The Jovian system is a busy place. The Groovy Galilean Satellites session at last week's Lunar and Planetary Science Conference (LPSC) covered analysis of past mission data, testable hypotheses for future missions, and discussion of the use of ground-based data.
It is not easy to observe Jupiter’s moons as more than points of light with Juno, because Juno will never get very close to any of the moons, but as its orbit shifts there will be opportunities to collect data on some of the moons.
We're now just about 12 hours away from Juno's Jupiter orbit insertion. As anticipation ramps up, NASA has released this sneak peek at JunoCam's approach movie, made of views of Jupiter and its largest moons shot during the final approach, up until about five days ago.
A newly published paper confirms a subsurface ocean at Ganymede. An ocean there was already suspected from its magnetic field and predicted by geophysics; new Hubble data confirms it, and even says it is in the same place we thought it was before. Such consistency is rare enough in planetary science to be worth celebration.
I'm absolutely floored when I stop to think that our beautiful blue ocean is only one of perhaps a half dozen or more oceans on other worlds in our solar system, and only one of probably millions (or more) oceans on other Earth-like planets in our galaxy. Oceans abound!
Reports from the March 19 session at the Lunar and Planetary Science Conference covering eight icy moons in the outer solar system: Ganymede, Europa, Dione, Rhea, Mimas, Tethys, Enceladus, and Miranda.
Not many subjects remain for which it is possible to assemble everything that we know about it in one book. Even for those subjects for which our knowledge is limited, knowledge seems always to be expanding exponentially. This is not true, however, for the Galilean satellites of Jupiter.