Near Earth Asteroids
Potentially Hazardous Asteroids (PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time.
On February 12, 2011 there were 1196 potentially hazardous asteroids.

Recent & Upcoming Earth-asteroid encounters:

Asteroid Date(UT) Miss Distance Size
2011 CA7 Feb 9 0.3 LD 4 m
2011 CZ3 Feb 10 2.5 LD 24 m
2003 YG118 Feb 20 67.7 LD 1.8 km
2000 PN9 Mar 10 45.5 LD 2.6 km
2002 DB4 Apr 15 62.5 LD 2.2 km
2008 UC202 Apr 27 8.9 LD 10 m
2009 UK20 May 2 8.6 LD 23 m
2008 FU6 May 5 75.5 LD 1.2 km
2003 YT1 May 5 65.3 LD 2.5 km
2002 JC Jun 1 57.5 LD 1.6 km
2009 BD Jun 2 0.9 LD 9 m
2002 JB9 Jun 11 71.5 LD 3.2 km
2001 VH75 Jun 12 42.2 LD 1.1 km

Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU.

David Cottle

UBB Owner & Administrator