Yeah, otherwise...
Posted on 02/27/2011 5:17:43 PM PST by SunkenCiv
It is possible that such a phenomenon could occur when matter around a newborn star forms into planets. In a planet's orbit around a star, there are two places where a third body can safely orbit. These spots, known as Lagrange points, are 120 degrees in front of and behind whichever body is smaller. The discovered co-orbiting planets, located in the four-planet system KOI-730, are always 120 degrees apart, permanent fixtures in each others' night skies.
Fifty million years after the birth of our solar system, the moon may have formed from the debris of a collision between Earth and a Mars-sized body named Theia. For this to be true, Theia would have to have hit earth at a relatively low speed. Richard Gott and Edward Belbruno of Princeton University say that this could only have happened if Theia had originated in a Lagrange point. The discovery of the KOI-730 planets shows that it is possible.
(Excerpt) Read more at popsci.com ...
Gee whiz, I have friends in the Astronomy Racket too! They sometimes talk out of school and give away the secrets.
These spots, known as Lagrange points, are 120 degrees in front of and behind whichever body is smaller.
Why not say "a Lagrange point is 120 degrees in front of and behind whichever body is bigger?" Regardless of which one is in front they will be 120 degrees apart according to what has been said here.
Some of the issues with the Theia hypothesis:
The ratios of the Moon’s volatile elements are not explained by the giant impact hypothesis. If the giant impact hypothesis is correct, they must be due to some other cause.
There is no evidence that the Earth ever had a magma ocean (an implied result of the giant impact hypothesis), and it is likely there exists material which has never been processed by a magma ocean.
The iron oxide (FeO) content (13%) of the Moon, which is intermediate between Mars (18%) and the terrestrial mantle (8%), rules out most of the source of the proto-lunar material from the Earth’s mantle.
If the bulk of the proto-lunar material had come from the impactor, the Moon should be enriched in siderophilic elements, when it is actually deficient in those.
The presence of volatiles such as water trapped in lunar basalts is more difficult to explain if the impact caused a catastrophic heating event.
The Moon’s oxygen isotopic ratios are essentially identical to those of Earth. Oxygen isotopic ratios, which can be measured very precisely, yield a unique and distinct signature for each solar system body, If Theia had been a separate proto-planet, it would probably have had a different oxygen isotopic signature than Earth, as would the ejected mixed material.
Somebody else posted it a few weeks back and it runs almost constantly when my computer is online.
One thing that seems to play out true is the fact that binary stars are common. Also interesting is the fact that supermassive objects fling small ones way out at astounding speeds.
I just wish it were far more detailed.
These spots, known as Lagrange points, are 120 degrees in front of and behind whichever body is smaller. The discovered co-orbiting planets, located in the four-planet system KOI-730, are always 120 degrees apart, permanent fixtures in each others’ night skies.
From the link in the linked article.
http://www.newscientist.com/article/dn20160-two-planets-found-sharing-one-orbit.html?DCMP=OTC-rss&nsref=online-news
Gravitational "sweet spots" make this possible. When one body (such as a planet) orbits a much more massive body (a star), there are two Lagrange points along the planet's orbit where a third body can orbit stably. These lie 60 degrees ahead of and 60 degrees behind the smaller object. For example, groups of asteroids called Trojans lie at these points along Jupiter's orbit.
Which is it, 60 or 120 degrees? I can't finish my school project until I find out!
The L4 & L5 points are stable. The other three are not.
Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)
They are some times collectively referred to as Trojan asteroids.
Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)
Neither. Think of it like spokes on a steering wheel.
The Lagrangians are the same three points, just that two of them are occupied by planets.
You see the same thing, especially with Jupiter, Asteroids at both Lagragian points.
L2 and L3 are 60 degrees ahead or behind the most massive object.
And I see someone has already explained L4 and L5 lagrange points.
Maybe John Norman wasn’t as crazy as we thought (nah).
Back doors are not secrete Mr potatoe head
If so that event would pretty much obliterate all the surface evidence for the collision.
I'd like to note that the statement regarding "magama" in the Wiki article is kind of questionable since, in fact, Earth has a LARGE magma presence immediately under the tectonic plates ~ HUGE HUGE bunch of magma! Silica, calcium, phosphorous, et al, simply floats on top of it ~
I wholeheartedly agree that the Moon wasn’t born of the Earth, either through (non-nuclear) fission (TVF’s version is, born to relieve an overspin condition as the heavies sank to the early molten Earth’s core) or impact (the dominant paradigm). The Moon was captured by the Earth sometime in the last five percent of Earth’s existence.
It means that the writer of the article didn’t really understand what Lagrangian points are. :’)
“Why do we call asteroids asteroids and hemhorrhoids hemhorrhoids? Shouldn’t it be the other way around?” — Robert Schimmel
The need for low speed has to do with trying to make the scenario work at all. :’)
Well, you know... rumors run wild.
Sorry ZZTop
The paperbacks had some of the best sexist covers, ever. ;’)
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.
