Very little is known about Jupiter's moon Europa other than flybys from the Voyager 2 and Galileo spacecraft, but NASA scientists may now have a reason to give it a closer look.

According to a NASA Jet Propulsion Laboratory (JPL) news release, those quick flybys from the late 70s and 90s showed images of a rough icy surface that may be able to sustain life. Scientists believe there could be a water ocean beneath the surface, but they would not know unless they landed on it.

A new study, published in Astrobiology and conducted by a NASA-appointed science definition team, mapped out a series of questions to be answered about the mysterious moon.

"If one day humans send a robotic lander to the surface of Europa, we need to know what to look for and what tools it should carry," said Robert Pappalardo, the study's lead author, based at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "There is still a lot of preparation that is needed before we could land on Europa, but studies like these will help us focus on the technologies required to get us there, and on the data needed to help us scout out possible landing locations. Europa is the most likely place in our solar system beyond Earth to have life today, and a landed mission would be the best way to search for signs of life." 

The team's main questions centered on the moon's composition and what the reddish "freckles" and cracks in the surface were. A number of scientists from other universities and NASA affiliates co-authored the study, including Johns Hopkins University Applied Physics Laboratory, Laurel, Md.; University of Colorado, Boulder; University of Texas, Austin; and the NASA Goddard Space Flight Center, Greenbelt, Md.

Other issues they found needing to be addressed were how the gravitational pull of Jupiter would affect people on Europa's surface. Currently, there are many unanswered questions that could only be answered by landing on the surface.

"Landing on the surface of Europa would be a key step in the astrobiological investigation of that world," said Chris McKay, a senior editor of the journal Astrobiology, who is based at NASA Ames Research Center, Moffett Field, Calif. "This paper outlines the science that could be done on such a lander. The hope would be that surface materials, possibly near the linear crack features, include biomarkers carried up from the ocean."