A remnant of impacting asteroid 2008 TC3, found at 
Almahata Sitta, Sudan. Photo courtesy NASA/SETI.

The Carnegie Institution of Washington reports that it appears the parent body from which 2008 TC3 orginated was "heated to the point of melting and then cooled into crystals so quickly that the oxygen isotopes present could not come to an equilibrium distribution throughout." This photo, courtesy of NASA/SETI, shows one fragment (of hundreds) in place where found in Sudan. See more pictures and info here, NASA has a news item, and "Fire in the Nubian Sky" is a good read.

Contents  on 16 December '10


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 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 16 December '10

The MPC's NEO Confirmation Page has 11 listings: 1 new, 10 updated

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had one new and ten updated listings. Of these, five were "one nighters." So far The Tracking News has counted a total of nineteen listings on the NEOCP at some point today.

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

New MPECs  on 16 December '10

Minor Planet Electronic Circulars

As of last check at 2359 UTC, there have been eight MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2010-Y08 - "16:40 UT" - 2010 XR69

MPEC 2010-Y07 - "16:33 UT" - 2010 XQ69

MPEC 2010-Y06 - "16:14 UT" - 2010 XP69

<< DOU on 16 Dec. '10 >>  MPEC 2010-Y05 - "07:09 UT" - Daily Orbit Update

MPEC 2010-Y04 - "06:13 UT" - 2010 XO69

MPEC 2010-Y03 - "06:02 UT" - 2010 XN69

MPEC 2010-Y02 - "05:16 UT" - 2010 XM69

MPEC 2010-Y01 - "04:55 UT" - 2010 XL69

Observers  on 16 December '10

Seventeen observers appear in today's MPECs.

CodeObserver / observatory
B17AZT-8 Evpatoria in the Ukraine, 1 in MPEC 2010-Y05 -- 2003 MJ4
H21Astronomical Research Obs. Westfield in Illinois, 24 in MPECs 2010-Y02 & 2010-Y05 -- 2010 XZ58, 2010 XV58, 2010 XO10, 2010 XN56, 2010 XN25, 2010 XM69, 2010 XL56, 2010 XK52, 2010 XG3, 2010 XG25, 2010 XG11, 2010 XD25, 2010 XC24, 2010 XC15, 2010 XB25, 2010 XA25, 2010 WR7, 2010 WQ7, 2010 WL, 2010 WG3, 2010 VY139, 2010 VS21, 2010 VB140, 2010 LR68
160Castelmartini Obs. in Italy, 1 in MPEC 2010-Y05 -- 2010 JL33
703Catalina Sky Survey (CSS) in Arizona, 8 in MPECs 2010-Y02 & 2010-Y05 -- 2010 XM69, 2010 WZ8, 2010 VY190, 2010 TC47, 2004 YZ23, 68278, 40267, 141498
I114Joseph Masiero in southern California via Gemini South Obs. in Chile, 1 in MPEC 2010-Y06 -- 2010 XP69
379Hamamatsu-Yuto Obs. in Japan, 4 in MPEC 2010-Y05 -- 2010 JL33, 2006 VB14, 2005 GC120, 2000 AC6
J28Jaen Obs. in Spain, 1 in MPEC 2010-Y05 -- 2010 TM3
704LINEAR in New Mexico, 5 in MPECs 2010-Y05 & 2010-Y08 -- 2010 XR69, 2006 WY2, 23183, 11405, 5869
J75La Sagra Obs. in Spain, 2 in MPEC 2010-Y05 -- 152931, 1864
B33Libbiano Obs. in Italy, 1 in MPEC 2010-Y01 -- 2010 XL69
H01Magdalena Ridge Obs. (MRO) in New Mexico, 2 in MPECs 2010-Y02 & 2010-Y07 -- 2010 XQ69, 2010 XM69
5682David Tholen's team on Mauna Kea in Hawaii, 3 in MPEC 2010-Y05 -- 2010 OL101, 2010 OF101, 2010 MR
G96Mt. Lemmon Survey (MLS) in Arizona, 13 in MPECs 2010-Y01, 2010-Y02, 2010-Y03, 2010-Y04, 2010-Y05, 2010-Y07 & 2010-Y08 -- 2010 XT51, 2010 XR69, 2010 XQ69, 2010 XO69, 2010 XN69, 2010 XM69, 2010 XL69, 2010 XB24, 2010 JF88, 2004 QT24, 1999 XR35, 252399, 210012
583Odessa-Mayaki Obs. in the Ukraine, 1 in MPEC 2010-Y05 -- 2010 JL33
691Spacewatch 0.9m telescope in Arizona, 9 in MPECs 2010-Y02 & 2010-Y05 -- 2010 XO56, 2010 XM69, 2010 XE25, 2010 XC25, 2010 VX39, 2002 RB126, 2002 KL3, 1999 XR35, 1999 PJ1
291Spacewatch 1.8m telescope in Arizona, 1 in MPEC 2010-Y05 -- 2010 XT51
C51WISE in Earth polar orbit, 1 in MPEC 2010-Y06 -- 2010 XP69
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 16 December '10

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2359 UTC)
See the CRT page for a list of all objects rated recently as risks and our ephemerides page for a list of risk-listed objects under current observation.
The time horizon for JPL is 100 years from today and for NEODyS is usually the year 2090. Both also post impact solutions beyond 100 years for a few special objects.
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
2010 XQ69JPL Sentry19042071-2108103.7e-08-6.50-6.590JPL: "Analysis based on 20 observations spanning 1.9501 days (2010-Dec-14.24058 to 2010-Dec-16.19073)." Diameter approximately 0.089 km. from mean, weighted H=22.9.
2010 XN69JPL Sentry16242020-21101246.4e-05-4.95-6.140JPL: "Analysis based on 15 observations spanning .89999 days (2010-Dec-15.23581 to 2010-Dec-16.1358)." Diameter approximately 0.018 km. from mean, weighted H=26.3.
NEODyS16242020-2090783.84e-05-5.13-6.20NEODyS: "Based on 15 optical observations (of which 0 are rejected as outliers) from 2010-12-15.237 to 2010-12-16.137."
2010 XC25JPL Sentry16242024-2050132.3e-06-3.14-3.640JPL: "Analysis based on 43 observations spanning 6.9164 days (2010-Dec-08.37716 to 2010-Dec-15.29353)." Diameter approximately 0.265 km. from mean, weighted H=20.6.
NEODyS16242024-2090411.78e-05-2.50-3.130NEODyS: "Based on 43 optical observations (of which 0 are rejected as outliers) from 2010-12-08.378 to 2010-12-15.294."

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 16 December '10

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

1904Noted that JPL Sentry has posted 2010 XQ69 as an impact risk - see above
1800Grabbed MPEC 2010-Y07 - 2010 XQ69 - see above
Grabbed MPEC 2010-Y08 - 2010 XR69 - see above
1624Noted that JPL Sentry has updated its 2010 XC25 risk assessment - see above
Noted that NEODyS has updated its 2010 XC25 risk assessment - see above
Noted that JPL Sentry has posted 2010 XN69 as an impact risk - see above
Noted that NEODyS has posted 2010 XN69 as an impact risk - see above
Grabbed MPEC 2010-Y05 - Daily Orbit Update - see above
Grabbed MPEC 2010-Y06 - 2010 XP69 - see above
0718Grabbed MPEC 2010-Y04 - 2010 XO69 - see above
0609Grabbed MPEC 2010-Y03 - 2010 XN69 - see above
0540Grabbed MPEC 2010-Y02 - 2010 XM69 - see above
0511Grabbed MPEC 2010-Y01 - 2010 XL69 - see above