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| This computer image from a NASA video shows the small asteroid 2012 DA14 on its path as it passes by Earth on Feb. 15. (Picture from: http://www.npr.org/) |
The asteroid is a relatively small solid rock that orbits the sun. Asteroids in the group of small objects in the Solar System. There are millions of asteroids in the Solar System. The majority of the population of asteroids in the asteroid belt between the orbits of Mars and Jupiter. However, another asteroid families appear in significant numbers, such as near-Earth asteroids.
Near-Earth Asteroid (NEA) are asteroids whose orbit crosses and approaching the Earth's orbit. The asteroid that actually traverse/cutting Earth orbital trajectory known as Earth-crossers. During May 2010, a total of 7,075 near-Earth asteroids and successfully identified near-Earth asteroids with a diameter of more than one kilometer was estimated at 500 to 1,000.
One of near-Earth asteroids is the asteroid 2012 DA14. The asteroid 2012 DA14 details are still a little. This asteroid has an estimated diameter of about 45-50 meters and a mass of about 180,000 metric tons. The composition of the asteroid's shape is not known with certainty, but it is expected an S-type asteroid class means formed from silicate material. 2012 DA14 asteroid was found on February 23, 2012 by the Observatorio Astronomico de Mallorca (OAM), La Sagra, Spain seven days after the passing at a distance of 2,600,000 kilometers from Earth on February 16, 2012.
On January 9, 2013, 2012 DA14 asteroid discovered and observed again by the Las Campanas Observatory in Chile. From the findings and observations is obtained that the February 15, 2013 at 19:25 Universal Time (which is the standard time based on the rotation of the Earth) asteroid will pass at a distance of 34,100 kilometers from Earth's center point with the uncertainty region about 150 kilometers. In other words, the 2012 DA14 asteroid will pass at a distance of approximately 27,700 kilometers above the Earth's surface.
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| Nevertheless, it is a close call. The nearest the flying object will come to the earth is 27,600 km. It is indeed close shave in astronomical terms, because some of our communication satellites fly above this mark at 36,000 km. (Picture from: http://indiatoday.intoday.in/) |
The asteroid 2012 DA14 will be in the Earth-Moon system for about 33 hours. The asteroid will only reach a distance of 27,700 kilometers above the Earth's surface on February 15, 2013 at the night time about 07:30 GMT (Greenwich Mean Time). This distance is outside the Earth's atmosphere, but it was in the belt of artificial satellite orbit (geosynchronous orbit) which is approximately 35,800 kilometers above the Earth's surface. Indonesia has the closest distance to see the asteroid 2012 DA14.
The closest point to the Earth it is only about 21,000 kilometers. The asteroid is approaching from below the Earth (from the southern sky) and passes between the outer satellite constellation in geosynchronous orbit. When approaching the Earth, the asteroid 2012 DA14 will pass over the eastern Indian Ocean, off the coast of Sumatra. Thus, Indonesia has become the best place to see the asteroids that pass near Earth.
The asteroid 2012 DA14 will not be seen with the naked eye, but in a short time will peak rate / size on the magnitude of apparent brightness (apparent magnitude) 7.4 rough. Almost in all parts of Indonesia to see asteroid 2012 DA14 using the telescope. If good weather, this asteroid will look like a faint star crossing relatively quickly in the sky from the Northeast toward the Southwest. The asteroid 2012 DA14 can also be seen from some other parts of Europe, Australia, and Asia. Goldstone Observatory in the Mojave Desert, California, USA, will be watching the asteroid 2012 DA14 from February 16 until February 20, 2013.
Because of its trajectory, the asteroid 2012 DA14 does not have the opportunity through the Earth's shadow or collide with Earth. But if the asteroid such as the asteroid 2012 DA14 entered the Earth until then expected to release around 2.5 megatons of energy into the atmosphere and cause huge damage in the surrounding area. Such conditions would be similar to the Tunguska event was a massive explosion that occurred near the Podkamennaya (Under Rock) Tunguska River in what is now Krasnoyarsk Krai of Russia, at 7:17 AM on June 30, 1908.
The event is sometimes referred to as the Great Siberian Explosion, The explosion was most likely caused by the airburst of an ~20 m asteroid or piece of a comet 5 to 10 kilometers above the Earth’s surface. The energy of the blast was later estimated to be between 10 and 20 megatons of TNT, which would be equivalent to Castle Bravo, the most powerful nuclear bomb ever detonated by the US. It felled an estimated 80 million trees over 2,150 square kilometers.
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| The Tunguska event is the largest asteroid impact event in recent history. (Picture from: http://photo-mond.t2i.info/) |
An overhead satellite view, from nearly a century later, centered at 60°55′N, 101°57′E (near ground zero for this event) shows an area of reduced forest density, with a fully visible irregular clearing of somewhat less than one square kilometer in area.
Meanwhile, the chances of the asteroid 2012 DA14 affect satellites or spacecraft is very small because while the asteroid approaching the Earth and passed between the outer satellite constellation in geosynchronous orbit and the satellites concentration is much closer to the Earth. There was also a statement of the scientists that the asteroid could disrupt mobile phone, because this asteroid could collide with one of more than 100 telecommunications and weather satellites at geosynchronous orbit. However, NASA scientists ensure there's no communication, weather or GPS satellites are on the track of the asteroid 2012 DA14 when approaching the Earth.
Genesis pass-close will result in orbital period of the asteroid 2012 DA14 reduced from 368 days to 317 days, change the asteroid's origin Apollo orbital class to the Athene, and follow the pattern of the near-Earth passes different in the future. The asteroid 2012 DA14 will approach the Earth again on February 15, 2046 when the asteroid is passing at a distance no closer than 1,500,000 kilometers from the Earth's center point. *** [EKA | FROM VARIOUS SOURCES | DEDE NURROSYID | PIKIRAN RAKYAT 14022013]
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