Jupiter's moon Europa is an interesting place. It has more water underneath its surface than Earth, while being much smaller than Earth [1]. Moreover, its underwater oceans are ten times deeper than the oceans on Earth.
Wherever there is water, there is chance of life, even if it is a microbial one. This is why NASA is interested in going there to look for possible signs of life [2]. What has motivated NASA even more to explore Europa are the plumes detected by the Hubble Space Telescope. These plumes likely consist of water vapors, and reach more than 100 miles above the surface. Now why these plumes are so interesting? That is because, if they really do exist, they could contain molecules that hint at whether Europa possesses life building blocks.
After getting this information from the Hubble Space Telescope, NASA had a look at the data it obtained from Galileo, which is a Spacecraft that flew over Europa more than 20 years ago. From that data, they noticed that the instruments on Galileo measured increased density of electrons and a swing in the magnetic field while travelling over a region, where the Hubble Space Telescope also detected plumes.
It has to be noted thought that the Hubble Space Telescope sometimes detected those plumes while sometimes not. So, NASA would take that into account when looking for those plumes over Jupiter. But its a very exiting news nevertheless for people like me, who would be exited to even hear about microbial life being present anywhere in the Solar system.
References
[1].https://www.space.com/22207-jupiter-moon-europa-water-ocean-infographic.html
[2].https://mobile.nytimes.com/2018/05/14/science/europa-plumes-water.html?mc=adintl&mcid=keywee&mccr=intmob&ad-keywords=IntlAudDev&kwp_0=812278&kwp_4=2787468&kwp_1=1183455&dclid=CJm1mOvAlNsCFds54Aod-JYAmw