Contents  on 25 April '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 25 April '11

The MPC's NEO Confirmation Page has 57 listings: 4 new, 53 updated

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had four new and 53 updated listings. Of these, 38 were "one nighters." So far The Tracking News has counted a total of 82 listings on the NEOCP today.

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 25 April '11

Minor Planet Electronic Circulars

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

MPEC 2011-H35 - "23:10 UT" - 2011 HT

MPEC 2011-H34 - "23:05 UT" - 2011 HS

MPEC 2011-H33 - "22:59 UT" - 2011 HR

MPEC 2011-H32 - "22:51 UT" - 2011 HQ

MPEC 2011-H31 - "16:22 UT" - 2011 HP

<< DOU on 25 Apr. '11 >>  MPEC 2011-H30 - "07:06 UT" - Daily Orbit Update

Observers  on 25 April '11

A total of 22 observers appear in today's MPECs.

CodeObserver / observatory
300Bisei Spaceguard Center in Japan, 1 in MPEC 2011-H30 -- 2011 HJ
160Castelmartini Obs. in Italy, 7 in MPEC 2011-H30 -- 2011 EZ78, 2011 AO52, 263976, 188174, 163250, 162463, 137170
703Catalina Sky Survey (CSS) in Arizona, 2 in MPECs 2011-H30 & 2011-H34 -- 2011 HS, 2004 FU4
807|Robert Holmes via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 6 in MPEC 2011-H30 -- 2011 HF, 2011 GP65, 2011 GH62, 2011 FQ29, 2011 CB50, 2011 BO59
113Drebach Obs. in Germany, 1 in MPEC 2011-H30 -- 2011 EZ78
J95Great Shefford Obs. in England, 6 in MPECs 2011-H30, 2011-H31, 2011-H32, 2011-H33, 2011-H34 & 2011-H35 -- 2011 HT, 2011 HS, 2011 HR, 2011 HQ, 2011 HP, 2011 HJ
A17Guidestar Obs. in Germany, 5 in MPECs 2011-H30 & 2011-H32 -- 2011 HQ, 2011 GQ65, 2011 GL62, 2011 FB29, 2011 EZ78
844Los Molinos Obs. in Uruguay, 1 in MPEC 2011-H30 -- 54401
B67Mirasteilas Obs. in Switzerland, 1 in MPEC 2011-H30 -- 24445
118Modra Obs. in Slovakia, 1 in MPEC 2011-H32 -- 2011 HQ
A99Monte Baldo Obs. in Italy, 1 in MPEC 2011-H34 -- 2011 HS
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPECs 2011-H31 & 2011-H35 -- 2011 HT, 2011 HP
A13Naef Obs. in Switzerland, 1 in MPEC 2011-H30 -- 2007 LQ19
A24New Millennium Obs. in Italy, 23 in MPEC 2011-H30 -- 2011 CH71, 2011 AN16, 2008 FT6, 2004 FU4, 2004 FG1, 2002 TD60, 2001 QP181, 89958, 89830, 85953, 53435, 40267, 274138, 252793, 23187, 23183, 141525, 136617, 11885, 5626, 4954, 4401, 3554
F51Pan-STARRS 1 (PS1) in Hawaii, 2 in MPECs 2011-H32 & 2011-H33 -- 2011 HR, 2011 HQ
H06|H. Sato in Japan via RAS Obs. Mayhill in New Mexico, 1 in MPEC 2011-H30 -- 248590
D90`Kevin Hills in England via RAS Obs. Moorook in South Australia, 2 in MPECs 2011-H30 & 2011-H31 -- 2011 HP, 2011 HJ
204Schiaparelli Obs. in Italy, 1 in MPEC 2011-H34 -- 2011 HS
691Spacewatch 0.9m telescope in Arizona, 1 in MPEC 2011-H30 -- 1998 HK49
I93St. Pardon de Conques Obs. in France, 1 in MPEC 2011-H33 -- 2011 HR
926Tenagra II Obs. in Arizona, 1 in MPEC 2011-H33 -- 2011 HR
D96Tzec Maun Obs. Moorook in South Australia, 1 in MPEC 2011-H31 -- 2011 HP
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 25 April '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 (backup) risk pages.





Notes for Today's Latest Risk Assessments
2011 HFJPL Sentry14512030-21101651.2e-06-3.74-4.090JPL: "Analysis based on 19 observations spanning 2.0428 days (2011-Apr-22.16366 to 2011-Apr-24.20649)." Diameter approximately 0.261 km. from mean, weighted H=20.6.
NEODyS14512030-2088207.43e-07-3.88-4.160NEODyS: "Based on 19 optical observations (of which 0 are rejected as outliers) from 2011-04-22.164 to 2011-04-24.207."

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 25 April '11

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

2359Grabbed MPEC 2011-H34 - 2011 HS - see above
Grabbed MPEC 2011-H35 - 2011 HT - see above
2303Grabbed MPEC 2011-H32 - 2011 HQ - see above
Grabbed MPEC 2011-H33 - 2011 HR - see above
1633Grabbed MPEC 2011-H31 - 2011 HP - see above
1451Noted that JPL Sentry has updated its 2011 HF risk assessment - see above
Noted that NEODyS has updated its 2011 HF risk assessment - see above
Grabbed MPEC 2011-H30 - Daily Orbit Update - see above