Asteroid 2012 DA14 to Buzz the Earth

On Friday 15th February the recently discovered Apollo-class near-Earth asteroid 2012 DA14 will make a close pass by the Earth. The asteroid will come within about 34,000 km (21,000 miles) of the centre of our planet at 7.26 p.m. That is, within the ring of geostationary communication satellites which orbit at some 35,800 km above the surface of the Earth. Geostationary satellites orbit the Earth once a day remaining more or less stationary above a single location on Earth and appearing stationary in the sky, thus able to relay communications around the world.

The asteroid 2012 DA14, was discovered by a team of amateur astronomers at the Observatorio Astronomico de La Sagra, near Granada in southeast Spain, on the night of 22/23 February 2012. The orbit is Earth-like with a period of 366.24 days, that is one day longer than the EarthтАЩs year. DA14тАЩs orbit is inclined to the EarthтАЩs orbit around the Sun by a little over 10 degrees and has an eccentricity of about 0.11. The asteroid will not be visible to the unaided eye but will have a maximum apparent magnitude of 7.4, in other words nearly four times fainter than the faintest objects visible with the normal naked eye. Still, the asteroid should be visible with the aid of binoculars or a small telescope.

This object is one of the brightest known Earth-approaching asteroids of any substantial size to have passed so close to Earth in recent years. With an estimated size of the order of 50 metres in diameter, it is comparable in size to the object that destroyed over 2,000 square kilometres of forest in Tunguska, Siberia, on 30th June 1908. Although 2012 DA14 appears to have no significant chance of colliding with our planet in the future, astronomers will continue to track its orbit with the object of determining and monitoring its future trajectory, following the close approach on 15th February.

During the evening of 15th February, 2012 DA14 will travel across the sky at a fairly high angular speed, passing through the handle of the Plough, in the northeast, at about 21:30 hours by which time its brightness will be fading rapidly. The next known similarly close approach of an asteroid of substantial size is that of Apophis, approximately 300 metres across, which too will pass within the region of the geostationary satellites, on Friday 13th April 2029.

FOR FURTHER INFORMATION PLEASE CONTACT: John McFarland at the Armagh Observatory, College Hill, Armagh, BT61 9DG. Tel.: 028-3752-2928; FAX: 028-3752-7174; jmfarm.ac.uk.

This chart shows the position of 2012 DA14 in 30 minute intervals on the night of February 15th-16th from 20:00 (when it rises at magnitude 7.7) until 01:00 (magnitude 11.6). The asteroid's position is indicated by the red circles, which cover an angular size of 1.5 deg (i.e. 90 arcmin) on the sky. Stars down to magnitude 8 and deep sky objects down to integrated magnitude of 9 are shown.

Click on image for PDF version

Last Revised: 2013 February 11th