View Full Version : Debris From Lunar Breakup Question.

2012-Apr-06, 02:00 PM
Astromark's question in OTB had me thinking:

In a pulverizing lunar impact, would it be posible to form an Iapetus-style equatorial ridge, or would all the entry speeds be too fast and we would end up with an equatorial "lava provence" or maria?

2012-Apr-06, 02:12 PM
I think it depend on how long the surface stayed above the melting temperature of rocks.

2012-Apr-06, 02:36 PM
3000 odd degrees F? That probably wouldn't be hard to attain in those circumstances

2012-Apr-06, 02:46 PM
I bet that the debris from the moon would fall away from the earth instead of down on to the surface. I wish to state my opinion before an expert shows up to see if see if my logic is consistent with "reality."

(edit - I forgot to hit post. So my post is after the fact... sorry.)

Jeff Root
2012-Apr-06, 03:13 PM
I think antoniseb has in mind the idea that liquified
debris (lava) would flow back into the crater, forming
something like the lunar maria, while rapidly-cooling
debris would solidify before it could flow, and preserve
a larger, taller mountainous ring. Smaller bodies with
lower gravity might be surrounded by less dust and
vapor, and thus cool rapidly by radiation into space.

I expect that the material makes a big difference, as
well as the size and kinetic energy of the impactor.
High-energy impact would create a lot of vapor, while
low-energy impact might just throw out big chunks.

-- Jeff, in Minneapolis

2012-Apr-06, 03:24 PM
Thanks Jeff... yes, that plus the fact that after the Moon-creating collision the Earth and Moon both had very plastic surfaces for a long time. I was thinking (and failed to state explicitly) that Iapetus was a cold hard surface with low gravity. Even cold, I imagine that such a ridge on the Earth would (by its weight) morph the crust and be absorbed... but that last bit isn't part of what I was trying to say above.

2012-Apr-08, 03:00 AM
Glad you all jumped into this discussion.. but why start a 'new' thread..

You have turned me into some sort of ignorant troll rushing about chasing what is the same subject..

I am pleased to follow.... but. Now where did I put that ?

I asked some of these questions.. in 'Smashed Moon' .

2012-Apr-08, 03:18 AM
I have found some comment on this from a different view.

"That a debris field would create a ring around earth and over a thousand or so years would re emerge as a single moon..

That very little debris would leave the orbit it is now in.. It might get spread out, but not completely disrupted..

The Earth bound observer might not need fear such a event.. Just enjoy the display.." From and Quoted,. Patrick Moore.