Contents  on 29 April '12

Note: These A/CC news pages will update infrequently through Thursday, May 3rd, possibly less than daily.

Asteroid/Comet Connection (A/CC) 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.

Traffic Report  on 29 April '12

Four objects reported inside ten LD

Four asteroids are reported inside ten lunar distances (LD) of Earth today. Radar target 2012 HM is departing Earth's Hill sphere, traveling from 1.67 to 2.69 LD, while newly announced 2012 HE31 enters the sphere, coming infrom 4.16 to 2.83 LD.

Further away, risk-listed 2012 HP13 is outbound from 5.40 to 8.17 LD and risk-listed 2012 HG2 from 8.78 to 9.57 LD.

Approaching next, 1992 JD arrives inside ten LD tomorrow and 2010 KK37 on May 15th.

This report was updated at 1710 UTC with new discovery 2012 HE31 (MPEC) and, earlier, follow-up in today's radar for 2012 HM (MPEC) and in today's DOU MPEC for 2012 HD25, 2012 HP13, and 2012 HG2. Today's first traffic report was generated at 1456 UTC.


Notes: Ten times the distance to the Moon (ten LD) has no astronomical significance but is a useful reporting boundary. Earth's Hill sphere (of gravitational influence) is estimated to extend out to around 3.89 LD. Object distances are interpreted by A/CC from JPL Horizons data. See also current sky chart and object details (alt-details), ephemerides, and today's timeline.

Radar Astrometry  on 29 April '12

Radar observation of three objects

The JPL Solar System Dynamics Group Radar Astrometry database has added or updated the following small-body radar observing work:


Data update noted at 0450 UTC when the database was dated 28 April


Data update noted at 1437 UTC when the database was dated 28 April

NEOCP Activity  on 29 April '12

The MPC's NEO Confirmation Page has 13 listings

When last checked at 2329 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had thirteen objects listed. Of these, eight were "one nighters." So far The Tracking News has counted a total of 33 listings on the NEOCP today.

New MPECs  on 29 April '12

Minor Planet Electronic Circulars

As of last check at 2329 UTC, there have been ten MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


<< OOC on 29 Apr. '12 >> MPEC 2012-H90 - "20:07 UT" - Observations and Orbits of Comets


MPEC 2012-H89 - "15:21 UT" - 2011 JR13


MPEC 2012-H88 - "15:08 UT" - 2012 HL31


MPEC 2012-H87 - "15:06 UT" - 2012 HK31


MPEC 2012-H86 - "15:00 UT" - 2012 HJ31


MPEC 2012-H85 - "14:58 UT" - 2012 HH31


MPEC 2012-H84 - "14:56 UT" - 2012 HG31


MPEC 2012-H83 - "14:54 UT" - 2012 HF31


MPEC 2012-H82 - "14:44 UT" - 2012 HE31


<< DOU on 29 Apr. '12 >>  MPEC 2012-H81 - "06:04 UT" - Daily Orbit Update

Observers  on 29 April '12

A total of 51 observers appear in today's MPECs.

