Contents  on 29 April '09


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 29 April '09

The MPC's NEO Confirmation Page has 7 listings: 2 new, 5 updated

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had two new and five updated listings. Of these, six were "one nighters." So far The Tracking News has counted a total of ten listings on the NEOCP at some point 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 29 April '09

Minor Planet Electronic Circulars

As of last check at 2358 UTC, there have been four MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2009-H80 - "15:56 UT" - 2009 HM73

MPEC 2009-H79 - "15:08 UT" - 2009 HK73

MPEC 2009-H78 - "14:12 UT" - Comet C/2009 G1 (STEREO)

<< DOU on 29 Apr. '09 >>  MPEC 2009-H77 - "06:09 UT" - Daily Orbit Update

Observers  on 29 April '09

Fourteen observing facilities appear in today's MPECs.

CodeObserver / observatory
349Ageo Obs. in Japan, 1 in MPEC 2009-H78 -- C/2009 G1
A50Andrushivka Obs. in the Ukraine, 1 in MPEC 2009-H77 -- 2008 SW150
703Catalina Sky Survey (CSS) in Arizona, 7 in MPECs 2009-H77 & 2009-H79 -- 2009 HK73, 39557, 208565, 177614, 7088, 5693, 719
J95Great Shefford Obs. in England, 1 in MPEC 2009-H77 -- 2009 HU58
379Hamamatsu-Yuto Obs. in Japan, 6 in MPEC 2009-H77 -- 2009 HV44, 2009 HG60, 2009 DE47, 2008 WL60, 2008 SV11, 2007 BT2
130Lumezzane Obs. in Italy, 2 in MPEC 2009-H77 -- 2009 CR2, 175706
900Moriyama Obs. in Japan, 1 in MPEC 2009-H79 -- 2009 HK73
G96Mt. Lemmon Survey (MLS) in Arizona, 4 in MPECs 2009-H77 & 2009-H80 -- 2009 HZ67, 2009 HM73, 2008 EN82, 212546
D29Purple Mtn. Obs. XuYi Station in China, 1 in MPEC 2009-H77 -- 2004 JN13
854Sabino Canyon Obs. in Arizona, 1 in MPEC 2009-H79 -- 2009 HK73
E12Siding Spring Survey (SSS) in New South Wales, 2 in MPEC 2009-H77 -- 2006 GQ2, 18172
691Spacewatch 0.9m telescope in Arizona, 5 in MPEC 2009-H77 -- 2009 HU2, 2008 US4, 2007 HF44, 40329, 189008
291Spacewatch 1.8m telescope in Arizona, 11 in MPECs 2009-H77 & 2009-H80 -- 2009 HY51, 2009 HV2, 2009 HU2, 2009 HM73, 2009 HE60, 2009 HC21, 2009 HC, 2009 HA21, 2009 FP29, 2009 FG19, 2009 DZ42
367Yatsuka Obs. in Japan, 1 in MPEC 2009-H78 -- C/2009 G1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 29 April '09

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2358 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. Beginning Jan. 22nd, both are also posting impact solutions beyond 100 years for a few 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
2009 HM73JPL Sentry18002020-2107129.4e-09-6.95-7.240JPL: "Analysis based on 13 observations spanning .93255 days (2009-Apr-28.37383 to 2009-Apr-29.30638)." Diameter approximately 0.087 km. from mean, weighted H=23.0.
2009 HW67NEODyS13312046-208271.38e-06-6.09-6.350NEODyS: "Based on 20 optical observations (of which 0 are rejected as outliers) from 2009/04/27.297 to 2009/04/28.249."
2009 HE60JPL Sentry1330R E M O V E DJPL: Risk listing removed at 0856 UTC.
2009 HU2NEODyS1330R E M O V E D-
JPL Sentry1330R E M O V E DJPL: Risk listing removed at 0849 UTC.
2009 HCJPL Sentry13302095-209851.3e-06-6.30-6.900JPL: "Analysis based on 97 observations spanning 11.201 days (2009-Apr-17.23164 to 2009-Apr-28.43248)." 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 29 April '09

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

1800Noted that JPL Sentry has posted 2009 HM73 as an impact risk - see above
1633Grabbed MPEC 2009-H80 - 2009 HM73 - see above
1534Grabbed MPEC 2009-H79 - 2009 HK73 - see above
1431Grabbed MPEC 2009-H78 - Comet C/2009 G1 (STEREO) - see above
1331Grabbed MPEC 2009-H77 - Daily Orbit Update - see above
1330Noted that JPL Sentry has updated its 2009 HC risk assessment - see above
Noted that JPL Sentry has removed 2009 HE60 as an impact risk - see above
Noted that JPL Sentry has removed 2009 HU2 as an impact risk - see above
Noted that NEODyS has removed 2009 HU2 as an impact risk - see above
Noted that NEODyS has posted 2009 HW67 as an impact risk - see above