Contents  on 30 April '11

Resources:

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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 30 April '11

The Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) was not checked on this day.

New MPECs  on 30 April '11

Minor Planet Electronic Circulars

There were ten MPECs posted this day from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


MPEC 2011-H64 - "22:11 UT" - 2011 HC36


MPEC 2011-H63 - "12:29 UT" - 2011 HP24


MPEC 2011-H62 - "12:23 UT" - 2011 HO24


MPEC 2011-H61 - "12:17 UT" - 2011 HN24


MPEC 2011-H60 - "11:20 UT" - 2011 HE24


<< DOU on 30 Apr. '11 >>  MPEC 2011-H59 - "07:07 UT" - Daily Orbit Update


MPEC 2011-H58 - "02:33 UT" - 36 New TNOs


MPEC 2011-H57 - "02:23 UT" - 2011 HD24


MPEC 2011-H56 - "02:06 UT" - 2011 HC24


MPEC 2011-H55 - "00:44 UT" - Ten TNO Recoveries

Observers  on 30 April '11

A total of 23 observers appeared in this day's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 7 in MPECs 2011-H59, 2011-H60, 2011-H63 & 2011-H64 -- 2011 HT, 2011 HS4, 2011 HP24, 2011 HH1, 2011 HE24, 2011 HC36, 2011 GB3
703Catalina Sky Survey (CSS) in Arizona, 5 in MPEC 2011-H59 -- 2011 HO4, 2011 GL62, 271480, 260141, 141432
3092Brett Gladman via Cerro Paranal in Chile, 6 in MPECs 2011-H55 & 2011-H58 -- 2006 JU58, 2005 JB186, 2004 PV117, 2004 KJ19, 2004 KH19, 2004 KE19
8074Jean-Marc Petit & JJ Kavelaars via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 6 in MPEC 2011-H58 -- 2004 PW117, 2004 MV8, 2004 KH19, 2004 KF19, 2004 KE19, 2004 HC79
807|Robert Holmes via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 4 in MPECs 2011-H56 & 2011-H59 -- 2011 HP, 2011 HC24, 2011 GA62, 2008 CM
F65%Tim Lister in southern California via Faulkes Telescope North in Hawaii, 2 in MPECs 2011-H60 & 2011-H62 -- 2011 HO24, 2011 HE24
6958J.W. Parker via Kitt Peak Natl. Obs. (KPNO) in Arizona, 24 in MPECs 2011-H55 & 2011-H58 -- 2007 DS101, 2007 CS79, 2007 CR79, 2007 CQ79, 2006 WF206, 2006 JV58, 2006 JU58, 2006 CH69, 2005 LB54, 2005 LA54, 2005 JY185, 2005 JJ186, 2004 VD131, 2004 VC131, 2004 VA131, 2004 QF29, 2004 QD29, 2004 PV117, 2004 MU8, 2004 KE19, 2004 HL79, 2004 HK79, 2004 HJ79, 2004 HD79
704LINEAR in New Mexico, 12 in MPEC 2011-H59 -- 2011 GC60, 89958, 86667, 53435, 267494, 248083, 22771, 141531, 3103, 1917, 1866, 1036
950/Brett Gladman via La Palma in the Canary Islands, 4 in MPEC 2011-H58 -- 2004 VC131, 2004 VB131, 2004 QD29, 2004 PW117
8096Jean-Marc Petit via La Silla in Chile, 5 in MPEC 2011-H58 -- 2004 PV117, 2004 PU117, 2004 KJ19, 2004 KG19, 2004 HF79
568{JJ Kavelaars on Mauna Kea in Hawaii, 46 in MPECs 2011-H55 & 2011-H58 -- 2007 DS101, 2007 CS79, 2007 CR79, 2007 CQ79, 2006 WF206, 2006 JV58, 2006 JU58, 2006 HA123, 2006 CH69, 2005 LB54, 2005 LA54, 2005 JY185, 2005 JJ186, 2005 JB186, 2005 CE81, 2005 BW49, 2005 BV49, 2004 VD131, 2004 VC131, 2004 VB131, 2004 VA131, 2004 QF29, 2004 QE29, 2004 QD29, 2004 PX117, 2004 PW117, 2004 PV117, 2004 PU117, 2004 PT117, 2004 MV8, 2004 MU8, 2004 MT8, 2004 KJ19, 2004 KH19, 2004 KG19, 2004 KF19, 2004 KE19, 2004 HL79, 2004 HK79, 2004 HJ79, 2004 HH79, 2004 HG79, 2004 HF79, 2004 HE79, 2004 HD79, 2004 HC79
