Piece of the Mifflin Meteorite. 
Credit: Jeff Miller, UW-M.

Last month the University of Wisconsin at Madison reported that pieces of the Mifflin Meteorite have been added to its Geology Museum collection of meteorites from around the state and elsewhere. Mifflin Township is where fragments were found after a spectacular atmospheric event in the evening of April 14th this year (news, video). Photo by Jeff Miller, courtesy of UW-M.

Contents  on 21 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 21 December '10

The MPC's NEO Confirmation Page has 1 listing: 1 new

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had one new listing.

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 21 December '10

Minor Planet Electronic Circulars

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

<< DOU on 21 Dec. '10 >>  MPEC 2010-Y20 - "07:11 UT" - Daily Orbit Update

Observers  on 21 December '10

Eight observers appear in today's MPEC.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 9 in MPEC 2010-Y20 -- 2010 XZ58, 2010 XR45, 2010 XC25, 2010 WZ8, 2010 WD9, 2010 TP55, 2010 TK54, 2010 MS1, 2010 CO44
J51Atlante Obs. in the Canary Islands, 1 in MPEC 2010-Y20 -- 2010 JL33
160Castelmartini Obs. in Italy, 2 in MPEC 2010-Y20 -- 2010 XC15, 2010 JL33
703Catalina Sky Survey in Arizona, 1 in MPEC 2010-Y20 -- 2008 VK14
379Hamamatsu-Yuto Obs. in Japan, 2 in MPEC 2010-Y20 -- 2010 JL33, 2006 VB14
H75Indian Hill North Obs. in Ohio, 1 in MPEC 2010-Y20 -- 2003 UV11
118Modra Obs. in Slovakia, 2 in MPEC 2010-Y20 -- 2010 RR179, 2010 JL33
E12Siding Spring Survey in New South Wales, 1 in MPEC 2010-Y20 -- 2010 VX139
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 21 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 XC25JPL Sentry17222024-2104199.6e-06-2.86-3.150JPL: "Analysis based on 50 observations spanning 11.039 days (2010-Dec-08.37716 to 2010-Dec-19.416032)." Diameter approximately 0.257 km. from mean, weighted H=20.6.
NEODyS17222043-2090181.3e-05-2.71-3.040NEODyS: "Based on 50 optical observations (of which 1 are rejected as outliers) from 2010-12-08.378 to 2010-12-19.417."

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 '10

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

1722Noted that JPL Sentry has updated its 2010 XC25 risk assessment - see above
Noted that NEODyS has updated its 2010 XC25 risk assessment - see above
Grabbed MPEC 2010-Y20 - Daily Orbit Update - see above