Posted on 12/20/2007 1:37:02 PM PST by blam
Moon is younger and more Earth-like than thought
20:13 19 December 2007
NewScientist.com news service
Maggie McKee
It's a good thing the Moon doesn't have any feelings to hurt. New research suggests it is actually 30 million years younger than anyone had thought, and that it is merely a 'chip off the old block' of Earth rather than being made up of the remnants of a Mars-sized body that slammed into Earth billions of years ago.
That violent impact was thought to have taken place 30 million years after the solar system began to condense from a disc of gas and dust 4.567 billion years ago. The event was thought to have melted the Earth, generating a magma ocean that covered the planet and allowed iron and other metals to sink to its centre, forming a core.
At the same time, the Moon was thought to have coalesced from a disc of molten debris blasted off the Earth and the Mars-sized interloper.
But new research led by Mathieu Touboul of the Swiss Federal Institute of Technology in Zurich suggests that picture is not so simple. The researchers base their analysis on studies of an isotope of the metal tungsten in lunar rocks.
That isotope, tungsten-182, is produced by the decay of two other elements: hafnium-182, which has a half-life of 9 million years, and tantalum-182. Tantalum-182, however, is not an intrinsic component of the Moon – it forms when energetic charged particles from space, called cosmic rays, slam into the lunar surface.
Previous estimates of the Moon's age were based on tungsten measurements that did not subtract the effect of the decay of tantalum. "It is crucial to remove all the tungsten-182 coming from the cosmic-ray production," Touboul told New Scientist. "Otherwise, the age one
(Excerpt) Read more at space.newscientist.com ...
LOL, how does an event happening "4.567 billion years ago" fit into a young-earth perspective ?
Merry Christmas!
Thanks for the topic blam, and the ping DLR.
When the Days Were Shorter
Alaska Science Forum (Article #742) | November 11, 1985 | Larry Gedney
Posted on 10/04/2004 10:31:59 AM PDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1234919/posts
Did you get to see it last night?
Right next to the Moon!
Really neat!
New research suggests it is actually 30 million years younger... the Moon was thought to have coalesced from a disc of molten debris blasted off the Earth and the Mars-sized interloper... The researchers base their analysis on studies of an isotope of the metal tungsten in lunar rocks. That isotope, tungsten-182, is produced by the decay of two other elements: hafnium-182, which has a half-life of 9 million years, and tantalum-182. Tantalum-182, however, is not an intrinsic component of the Moon – it forms when energetic charged particles from space, called cosmic rays, slam into the lunar surface. Previous estimates of the Moon's age were based on tungsten measurements that did not subtract the effect of the decay of tantalum.Previous estimates (and those described in this article) are not based on the tungsten measurements, they are based on the bias that the Moon *must have* formed from an impact on the proto-Earth by a Mars-sized object.
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