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mick silver
23rd December 2015, 08:33 AM
Huge comets may pose ‘inevitable’ danger to Earth – astronomers Published time: 22 Dec, 2015 21:43
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The recent discovery of hundreds of giant comets in our outer solar system has prompted astronomers to sound high alert. They says the space bodies move on unstable orbits and can flood inner solar system making impacts of comet debris with Earth “inevitable.”
Researchers from Armagh Observatory and the University of Buckingham have warned on Tuesday that discovery of hundreds of giant comets in the outer planetary system over the last two decades raises the risk that life on our planet could be wiped out by comet debris, rather than an asteroid.
The research (https://www.ras.org.uk/news-and-press/2758-giant-comets-could-pose-danger-to-life-on-earth) published in the December issue of Astronomy & Geophysics (A&G), the journal of the Royal Astronomical Society, says that hundreds of giant comets – from 50 to 100 kilometers across, or larger – move on unstable elliptical orbits crossing the paths of the massive outer planets Jupiter, Saturn, Uranus and Neptune.
The planet’s gravitational fields have the potential to push the space bodies, also called centaurs, from their orbit to Earth.
“Whilst in near-Earth space they are expected to disintegrate into dust and larger fragments, flooding the inner solar system with cometary debris and making impacts on our planet inevitable,” the research team said.
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A single centaur contains more mass that the entire population of Earth-crossing asteroids discovered to date, the team added.
"In the last three decades we have invested a lot of effort in tracking and analyzing the risk of a collision between the Earth and an asteroid,” said Professors Bill Napier of the University of Buckingham.
“Our work suggests we need to look beyond our immediate neighborhood too, and look out beyond the orbit of Jupiter to find centaurs. If we are right, then these distant comets could be a serious hazard, and it’s time to understand them better."
READ MORE: NASA reveals images of ‘Spooky’ asteroid that zipped past Earth on Halloween (https://www.rt.com/news/320713-spooky-asteroid-flies-by/)
Astronomers’ calculations suggest that such a scenario could happen once every 40,000 to 100,000 years.
“Some of the greatest mass extinctions in the distant past, for example the death of the dinosaurs 65 million years ago, may similarly be associated with this giant comet hypothesis,” the team said after comparing specific episodes from our past identified by geologists and paleontologists.


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mick silver
23rd December 2015, 10:05 AM
This is the End: Outer Space Comets Could Destroy Humanity© Photo: Rex Features



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Astronomers warn that a threat from outer space is more possible than expected, and the sudden end of humanity may be caused not by climate change or space rocks regularly sailing by the Earth, but by a random escapee from the huge distant space bodies orbiting in the Oort Cloud, far beyond Neptune, currently the most distant planet from our Sun.

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Centaurs, massive space rocks orbiting on the outskirts of our Solar System, could be very hazardous to the Earth, a group of astronomers said Tuesday, as reported by Phys.org.These space bodies, composed of ice and dust, and being up to some 50-100 kilometers wide, were discovered several decades ago. Astronomers state that centaurs should be counted as a greater threat than comets, as the "assessment of the extraterrestrial impact risk, based solely on near-Earth asteroid counts, underestimates its nature and magnitude."
Bill Napier, an astronomer from the University of Buckingham, said that scientists have been thoroughly analyzing the possibility of a collision between the Earth and asteroids for the last 30 years, and have included distant celestial bodies, including centaurs.
"If we are right, then these distant comets could be a serious hazard, and it's time to understand them better," Napier claimed.

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The centaurs’ orbits, believed to be extremely unstable, cross inside the orbits of enormous gas giants like Jupiter, Saturn, Uranus and Neptune, about once every 40,000-100,000 years. When it happens, scientists say, the planets’ powerful gravity fields can deflect the centaurs toward the Sun.On their way to the Sun asteroids begin to fracture, ultimately turning into cometary debris which makes “impacts on our planet inevitable." Individual centaurs, they point out, can have an estimated mass higher than that of all the comets documented to date.
"The disintegration of such giant comets would produce intermittent but prolonged periods of bombardment lasting up to 100,000 years," researchers wrote in Astronomy and Geophysics, the journal of the Royal Astronomical Society.

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If comet debris enters the Earth’s atmosphere, astronomers suggest, it would cause a heavy meteor shower and trigger dramatic climate change, threatening life on the planet."A centaur arrival carries the risk of injecting, into the atmosphere… a mass of dust and smoke comparable to that assumed in nuclear winter studies," scientists said.


Under that scenario, humanity would follow in the footsteps of dinosaurs, believed to have died out as a result of an asteroid strike. And despite that there is no proof that a collision is imminent, “its ranking among natural existential risks [for humanity] appears to be high," some astronomers suggested.





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EE_
23rd December 2015, 10:22 AM
The only people this will pose ‘inevitable’ danger to, are the elite that have planned to rule over the people of earth for centuries in the future.
We are only here for a mere spec of time, many of whom only think forward to their next paycheck.

cheka.
23rd December 2015, 11:14 AM
what will that do to global warming?

mick silver
23rd December 2015, 11:36 AM
notice it on a lot of news sites . wonder why now you know theys seen this for years

Glass
23rd December 2015, 06:18 PM
they roll these things out on a regular basis. Like they do with the new possible maybe medical breakthrough cure news that gets rotated weekly. These doom things they seem to bring out on the holy days.