Ernesto Guido & Nick Howes
Tue, 12 Feb 2013 21:59 CST
Asteroid 2012 DA14
was discovered by J75 OAM Observatory, La Sagra
on images taken on February 23.03, 2012 with a 0.45-m f/2.8 reflector + CCD.
2012 DA14 has an estimated size of 40 m - 90 m (based on the object's absolute magnitude H=24.09) and it will have a close approach with Earth at about 0.09 LD (Lunar Distances = ~384,000 kilometers) or 0.0002 AU (1 AU = ~150 million kilometers) at 1925 UT on 2013 Feb. 15.
2012 DA14 will pass only ~ 27,700 km (17,200 mi) above the Earth's surface, that is only 0.09 lunar distances or 5.4 Earth radii from the center of the Earth. So close that it will pass inside the ring of geosynchronous weather and communications satellites (located about 35,800 kilometers (22,200 miles) above the equator, but still well above the vast majority of satellites, including the International Space Station). Due to the extremely close approach, this object will be a very strong radar target at Goldstone where observations are scheduled on 2013 Feb. 16, 18, 19, and 20. Radar images should provide constraints on the size, shape, and rotation state of the object.
© NASA/JPL Near-Earth Object Program Office
This asteroid will reach the peak magnitude ~7.4 on February 15 around 1940 UT and it will be brighter than 9th magnitude for approximately 3 hours (18h00-21h30 UTC). At the moment of the close approach 2012 DA14 will move at ~ 2800"/min (slightly less that 1 degree per minute). The animated gif here
made by Geert Barentsen indicate (green areas) parts of the world where the asteroid will be above (and the Sun below) the horizon.
While there is no cause for concern ( 2012 DA14 will NOT impact Earth), this is one of the closest approaches recorded and the record close approach for a known object of this size. The table below shows the top 20 closest approaches by NEOs (Near-Earth Objects) sorted by nominal distance (click on the image for a bigger version).
The table below shows the top 20 closest approaches by NEOs (Near-Earth Objects) sorted by nominal distance + absolute magnitude H < =26. (click on the image for a bigger version).
According to JPL website "on average, we expect an object of this size to get this close to the Earth about once every 40 years. An actual Earth collision by an object of this size would be expected much less frequently, about once every 1200 years on average".
We plan to image 2012 DA14 during its close approach so stay tuned!