Posted on 02/10/2013 2:09:02 PM PST by BenLurkin
Earth's gravity may not have the gravitas of Jupiter, but the planet regularly plucks small asteroids passing by and pins them into orbit. The mini-moons don't stay for long. Within a year or so they resume their looping, twisting paths like crazy straws around the sun. But others arrive to take their place.
Simulations show that two asteroids the size of dishwashers and a dozen half-meter (1.6 feet) in diameter are orbiting Earth at any given time. Every 50 years or so something the size of a dump truck arrives. So far, there's been just one confirmed sighting.
...
A paper published last year showed that, in theory, a cloud of temporarily captured asteroids circles Earth at all times, but that the largest object is just about a meter (3 feet) in diameter.
"These are really difficult to detect with current technology," said astronomer Paul Chodas, with NASA's Near Earth Object program at the Jet Propulsion Laboratory in Pasadena, Calif.
So far, the only confirmed captured asteroid that orbited Earth was RH120, which most recently visited from September 2006 to June 2007. Initially, the object was suspected of being a spent upper-stage motor from an Apollo rocket, but follow-up observations by ground-based radars determined the object was not metallic.
"There is great interest in tracking these Temporarily Captured Objects (TCOs), because for a short time they are easily accessible for both scientific study and, possibly, eventually, resource utilization," Chodas wrote in an email to Discovery News.
In addition to being small, mini-moons are difficult to find because they only hang around for a relatively short time, between six and 18 months.
(Excerpt) Read more at news.discovery.com ...
I was reading that the earth’s crust contains something like 17% iron while many asteroids are believed to consist of 70% or more iron.
Its not a terribly expensive metal on earth but lifting it to orbit is extremely expensive.
I miss him.
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Got to go find a kerchief to wipe the screen now...
You can add zeroes to OMFG but its kinda pointless because you particles are sucked into the star or flung off the screen so fast you miss them if you blink.
Small Comets and Our Origins
University of Iowa | circa 1999 | Louis A. Frank
Posted on 10/19/2004 11:13:25 PM PDT by SunkenCiv
http://www.freerepublic.com/focus/bloggers/1250694/posts
Comet’s water ‘like that of Earth’s oceans’
BBC | October 5, 2011 | Jason Palmer
Posted on 10/05/2011 6:41:44 PM PDT by decimon
http://www.freerepublic.com/focus/news/2788555/posts
An Argument for the Cometary Origin of the Biosphere
American Scientist | September-October 2001 | Armand H. Delsemme
Posted on 09/06/2004 8:16:38 AM PDT by SunkenCiv
http://www.freerepublic.com/focus/chat/1208497/posts
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