Thursday, May 25, 2006

HOW WE GOT A MOON


The moon was formed about 4.5 billion years ago. Simulations performed by researchers at Southwest Research Institute TM (SwRI) and the University of California Santa Cruz show that a single impact by a Mars-sized object in the late stages of Earth/ formation account for an iron-depleted Moon and the masses and angular momentum of the Earth-Moon system.

The "Giant Impact" theory has been know and accepted by scientists for more than a decade because it proves an explanation for the low density of the moon. About 50 million years after the birth of the solar system, a planet of the size of Mars collided with the proto-earth. At this time the Earth was in the latter stages of its formation and had about 90% of the mass it has today. Due to the enormous mass involved the collision must have been very energetic.
Most of the mass of the earth probably melted and major portions would have evaporated.
The debris from the collision formed a ring around the earth, out of which the moon was born.
Subsequently, the moon moved further away from the earth and slowed down the rotation of the earth. The processes are still on-going. You can read the rest of this at http://www.spaceref.com/news/viewpr.htlm?pic=5773

So that is why earth rocks from the asteroid bombardment 3.8 billion years ago will still be found on the Moon and why Mars rocks can be found on Earth from the same asteroid bombardment.

5 comments:

R H said...

Hello Miss Jahteh. Yes well I'm down to three blogs - Yourself, Miss Brownie and Miss Pavlov, which are the only blogs worth commenting on anyway. And all of them ladies too. How nice. That's right. Well RH has been accused before of harrassing the ladies, and it's true. Yes, but it just happens that male blogs are incredibly boring. I don't know why they bother.
Good heavens, the way they go on. Hot air. Total shit.

Enough to make the moon leave cyberspace.

R.H.
(On topic)

JahTeh said...

I saw all your farewells but as I said you may have ranting rights here. I hope you're still going to lurk we'd miss that biting wit.

R H said...

I might start my farewells all over again.
I enjoyed them so much.

And of course my above comment didn't include the blokes who post here. The blokes who post here are actually very good. Funny. And interesting. You seem to attract the best commenters. Especially RH. Why is that?
I don't know. But it doesn't matter.

Brownie said...

Blue Moon, you saw me standing alone ...

Moonlight & Roses

Moon River

and Anonymous Moony will be the next comment to tell you where you were wrong in that post ... *cackles*

Re previous post on toothbrush:
the G-G got the song wrong - he might have used Octopus's Garden.

an an an - he obviously wasn't watching me gutz the flourless chocolate cake at his party. The pav I never touched honest, had kiwifruit which gives me the old anaphylactics.

JahTeh said...

How come I didn't get a photo of the choc cake? I will make you a pav like no other, coffee cream, mixed with mint chips, drizzled over with melted chocolate. Lord, I think I just described RH.