Europa, one of the many moons of Jupiter, has become a topic of great interest among experts, scientists and NASA.

Even Bill Nye of the US Planetary Society is among those who are quite interesting in exploring Europa. NASA is equally excited and is setting aside $25 million for designing scientific instruments to know about the habitability of Europa.

The agency has invited proposals from scientists for experiments for a Europa probe that could be launched in 2020s. Out of these proposals, around 20 will be chosen to receive share of the money for further study.

On Tuesday, John Grunsfeld, associate administrator for NASA's Science Mission Directorate, said around eight instruments will be selected. They could provide answers to the fundamental questions about Europa. Spacecraft instruments will be used to conduct scientific investigations with regard to science goals for Europa's explorations outlined in the National Resource Council's (NRC) Planetary Decadal Survey.

Important objectives include specifying the extent of the ocean and its relation to deeper ocean; details about the ice shell and if any sub-surface water and nature of surface-ice-ocean exchange and understanding Europa's space environment.

"Proposals must be responsive to one or more of the six objectives", affirmed Curt Niebur, Outer Planets Program scientist at NASA Headquarters in Washington.

Grunsfeld further affirmed that it is the possibility of life on Europa that is acting as motivating force for scientists and engineers.

As per the data gathered by NASA's Galileo spacecraft, Europa's image shows the blue-white terrains. It indicates pure white ice. Researchers are very much interested to know these features as they may offer a way by which they can assess the habitability of the moon's interior ocean.