Scanning electron microscope picture of a glass spherule brought back from the Moon by Apollo 11. The spherule is about 250 microns in diameter. Photo by Tim Culler/UC Berkeley
Posted on 11/27/2006 10:11:37 PM PST by SunkenCiv
In the March 10 issue of the journal Science, researchers with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley (UC Berkeley), and the Berkeley Geochronology Center (BGC) announced the discovery that impact cratering on the moon (and, by inference, on the earth) suddenly increased about 400 million years ago... The data published by this team show that the impact cratering rate had dropped steadily until the unexpected rise when the impact rate returned to the same levels as 3.5 billion years ago. The sudden increase coincides with the "Cambrian explosion," a period in which life on Earth took off with a dramatic burst in the number and diversity of species... Noting that the earliest records of life on earth date from the period approximately 3.5 billion years ago, when their results show the intensity of impacts was decreasing, Renne says: "Maybe, as others have speculated before, life began on Earth many times, but the comets only stopped wiping it out about three or four billion years ago."
(Excerpt) Read more at lbl.gov ...
Scanning electron microscope picture of a glass spherule brought back from the Moon by Apollo 11. The spherule is about 250 microns in diameter. Photo by Tim Culler/UC Berkeley
...a nice, fresh, new catastrophism ping list topic, from 2000. ;')
Nemesis: Does the Sun Have a 'Companion'?
SPACE dot COM | 03 April 2001 | By Robert Roy Britt
Posted on 02/10/2003 2:03:23 PM EST by vannrox
http://www.freerepublic.com/focus/f-news/839980/posts
http://www.space.com/news/nemesis_010410.html
Ping
"Even though we don’t know which crater was the source of each spherule, the distribution of the ages of the spherules from a single lunar site should reflect the age distribution of craters on the Moon," Muller said.
I would assume the single sample could come from an area "bombarded" at the measured peak age of the sample. I would be convinced if a sample gathered at the antipode displayed the same profile.
;^)
I thought the "Cambrian Explosion" was supposed to have happened 600 million years ago, not 400. Who changed the dates?
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