2007's Close Approach of (2340) Hathor

2007's Close Approach of (2340) Hathor


In early November 2007, the minor planet (2340) Hathor made a close approach to the earth. Of the many earth-approachers that have been found over the years, I still clearly remember the excitement of this object's discovery in 1976 when it passed within 0.00775 A.U. of the earth on October 20. By the time of the 2007 return, (2340) Hathor has completed almost exactly 40 revolutions and the earth has completed almost exactly 31 revolutions, so the circumstances of this year's encounter are similar.

On the evening of November 2, the object was bright and close to the meridian at the end of evening twilight, so I shot 24 consecutive exposures of 60 seconds duration between 3:00 UTC and 3:30 UTC. I submitted the following astrometry to the Minor Planet Center by stacking four frames with six exposures each:

02340         C2007 11 03.12999 22 37 50.04 -11 29 57.9          17.4 R      H06
02340         C2007 11 03.13476 22 37 52.46 -11 29 52.6          17.8 R      H06
02340         C2007 11 03.13954 22 37 54.86 -11 29 46.7          17.3 R      H06
02340         C2007 11 03.14431 22 37 57.32 -11 29 40.8          18.1 R      H06
The following animation is a restack of the 24 individual frames into eight frames of three exposures each. At the time, the object was 0.1186 A.U. from the earth and moving at 5.23"/minute.

The exposures were taken remotely at the RAS Observatory in Mayhill, New Mexico, with the GRAS-004 0.25-m f/3.4 Takahashi Epsilon E250 Astrograph.