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2007 WV4
was listed as PHA "Potentially Hazardous Asteroid". It was discovered and confirmed by Spacewatch MPEC K07W46 on November 19-21. Follow-up observations came from J95 Great Shefford, H55 ARI Charleston and A17 Guidestar Weinheim. Those observations made it possible to remove it on November 29 from both risk tables of NeoDys and JPL.
The observations at Weinheim where difficult because of moonlight and clouds. During the second set of stacked images clouds limited the exposure to only 5 minutes. Noticable by the shorter streaks of the stars. Surprisingly it was still good visible and with a SNR of well above 6 also measurable. Exposures where interrupted for 50 minutes and a slow moving cloud field demanded a lot of patience from the observer to achieve the third measurement.
Its diameter is thought to be about 500 meters.
Stacks no. 1+3 of 600 sec. Stack no. 2 of 300 sec., 14 inch Schmidt-Cassegrain, ST8-XME 2x2 binned,
image scale 1.75"/pixel, image center 04h03m35s, +23°16'32"