CodeObserver / observatory
J24Altamira Obs. in the Canary Islands, 7 in MPEC 2012-H90 -- C/2012 BJ98, C/2012 A2, C/2011 J2, C/2011 F1, C/2009 P1, 164P, 49P
B03Alter Satzberg Obs. in Austria, 1 in MPEC 2012-H82 -- 2012 HE31
251Arecibo in Puerto Rico, 2 in radar -- 2003 WH166, 141018
H21Astronomical Research Obs. Westfield in Illinois, 1 in MPEC 2012-H81 -- 2012 HP13
I47Auger Obs. in Argentina, 1 in MPEC 2012-H90 -- 96P
300Bisei Spaceguard Center in Japan, 1 in MPEC 2012-H84 -- 2012 HG31
I99Blanquita Obs. in Spain, 3 in MPEC 2012-H90 -- C/2011 F1, C/2009 P1, 246P
160Castelmartini Obs. in Italy, 12 in MPECs 2012-H81 & 2012-H90 -- 2012 HP13, 2012 HM, C/2012 CH17, C/2012 A2, C/2011 UF305, C/2011 F1, C/2010 S1, C/2010 R1, C/2009 P1, 24475, 246P, 49P
703Catalina Sky Survey (CSS) in Arizona, 9 in MPECs 2012-H81 & 2012-H90 -- P/2012 F2, C/2011 F1, C/2009 P1, 2003 HB6, 68348, 322652, 275558, 257P, 164P
A77Chante-Perdrix Obs. in France, 1 in MPEC 2012-H90 -- C/2012 CH17
448Desert Moon Obs. in New Mexico, 5 in MPEC 2012-H81 -- 2012 HG2, 2012 FN52, 306595, 276392, 141531
G48Doc Greiner Research Obs. Rancho Hildalgo (DGRO-RH) in New Mexico, 2 in MPEC 2012-H81 -- 2012 HJ1, 2012 HD25
I48El Catalejo Obs., 1 in MPEC 2012-H88 -- 2012 HL31
C74El Teatrillo de Lyra Obs. in Spain, 2 in MPEC 2012-H90 -- C/2010 R1, 49P
F65$Ernesto Guido in Italy via Faulkes Telescope North in Hawaii, 1 in MPEC 2012-H90 -- 67P
F65%Tim Lister in southern California via Faulkes Telescope North in Hawaii, 3 in MPECs 2012-H81 & 2012-H83 -- 2012 HF31, 2012 HD25, 2001 CQ36
C73Galati Obs. in Romania, 4 in MPECs 2012-H81 & 2012-H90 -- C/2012 B3, C/2012 A2, P/2010 JC81, 1998 HE3
252Goldstone DSS-13 34m antenna in southern California, 1 in radar -- 2012 HM
253Goldstone DSS-14 70m antenna in southern California, 1 in radar -- 2012 HM
442Gualba Obs. in Spain, 2 in MPEC 2012-H90 -- 49P, 29P
379Hamamatsu-Yuto Obs. in Japan, 3 in MPEC 2012-H81 -- 2012 AA11, 2011 YV15, 141018
857Iowa Robotic Obs. in Arizona, 1 in MPEC 2012-H90 -- C/2011 L4
C32Ka-Dar Obs. TAU Station in Russia, 16 in MPEC 2012-H90 -- P/2012 F5, C/2012 F1, C/2012 E1, C/2012 B3, C/2012 A1, C/2011 UF305, C/2011 F1, C/2010 S1, C/2010 R1, C/2010 FB87, C/2006 S3, 257P, 240P, 228P, 152P, 117P
585Kiev Comet Station in the Ukraine, 2 in MPEC 2012-H90 -- 164P, 49P
D95Kurihara Obs. in Japan, 9 in MPEC 2012-H90 -- C/2011 L4, C/2011 J2, C/2011 F1, C/2010 R1, C/2006 S3, 246P, 117P, 60P, 29P
704LINEAR in New Mexico, 9 in MPECs 2012-H81, 2012-H82 & 2012-H90 -- 2012 HE31, 2012 FE58, 2012 AA11, C/2011 L4, C/2011 J2, C/2010 R1, 86039, 68348, 152754
J31La Axarquia Obs. in Spain, 2 in MPEC 2012-H90 -- C/2011 J2, 117P
J38La Vara Obs. in Spain, 3 in MPEC 2012-H90 -- C/2009 P1, 117P, 29P
C10Maisoncelles Obs. in France, 2 in MPEC 2012-H90 -- 117P, 29P
5682David Tholen's team on Mauna Kea in Hawaii, 1 in MPEC 2012-H89 -- 2011 JR13
945Monte Deva Obs. in Spain, 4 in MPEC 2012-H90 -- C/2011 F1, C/2009 P1, 49P, 29P
900Moriyama Obs. in Japan, 14 in MPECs 2012-H81 & 2012-H90 -- 2012 HD25, C/2011 L4, C/2011 F1, C/2010 S1, C/2010 R1, C/2009 P1, C/2006 S3, 246P, 164P, 152P, 123P, 117P, 49P, 29P
G96Mt. Lemmon Survey (MLS) in Arizona, 9 in MPECs 2012-H81, 2012-H86, 2012-H87, 2012-H88 & 2012-H90 -- 2012 HL31, 2012 HK31, 2012 HJ31, P/2011 C2, 1998 KN3, 306595, 212359, 141531, 231P
A24New Millennium Obs. in Italy, 7 in MPEC 2012-H90 -- C/2012 A2, C/2011 F1, C/2010 R1, C/2009 P1, 246P, 164P, 49P
C47Nonndorf Obs. in Austria, 16 in MPECs 2012-H81 & 2012-H90 -- 2012 FY23, C/2012 CH17, C/2012 B3, C/2012 A2, 2011 WV134, C/2011 UF305, C/2011 J2, C/2011 F1, C/2010 S1, C/2010 R1, C/2009 P1, 246P, 164P, 117P, 49P, 29P
C23Olmen Obs. in Belgium, 3 in MPEC 2012-H90 -- C/2011 F1, 117P, 29P
F51Pan-STARRS 1 (PS1) in Hawaii, 23 in MPECs 2012-H81, 2012-H83, 2012-H84, 2012-H85 & 2012-H90 -- 2012 HH31, 2012 HG31, 2012 HF31, 2012 FM52, 2012 BJ11, C/2011 F1, C/2010 R1, C/2009 P1, 2009 OC, 2007 UB6, 2006 VY13, 85628, 66407, 312473, 186822, 162581, 154453, 137158, 10150, 3360, 1980, 257P, 31P
H23Pear Tree Obs. in Florida, 1 in MPEC 2012-H90 -- C/2011 F1
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 5 in MPEC 2012-H90 -- C/2012 CH17, C/2012 A2, C/2009 P1, 49P, 29P
H06_program code "_" (29) via RAS Obs. Mayhill in New Mexico, 1 in MPEC 2012-H81 -- 163000
H06`E. Bryssinck via RAS Obs. Mayhill in New Mexico, 2 in MPEC 2012-H90 -- C/2011 L4, C/2009 P1
D90`Kevin Hills in England via RAS Obs. Moorook in South Australia, 6 in MPEC 2012-H90 -- C/2012 BJ98, C/2011 L4, C/2011 J2, 246P, 123P, 29P
461SZTE Asteroid Program in Hungary, 1 in MPEC 2012-H90 -- C/2009 P1
854Sabino Canyon Obs. in Arizona, 2 in MPECs 2012-H82 & 2012-H88 -- 2012 HL31, 2012 HE31
E12Siding Spring Survey in New South Wales, 1 in MPEC 2012-H82 -- 2012 HE31
691Spacewatch 0.9m telescope in Arizona, 6 in MPECs 2012-H81 & 2012-H90 -- 2012 HL8, 2012 FD1, 2010 LJ14, 68063, 257P, 31P
291Spacewatch 1.8m telescope in Arizona, 12 in MPECs 2012-H81, 2012-H83, 2012-H84, 2012-H85, 2012-H86, 2012-H87 & 2012-H88 -- 2012 HL8, 2012 HL31, 2012 HK31, 2012 HJ31, 2012 HH31, 2012 HG31, 2012 HG2, 2012 HF31, 2012 HB25, 2012 GV17, 2012 BB124, 2010 HQ80
C36Starry Wanderer Obs., 1 in MPEC 2012-H90 -- 246P
A71Stixendorf Obs. in Austria, 12 in MPEC 2012-H90 -- C/2012 BJ98, C/2011 UF305, C/2011 Q2, C/2011 L4, C/2011 J2, C/2011 F1, C/2009 P1, C/2006 S3, 246P, 152P, 78P, 29P
A98Taurus-1 Obs. in Belarus, 6 in MPEC 2012-H90 -- C/2012 CH17, C/2012 A2, C/2011 UF305, C/2011 F1, C/2009 P1, 246P
H47Vicksburg Obs. in Mississippi, 9 in MPEC 2012-H90 -- C/2012 CH17, C/2011 L4, C/2010 R1, C/2006 S3, 246P, 152P, 117P, 49P, 29P
B42Vitebsk Obs. in Belarus, 12 in MPEC 2012-H90 -- C/2012 E3, C/2012 CH17, C/2012 B3, C/2012 A2, C/2011 UF305, C/2011 F1, C/2010 R1, C/2009 UG89, C/2007 VO53, 246P, 117P, 49P
C42Xingming Obs. in China, 3 in MPEC 2012-H90 -- C/2011 UF305, C/2011 F1, 246P
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 29 April '12

