THE ASTRONOMER Electronic Circular No 2489 2008 Oct 07 06.48UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke,
Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074
INTERNET: GUY@TAHQ.DEMON.CO.UK Backup: gmh@wdcc1.bnsc.rl.ac.uk
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 2008 TC_3
Peter Birtwhistle, Great Shefford initially drew our attention on  October 6 to a NEOCP object 8TA9D69 on what appeared to be an almost  certain collision course with Earth (estimated initially at 02:52 UT), probably somewhere over southern Europe/India potentially. He has subsequently imaged the object for which details are awaited.
Images of the object were alo obtained on October 6 at 20h26m, 20h32m,  20h39mUT and submitted to us by Giovanni Sostero, V Gonano, Ernesto Guido and P. Camilleri. These were obtained with a 0.45-m f4.4 reflector  + IMG-1001E as the median of 20 unfiltered exposures of 10 seconds each. At the time the object was about 0.00113AU (about 170,000km).

Dan Green, Central Bureau for Astronomical Telegrams also reports on IAU Circular 8990 that a small asteroidal object (absolute magnitude H = 30.4, suggesting a few metres in size) discovered by the Mt. Lemmon Survey (observer R. A. Kowalski) on Oct. 6.28 UT at Delta = 0.0033 AU (about 1.27 the moon's distance from the earth) will enter the earth's atmosphere over northern Sudan (according to S. Chesley, Jet Propulsion  Laboratory) around Oct. 7.115, moving west to east. Prior to entering  the atmosphere, it may be around visual mag 11. Astrometry, orbital elements, and ephemerides are given on MPECs 2008-T50, 2008-T51, and  2008-T52.
 
Mark Kidger (Herschel Science Centre, European Space Agency European Space Astronomy Centre reports: Spanish observers from the "Observadores_Cometas" Group reported 196 observations of 2008 TC3 during its approach to Earth on the night of 2008 October 6/7. The data were taken by Ramón Naves & Montse Campàs  (MPC 213, Barcelona), Gustavo Muler (MPC J47, Lanzarote), Juan Antonio Henríquez (MPC J51, Tenerife) and Rafael Benavides (MPC J53, Cordoba) between 20:22 and 01:23UT.

The asteroid brightened from R=16.7 approximately at 20:22UT to R=15.5 at 22:50UT before initiating a more rapid rate of brightening. At 00:46 a brightest magnitude of R=13.6 was measured. The last few data points show some rapid irregular fluctuations in brightness due to difficulties in measuring such a fast-moving object.
 
A continuously updated light curve is available at: http://www.astrosurf.com/comets/neos/2008tc3/2008_tc3.htm
 
Guy M Hurst