Contents  on 21 December '07


The latest A/CC news is available via framed access, RSS news feed RSS news feed, or redirection. - Note: A/CC has a main Web site and also a backup site with its own duplicate RSS news feed.

Navigation tips: Use the << and >> arrows on the menus for each regular section (Observers, Risks, etc.) to move to the previous and next day's news for that section. Use the Index menu item to access specific days this year through a calendar interface. And use the all-up news archive to access news from any time since A/CC began in early 2002. To keep track of what's new each day, watch the Chronology section.

NEOCP Activity  on 21 December '07

The MPC's NEO Confirmation Page has 2 listings: 1 new, 1 updated

When last checked at 2353 UTC today, the Minor Planet Center's NEO discovery Confirmation Page (NEOCP) had one new and one updated listing. Both of these were "one nighters." So far The Tracking News has counted a total of six objects listed on the NEOCP at some point today.

To learn how observers use the NEOCP, see the Practical guide on how to observe NEOCP object by Birtwhistle et al. at Suno Observatory.

New MPECs  on 21 December '07

Minor Planet Electronic Circulars

As of last check at 2353 UTC, there has been one MPEC issued today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

<< DOU on 21 Dec. '07 >>  MPEC 2007-Y40 - "07:06 UT" - Daily Orbit Update

Observers  on 21 December '07

A total of 22 observing facilities appear in today's MPEC.

CodeObserver / observatory
H55Astronomical Research Obs. (ARO) in Illinois, 4 in MPEC 2007-Y40 -- 2007 YK, 2007 YF1, 2007 XV23, 2007 XQ3
A81Balzaretto Obs. in Italy, 1 in MPEC 2007-Y40 -- 2003 BH84
A74Bergen-Enkheim Obs. in Germany, 1 in MPEC 2007-Y40 -- 2004 XM14
621Bergisch Gladbach Obs. in Germany, 1 in MPEC 2007-Y40 -- 2007 YN1
703Catalina Sky Survey (CSS) in Arizona, 4 in MPEC 2007-Y40 -- 66407, 172974, 7092, 1685
106Crni Vrh Obs. in Slovenia, 1 in MPEC 2007-Y40 -- 99935
448Desert Moon Obs. in New Mexico, 5 in MPEC 2007-Y40 -- 2007 VH3, 2007 UW3, 2007 EX, 2003 DC14, 152942
595Farra d'Isonzo Obs. in Italy, 1 in MPEC 2007-Y40 -- 136793
A17Guidestar Obs. in Germany, 1 in MPEC 2007-Y40 -- 140288
246KLENOT in the Czech Republic, 5 in MPEC 2007-Y40 -- 2007 YZ, 2007 YK, 2007 YF1, 2007 YB2, 2007 XH16
704LINEAR in New Mexico, 2 in MPEC 2007-Y40 -- 2005 WJ56, 4450
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPEC 2007-Y40 -- 1998 YM4, 35107
A24New Millennium Obs. in Italy, 8 in MPEC 2007-Y40 -- 2007 WF55, 2007 TG15, 2005 XD1, 2003 BH84, 1993 TQ2, 85804, 21374, 18736
H45Petit Jean Mtn. South Obs. in Arkansas, 1 in MPEC 2007-Y40 -- 172974
461SZTE Asteroid Program in Hungary, 1 in MPEC 2007-Y40 -- 171819
204Schiaparelli Obs. in Italy, 1 in MPEC 2007-Y40 -- 2007 XH16
691Spacewatch 0.9m telescope in Arizona, 11 in MPEC 2007-Y40 -- 2007 YG, 2007 XP3, 2007 XD10, 2003 XF11, 2003 WL25, 2003 AJ73, 2002 TC70, 1991 JW, 172718, 172678, 143404
291Spacewatch 1.8m telescope in Arizona, 8 in MPEC 2007-Y40 -- 2007 YN1, 2007 YB2, 2007 XJ16, 2007 XD10, 2006 WR1, 2005 RC, 2000 CL33, 1999 RQ28
6735Jim Young via Table Mtn. Obs. in southern California, 2 in MPEC 2007-Y40 -- 2007 YM1, 2007 YB2
F85Tiki Obs. in Tahiti, 1 in MPEC 2007-Y40 -- 2007 XH16
A48Verona Obs. in Italy, 3 in MPEC 2007-Y40 -- 2007 XH16, 2007 WF55, 2005 XD1
198Wildberg Obs. in Germany, 2 in MPEC 2007-Y40 -- 2007 YB2, 2004 AR1

Impact Risk Monitoring  on 21 December '07

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2353 UTC)
See the CRT page for a list of all objects rated recently as risks.
Note that the time horizon for JPL is 100 years from today and for NEODyS is now usually the year 2090.
For the latest official risk assessments, and for explanations of the terminology, see the JPL NEO Program Sentry and NEODyS CLOMON (backup) risk pages.





Notes for Today's Latest Risk Assessments
2007 YB2NEODyS13552030-205792.9e-08-4.02-4.390NEODyS: "Based on 38 optical observations (of which 0 are rejected as outliers) from 2007/12/18.346 to 2007/12/21.079."
JPL Sentry13542029-2106318.2e-08-3.65-4.310JPL: "Analysis based on 38 observations spanning 2.7326 days (2007-Dec-18.34552 to 2007-Dec-21.07811)." Diameter approximately 0.816 km. from mean, weighted H=18.1.

Legend: VI# = VI count, Prob Cum = cumulative probability, PS Cum/Max = cumulative/maximum Palermo Scale, TS = Torino Scale

An impact solution, also known as a "virtual impactor" (VI), is not a prediction but rather a possibility derived from a variant orbit calculation that cannot be eliminated yet based on the existing data. Elimination can come quickly with just a little further observation or may take weeks or months, sometimes years. Once superceded or eliminated, a former impact solution has zero relevance to an object's risk. See Jon Giorgini's "Understanding Risk Pages" to learn more.

Chronology  on 21 December '07

Times are UTC for when items were noted or added by The Tracking News.

1355Noted that NEODyS has updated its 2007 YB2 risk assessment - see above
Grabbed MPEC 2007-Y40 - Daily Orbit Update - see above
1354Noted that JPL Sentry has updated its 2007 YB2 risk assessment - see above