Sunday 8 August 2010

2010 July notes

July was very disappointing with only 21 hours observing, spread over 10 rather poor nights, my worst monthly figures since June 2007 and my worst July since the observatory started operating in May 2002. The best of the skies were at the beginning of the month.

Early on 4th July the 1.5-m scope on Mt. Lemmon picked up Apollo 2010 NG, over 15 Lunar distances (LD) from Earth, but due to pass at just under 6 LD on July 13. Although probably only about 30 meters in diameter it was predicted to reach mag. 17 as it plunged far south in the days leading up to its close approach. I caught it on the nights of July 4, 6 and 9 before it went out of view, the last night it was moving rapidly south, at a declination of -25 and only 10 degrees above the horizon.

One other object which was followed for three consecutive nights in early July was 2010 NB, a 19th mag LINEAR discovery from July 1. By July 3.0 when I first observed it, it was moving north, at a high northern declination and fading fast - it had evaded discovery during the last week of June when it was at its closest and was already a magnitude fainter when LINEAR picked it up. It was last detected by the Astronomical Research Observatory, Westfield, USA on July 6.2 at magnitude +21.4.