Contents  on 7 April '11

Resources:

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 7 April '11

The MPC's NEO Confirmation Page has 7 listings: 7 updated

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had seven updated listings. Of these, four were "one nighters." So far The Tracking News has counted a total of sixteen 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 7 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-G56 - "16:36 UT" - 2008 MN1


MPEC 2011-G55 - "10:16 UT" - 2011 GC55


MPEC 2011-G54 - "10:09 UT" - 2011 GB55


MPEC 2011-G53 - "10:02 UT" - 2011 GA55


MPEC 2011-G52 - "09:54 UT" - 2011 GZ54


<< DOU on 7 Apr. '11 >>  MPEC 2011-G51 - "07:10 UT" - Daily Orbit Update

Observers  on 7 April '11

A total of 26 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 11 in MPECs 2011-G51, 2011-G52, 2011-G55 & 2011-G56 -- 2011 GZ54, 2011 GZ2, 2011 GJ3, 2011 GF, 2011 GC55, 2011 GB3, 2011 GB, 2011 FS29, 2011 FG41, 2011 FB29, 2008 MN1
A74Bergen-Enkheim Obs. in Germany, 2 in MPECs 2011-G51 & 2011-G55 -- 2011 GZ2, 2011 GC55
703Catalina Sky Survey (CSS) in Arizona, 4 in MPECs 2011-G51 & 2011-G55 -- 2011 GC55, 163696, 163412, 141525
807|Robert Holmes via Cerro Tololo Inter-American Obs. in Chile, 1 in MPEC 2011-G51 -- 2011 FB29
J18Churchstoke Obs. in Wales, 1 in MPEC 2011-G51 -- 2011 GZ2
H26Doc Greiner Research Obs. (DGRO) in Wisconsin, 2 in MPEC 2011-G51 -- 2011 GF, 2011 DS9
151Eschenberg Obs. in Switzerland, 2 in MPEC 2011-G51 -- 2011 DS9, 2004 FG1
157Frasso Sabino Obs. in Italy, 1 in MPEC 2011-G51 -- 2010 VN65
J95Great Shefford Obs. in England, 2 in MPECs 2011-G54 & 2011-G55 -- 2011 GC55, 2011 GB55
A17Guidestar Obs. in Germany, 4 in MPEC 2011-G51 -- 2011 GF, 2011 GB3, 2007 PP6, 267494
704LINEAR in New Mexico, 2 in MPEC 2011-G51 -- 4954, 3554
G96Mt. Lemmon Survey (MLS) in Arizona, 5 in MPECs 2011-G51 & 2011-G54 -- 2011 GB55, 2011 FG41, 2000 PO30, 159923, 159504
A24New Millennium Obs. in Italy, 26 in MPEC 2011-G51 -- 2011 DS9, 2011 CH71, 2011 AN16, 2010 WQ7, 1999 XR35, 86667, 36284, 34613, 260141, 256412, 248083, 23187, 23183, 228368, 22771, 21374, 204232, 198856, 11885, 8507, 5869, 4954, 4660, 3554, 3122, 1864
089Nikolaev Obs. in the Ukraine, 4 in MPEC 2011-G51 -- 2010 VZ139, 2007 VC138, 1997 GL3, 250620
F51Pan-STARRS 1 (PS1) in Hawaii, 6 in MPEC 2011-G51 -- 2005 YP180, 2005 JU108, 2003 FQ6, 2000 PO30, 136874, 102873
A53Peschiera del Garda Obs. in Italy, 2 in MPEC 2011-G51 -- 2008 FT6, 228368
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 7 in MPEC 2011-G51 -- 2011 EM51, 2009 FT, 2008 FU6, 2004 FU4, 2004 FG1, 2002 TD60, 2001 QP181
D90`Kevin Hills in England via RAS Obs. Moorook in South Australia, 2 in MPEC 2011-G51 -- 2011 GM44, 2011 EW74
854Sabino Canyon Obs. in Arizona, 3 in MPECs 2011-G52, 2011-G54 & 2011-G55 -- 2011 GZ54, 2011 GC55, 2011 GB55
204Schiaparelli Obs. in Italy, 11 in MPECs 2011-G51, 2011-G52 & 2011-G55 -- 2011 GZ54, 2011 GZ2, 2011 GC55, 2011 EW74, 2011 EW29, 2011 EU20, 2011 EH17, 2011 EG17, 2010 UX7, 2008 FU6, 2003 SC11
E12Siding Spring Survey (SSS) in New South Wales, 4 in MPECs 2011-G51, 2011-G52, 2011-G53 & 2011-G54 -- 2011 GZ54, 2011 GM44, 2011 GB55, 2011 GA55
691Spacewatch 0.9m telescope in Arizona, 7 in MPEC 2011-G51 -- 2011 GD, 2007 HF44, 2007 GD49, 2006 FV35, 1998 SR49, 250706, 250620
291Spacewatch 1.8m telescope in Arizona, 4 in MPEC 2011-G51 -- 2011 GO27, 2011 GJ3, 2011 GA, 2011 FR6
I93St. Pardon de Conques Obs. in France, 2 in MPECs 2011-G54 & 2011-G55 -- 2011 GC55, 2011 GB55
6734Mike Hicks via Table Mtn. Obs. in southern California, 2 in MPECs 2011-G52 & 2011-G55 -- 2011 GZ54, 2011 GC55
A48Verona Obs. in Italy, 3 in MPEC 2011-G51 -- 2011 AN16, 2004 FG1, 267136
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 7 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.
0000NNN000

