Contents  on 20 April '09

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 20 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 eighteen 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 20 April '09

Minor Planet Electronic Circulars

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


MPEC 2009-H24 - "17:40 UT" - 2009 HW2


MPEC 2009-H23 - "17:37 UT" - 2009 HV2


MPEC 2009-H22 - "17:23 UT" - 2009 HU2


MPEC 2009-H21 - "17:12 UT" - 2009 HT2


MPEC 2009-H20 - "17:00 UT" - 2009 HS2


MPEC 2009-H19 - "16:55 UT" - 2009 HR2


<< DOU on 20 Apr. '09 >>  MPEC 2009-H18 - "06:07 UT" - Daily Orbit Update

Observers  on 20 April '09

A total of 24 observing facilities appear in today's MPECs.

CodeObserver / observatory
J16An Carraig Obs. in Northern Ireland, 1 in MPEC 2009-H18 -- 2007 BT2
703Catalina Sky Survey (CSS) in Arizona, 4 in MPEC 2009-H18 -- 2009 EQ2, 2009 CO5, 2004 JN13, 175706
448Desert Moon Obs. in New Mexico, 2 in MPEC 2009-H18 -- 2009 FU4, 2009 FG19
113Drebach Obs. in Germany, 2 in MPEC 2009-H18 -- 2009 CQ1, 5011
I21El Condor Obs. in Argentina, 2 in MPEC 2009-H18 -- 2009 FJ30, 2008 SV11
B21Gaisberg Obs. in Austria, 1 in MPEC 2009-H21 -- 2009 HT2
651Grasslands Obs. in Arizona, 2 in MPECs 2009-H19 & 2009-H23 -- 2009 HV2, 2009 HR2
J95Great Shefford Obs. in England, 3 in MPECs 2009-H21, 2009-H22 & 2009-H23 -- 2009 HV2, 2009 HU2, 2009 HT2
A17Guidestar Obs. in Germany, 1 in MPEC 2009-H23 -- 2009 HV2
B15Inastars Obs. in Germany, 1 in MPEC 2009-H23 -- 2009 HV2
B12Koschny Obs. in The Netherlands, 5 in MPEC 2009-H18 -- 143651, 5332, 5011, 4257, 3554
704LINEAR in New Mexico, 10 in MPEC 2009-H18 -- 2009 HD, 2009 FY29, 2008 WL60, 2000 KN44, 85938, 35107, 138127, 5332, 3103, 1863
H01Magdalena Ridge Obs. (MRO) in New Mexico, 6 in MPECs 2009-H19, 2009-H20, 2009-H21, 2009-H22, 2009-H23 & 2009-H24 -- 2009 HW2, 2009 HV2, 2009 HU2, 2009 HT2, 2009 HS2, 2009 HR2
B82Maidbronn Obs. in Germany, 1 in MPEC 2009-H18 -- 198856
G96Mt. Lemmon Survey (MLS) in Arizona, 11 in MPECs 2009-H18, 2009-H19, 2009-H20, 2009-H21, 2009-H22, 2009-H23 & 2009-H24 -- 2009 HW2, 2009 HV2, 2009 HU2, 2009 HT2, 2009 HS2, 2009 HR2, 2007 BF72, 2003 UN12, 1998 WT30, 19764, 3554
J93Mt. Tuffley Obs. in England, 5 in MPEC 2009-H18 -- 2008 WL60, 2008 SV11, 143651, 5604, 1036
644NEAT's Mt. Palomar telescope in southern California, 1 in MPEC 2009-H18 -- 2008 YR2
A32Panker Obs. in Germany, 1 in MPEC 2009-H18 -- 2008 SV11
J41Raheny Obs. in Ireland, 1 in MPEC 2009-H23 -- 2009 HV2
H36Sandlot Obs. in Kansas, 2 in MPECs 2009-H22 & 2009-H23 -- 2009 HV2, 2009 HU2
691Spacewatch 0.9m telescope in Arizona, 3 in MPECs 2009-H19, 2009-H22 & 2009-H23 -- 2009 HV2, 2009 HU2, 2009 HR2
291Spacewatch 1.8m telescope in Arizona, 14 in MPECs 2009-H18, 2009-H19, 2009-H20, 2009-H22, 2009-H23 & 2009-H24 -- 2009 HW2, 2009 HV2, 2009 HU2, 2009 HS2, 2009 HR2, 2009 HE, 2009 HC, 2009 FN28, 2009 FG19, 2009 ES, 2009 DZ42, 2009 CB3, 2003 UN12, 2001 SF262
6735Jim Young via Table Mtn. Obs. in southern California, 2 in MPECs 2009-H22 & 2009-H23 -- 2009 HV2, 2009 HU2
198Wildberg Obs. in Germany, 2 in MPECs 2009-H22 & 2009-H23 -- 2009 HV2, 2009 HU2
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 20 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.
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
2009 HU2JPL Sentry19012041-2067233.8e-08-4.07-5.140JPL: "Analysis based on 28 observations spanning 1.1594 days (2009-Apr-19.13168 to 2009-Apr-20.29109)." Diameter approximately 0.796 km. from mean, weighted H=18.1.
2009 HEJPL Sentry1318R E M O V E DJPL: Risk listing removed at 0853 UTC.
NEODyS1318R E M O V E D-
2009 HCJPL Sentry13182093-209869.3e-07-6.44-6.950JPL: "Analysis based on 40 observations spanning 2.1572 days (2009-Apr-17.23164 to 2009-Apr-19.38884)." 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 20 April '09

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

1902Grabbed MPEC 2009-H23 - 2009 HV2 - see above
Grabbed MPEC 2009-H24 - 2009 HW2 - see above
1901Noted that JPL Sentry has posted 2009 HU2 as an impact risk - see above
1737Grabbed MPEC 2009-H19 - 2009 HR2 - see above
Grabbed MPEC 2009-H20 - 2009 HS2 - see above
Grabbed MPEC 2009-H21 - 2009 HT2 - see above
Grabbed MPEC 2009-H22 - 2009 HU2 - see above
1318Noted that JPL Sentry has updated its 2009 HC risk assessment - see above
Noted that JPL Sentry has removed 2009 HE as an impact risk - see above
Noted that NEODyS has removed 2009 HE as an impact risk - see above
Grabbed MPEC 2009-H18 - Daily Orbit Update - see above