joaa1epq5mh
hulajnoga
Dołączył: 25 Mar 2011
Posty: 28
Przeczytał: 0 tematów
Ostrzeżeń: 0/10
Skąd: England
|
 Wysłany: Pon 9:16, 11 Kwi 2011 Temat postu: coach laptop bag Apophis and the En coach laptop b |
|
|
On June 19, 2004, the telescope atop Kitt Peak in Arizona saw something no one else had ever seen before. It was a space rock that seemed to be on a collision course with Earth. This asteroid, originally named 2004 MN4 [link widoczny dla zalogowanych], was eventually renamed Apophis, a Greek word that means "Destroyer". The discovery of this asteroid was confirmed in December of that year by the Minor Planet Center, the clearinghouse for all such objects.
Further observations of Apophis allowed more refinement in the calculations of its orbit. It was then discovered that the next close pass would not result in an impact with Earth, but the information was not all good. The April 13, 2029, pass will be even closer than any of the original predictions -- so close that Earthly inhabitants will be able to watch Apophis sailing by with their naked eye. And there was fear that this phenomonally close approach would change Apophis's orbit, bringing it within range of striking Earth exactly seven years later.
Apophis made the public aware of the real threat that asteroids and other space objects can pose to life on Earth. Although Apophis is no longer a concern, there are countless unknown asteroids gliding in and out of Earth's space all the time. Any one of them could have our name on it. As the saying goes, "It's what you don't know that can kill you." Therefore, astronomers and amateurs are working to find, track, catalog, characterize, and determine the risk of all Near Earth Objects.
The trajectory of the asteroid was then calculated from the rough data available at the time. The results indicated that Apophis's next close approach would be on April 13, 2029, when it would come so close as to have a 1 in 37 chance of colliding with the Earth. (This date also happens to be Friday the Thirteenth.) As the orbit was calculated, the initial estimates of Apophis hitting Earth became more dire until it ranked a 4 on the Torino scale. The Torino Impact Hazard Scale is a way to chart the danger of space objects to life on Earth. A ranking of zero equals no hazard, a ranking of one indicates a pass by Earth but with no danger expected. Levels two through four are said to "merit the attention of astronomers," meaning that further observations are required but the likelihood is that the space object will eventually receive a ranking of zero. Levels five through seven are "threatening" and levels eight through 10 indicate a certain collision. Before Apophis, there had never been a space object rated above one on the Torino scale.
Read on
Asteroid Might Hit Mars
Danger from Near Earth Objects
Asteroid Presents Danger to Earth
One strike against them is the funding for the Arecibo Telescope. Arecibo, the largest and most sensitive radio telescope in the world, is used to characterize Near Earth Objects. It is in question who is responsible for the funding of the telescope: NASA or NSF, both of whom have shelled out for it in the past. If funding does not arrive soon, Arecibo will operate under reduced hours in October 2007 and be shut down after Sep
As of late 2006, extensive observations with radar [link widoczny dla zalogowanych], Doppler, optical, and past history data have led astronomers to conclude that there will be no impact with Earth in the foreseeable future. Apophis has been dropped to a zero on the Torino scale.
On April 13, 2036, Apophis is expected to make its next swing by Earth. The fear was that, during its 2029 approach, it entered a gravitational keyhole that would change its course and cause it to impact Earth on its next pass. So while the Torino rating was scaled down after discovering the 2029 impact would not happen [link widoczny dla zalogowanych], it remained at level one due to future questions.
Post został pochwalony 0 razy
|
|
