Contents  on 21 February '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 21 February '08

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

When last checked at 2354 UTC today, the Minor Planet Center's NEO discovery Confirmation Page (NEOCP) had three updated listings. Of these, one was a "one nighter."

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 February '08

Minor Planet Electronic Circulars

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

MPEC 2008-D24 - "17:36 UT" - PHAs

MPEC 2008-D23 - "17:36 UT" - Unusual Minor Planets

MPEC 2008-D22 - "17:36 UT" - Amors

MPEC 2008-D21 - "17:36 UT" - Atens and Apollos

MPEC 2008-D20 - "17:31 UT" - Distant Minor Planets

MPEC 2008-D19 - "17:15 UT" - Observable Comets

<< DOU on 21 Feb. '08 >>  MPEC 2008-D18 - "07:06 UT" - Daily Orbit Update

Observers  on 21 February '08

Two observing facilities appear in today's MPEC.

CodeObserver / observatory
H55Astronomical Research Obs. (ARO) in Illinois, 17 in MPEC 2008-D18 -- 2008 CZ118, 2008 CR118, 2008 CR116, 2008 CM20, 2008 CM116, 2008 CL70, 2008 CL116, 2008 CH70, 2008 CF, 2008 CE6, 2008 CE119, 2008 CC71, 2008 CA119, 2008 BE, 2008 AV28, 2008 AN33, 2008 AG1
J51Atlante Obs. in the Canary Islands, 6 in MPEC 2008-D18 -- 2008 CN1, 153591, 11398, 3691, 1866, 1627

Impact Risk Monitoring  on 21 February '08

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 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 CL116NEODyS1355207827.31e-08-4.81-4.910NEODyS: "Based on 60 optical observations (of which 0 are rejected as outliers) from 2008/02/10.407 to 2008/02/17.074."
JPL Sentry13542078-210251.8e-07-4.45-4.900JPL: "Analysis based on 60 observations spanning 6.6665 days (2008-Feb-10.40671 to 2008-Feb-17.07319)." Diameter approximately 0.294 km. from mean, weighted H=20.3.
2008 CC71NEODyS13552034-2083321.02e-04-4.04-4.200NEODyS: "Based on 32 optical observations (of which 0 are rejected as outliers) from 2008/02/09.397 to 2008/02/19.487."
JPL Sentry13542033-2082261.0e-04-4.04-4.200JPL: "Analysis based on 32 observations spanning 10.090 days (2008-Feb-09.39625 to 2008-Feb-19.48606)." Diameter approximately 0.036 km. from mean, weighted H=24.9.

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 February '08

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

1844Grabbed MPEC 2008-D21 - Atens and Apollos - see above
Grabbed MPEC 2008-D22 - Amors - see above
Grabbed MPEC 2008-D23 - Unusual Minor Planets - see above
Grabbed MPEC 2008-D24 - PHAs - see above
1750Grabbed MPEC 2008-D19 - Observable Comets - see above
Grabbed MPEC 2008-D20 - Distant Minor Planets - see above
1355Noted that NEODyS has updated its 2008 CC71 risk assessment - see above
Noted that NEODyS has updated its 2008 CL116 risk assessment - see above
1354Noted that JPL Sentry has updated its 2008 CC71 risk assessment - see above
Noted that JPL Sentry has updated its 2008 CL116 risk assessment - see above
Grabbed MPEC 2008-D18 - Daily Orbit Update - see above