Two of the Solar System's most fascinating Moons are showing some of their secrets to space based telescopes and orbiting probes.
Firstly, Jupiter's Moon Europa has been imaged by the Hubble Space Telescope recently and the image indicates that it is actively expelling water vapour.
It has been known for some time that Europa is active - as a result of tidal stressing by Jupiter and the other three Galilean Moons, Io, Ganymede and Callisto.
So this recent news is a significant boost for the hoped-for discovery of liquid water underneath the ice sheet of Europa's surface.
Also it will intensify the work going on to put together the next mission to Jupiters' Moons, beyond JUICE, which is currently on its way.