Passage of 2004 XP14 on July 3rd, 2006 at about 440.000 Km distance

During the passage we captured 2500 single CCDs. This covering the time from 20:27:48 - 21:56:39 UT. The PC clock had been synchronised every 60 seconds with german ptbtime. The camera (SXV-H9) was set to 3x3 binning achiving 2.7"/pixel. Telescope was 35cm f/4.1 Newton. The resulting astrometrical precision was chi=0.09 to 0.50. Except two observations (exceeding chi=1) where the object passed closed to a fairly bright star.

XP14

The close encounter of 2004 XP14 had been observed for several hours. At the begin, right after sunset the object still was moving at 80"/min. The evening sky at our location was still bright as the sun was only at -8 degree altitude. Because of the very bad S/N a single CCD was not sufficient for astrometry.
With stacking (using Astrometrica) the measurement was quite reliable.

Addition of 100 CCDs each 1sec exposure.

The same data stacked with Astrometrica.

An hour later the object moved already as slow as 15"/min. Making capturing quite easy. This series of 132 CCDs (each 0.5sec) covers comparable 3:30 minutes as the series above.

Stacking of 132 CCDs at 0.5sec each.

The last 500 CCDs of the entire series stacked with Astrometrica.