Thanks BenLurkin, and Merry Christmas.
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Posted on 12/23/2015 10:12:19 PM PST by BenLurkin
Most studies of potential Earth-smashers focus on objects in the asteroid belt roughly between Mars, Earth's outside neighbour, and Jupiter on its other flank, said the researchers.
But they noted that the discovery in the last two decades of hundreds of giant comets dubbed centaurs, albeit with much larger orbits, requires expanding the list of potential hazards.
These balls of ice and dust, typically 50-100 kilometres (31-62 miles) wide, have unstable, elliptical orbits that start way beyond Neptune, the most distant planet from the Sun.
Their paths cross those of the giant planets Jupiter, Saturn, Uranus and Neptune, whose gravity fields occasionally deflect a comet towards Earth - once about every 40,000-100,000 years.
As they draw closer to the Sun, the comets would gradually break up, which is what causes the trademark cometary debris tail - "making impacts on our planet inevitable".
"The disintegration of such giant comets would produce intermittent but prolonged periods of bombardment lasting up to 100,000 years," the research team wrote in the Royal Astronomical Society journal, Astronomy and Geophysics.
And they argued that "assessment of the extraterrestrial impact risk based solely on near-Earth asteroid counts, underestimates its nature and magnitude."
They noted that a single centaur contains more mass than the entire population of Earth-crossing asteroids discovered to date.
(Excerpt) Read more at news.discovery.com ...
ping
We’re DOOOOMED!
Oes Noes!!!!!
Caused by climate change.
Apparently Obama hasn’t axed enough of our space program yet for this to be in any way more important than global warming.
This just proves we should spend more time thanking GOD we are still here on the planet and less time fighting over what kind of hats men wear.
And the cure is — more taxpayer funding.
Seems that the system was older but reliable and accurate.
Here it is:
US 'Space Fence' Radar System Goes Silent, After 50 ... - NPR www.npr.org/.../u-s-space-fence-radar-system-goes-silent-after-50-year...NPR
Sep 3, 2013 - The military says the shutdown can save $14 million annually. ... to shut down the radar system that tracks thousands of objects orbiting Earth.
Shelton Orders Shutdown of Space Fence - SpaceNews.com spacenews.com/36655shelton-orders-shutdown-of-space-fence/
Aug 6, 2013 - WASHINGTON — The U.S. Air Force is shutting down a key part of its ... that the Air Force Space Surveillance System be closed and all sites ... is a line of VHF radars stretching across the southern United States.
... the VHF Space Fence is crucial because it can track objects up to 24,000 kilometers away.
It can also track incoming missiles.
150 quadrillion. Feel better?
Great name for a rock band - “Earth Smashing Space Rocks”. Sort of an interstellar name versus earthbound “Smashing Pumpkins” and “Smashmouth”.
Agreed.
Thanks BenLurkin, and Merry Christmas.
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I don’t think I understood a word of what I read. My bad. :o[
Merry Christmas, Ben! <3
Merry Christmas, you! <3
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