Water plumes over Europa Options

[marsbug]

This seems like the relevant place to post this (could be wrong): Water plumes from Europa? Apologies if it's already been up. The link to the Science article at the bottom doesn't work for me, does anyone have a working link to the original? Cheers.

[Julius]

I still cannot come to terms with the idea that Europa has moved from tectonics (ridge formation) onto chaos as the ice crust has thickened over its 4 billion year history. I guess radar should tell us a lot about what is actually happening.

[JRehling]

From Nimmo and Manga (2009):

"The manner in which Europa’s shell and interior evolved to their present-day states represents a major unsolved problem for at least three reasons. First, the present-day state, especially of the silicate interior, is poorly known. Second, Europa’s surface may only record the last 1% of its existence, so there are few constraints on its earlier history. Third, the thermal and orbital evolution of Europa are intimately coupled in a manner that is nontrivial to model."

https://websites.pmc.ucsc.edu/~fnimmo/website/draft5.pdf

One significant work since then was the melt-lens model of Schmidt, et al (2011):

https://www.nature.com/articles/nature10608?proof=trueNov

In a nut [ice] shell, the internal dynamics and certainly the history of Europa's ice shell are far from determined, although the tidal forces that create the most visible linea have probably been modeled well.

Even after one or several more missions, I doubt if we will have good information about the history of Europa's ice shell pre-dating that "last 1%" but finding out what's going on there now is something I'm very much looking forward to.

[StargazeInWonder]

This is just a teaser for now, but JWST will attempt to detect and characterize any Europa plumes, which were detected, but at low signal, by HST, and were detectible only sometimes. JWST has the capability to detect spectral features that HST is simply not capable of, those above 2.5 microns. That corresponds to CO2, among other possible components. Of course, what it actually detects will depend on what, if anything, is actually there when it observes.