Contents  on 23 December '08


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 23 December '08

The MPC's NEO Confirmation Page has 3 listings: 3 updated

When last checked at 2300 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had three updated listings. Of these, two 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 23 December '08

Minor Planet Electronic Circulars

As of last check at 2300 UTC, there have been five MPECs issued today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2008-Y48 - "12:10 UT" - 2008 YJ3

<< DOU on 23 Dec. '08 >>  MPEC 2008-Y47 - "07:06 UT" - Daily Orbit Update

No observations of objects are reported.

MPEC 2008-Y46 - "04:48 UT" - 2008 CL1

MPEC 2008-Y45 - "04:42 UT" - 2005 SG19

MPEC 2008-Y44 - "00:40 UT" - 2005 CS6

Observers  on 23 December '08

Five observing facilities appear in today's MPECs.

CodeObserver / observatory
493Calar Alto Obs. in Spain, 4 in MPECs 2008-Y44, 2008-Y45, 2008-Y46 & 2008-Y48 -- 2008 YJ3, 2008 CL1, 2005 SG19, 2005 CS6
474Mt. John Obs. in New Zealand, 1 in MPEC 2008-Y48 -- 2008 YJ3
854Sabino Canyon Obs. in Arizona, 1 in MPEC 2008-Y48 -- 2008 YJ3
B04Saint-Barthelemy Obs. in Italy, 1 in MPEC 2008-Y48 -- 2008 YJ3
291Spacewatch 1.8m telescope in Arizona, 1 in MPEC 2008-Y48 -- 2008 YJ3
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 23 December '08

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2300 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.
Note that the time horizon for JPL is 100 years from today and for NEODyS is 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
2008 YJ3JPL Sentry14592027-2108982.7e-07-3.96-4.930JPL: "Analysis based on 21 observations spanning 1.2072 days (2008-Dec-22.26734 to 2008-Dec-23.47454)." Diameter approximately 0.328 km. from mean, weighted H=20.1.
2008 YD3NEODyS1459202214.9e-10-9.27-9.270NEODyS: "Based on 12 optical observations (of which 0 are rejected as outliers) from 2008/12/22.343 to 2008/12/22.486."
2008 YC3NEODyS14592053-2090563.34e-04-3.78-4.010NEODyS: "Based on 13 optical observations (of which 1 are rejected as outliers) from 2008/12/22.254 to 2008/12/22.757."
2008 YO2NEODyS14592052-2089112.2e-06-5.75-5.910NEODyS: "Based on 25 optical observations (of which 0 are rejected as outliers) from 2008/12/21.166 to 2008/12/22.168."

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 23 December '08

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

1459Noted that NEODyS has posted 2008 YC3 as an impact risk - see above
Noted that NEODyS has posted 2008 YD3 as an impact risk - see above
Noted that JPL Sentry has posted 2008 YJ3 as an impact risk - see above
Noted that NEODyS has posted 2008 YO2 as an impact risk - see above
Grabbed MPEC 2008-Y47 - Daily Orbit Update - see above
Grabbed MPEC 2008-Y48 - 2008 YJ3 - see above
0517Grabbed MPEC 2008-Y45 - 2005 SG19 - see above
Grabbed MPEC 2008-Y46 - 2008 CL1 - see above
0046Grabbed MPEC 2008-Y44 - 2005 CS6 - see above