NASA did a study how to investigate the surface of Europa. It is separate from the Europa Multiple-Flyby Mission, which has a small lander as well, but only with a small budget. Confusingly, the same artist's impressions are used for both. There is also ESA's Jupiter Icy Moons Explorer, launching 2022. The mission would deliver a small lander on Jupiter's moon Europa. The moon has a thick ice crust above a deep ocean, where life could exist. While there are ideas of probes melting through the ice, this mission would just study the surface: During the 20 days of nominal mission time, five ice samples would be extracted and searched for cell-like structures, organic molecules, and substances outside chemical equilibrium. The mission lifetime is determined by radiation damage - it is quite possible that the probe survives longer and can take more samples. Evidence for life could be found if (a) there is life and (b) some cells or chemical products of life reach the surface. While that would certainly be the most exciting possible discovery: Even without traces of life we could learn a lot about the surface chemistry of this exotic world.