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View Full Version : Surface age of solar system bodies



m1omg
2015-Oct-25, 05:21 PM
Hello. Is there any table of surface ages for the major rocky/icy bodies in the solar system?

WayneFrancis
2015-Oct-26, 05:05 AM
What do you mean?
The surface age of the Earth varies by location.

Noclevername
2015-Oct-26, 08:05 AM
IIRC only a few bodies resurface themselves; Earth, Europa, Io, etc. The majority of moons and dwarf planets' surfaces have not changed much aside from impacts since they cooled to solid.

John Mendenhall
2015-Oct-26, 08:47 PM
IIRC only a few bodies resurface themselves; Earth, Europa, Io, etc. The majority of moons and dwarf planets' surfaces have not changed much aside from impacts since they cooled to solid.

Agreed aout known resurfacers. The Moon and probaly Merdury are old surfaces. Until we can get to them with explorers, human or automated, I'd reserve judugment. We've seen comets and, IIRC, some moons that look like Swiss cheese.

The OP's idea of assembling a table sounds good. Oh, and what about the gas giants without surfaces?

m1omg
2015-Oct-27, 12:00 AM
Until we can get to them with explorers, human or automated, I'd reserve judugment. We've seen comets and, IIRC, some moons that look like Swiss cheese.

Not just that. Pluto experiences no tidal effect, the orbit with Charon is almost perfectly circular yet it is geologically active and the surface is quite young. IIRC crystaline water ice signatures were detected on some other big KBOs, which means they had to experience high temperature resurfacing. We haven't seen the surface of most dwarf planets and Pluto has surprised everyone by how young and variant the surface is, so I wouldn't claim anything about dwarf planets that we only see as red dots even in best telescopes.

Apart from Callisto, Oberon, Rhea, Tethys, Mimas and Umbriel I don't know of any major moon that hasn't undergone at least some resurfacing. Even the near side of our Moon is quite younger than the far one. So a table showing surface ages for various parts of major solar system bodies would be good.