I was just sweeping through my archives and have found this interesting observation, which occured before the forum creation - on Jan.30, 2008.
Asteroid
2007 TU24 have passed by Earth at circa 08UT of Jan.29, 2008 at minimal distance 0.0037 AU = 550 000 km.
BTW here is that pretty picture from Arecibo
It was cloudy here in the evening, but fortunately it has cleared before dawn (although the temperature dropped to -9°C). I was able to catch the NEA between circa 04:30 - 05:15 EET in Ursa Major (altitude 60°) with my 76mm Newton @35x.
I have estimated its magnitude as
10.6m (ML=11.5m). Movement in front of the faint background stars was visible in 5-10 seconds (angular velocity ~1.6°/h). Geocentric distance at the moment of observation was ca. 0.0054 AU = 810 000 km.
Sketch
It was an unforgettable observation, and probably the smallest asteroid I have ever seen.
P.S. There will be only one visible return (I mean close return) in the future...
K07T24U
Date UT R.A. (J2000) Decl. Delta r El. Ph. V Sky Motion Uncertainty info
h m s "/min P.A. 3-sig/" P.A.
2046 01 20 000000 13 49 48.1 -70 09 37 0.014 0.980 72.4 106.8 15.0 47.53 344.2 N/A N/A
2046 01 21 000000 13 17 13.7 -51 44 16 0.015 0.982 82.2 96.9 14.6 44.85 351.4 N/A N/A
2046 01 22 000000 13 05 33.1 -35 42 11 0.017 0.985 91.7 87.3 14.4 35.48 353.5 N/A N/A
2046 01 23 000000 12 59 34.7 -23 34 05 0.020 0.987 99.2 79.7 14.5 25.85 354.3 N/A N/A
2046 01 24 000000 12 55 56.1 -14 48 28 0.023 0.990 104.7 74.0 14.7 18.59 354.5 N/A N/A
2046 01 25 000000 12 53 27.3 -08 27 30 0.027 0.993 108.9 69.6 14.9 13.62 354.5 N/A N/A
2046 01 26 000000 12 51 37.6 -03 44 50 0.031 0.997 112.2 66.2 15.1 10.26 354.4 N/A N/A