Object

Risk
Monitor
When
Noted
UTC
0000T0000
Year
Range

VI
#
000NN00
Prob
Cum
T0000
PS
Cum
T0000
PS
Max

T
S


Notes for Today's Latest Risk Assessments
2011 GA55JPL Sentry15262028-2102169.0e-09-4.68-5.120JPL: "Analysis based on 9 observations spanning 1.0670 days (2011-Apr-05.73553 to 2011-Apr-06.80255)." Diameter approximately 0.800 km. from mean, weighted H=18.1.
2011 GN44NEODyS15262014-2088752.97e-08-3.20-3.590NEODyS: "Based on 10 optical observations (of which 0 are rejected as outliers) from 2011-04-03.444 to 2011-04-06.122."
2011 GJ3JPL Sentry1526R E M O V E DJPL: Risk listing removed at 1149 UTC.
2011 GZ2NEODyS1526R E M O V E D-
JPL Sentry1526R E M O V E DJPL: Risk listing removed at 1133 UTC.
2011 GAJPL Sentry15262031-2099206.2e-08-5.01-5.310JPL: "Analysis based on 29 observations spanning 5.0352 days (2011-Apr-01.33339 to 2011-Apr-06.36854)." Diameter approximately 0.200 km. from mean, weighted H=21.1.
NEODyS15262022-2072186.83e-08-4.92-5.230NEODyS: "Based on 29 optical observations (of which 0 are rejected as outliers) from 2011-04-01.334 to 2011-04-06.369."

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 7 April '11

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

1705Grabbed MPEC 2011-G56 - 2008 MN1 - see above
1526Noted that JPL Sentry has updated its 2011 GA risk assessment - see above
Noted that NEODyS has updated its 2011 GA risk assessment - see above
Noted that JPL Sentry has posted 2011 GA55 as an impact risk - see above
Noted that JPL Sentry has removed 2011 GJ3 as an impact risk - see above
Noted that NEODyS has posted 2011 GN44 as an impact risk - see above
Noted that JPL Sentry has removed 2011 GZ2 as an impact risk - see above
Noted that NEODyS has removed 2011 GZ2 as an impact risk - see above
Grabbed MPEC 2011-G51 - Daily Orbit Update - see above
Grabbed MPEC 2011-G52 - 2011 GZ54 - see above
Grabbed MPEC 2011-G53 - 2011 GA55 - see above
Grabbed MPEC 2011-G54 - 2011 GB55 - see above
Grabbed MPEC 2011-G55 - 2011 GC55 - see above