The green dots are objects with absolute magnitude H>22.0* that are known to be in Earth's neighborhood today, shown with EasySky's ecliptic grid set at ten lunar distances. *Greater H = dimmer = smaller for a given reflectivity, usually assumed. See a chart for equivalent size ranges.

Since A/CC last reported on December 8th about successes in observing the smallest near-Earth asteroids, the Moon has been at its brightest and only a few nearby faint objects have been tracked. Of objects with absolute magnitude (H) greater than 22.0, Daily Orbit Update MPECs through this morning have reported 2003 XH10 observations from Great Shefford Observatory late on the 7th and Powell Observatory the next morning, 2003 WY87 from Desert Moon Observatory the morning of the 10th, and 2003 WQ21 from Siding Spring Observatory on the 8th.

A bit bigger (H=21.1) and favorably positioned, 2003 WY25 was reported observed during 7-12 December in 12 sessions by 11 observatories. It is shown circled in the illustration at right, along with the three smaller objects, and was at 9.7 lunar distances from Earth on Thursday. 2003 WY25 was posted by JPL on November 22nd with impact solutions that were eliminated in two days.

Peter Birtwhistle has posted pages telling about Great Shefford's confirmation work on 2003 XJ7 and 2003 XH10 during a busy time for watching fast-moving faint objects passing near Earth.

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Risk monitoring 13 Dec.

The Saturday Daily Orbit Update MPEC (DOU) carries a December 7th observation from Siding Spring Observatory in Australia that extended the observing arc for 2003 XM by eight hours and 51 minutes, and also has a set of positions from La Palma in the Canary Islands from yesterday morning that more than doubles the length of that arc by adding 4.43 days. Today NEODyS slightly lowered its risk assessment and cut its count of impact solutions for 2003 XM. Update: At 9pm in Pasadena, JPL hadn't updated its 2003 XM assessment.

The DOU reports revised measurements for the last four positions reported for 1994 WR12 [link|alt] in December 1994, and for the first five positions reported for 2002 RC117 [link|alt] in Summer 2002. Both objects are small and considered lost. WR12 has impact solutions listed by JPL and NEODyS, but RC117 was listed only briefly.

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