2 ms·
Well, it's more viable than you might think. Putting a 300 degree sphere on the surface would eventually get somewhere. But getting anything useful back is pret
by jvanderbot 2y ago
Well, it's more viable than you might think. Putting a 300 degree sphere on the surface would eventually get somewhere. But getting anything useful back is pretty hard, since you'd have a probe that's boiling water below 25km of ice and probably far from the lat/lon it landed at.
- perihelions 2y agoYou could make it buoyancy-neutral and have it float-melt its way back—heater pointed up.
- ethbr1 2y agoI'd never considered the pressure under an ice cap... it would scale with depth, no? So a water channel within the ice (going "up" from the sea below) would have a decreasing pressure gradient as it ascended?
- mattlondon 2y agoI would imagine the water channel would re-freeze fairly rapidly, so you'd end up with a "bubble" of liquid water around the thing slowly melting itself down.
- ethbr1 2y agoPoint. Is ice sufficiently plastic to exert pressure with depth? I honestly don't know. E.g. What would the pressure of a bubble of water under 1km of ice vs 15km of ice?
- nick238 2y agoThe ice clearly moves, as Europa's surface isn't just same as an airless, solid ball-of-rock's default: craters, but has all sorts of features that reshape the surface, so given enough time, it'll equilibrate. (What 'enough' means is left as an exercise to the reader). There are papers[1] that discuss the ice properties, but it's hard to get a specific answer out of them. There have to be tons of research papers out there about the design criteria for melt-drill probes like this, for Europa, Enceladus, and others. [1]: https://websites.pmc.ucsc.edu/~fnimmo/website/draft5.pdf https://websites.pmc.ucsc.edu/~fnimmo/website/draft5.pdf
- BitwiseFool 2y agoMaybe the main melt probe could leave behind little RTG powered relays as it descends. They'd get frozen in place as the main probe continues melting its way down.