Icy Moons Are Ocean Worlds
mceglowski.substack.com125 points by worldvoyageur a day ago
125 points by worldvoyageur a day ago
Set your calendars:
Europa Clipper, launched 2024, starts Europa flybys on March 2031
Dragonfly, hopefully launching July 2028, arriving on Titan 2034
> This remarkable transformation in our understanding is the result of just three missions: Voyager, Galileo, and Cassini—along with some computer modeling and hard staring by the Hubble and Webb space telescopes.
Seems odd to neglect to mention New Horizons immediately after mentioning the probable existence of liquid oceans under Pluto's surface, a finding made possible thanks primarily to New Horizons.
No shade on New Horizons intended, but I was talking about the early 2000's revolution in understanding of ice moons/ocean worlds, and that preceded the Pluto flyby by a lot.
It was a valuable piece of corroborating evidence, but not shocking and unexpected in the way results from those three missions were. We had good reason to believe Pluto would look a lot like Triton, and it does.
Great read, other than Europa I wasn't aware of these other candidate ocean moons.
TIL
> The radiation environment around Europa is punishing; an astronaut standing on the surface would get a fatal dose in about a day
Beautifully designed article. Very cool images and diagrams.
> We want rocks in contact with water,
But there is ice compressed between the water column and the xenoceanic bottom, ok. I see the problem.
What about rocks in the surface of the water?. Some volcanic rocks can float.
> What about rocks in the surface of the water?. Some volcanic rocks can float.
This is... not something you lay plans on. Even on Earth, these rocks are formed at surface pressure, just barely float, and don't float for long (I've tried). If they form in the deep ocean, I'm guessing the pressure isn't going to let the bubbles be big enough to create bouyancy at all. Either way they would be super rare.
I guess I'm now officially old and cranky, as planetoids receiving glow-ups was just a bit much as a term.