Astronomers have long been keen on finding out whether or not there is life outside Earth. One of the alien worlds experts are interested in is Europa, one of Jupiter's moons.

Although Europa is only about a quarter of the size of Earth, it has about twice as much liquid salt water compared with what is in our planet and the vast oceans lying beneath its outer shell is the very reason why scientists think that if life indeed exists in the solar system other than on Earth, this would likely be found in the waters of Europa.

Now, scientists are closer to finding out whether or not there is life on this icy world.  The 2016 federal budget allocation for NASA includes allocation for a mission to Europa and this may involve hunting for signs of alien life in the ocean-harboring world.

The current mission concept known as the Europa Clipper involves sending a spacecraft to orbit Jupiter and make several flybys of Europa over a period of three and a half years. The $2.1-billion mission would take a closer look at and capture photos of the moon to provide researchers with better understanding of the characteristics of the water including its depth and salinity.

The spacecraft would also map and measure the icy shell, which could be crucial for future missions on the moon's surface.  

Scientists, however, have to figure out first how to actually detect life on Europa, a challenge that led to a special workshop held at NASA's Ames Research Center on Wednesday that had planetary scientists and astrobiologists discuss ways for finding life on the moon.

"Europa is clearly such a prime target for astrobiology that having a workshop like this to try and figure out all the ways in which we could possibly sample its ocean ... [is] critically important," said astrobiogist Kevin Hand, from California's Jet Propulsion Laboratory.

Although the mission has long been under review, scientists now ponder on modifying it to also include instruments that are capable of finding signs of life.

NASA has already asked scientists to consider ways to find evidence of life in the plumes of water vapor that appeared to have blasted from the moon's south polar region.   Researchers said that the plumes could provide a way to sample the Europa's potentially life-harboring waters.