How to see Asteroid 2012 DA14
Expert satelliteer Greg Roberts of Cape Town, despite horrible light pollution, imaged the flyby of 2012 DA14.
The image on the right is a composite of several 3-second exposures, taken with a FLI8300M CCD camera, and shows the asteroid moving across the field of view of Greg's stationary 102-mm f/5 Skywatcher refractor.
"Magnitude was about +8.9," Greg writes, and "elevation about 13-14 degrees - very heavily light polluted sky! Despite flat fielding, dark frame and bias frame corrections I couldnt overcome the defects caused by the very poor background glow."
Greg has compiled a nice video showing the movement of the asteroid; watch it on YouTube at
Asteroid 2012 DA14 zips past Earth and through the southern skies on the evening of February 15. A steady pair of binoculars, a watch, and a star chart are all you need to see this cosmic bullet, lickety-splitting it 28,000 km/h past our planet.
2012 DA14 is an Aten-class Near-Earth Object, and was first seen on 2012 February 23. On 2013 January 09 is was picked up again and a more precise orbit could be built. Now the money is on Friday, 2013 February 15, at 21:25 SAST, when it will be a mere 34 052 km from Cape Town. This is more than 10 times closer to us than the Moon will be at that moment (395 610km)!
The finder chart below shows its rapid motion through the southern skies. The position of the asteroid is plotted at 15-minute intervals; see the table below for exact values, courtesy of JPL's HORIZONS.
Finder chart. Right click and SaveAs, then print out and use.
Ephemeris for asteroid 2012 DA14
|2013-Feb-15||19:00||11 44 17.02||-71 12 15.7||Mus||10.31||66 126|
|2013-Feb-15||19:15||11 49 30.00||-67 58 19.7||Mus||10.03||61 001|
|2013-Feb-15||19:30||11 53 54.66||-64 09 06.5||Cen||9.73||56 027|
|2013-Feb-15||19:45||11 57 41.04||-59 35 55.5||Cru||9.41||51 256|
|2013-Feb-15||20:00||12 00 57.28||-54 08 04.8||Cen||9.06||46 762|
|2013-Feb-15||20:15||12 03 50.28||-47 33 13.5||Cen||8.69||42 648|
|2013-Feb-15||20:30||12 06 26.19||-39 39 06.1||Cen||8.32||39 054|
|2013-Feb-15||20:45||12 08 50.75||-30 17 48.5||Hya||7.95||36 157|
|2013-Feb-15||21:00||12 11 09.38||-19 33 14.4||Crv||7.62||34 158|
|2013-Feb-15||21:15||12 13 27.00||-07 48 49.6||Vir||7.38||33 240|
|2013-Feb-15||21:30||12 15 47.46||+04 12 21.0||Vir||7.28||33 507|
|2013-Feb-15||21:45||12 18 13.11||+15 40 52.6||Com||7.34||34 937|
|2013-Feb-15||22:00||12 20 44.65||+25 59 28.5||Com||7.55||37 391|
|2013-Feb-15||22:15||12 23 21.70||+34 51 48.0||CVn||7.83||40 673|
|2013-Feb-15||22:30||12 26 03.37||+42 18 43.3||CVn||8.14||44 589|
|2013-Feb-15||22:45||12 28 48.76||+48 30 06.0||CVn||8.45||48 974|
|2013-Feb-15||23:00||12 31 37.17||+53 38 25.0||UMa||8.75||53 702|
The asteroid will be visible in binoculars from 19:30 onwards (near Musca and Crux) or 20:30 onwards (between Centaurus and Hydra), depending on where in South Africa you are.
By 21:00 it will be mag 7.6 and very easy to see - but will be very low above the horison for southern observers.
The best bet would be to pick it up at 20:30 in the south-east and follow it as it moves across Hydra and towards Corvus.
For those in the far north, it will be a 7.5-mag "star" within the beautiful Coma Berenice Star Cluster around 22:00.
(JPL press release by Paul Chodas and Don K. Yeomans)
This is the closest approach of this little world (estimated about 45 metres from tip to tip) in recent centuries -- see the graph below. Its next-closest visit was in 1919 (Feb 17) when it came to within 431,100 km of the Earth (more than 10 times further than the Feb 15 event). The graph shows the distance, in millions of kms, from 1913 to 2087. During this time, its closest approach to the Moon is on 2013 Feb 16 at 02:41 (409,434 km), while its closest approach to Venus will be on 2050 Feb 11 at 11:37 (16.42 million km).
Data for this graph from http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012%20DA14;orb=0;cov=0;log=0;cad=1#cad
nothing more to see. please move along.