Massive Impact in the Kuiper Belt 4.5 Billion Years Ago
2007 03 29
In the outer reaches of the solar system, there is an object known as 2003 EL61 that looks like and spins like a football being drop-kicked over the proverbial goalpost of life.
Still awaiting a more poetic name, 2003 EL61 largely escaped the media hubbub during last year's demotion of Pluto, but new findings could make it one of the most important of the Kuiper-belt objects for understanding the workings of the solar system. In this week's Nature, the original discoverer of the body, Mike Brown, announces with his colleagues that an entire family of bodies seems to have originated from a catastrophic collision involving 2003 EL61 about the time Earth was forming.
Brown and his team base their assumptions on similar surface properties and orbital dynamics of smaller chunks still in the general vicinity. They conclude that 2003 EL61 was spherical and nearly the size of Pluto until it was rammed by a slightly smaller body about 4.5 billion years ago, leaving behind the football-shaped body we see today and a couple of moons, as well as many more fragments that flew away entirely.
"Some of these chunks are still in orbit around the sun and very near the orbit of 2003 EL61 itself," says Brown, a professor of planetary astronomy at the California Institute of Technology. "The impact made a tremendous fireball, and large icy chunks of the big object split off and went flying into space, leaving behind a huge ice-covered rock spinning end over end every four hours.
"It spins so fast that it has pulled itself into the shape of an American football, but one that's a bit deflated and stepped on," Brown adds.
A significant part of the finding is that the collision occurred in a region of space where orbits are not very stable. "In most places, things go around the sun minding their own business for 4.5 billion years and nothing happens," says Brown. "But in a few places, though, orbits go crazy and change and eventually objects can find themselves on a trajectory into the inner solar system, where they would be what we would then call comets."
As a consequence, many of the shards probably made their way to the inner solar system, and a few have undoubtedly hit Earth in the past. The study thus provides new ideas about how the solar system evolves, and how comets fit into the big picture.
Brown adds that 2003 EL61 will put on quite a show in about a billion years, if anyone is still around to enjoy it.
"It's a long time to wait, but 2003 EL61 could become by far the largest comet in eons," Brown says. "It will be something like 6,000 times brighter than Hale-Bopp a few years ago."
The other authors of the paper are Kristin Barkume, Darin Ragozzine, and Emily Schaller, all graduate students in planetary science at Caltech.
Article from: http://www.redorbit.com/news/space/880374/massive_
Velikovsky's Ghost Returns
Giant impact added to Earth's core
Solar system's unusual structure suggests existence of extraterrestrial civilizations
The Birth of Venus
A "mysterious" force is baffling scientists and making biological species evolve
Planetary Collisions and the Vatican
Pluto's out of the Planets club - In comes Eris (Goddess of discord)
The 'Galactic Mask' Unveiled
The Exploded Planet Hypothesis
Tut's gem hints at space impact
Libya's Kebira Crater
Latest News from our Front Page
EU on high alert as Germany accepts Ebola patients
2014 07 30
A German hospital has agreed to treat Ebola patients amid widespread fears of a possible outbreak of the deadly disease in Europe. Over 670 people have already been killed by the disease in West Africa with doctors struggling to control the epidemic.
A German hospital in Hamburg agreed to accept patients following a request from the World Health Organization (WHO), Deutsche ...
Bolivia declares Israel terrorist regime
2014 07 30
Bolivia has declared Israel a “terrorist state” and revoked a visa exemption agreement with Tel Aviv in protest at the ongoing Israeli attacks on the besieged Gaza Strip.
The move "means, in other words, we are declaring (Israel) a terrorist state," President Evo Morales said during talks with a group of educators in the city of Cochabamba ...
Pagan Traditions: Mysteries of medieval graffiti in England’s churches
2014 07 30
Medieval graffiti of straw kings, pentagrams, crosses, ships and "demon traps" have been offering a tantalising glimpse into England’s past. What do the pictures reveal about life in the Middle Ages?
A project to record the graffiti, which began in Norfolk, has now been rolled out to other areas and is gradually spreading across England.
Armed with just a torch and a ...
More Gigantic Holes Appear in Siberia’s ’End of the World’
2014 07 30
Is it the end of the world in Siberia’s ’End of the World’?
Scientists suspect not, but they’re still investigating the strange and alarming holes that are swallowing up the Siberian north.
This week two new holes have been discovered, and with similar characteristics as the first reported hole: a very deep shaft with smooth sides, debris surrounding the rim, and water ...
BLACKLISTED: The Secret Government Rulebook For Labeling You a Terrorist
2014 07 30
The Obama administration has quietly approved a substantial expansion of the terrorist watchlist system, authorizing a secret process that requires neither “concrete facts” nor “irrefutable evidence” to designate an American or foreigner as a terrorist, according to a key government document obtained by The Intercept.
The “March 2013 Watchlisting Guidance,” a 166-page document issued last year by the National Counterterrorism Center, ...
|More News » |