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2329 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 CLOMON2 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
2012 HJ31JPL Sentry17182059-2109123.9e-08-7.14-7.330JPL: "Analysis based on 9 observations spanning 1.0078 days (2012-Apr-28.28455 to 2012-Apr-29.29231)." Diameter approximately 0.045 km. from mean, weighted H=24.4.
2012 HE31JPL Sentry1718209411.1e-07-7.57-7.570JPL: "Analysis based on 18 observations spanning 2.2815 days (2012-Apr-27.19816 to 2012-Apr-29.479639)." Diameter approximately 0.024 km. from mean, weighted H=25.7.
2012 HB25JPL Sentry14372016-2110292.7e-05-3.90-4.290JPL: "Analysis based on 16 observations spanning 4.8694 days (2012-Apr-24.35308 to 2012-Apr-29.22248)." Diameter approximately 0.038 km. from mean, weighted H=24.8.
NEODyS14372016-2090202.97e-05-3.91-4.130NEODyS: "Based on 16 optical observations (of which 0 are rejected as outliers) from 2012-04-24.354 to 2012-04-29.223."
2012 HP13JPL Sentry14372084-209233.7e-08-7.22-7.480JPL: "Analysis based on 169 observations spanning 5.3761 days (2012-Apr-22.46032 to 2012-Apr-27.836459)." Diameter approximately 0.048 km. from mean, weighted H=24.2.
NEODyS1437R E M O V E D-
2012 HL8JPL Sentry1437R E M O V E DJPL: Risk listing removed at 0850 UTC.
2012 HG2JPL Sentry14372061-2109391.2e-05-6.16-6.350JPL: "Analysis based on 126 observations spanning 8.1118 days (2012-Apr-20.37147 to 2012-Apr-28.48326)." Diameter approximately 0.014 km. from mean, weighted H=27.0.
NEODyS14372053-20912329.61e-04-4.22-4.980NEODyS: "Based on 126 optical observations (of which 9 are rejected as outliers) from 2012-04-20.372 to 2012-04-28.484."
2012 GV17JPL Sentry1437R E M O V E DJPL: Risk listing removed at 0850 UTC.
2009 VZ39JPL Sentry03042012-21107937.0e-06-6.04-6.870JPL: "Analysis based on 8 observations spanning .04342 days (2009-Nov-10.27204 to 2009-Nov-10.31546)." Diameter approximately 0.009 km. from mean, weighted H=27.9.

