Possible locations of 2007 WD5 relative to Mars on 30 Jan. 
2008. This NASA/JPL illustration is from Dec. 21st.

According to the NASA/JPL NEO Program Office yesterday, "Pre-discovery observations of asteroid 2007 WD5, taken on November 8, 2007 [and found by Andy Puckett in the Sloan Digital Sky Survey archive] have allowed its orbit to be refined... The impact probability resulting ... has increased to a surprising 3.9% (about 1 in 25 odds)." See full info, the December 23rd DOU MPEC, and earlier news links, which included this JPL illustration.

Contents  on 29 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 29 December '07

The MPC's NEO Confirmation Page is currently empty

The NEOCP is currently empty. There was one listing noted earlier today.

New MPECs  on 29 December '07

Minor Planet Electronic Circulars

As of last check at 2354 UTC, there have been two MPECs issued today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2007-Y53 - "14:39 UT" - 2007 YV29

<< DOU on 29 Dec. '07 >>  MPEC 2007-Y52 - "07:07 UT" - Daily Orbit Update

Observers  on 29 December '07

Sixteen observing facilities appear in today's MPECs.

CodeObserver / observatory
H55Astronomical Research Obs. (ARO) in Illinois, 9 in MPEC 2007-Y52 -- 2007 YN1, 2007 WY3, 2007 UA2, 2007 TD71, 2007 TB23, 2007 SV2, 2007 SV11, 2007 RF5, 1998 VO
235CAST Obs. in Italy, 1 in MPEC 2007-Y53 -- 2007 YV29
176Consell Obs. in Spain, 2 in MPECs 2007-Y52 & 2007-Y53 -- 2007 YZ, 2007 YV29
595Farra d'Isonzo Obs. in Italy, 1 in MPEC 2007-Y53 -- 2007 YV29
143Gnosca Obs. in Switzerland, 1 in MPEC 2007-Y52 -- 2007 XH16
B15Inastars Obs. in Germany, 8 in MPECs 2007-Y52 & 2007-Y53 -- 2007 YV29, 2007 YH, 2007 YF1, 2007 YB2, 2007 XP3, 2007 WF55, 2007 SV2, 1998 YM4
701Junk Bond Obs. in Arizona, 1 in MPEC 2007-Y52 -- 172718
704LINEAR in New Mexico, 4 in MPECs 2007-Y52 & 2007-Y53 -- 2007 YV29, 2007 YM1, 2005 WJ56, 2003 WM25
J76La Murta Obs. in Spain, 1 in MPEC 2007-Y52 -- 68359
A24New Millennium Obs. in Italy, 15 in MPECs 2007-Y52 & 2007-Y53 -- 2007 YV29, 2007 TG8, 2007 TG15, 2005 XK8, 2005 XD1, 2003 BH84, 99935, 86324, 85804, 21374, 20826, 18736, 170903, 143678, 137084
423North Ryde Obs. in New South Wales, 1 in MPEC 2007-Y52 -- 2005 GG
B49Paus Obs. in Spain, 1 in MPEC 2007-Y52 -- 2007 YF1
691Spacewatch 0.9m telescope in Arizona, 1 in MPEC 2007-Y52 -- 172718
291Spacewatch 1.8m telescope in Arizona, 11 in MPEC 2007-Y52 -- 2007 YN1, 2007 YJ, 2007 YF, 2007 XK11, 2007 XJ16, 2007 XD10, 2007 XB10, 2007 WY3, 2007 WU4, 2006 BG, 2005 LW39
147Suno Obs. in Italy, 2 in MPECs 2007-Y52 & 2007-Y53 -- 2007 YV29, 2007 YB2
198Wildberg Obs. in Germany, 3 in MPEC 2007-Y52 -- 2007 XY9, 2007 VH3, 2004 YG1

Impact Risk Monitoring  on 29 December '07

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2354 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 YV29JPL Sentry19052032-2106223.2e-08-4.13-4.890JPL: "Analysis based on 29 observations spanning .65343 days (2007-Dec-28.44971 to 2007-Dec-29.10314)." Diameter approximately 0.609 km. from mean, weighted H=18.7.
2007 YB2JPL Sentry15532043-209828.4e-09-4.61-4.660JPL: "Analysis based on 52 observations spanning 10.783 days (2007-Dec-18.34552 to 2007-Dec-29.12888)." Diameter approximately 0.778 km. from mean, weighted H=18.2.
2007 XK11JPL Sentry1553210115.8e-08-4.84-4.840JPL: "Analysis based on 58 observations spanning 22.999 days (2007-Dec-06.0886 to 2007-Dec-29.08731)." Diameter approximately 0.470 km. from mean, weighted H=19.3.

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 29 December '07

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

1905Noted that JPL Sentry has posted 2007 YV29 as an impact risk - see above
1553Noted that JPL Sentry has updated its 2007 XK11 risk assessment - see above
Noted that JPL Sentry has updated its 2007 YB2 risk assessment - see above
Noted that NEODyS has removed 2007 YB2 as an impact risk - see above
Grabbed MPEC 2007-Y53 - 2007 YV29 - see above
The NEOCP has become empty
0815Grabbed MPEC 2007-Y52 - Daily Orbit Update - see above