Contents  on 19 April '12

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 19 April '12

Five objects reported inside ten LD

Five asteroids are reported to be within ten lunar distances (LD) of our planet today. 2007 HV4, which hasn't been reported observed yet, may be coming its closest to Earth on this passage, reaching perhaps 4.8 LD, but with an uncertainty of +/- 1.748 days. Newly discovered 2012 HN1 is inbound from 5.98 to 5.49 LD, 2012 GW11 is headed away from 5.09 to 7.11 LD, 2012 HE enters ten LD, traveling from 10.07 to 8.68 LD, and radar target 2012 GP1 moves from 9.28 to 9.06 LD.

Coming toward Earth next, radar target 2012 HM arrives inside ten LD on April 21st, risk-listed 2012 HQ on April 23rd, and 1992 JD on April 30th (uncertainty +/- 4.600 hours).

This report was updated at 2116 UTC with new discovery 2012 HN1 (MPEC) in addition to follow-up in today's DOU MPEC for 2012 HN, 2012 HM, 2012 GW11, and 2012 DA14. Today's first traffic report was generated at 1542 UTC.

Notes: Ten times the distance to the Moon (ten LD) has no astronomical significance but is a useful reporting boundary. 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.

NEOCP Activity  on 19 April '12

The MPC's NEO Confirmation Page has 23 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 23 objects listed. Of these, sixteen were "one nighters." So far The Tracking News has counted a total of 35 listings on the NEOCP 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 19 April '12

Minor Planet Electronic Circulars

As of last check at 2359 UTC, there have been five MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2012-H26 - "19:36 UT" - 2012 HO1

MPEC 2012-H25 - "19:31 UT" - 2012 HN1

MPEC 2012-H24 - "19:29 UT" - 2012 HM1

MPEC 2012-H23 - "16:33 UT" - 2012 HJ1

<< DOU on 19 Apr. '12 >>  MPEC 2012-H22 - "06:03 UT" - Daily Orbit Update

Observers  on 19 April '12

A total of 20 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 18 in MPECs 2012-H22, 2012-H23, 2012-H24, 2012-H25 & 2012-H26 -- 2012 HO1, 2012 HO, 2012 HN1, 2012 HM1, 2012 HJ1, 2012 GW11, 2012 FZ44, 2012 FZ23, 2012 FW23, 2012 FR52, 2012 FR35, 2012 FN62, 2012 FC1, 2012 DK61, 2012 DF61, 2012 BK77, 2011 QD48, 2008 CD22
703Catalina Sky Survey (CSS) in Arizona, 13 in MPECs 2012-H22, 2012-H23 & 2012-H25 -- 2012 HN1, 2012 HJ1, 2012 GC2, 68267, 322775, 312942, 306595, 231937, 212359, 171819, 154658, 6455, 3352
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 7 in MPECs 2012-H22, 2012-H23 & 2012-H24 -- 2012 HO, 2012 HM1, 2012 HL, 2012 HK, 2012 HJ1, 2012 GE5, 2011 US63
821Cordoba Obs. Bosque Alegre Station in Argentina, 1 in MPEC 2012-H23 -- 2012 HJ1
I39Cruz del Sur Obs. in Argentina, 1 in MPEC 2012-H22 -- 2001 SZ269
448Desert Moon Obs. in New Mexico, 2 in MPEC 2012-H22 -- 2012 GK, 2012 FB57
G48Doc Greiner Research Obs. Rancho Hildalgo (DGRO-RH) in New Mexico, 3 in MPEC 2012-H22 -- 2012 HM, 2012 HK, 2012 GC2
F65%Tim Lister in southern California via Faulkes Telescope North in Hawaii, 1 in MPEC 2012-H24 -- 2012 HM1
704LINEAR in New Mexico, 6 in MPEC 2012-H22 -- 85275, 68267, 53110, 322966, 312942, 4055
H01Magdalena Ridge Obs. (MRO) in New Mexico, 4 in MPECs 2012-H23, 2012-H24, 2012-H25 & 2012-H26 -- 2012 HO1, 2012 HN1, 2012 HM1, 2012 HJ1
900Moriyama Obs. in Japan, 1 in MPEC 2012-H22 -- 2001 SZ269
474Mt. John Obs. in New Zealand, 1 in MPEC 2012-H23 -- 2012 HJ1
G84Mt. Lemmon SkyCenter in Arizona, 1 in MPEC 2012-H22 -- 2009 KL2
G96Mt. Lemmon Survey (MLS) in Arizona, 10 in MPECs 2012-H22, 2012-H25 & 2012-H26 -- 2012 HO1, 2012 HN1, 2004 OB, 38086, 318450, 318160, 163000, 162422, 136874, 112985
644NEAT's Mt. Palomar telescope in southern California, 1 in MPEC 2012-H22 -- 2012 GG1
F51Pan-STARRS 1 in Hawaii, 1 in MPEC 2012-H24 -- 2012 HM1
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 8 in MPEC 2012-H22 -- 2012 HM, 2012 GC2, 2012 FY23, 2012 ES14, 2012 DO, 2012 AA11, 2011 YV15, 2011 QD48
H36Sandlot Obs. in Kansas, 2 in MPECs 2012-H23 & 2012-H25 -- 2012 HN1, 2012 HJ1
691Spacewatch 0.9m telescope in Arizona, 2 in MPEC 2012-H22 -- 189008, 186822
291Spacewatch 1.8m telescope in Arizona, 13 in MPEC 2012-H22 -- 2012 HN, 2012 GX11, 2012 GV11, 2012 GK, 2012 GG1, 2012 GA5, 2012 FL35, 2012 FA14, 2012 DV32, 2012 DA14, 2012 CM29, 2012 BB77, 2009 HC82
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 19 April '12

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 CLOMON2 risk pages.





Notes for Today's Latest Risk Assessments
2012 DA14JPL Sentry15412020-21122146.8e-04-2.92-3.560JPL: "Analysis based on 178 observations spanning 55.375 days (2012-Feb-23.03431 to 2012-Apr-18.40923)." Diameter approximately 0.045 km. from mean, weighted H=24.4.
NEODyS15412020-20902184.89e-04-3.01-3.550NEODyS: "Based on 181 optical observations (of which 4 are rejected as outliers) from 2012-02-23.029 to 2012-04-18.410."

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 19 April '12

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

2116Updated Traffic Report
2030Grabbed MPEC 2012-H24 - 2012 HM1 - see above
Grabbed MPEC 2012-H25 - 2012 HN1 - see above
Grabbed MPEC 2012-H26 - 2012 HO1 - see above
1703Grabbed MPEC 2012-H23 - 2012 HJ1 - see above
1541Noted that JPL Sentry has updated its 2012 DA14 risk assessment - see above
Noted that NEODyS has updated its 2012 DA14 risk assessment - see above
Grabbed MPEC 2012-H22 - Daily Orbit Update - see above