Contents  on 13 September '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 13 September '11

The MPC's NEO Confirmation Page has 2 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had two objects listed. Of these, one was a "one nighter."

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 13 September '11

Minor Planet Electronic Circulars

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

MPEC 2011-R48 - "20:05 UT" - 2009 TK12

MPEC 2011-R47 - "17:36 UT" - PHAs

MPEC 2011-R46 - "17:36 UT" - Unusual Minor Planets

MPEC 2011-R45 - "17:36 UT" - Amors

MPEC 2011-R44 - "17:36 UT" - Atens and Apollos

MPEC 2011-R43 - "17:32 UT" - Observable Comets

<< DOU on 13 Sept. '11 >>  MPEC 2011-R42 - "06:10 UT" - Daily Orbit Update

Observers  on 13 September '11

Nine observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 23 in MPEC 2011-R42 -- 2011 RR12, 2011 RF, 2011 QS49, 2011 QS2, 2011 QG9, 2011 QF23, 2011 QE14, 2011 PS, 2011 OY17, 2011 OV4, 2011 OM5, 2011 KN9, 2011 JA8, 2011 HC36, 2009 WR6, 2009 QZ6, 2008 SR7, 2004 QV16, 2004 PX27, 247517, 142348, 101955, 4503
J51Atlante Obs. in the Canary Islands, 2 in MPEC 2011-R42 -- 138524, 1036
160Castelmartini Obs. in Italy, 3 in MPEC 2011-R42 -- 2011 QF23, 2011 LJ19, 2011 HD63
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 2 in MPEC 2011-R42 -- 2011 LA19, 2007 YZ
5682David Tholen's team on Mauna Kea in Hawaii, 2 in MPECs 2011-R42 & 2011-R48 -- 2011 PU1, 2009 TK12
B67Mirasteilas Obs. in Switzerland, 2 in MPEC 2011-R42 -- 138524, 7341
645Sloan Digital Sky Survey (SDSS) in New Mexico, 5 in MPEC 2011-R42 -- 11500, 4450, 4179, 3200, 2201
A48Verona Obs. in Italy, 1 in MPEC 2011-R42 -- 2011 LJ19
I15Wishing Star Obs. in Rhode Island, 3 in MPEC 2011-R42 -- 2004 JO2, 37336, 275545
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 13 September '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 PU1JPL Sentry16222061-2102694.0e-04-3.71-4.110JPL: "Analysis based on 48 observations spanning 26.251 days (2011-Aug-06.9677 to 2011-Sep-02.21851)." Diameter approximately 0.033 km. from mean, weighted H=25.1.
NEODyS16222061-20901145.44e-04-3.57-3.950NEODyS: "Based on 48 optical observations (of which 1 are rejected as outliers) from 2011-08-06.968 to 2011-09-02.219."
2008 EM68JPL Sentry04012012-21109661.5e-05-5.30-5.750JPL: "Analysis based on 12 observations spanning .11019 days (2008-Mar-08.25164 to 2008-Mar-08.36183)." Diameter approximately 0.010 km. from mean, weighted H=27.7.

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 13 September '11

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

2015Grabbed MPEC 2011-R48 - 2009 TK12 - see above
1907Grabbed MPEC 2011-R43 - Observable Comets - see above
Grabbed MPEC 2011-R44 - Atens and Apollos - see above
Grabbed MPEC 2011-R45 - Amors - see above
Grabbed MPEC 2011-R46 - Unusual Minor Planets - see above
Grabbed MPEC 2011-R47 - PHAs - see above
1622Noted 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-R42 - Daily Orbit Update - see above
0401Noted that JPL Sentry has updated its 2008 EM68 risk assessment - see above