474Mt. John Obs. in New Zealand, 1 in MPEC 2011-H56 -- 2011 HC24
G96Mt. Lemmon Survey (MLS) in Arizona, 11 in MPECs 2011-H56, 2011-H57, 2011-H59, 2011-H61 & 2011-H63 -- 2011 HP24, 2011 HN24, 2011 HD24, 2011 HC24, 2006 YN, 2002 DY3, 2000 CO101, 65803, 250706, 7753, 4401
6758Brett Gladman via Mt. Palomar in southern California, 21 in MPECs 2011-H55 & 2011-H58 -- 2007 CS79, 2007 CQ79, 2006 WF206, 2006 HA123, 2005 LA54, 2005 JY185, 2005 JJ186, 2005 CE81, 2004 VA131, 2004 QF29, 2004 QE29, 2004 QD29, 2004 PU117, 2004 PT117, 2004 MV8, 2004 MU8, 2004 MT8, 2004 HK79, 2004 HJ79, 2004 HH79, 2004 HE79
A24New Millennium Obs. in Italy, 9 in MPEC 2011-H59 -- 2011 AN16, 2008 SO, 2007 TB23, 2004 FG1, 89830, 40267, 267136, 23187, 4954
F51Pan-STARRS 1 (PS1) in Hawaii, 9 in MPECs 2011-H59, 2011-H60, 2011-H61, 2011-H62 & 2011-H64 -- 2011 HO24, 2011 HN24, 2011 HE24, 2011 HC36, 2011 GB55, 2010 VN65, 2005 WD1, 1998 HK49, 86326
H06|Hidetaka Sato in Japan via RAS Obs. Mayhill in New Mexico, 1 in MPEC 2011-H59 -- 5496
233San Vito Obs. in Italy, 1 in MPEC 2011-H59 -- 260141
691Spacewatch 0.9m telescope in Arizona, 5 in MPECs 2011-H59 & 2011-H61 -- 2011 HN24, 2011 HF, 86326, 250620, 4401
291Spacewatch 1.8m telescope in Arizona, 5 in MPECs 2011-H59, 2011-H61 & 2011-H62 -- 2011 HO24, 2011 HN24, 2011 DU, 2011 BX10, 2000 TU28
I93St. Pardon de Conques Obs. in France, 2 in MPECs 2011-H56 & 2011-H57 -- 2011 HD24, 2011 HC24
926Tenagra II Obs. in Arizona, 1 in MPEC 2011-H64 -- 2011 HC36
G56Walnut Creek Obs. in northern California, 3 in MPEC 2011-H59 -- 2011 HS, 2011 HQ, 2011 HH1
696#Brett Gladman via Whipple Obs. in Arizona, 1 in MPEC 2011-H58 -- 2004 PT117
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 30 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 HP24JPL Sentry15592020-21081812.9e-06-5.81-6.340JPL: "Analysis based on 11 observations spanning .88829 days (2011-Apr-28.43605 to 2011-Apr-29.324345)." Diameter approximately 0.027 km. from mean, weighted H=25.5.
2011 HS4JPL Sentry1559209511.0e-09-6.89-6.890JPL: "Analysis based on 25 observations spanning 2.9367 days (2011-Apr-26.43641 to 2011-Apr-29.37311)." Diameter approximately 0.240 km. from mean, weighted H=20.7.

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 30 April '11

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

2300Grabbed MPEC 2011-H64 - 2011 HC36 - see above
1559Noted that JPL Sentry has posted 2011 HP24 as an impact risk - see above
Noted that JPL Sentry has posted 2011 HS4 as an impact risk - see above
Grabbed MPEC 2011-H59 - Daily Orbit Update - see above
Grabbed MPEC 2011-H60 - 2011 HE24 - see above
Grabbed MPEC 2011-H61 - 2011 HN24 - see above
Grabbed MPEC 2011-H62 - 2011 HO24 - see above
Grabbed MPEC 2011-H63 - 2011 HP24 - see above
0244Grabbed MPEC 2011-H57 - 2011 HD24 - see above
Grabbed MPEC 2011-H58 - 36 New TNOs - see above
0215Grabbed MPEC 2011-H56 - 2011 HC24 - see above
0109Grabbed MPEC 2011-H55 - Ten TNO Recoveries - see above