On February 15th, 2013, the astroid dubbed 2012 DA14 will pass by the earth inside the geosynchronus orbits of weather and communications satellites. Although it flies by the planet very close, there is no chance that the asteroid could impact the planet.
2012 DA14 is approximately 150 feet in diameter and will reach its closest distance to earth at 10:24 am Alaska Time. It will pass by the planet at about 4.8 miles per second. To put the passing in perspective, the asteroid will be as far away as over two diameters of the earth away, or about 1/10 the distance from earth to the moon traveling at 17,450 miles per hour.
The visitor’s orbit around the sun is roughly the same as the earth’s, and it makes relatively close approaches twice per orbit. What makes this flyby so special is that it is the closest predicted approach by an object in space this large. The asteroid will be within the earth/moon system for approximately 33 hours.
The 150 in diameter, 130,000 metric ton object will not be observable to the naked eye. The apparent magnitude is expected to peak at 7.4. In order to see the object, binoculars or a moderately powered telescope is necessary.
Although there is no chance of this asteroid impacting the planet currently, if an object of this size were to enter the atmosphere, it would be comparable to the Tunguska Impact in Siberian Russia on June 30th, 1908. The impact would release about 2.5 megatons of energy into the atmosphere and flatten over 800 square miles of the earth’s surface causing regional devastation.
The scientists at NASA’s Near-Earth Object Program Office estimate that an object of this size flies this close to the planet every 40 years or so. This flyby will be a great opportunity for science as optical telescopes the world over will be wacthing the object attempting to determine its spin rate and composition. NASA’s Goldstone Solar System Radar, that is situated in the Mojave Desert, will be tracking and observing 2012 DA14 as well, taking digital pictures.