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 '12

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

2329Grabbed MPEC 2012-H90 - Observations and Orbits of Comets - see above
1718Noted that JPL Sentry has posted 2012 HE31 as an impact risk - see above
Noted that JPL Sentry has posted 2012 HJ31 as an impact risk - see above
1710Updated Traffic Report
1540Grabbed MPEC 2012-H87 - 2012 HK31 - see above
Grabbed MPEC 2012-H88 - 2012 HL31 - see above
Grabbed MPEC 2012-H89 - 2011 JR13 - see above
1506Grabbed MPEC 2012-H82 - 2012 HE31 - see above
Grabbed MPEC 2012-H83 - 2012 HF31 - see above
Grabbed MPEC 2012-H84 - 2012 HG31 - see above
Grabbed MPEC 2012-H85 - 2012 HH31 - see above
Grabbed MPEC 2012-H86 - 2012 HJ31 - see above
1437Noted that JPL Sentry has removed 2012 GV17 as an impact risk - see above
Noted that JPL Sentry has updated its 2012 HB25 risk assessment - see above
Noted that NEODyS has posted 2012 HB25 as an impact risk - see above
Noted that JPL Sentry has updated its 2012 HG2 risk assessment - see above
Noted that NEODyS has updated its 2012 HG2 risk assessment - see above
Noted that JPL Sentry has removed 2012 HL8 as an impact risk - see above
Noted that JPL Sentry has updated its 2012 HP13 risk assessment - see above
Noted that NEODyS has removed 2012 HP13 as an impact risk - see above
Grabbed MPEC 2012-H81 - Daily Orbit Update - see above
Noted Radar Astrometry database update - see above
0450Noted Radar Astrometry database update - see above
0304Noted that JPL Sentry has updated its 2009 VZ39 risk assessment - see above