Contents  on 26 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 26 April '09

The MPC's NEO Confirmation Page has 3 listings: 3 updated

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had three updated listings. Of these, two were "one nighters." So far The Tracking News has counted a total of nine 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 26 April '09

Minor Planet Electronic Circulars

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

MPEC 2009-H59 - "22:23 UT" - 2009 HV58

MPEC 2009-H58 - "22:21 UT" - 2009 HU58

MPEC 2009-H57 - "22:18 UT" - 2009 HT58

MPEC 2009-H56 - "16:41 UT" - Comet C/2001 D1 = 2004 X7 = 2008 S2 = 1997 J6 (SOHO)

<< DOU on 26 Apr. '09 >>  MPEC 2009-H55 - "06:09 UT" - Daily Orbit Update

Observers  on 26 April '09

A total of 22 observing facilities appear in today's MPECs.

CodeObserver / observatory
A74Bergen-Enkheim Obs. in Germany, 1 in MPEC 2009-H58 -- 2009 HU58
300Bisei Spaceguard Center in Japan, 1 in MPEC 2009-H55 -- 2009 HV44
160Castelmartini Obs. in Italy, 1 in MPEC 2009-H55 -- 2008 SV11
703Catalina Sky Survey (CSS) in Arizona, 5 in MPECs 2009-H55 & 2009-H58 -- 2009 HU58, 2009 CR2, 2008 JV19, 2000 FL1, 37655
B84Cyclops Obs. in The Netherlands, 1 in MPEC 2009-H55 -- 143651
113Drebach Obs. in Germany, 1 in MPEC 2009-H58 -- 2009 HU58
544Foerster Obs. in Germany, 1 in MPEC 2009-H55 -- 143651
J95Great Shefford Obs. in England, 4 in MPECs 2009-H55, 2009-H57 & 2009-H58 -- 2009 HV44, 2009 HU58, 2009 HT58, 2009 HB21
A17Guidestar Obs. in Germany, 1 in MPEC 2009-H58 -- 2009 HU58
118Modra Obs. in Slovakia, 1 in MPEC 2009-H58 -- 2009 HU58
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPECs 2009-H57 & 2009-H59 -- 2009 HV58, 2009 HT58
A13Naef Obs. in Switzerland, 2 in MPEC 2009-H55 -- 2009 HC, 90367
6581Dave Balam via Plaskett 1.8m Telescope in British Columbia, 1 in MPEC 2009-H58 -- 2009 HU58
D29Purple Mtn. Obs. XuYi Station in China, 1 in MPEC 2009-H55 -- 177614
473Remanzacco Obs. in Italy, 1 in MPEC 2009-H58 -- 2009 HU58
854Sabino Canyon Obs. in Arizona, 1 in MPEC 2009-H57 -- 2009 HT58
204Schiaparelli Obs. in Italy, 5 in MPEC 2009-H55 -- 2009 HD, 2009 HC, 2009 HB21, 2009 CQ1, 2002 EL6
B76Schonfeld Obs. in Germany, 1 in MPEC 2009-H55 -- 2007 BT2
2492LASCO Coronagraph 2 aboard the Solar & Heliospheric Obs. in Earth-Sun L1 HALO orbit, 1 in MPEC 2009-H56 -- C/1997 J6
291Spacewatch 1.8m telescope in Arizona, 2 in MPECs 2009-H55 & 2009-H57 -- 2009 HX51, 2009 HT58
6735Jim Young via Table Mtn. Obs. in southern California, 2 in MPECs 2009-H57 & 2009-H58 -- 2009 HU58, 2009 HT58
H53Thompsonville Obs. in Illinois, 4 in MPEC 2009-H55 -- 175706, 5604, 5011, 3554
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 26 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 HX51JPL Sentry1501R E M O V E DJPL: Risk listing removed at 0850 UTC.
NEODyS1501R E M O V E D-
2009 HCJPL Sentry15012095-209751.1e-06-6.36-6.830JPL: "Analysis based on 76 observations spanning 8.6735 days (2009-Apr-17.23164 to 2009-Apr-25.90511)." 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 26 April '09

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

2302Grabbed MPEC 2009-H57 - 2009 HT58 - see above
Grabbed MPEC 2009-H58 - 2009 HU58 - see above
Grabbed MPEC 2009-H59 - 2009 HV58 - see above
1702Grabbed MPEC 2009-H56 - Comet C/2001 D1 = 2004 X7 = 2008 S2 = 1997 J6 (SOHO) - see above
1501Noted that JPL Sentry has updated its 2009 HC risk assessment - see above
Noted that JPL Sentry has removed 2009 HX51 as an impact risk - see above
Noted that NEODyS has removed 2009 HX51 as an impact risk - see above
Grabbed MPEC 2009-H55 - Daily Orbit Update - see above