In a seven-day summary of discovering and tracking the smallest near-Earth asteroids, the latest news comes in today's MPEC 2003-Y83, which announces 2003 YH111, an object roughly estimated at 40 meters/yards wide (H=24.5) that was discovered by LINEAR early yesterday in New Mexico and was followed up today by observations from Desert Eagle Observatory in Arizona spanning 3.76 hours, from Great Shefford Observatory in England spanning 14.41 hours, and from Moriyama Observatory in Japan spanning 5.51 hours, plus Sabino Canyon, Table Mountain, New Mexico Skies, and Camarillo observatories in the western U.S., and Linz and Ondrejov observatories in Europe. The MPEC has this object's closest approach at a bit more than three lunar distances early on December 30th.

Alan Harris told the Minor Planet Mailing List (MPML) today that most asteroids of this size rotate faster than once an hour, but "maybe 10-20% . . . have periods of a day or longer. This appears to be one of those less common slow rotators. I hope folks will go for lightcurves tonight."

Since the previous Major News seven-day report on small objects, four others with H>22.0 have been announced, all discovered by LINEAR, including three found early on the 22nd: 2003 YS70 (H=29.2) was announced on the 24th and posted that day with impact solutions. See daily "Risk monitoring" reports from the 24th forward for details. 2003 YT70 (H=25.8, MPEC 2003-Y62) was announced on the 24th with confirmation that morning from Powell and Siding Spring observatories and KLENOT. It was also reported by Desert Moon Observatory from the 27th. 2003 YP94 (H=23.9) was announced in MPEC 2003-Y72 on December 25th as confirmed that morning by LINEAR, which had discovered it on the 22nd. It has been reported since by Pla D'Arguines Observatory from the 26th and from the 27th by Desert Moon and Mt. John observatories.

One other LINEAR discovery is 2003 YN107 (H=26.7, MPEC 2003-Y76), found on the 20th and announced on the 26th after confirmation by Powell Observatory on the 21st and 24th, and by Tenagra II and Siding Spring observatories on the 25th. But it hasn't been reported since.

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Another five small objects with absolute magnitude (brightness) greater than 22 also had recent observations reported this last week: 2003 SH84 (H=23.1) was reported by the Spacewatch 1.8m telescope from the 21st, 2003 WH166 (H=22.2) by LINEAR from the 21st and Desert Moon from the 27th, 2003 WY153 (H=24.4) by Siding Spring from the 15th and 16th, 2003 XZ12 (H=24.4) by Siding Spring from the 25th, 2003 YN1 (H=24.9) by Desert Moon from the 27th, 2003 YQ1 (H=22.1) by LINEAR from the 22nd and by KLENOT and Desert Moon from the 24th, 2003 YR1 (H=22.2) by Great Shefford from the 21st and Powell from the 21st and 24th, and, finally, 2003 YW1 (H=22.8) by LINEAR from the 22nd and the Spacewatch 1.8m telescope from the 25th.

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Meteor news:  The Calcutta Telegraph has a news wrap today carrying a Press Trust of India report that, "Three months after a meteor shot across the sky in Orissa's coastal belt, fragments of its debris are still being recovered in Kendrapara district. . .  So far, 10 fragments have been found from villages and paddy fields." Residents have been warned that keeping fragments is a "penal offence."

Precovery:  MPEC 2003-Y82 today reports that Giussepi Forti has located 2003 SA224 in plate scans from the Mt. Palomar 1.2m Oschin telescope from 20 September and 24 October 1990. This object, with a width roughly estimated at 1.64 km. (1.02 miles), was discovered by LINEAR on September 30th and announced on October 3rd, when it was also posted by JPL with impact solutions. NEODyS posted it the next day, and both risk monitors removed their last solutions on October 11th.

Recovery:  Asteroid 2001 BE10 is a potentially hazardous object discovered by LINEAR on 18 January 2001 and roughly estimated at a half-kilometer in width. It will come to 23-plus lunar distances of Earth in January, when it is a scheduled radar target at Arecibo, which requests help with astrometry. BE10 hadn't been reported seen since 13 April 2001 and Reiner Stoss tells A/CC that he suggested it for observation at the Observatorio Astronomico de Mallorca (OAM), but the facility was busy with upgrading telescopes. So he proposed it to Erich Meyer at Linz Observatory in Austria, where this object was caught early on December 24th. When weather put Linz observations in doubt the next night, Stoss with OAM staffers Salvador Sanchez and Jaime Nomen used the OAM remote-controlled telescope, and the r/c telescope at Nomen's own at Ametlla de Mar Observatory in Spain, to also observe, thus catching 2001 BE10 from three locations early on the 25th and resulting in recovery MPEC 2003-Y69 that same day.

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Risk monitoring 28 Dec.

The Sunday Daily Orbit Update MPEC (DOU) carries observations of 2003 YD45 from Consell Observatory last night in Spain, and today the JPL and NEODyS YD45 risk assessments converged on two impact solutions for 26 November 2074 for this quarter-kilometer object. The DOU also has positions reported for 2003 YS70 from San Marcello Pistoiese Observatory from Friday night in Italy. This didn't add to the length of the observing arc, but today JPL and NEODyS slightly raised their very low risk assessments for this tiny object.

Missing from the DOU are 2003 YE45 and 2003 YT1. Yesterday A/CC originally reported that there were "about two days of visibility left for the two-kilometer 2003 YT1," a misreading of the European Spaceguard Central Node Priority Page's notation that this object will be visible until December 29th of 2004. Thanks to reader Takis Kourouniotis for catching and reporting this mistake.

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