Skip to comments.Earth's Moon is 'cosmic rarity'
Posted on 11/21/2007 1:12:51 PM PST by Aristotelian
Moons like the Earth's - which are formed in catastrophic collisions - are extremely rare in the Universe, a study by US astronomers suggests.
The Moon was created when an object as big as the planet Mars smacked into the Earth billions of years ago.
The impact hurled debris into orbit, some of which eventually consolidated to form our Moon.
The Astrophysical Journal reports that just 5-10% of planetary systems in the Universe have moons created this way.
(Excerpt) Read more at news.bbc.co.uk ...
Lots of paths to the same ends...
This was claimed by Zecharia Sitchin in his Book The 12th Planet published in 1976.
I’m the same way. I look to science and astronomy as all the evidence of God that I need.
... and where did that Mars-sized object come from, and where did it go? Answer that, Sagan!!!
Mars appears to have had a planet of its own at some time. That is, Mars would have been the moon of that system. What happened to its planet is not clear although it is possible some of it is in the Asteroid Belt and a piece of it could have been the body that nearly hit earth creating the moon.
It couldn’t have happened billions of years ago. The earth is only 6,000 years old.
Indeed the moon could have been wondering around the universe for billions of years, and when G*d created the earth, the gravitational pull of the new planet snagged the moon into place.
Carl is unusually silent today.
Perhaps as rare as it having the same angular dimensions as the Sun at Earth’s surface, thus providing a “perfect” solar eclipse to us mere mortals at this time in history...
A momentary circumstance, an instant on the cosmic timescale. The moon is already gone, escape velocity achieved.
When the Days Were Shorter
Alaska Science Forum (Article #742) | November 11, 1985 | Larry Gedney
Posted on 10/04/2004 1:31:59 PM EDT by SunkenCiv
New evidence for the Moon’s soft middle
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Posted on 12/27/2004 5:29:35 PM EST by SunkenCiv
In the shadow of the Moon
New Scientist | 30 January 1999 | editors
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Did an ancient impact bowl Pluto over?
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Posted on 10/30/2007 10:29:02 PM EDT by SunkenCiv
Red Planet’s Ancient Equator Located
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Posted on 04/24/2005 11:18:25 PM EDT by SunkenCiv
The Moon produces slightly more than half of the tides — the rest are produced by the Sun. So, no, the Moon isn’t necessary for the Earth to have tides.
The South Pole-Aitken basin (circled) is the largest impact crater in the solar system. One edge lies on the Moon's south pole, while its centre lies about 30° away (Image: Clementine Project/LPI)
Did the new moon lose its iron heart?The current theory says that the material that now forms our moon was ejected when Earth was struck by another planet-sized body. But Peter Noerdlinger at Saint Mary's University in Halifax, Canada, says this theory has problems. "The collision has to be implausibly gentle. You practically need someone to hold a Mars-sized object just above Earth and drop it, to avoid messing up Earth's orbit."
January 23, 2007
The simpler idea that Earth and the moon were both created from the same gas cloud had been rejected because it could not explain why Earth formed an iron core and the moon did not. Now, Noerdlinger has an answer for that.
He suggests that the proto-moon did have an iron core, but that the satellite was ripped apart in a close encounter with Earth. His calculations show that iron from the core would be pulled towards Earth, while the remains of its rocky outer shell reassembled into our iron-free moon.
This fits with evidence that the Earth acquired a veneer of iron after it formed, Noerdlinger says. He presented the work at the American Astronomical Society meeting in Seattle, Washington, last week.
From issue 2587 of New Scientist magazine, 23 January 2007, page 16
The primary reason that I say that is because we only recently discovered that there are literally a billion other galaxies, and at this point we have only surveyed a few dozen or so with telescopes of different varieties and only a couple of those are close enough to determine that some of the systems have one or more planets.
We are not close enough to any of those to determine how many or what kind of moons they may have, and certainly not how they were formed. We can only prove that some sort of planet exists because of orbital anomalies in their suns. We cannot actually see any planets at all, much less moons.
Collisions must be common during the formation of galaxies and their planetary systems because everything starts out as a compact cluster of gas and building block materials. Collisions are a part of that formation and not only do they occur, they must occur.
Nope.....the moon is not all that special to anyone but us. Sure it is important to Earth and it's ability to grow so much life, but their certainly could be billions of other Earths in the universe.....Billions (in my most humble opinion)
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