Asteroid 2009 UN3 Close Approach - February 9th 2010

This asteroid is just under a kilometer in size and will pass within 14.5 times the distance from the Earth to the Moon. is should be visible in moderate or larger size telescopes near the border of the constellations Lepus and Columba. It will be a little easier to see in the southern hemisphere, where it will have an apparent movement of 50 arc seconds per minute, nearly fast enough to see the movement in the telescope.

(Asteroid 2009 UN3 Information)

This asteroid was discovered on Oct 19, 2009 by the Siding Spring Survey in Australia. 2009 UN3 has an absolute magnitude of 17.7, suggesting a diameter within a factor of two of 920 meters, but otherwise, nothing is known about its physical properties. 2009 UN3 will approach within 0.037 AU (14.3 lunar distances) on February 9, 2010, when it will be a strong radar target. Using recent experience as a guide,
there is a 1/6 chance that it's a binary system.

2009 UN3 is currently a southern sky object and its declination  remains south of -30 deg until after Feb. 8.
We have three days scheduled for this object at Goldstone (Feb. 8, 9, and 11).

2009 UN3 has been classified as a "Potentially Hazardous Asteroid" by the  Minor Planet Center.

 Orbital and Physical Characteristics  
 orbit type               Apollo
 semimajor axis           2.328 AU     
 eccentricity             0.58
 inclination              37.4 deg      
 perihelion distance      0.987 AU     
 aphelion distance        3.669 AU     
 absolute magnitude (H)   17.7
 diameter                 0.92 km   (plus/minus a factor of two)
 rotation period          8.4 h (Joe Pollock, private comm.)
 pole direction           unknown  
 lightcurve amplitude     0.35 (Joe Pollock, private comm.) 
 spectral class           unknown

Last update: 2010 Jan 24 (Check this page for further updates as the event progresses)