Contents  on 24 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 24 April '09

The MPC's NEO Confirmation Page has 8 listings: 1 new, 7 updated

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had one new and seven updated listings. Of these, six were "one nighters." So far The Tracking News has counted a total of thirteen 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 24 April '09

Minor Planet Electronic Circulars

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

MPEC 2009-H53 - "16:16 UT" - 2009 HY51

MPEC 2009-H52 - "16:12 UT" - 2009 HX51

<< DOU on 24 Apr. '09 >>  MPEC 2009-H51 - "06:09 UT" - Daily Orbit Update

Observers  on 24 April '09

A total of 23 observing facilities appear in today's MPECs.

CodeObserver / observatory
H55Astronomical Research Obs. (ARO) in Illinois, 14 in MPEC 2009-H51 -- 2009 HW2, 2009 HV2, 2009 HU2, 2009 HL21, 2009 HJ21, 2009 HH21, 2009 HF21, 2009 HE, 2009 HC, 2009 HA21, 2009 FY29, 2009 FU23, 2009 DZ, 1990 UA
069Baldone Obs. in Latvia, 1 in MPEC 2009-H51 -- 2008 OS9
621Bergisch Gladbach Obs. in Germany, 1 in MPEC 2009-H51 -- 2009 HL21
300Bisei Spaceguard Center in Japan, 1 in MPEC 2009-H51 -- 2009 HU44
160Castelmartini Obs. in Italy, 2 in MPEC 2009-H51 -- 2009 HL21, 2009 HD
703Catalina Sky Survey (CSS) in Arizona, 8 in MPECs 2009-H51 & 2009-H52 -- 2009 HX51, 2008 WL60, 2008 OB9, 86666, 155341, 144332, 7977, 3554
379Hamamatsu-Yuto Obs. in Japan, 4 in MPEC 2009-H51 -- 2009 DE47, 2008 WL60, 2008 SV11, 2007 BT2
J75La Sagra Obs. in Spain, 3 in MPEC 2009-H51 -- 2008 SW150, 89958, 143947
B90Malina River Obs. in Italy, 1 in MPEC 2009-H51 -- 2008 WL60
900Moriyama Obs. in Japan, 2 in MPEC 2009-H51 -- 2009 HV44, 2009 HU44
474Mt. John Obs. in New Zealand, 6 in MPECs 2009-H51 & 2009-H53 -- 2009 HY51, 2009 HG21, 2009 HE21, 2009 HC21, 2009 HA21, 2002 KJ3
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPEC 2009-H51 -- 2009 HC, 89355
A13Naef Obs. in Switzerland, 3 in MPECs 2009-H51 & 2009-H52 -- 2009 HX51, 2007 BF72, 89958
557Ondrejov Obs. in the Czech Republic, 1 in MPEC 2009-H51 -- 175706
A32Panker Obs. in Germany, 1 in MPEC 2009-H51 -- 2008 SV11
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 4 in MPEC 2009-H51 -- 2009 HL21, 2009 HD, 2009 CQ1, 2007 BT2
6581Dave Balam via Plaskett 1.8m Telescope in British Columbia, 1 in MPEC 2009-H52 -- 2009 HX51
854Sabino Canyon Obs. in Arizona, 1 in MPEC 2009-H52 -- 2009 HX51
H36Sandlot Obs. in Kansas, 1 in MPEC 2009-H53 -- 2009 HY51
204Schiaparelli Obs. in Italy, 3 in MPEC 2009-H51 -- 2009 FL25, 2009 FJ30, 2009 CQ1
691Spacewatch 0.9m telescope in Arizona, 4 in MPECs 2009-H51 & 2009-H53 -- 2009 HY51, 2009 HU2, 2005 SA71, 2003 WO7
291Spacewatch 1.8m telescope in Arizona, 6 in MPECs 2009-H51, 2009-H52 & 2009-H53 -- 2009 HY51, 2009 HX51, 2009 HV2, 2009 HU2, 2009 FG19, 1990 UA
611Starkenburg Obs. in Germany, 1 in MPEC 2009-H52 -- 2009 HX51
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 24 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 Sentry19002019-21081525.2e-07-4.20-4.670JPL: "Analysis based on 21 observations spanning .99569 days (2009-Apr-23.35742 to 2009-Apr-24.35311)." Diameter approximately 0.200 km. from mean, weighted H=21.1.
2009 HA21JPL Sentry1334R E M O V E DJPL: Risk listing removed at 0857 UTC.
NEODyS1334R E M O V E D-
2009 HU2NEODyS13342065-206723.8e-09-5.08-5.270NEODyS: "Based on 43 optical observations (of which 0 are rejected as outliers) from 2009/04/19.132 to 2009/04/24.175."
2009 HCJPL Sentry13342095-209741.0e-06-6.41-6.870JPL: "Analysis based on 65 observations spanning 6.0874 days (2009-Apr-17.23164 to 2009-Apr-23.319008)." 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 24 April '09

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

1900Noted that JPL Sentry has posted 2009 HX51 as an impact risk - see above
1641Grabbed MPEC 2009-H52 - 2009 HX51 - see above
Grabbed MPEC 2009-H53 - 2009 HY51 - see above
1334Noted that JPL Sentry has removed 2009 HA21 as an impact risk - see above
Noted that NEODyS has removed 2009 HA21 as an impact risk - see above
Noted that JPL Sentry has updated its 2009 HC risk assessment - see above
Noted that NEODyS has reposted 2009 HU2 as an impact risk - see above
Grabbed MPEC 2009-H51 - Daily Orbit Update - see above