Contents  on 12 August '11


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 12 August '11

The MPC's NEO Confirmation Page is currently empty

The NEOCP is currently empty. There were two listings noted earlier today.

New MPECs  on 12 August '11

Minor Planet Electronic Circulars

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

MPEC 2011-P47 - "13:07 UT" - 2011 OJ45

<< DOU on 12 Aug. '11 >>  MPEC 2011-P46 - "06:04 UT" - Daily Orbit Update

Observers  on 12 August '11

Nine observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 21 in MPECs 2011-P46 & 2011-P47 -- 2011 PX, 2011 PU1, 2011 PU, 2011 PO1, 2011 PE2, 2011 OX4, 2011 OW4, 2011 OV4, 2011 OJ45, 2011 OC18, 2011 OA, 2011 NY, 2011 MX2, 2011 MV1, 2011 MT, 2011 MO4, 2011 MK, 2011 KN9, 2011 JP29, 2011 JA8, 2005 XD1
300Bisei Spaceguard Center in Japan, 1 in MPEC 2011-P46 -- 2011 PO1
B92Chinon Obs. in France, 1 in MPEC 2011-P46 -- 1036
C32Ka-Dar Obs. TAU Station in Russia, 1 in MPEC 2011-P46 -- 4341
844Los Molinos Obs. in Uruguay, 1 in MPEC 2011-P46 -- 2011 EZ78
5682David Tholen's team on Mauna Kea in Hawaii, 1 in MPEC 2011-P47 -- 2011 OJ45
F51Pan-STARRS 1 (PS1) in Hawaii, 8 in MPECs 2011-P46 & 2011-P47 -- 2011 OJ45, 2008 RJ1, 2004 RW164, 2004 JO2, 170903, 163373, 159399, 138155
B38Santa Mama Obs. in Italy, 4 in MPEC 2011-P46 -- 2011 JP29, 68348, 37336, 20086
I15Wishing Star Obs. in Rhode Island, 3 in MPEC 2011-P46 -- 2011 PE2, 2011 JA8, 280136
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 12 August '11

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 risk pages.





Notes for Today's Latest Risk Assessments
2011 PE2JPL Sentry15382027-210358.0e-05-2.80-2.860JPL: "Analysis based on 35 observations spanning 4.0979 days (2011-Aug-08.06387 to 2011-Aug-12.16178)." Diameter approximately 0.084 km. from mean, weighted H=23.0.
NEODyS15382027-207158.96e-05-2.76-2.820NEODyS: "Based on 35 optical observations (of which 0 are rejected as outliers) from 2011-08-08.065 to 2011-08-12.163."
2011 PU1JPL Sentry15382048-2109804.5e-04-3.74-4.050JPL: "Analysis based on 23 observations spanning 4.2760 days (2011-Aug-06.9677 to 2011-Aug-11.243704)." Diameter approximately 0.030 km. from mean, weighted H=25.3.
NEODyS15382048-2090994.41e-04-3.75-3.990NEODyS: "Based on 23 optical observations (of which 0 are rejected as outliers) from 2011-08-06.968 to 2011-08-11.244."

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 12 August '11

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

1903Noted that the NEOCP has become empty
1538Noted that JPL Sentry has updated its 2011 PE2 risk assessment - see above
Noted that NEODyS has updated its 2011 PE2 risk assessment - see above
Noted that JPL Sentry has updated its 2011 PU1 risk assessment - see above
Noted that NEODyS has updated its 2011 PU1 risk assessment - see above
Grabbed MPEC 2011-P46 - Daily Orbit Update - see above
Grabbed MPEC 2011-P47 - 2011 OJ45 - see above
0515Noted that the NEOCP has become active