March 30, 2012

Cassini Searches For Potential Life On Saturn’s Moons

The Cassini spacecraft has captured new images and measurements of some of Saturn´s moons. This new evidence may help scientists determine if life does exist outside of Earth´s closed system.

Enceladus, the moon with the most promise for microbial life, has cryovolcanic geysers on its surface that spews into the moons thin atmosphere. The Cassini spacecraft flew into these plumes at an altitude of 46 miles above the surface. They used the ion and neutral mass spectrometer instruments to sample the composition of the moons south polar plume.

The geysers were found to contain organic compounds. These organic compounds contain carbon in their composition. Scientists consider these compounds to be the foundation of life because life on our own planet is carbon based.

Now that the scientists know where to look for potential signs of life, it will be relatively easy to access these lifeforms. But for now they will continue “tasting” the plumes for signs of life.

Dr. Carolyn Porco, head of the Cassini imaging team, “Cassini has flown several times now through this spray and has tasted it. And we have found that aside from water and organic material, there is salt in the icy particles. The salinity is the same as that of Earth´s oceans.”

The spacecraft also made a nine-image mosaic of the moon´s surface as it flew by.

Cassini flew other missions while it was in the neighborhood. The spacecraft flew by Janus, flying by at a distance of 27, 324 miles, with Saturn in the background.

The spacecraft then passed another moon, Dione, at about the same distance and recorded observations, including a nine-frame mosaic showing the side of the moon that faces away from Saturn.

Scientists speculate that Dione may also exhibit geologic activity similar to Earth and Enceladus. This activity, though, is as energetic as that of Enceladus.


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