detected on Europa, but researchers have speculated that there may be a rich organic soup below the moon’s ice cap and that this could be a warm, liquid place for the evolution of life.
None of the research so far has proved that life exists or has ever existed on any of Jupiter’s moons, McCord emphasized.