Contents  on 29 January '12

Note: These A/CC news pages will update less often and less regularly than usual through Tuesday, January 31st, possibly later.


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 January '12

Three objects reported inside ten LD

There are three objects reported moving inside ten lunar distances (LD) of Earth today. Intruder 2012 BX34 exits Earth's Hill sphere. Further out, 2012 BD14 travels from 6.56 to 5.97 LD and risk-listed 2012 BW13 leaves ten LD, moving from 7.47 to 10.06 LD.

Next up, radar target 2011 CP4 arrives inside ten LD on February 22nd.

This report was updated at 1546 UTC with follow-up in today's DOU MPEC for 2012 BX34, 2012 BF27, 2012 BO11, and 2011 YH40. This report was previously updated at 0343 UTC.

Notes: Ten LD has no astronomical significance but is a useful reporting boundary. Earth's Hill sphere (of gravitational influence) has a radius estimated at about 3.89 LD. Distances are interpreted by A/CC from JPL Horizons data. See also today's timeline plus current additional details, sky chart, and ephemerides.

NEOCP Activity  on 29 January '12

The MPC's NEO Confirmation Page has 52 listings

When last checked at 2236 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 52 objects listed. Of these, 23 were "one nighters."

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 29 January '12

Minor Planet Electronic Circulars

As of last check at 2236 UTC, there have been three MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

<< DOU on 29 Jan. '12 >>  MPEC 2012-B98 - "06:05 UT" - Daily Orbit Update

MPEC 2012-B97 - "03:00 UT" - S/2011 J 1 and S/2011 J 2

MPEC 2012-B96 - "02:01 UT" - P/2003 T12 = 2012 A3 (SOHO)

Observers  on 29 January '12

Thirteen observers appear in today's MPECs.

CodeObserver / observatory
B37Ametlla del Valles Obs. in Spain, 1 in MPEC 2012-B98 -- 138175
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 2 in MPEC 2012-B98 -- 2012 BT23, 2011 SR69
448Desert Moon Obs. in New Mexico, 10 in MPEC 2012-B98 -- 2012 BT23, 2012 BN11, 2012 AU10, 2011 YU74, 311044, 184990, 163696, 163000, 141056, 137099
G48Doc Greiner Research Obs. Rancho Hildalgo (DGRO-RH) in New Mexico, 2 in MPEC 2012-B98 -- 2011 WV134, 2011 SL102
F65%Tim Lister in southern California via Faulkes Telescope North in Hawaii, 1 in MPEC 2012-B98 -- 2012 BC77
E16Grove Creek Obs. in New South Wales, 2 in MPEC 2012-B98 -- 2012 BT23, 2011 YU62
A24New Millennium Obs. in Italy, 39 in MPEC 2012-B98 -- 2012 BX34, 2011 YU74, 2011 XO3, 2011 WV134, 2011 SL102, 2008 WZ13, 2008 GE1, 2005 NJ1, 2003 BL1, 1996 AE2, 99799, 90147, 85839, 36284, 32906, 294739, 29075, 289315, 24475, 21088, 209924, 20826, 202435, 175706, 163696, 163000, 162186, 142348, 137805, 10145, 8567, 7358, 6050, 3200, 2368, 1943, 1866, 1627, 1620
F51Pan-STARRS 1 in Hawaii, 1 in MPEC 2012-B98 -- 204232
C50STEREO-B in heliocentric orbit trailing Earth, 1 in MPEC 2012-B96 -- P/2012 A3
204Schiaparelli Obs. in Italy, 8 in MPEC 2012-B98 -- 2012 AE3, 2011 YH40, 2011 YH28, 2011 YB40, 2011 RR12, 2011 LD19, 2007 LE, 2002 AX1
691Spacewatch 0.9m telescope in Arizona, 1 in MPEC 2012-B98 -- 2012 AC13
291Spacewatch 1.8m telescope in Arizona, 5 in MPEC 2012-B98 -- 2012 BU61, 2012 BO11, 2012 BN11, 2012 BF27, 2011 WL2
G56Walnut Creek Obs. in northern California, 2 in MPEC 2012-B98 -- 2012 BJ11, 2012 AE1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 29 January '12

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2236 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 BC77NEODyS1421R E M O V E D-
JPL Sentry1421R E M O V E DJPL: Risk listing removed at 0851 UTC.
2012 BU61JPL Sentry14212031-2110207.8e-07-3.94-4.390JPL: "Analysis based on 23 observations spanning 3.0384 days (2012-Jan-26.0941 to 2012-Jan-29.13247)." Diameter approximately 0.212 km. from mean, weighted H=21.0.
NEODyS14212031-2090127.2e-07-4.08-4.290NEODyS: "Based on 23 optical observations (of which 0 are rejected as outliers) from 2012-01-26.095 to 2012-01-29.133."
2012 BF27JPL Sentry1421R E M O V E DJPL: Risk listing removed at 0852 UTC.
2012 BO11JPL Sentry1421209315.9e-08-7.93-7.930JPL: "Analysis based on 39 observations spanning 9.0317 days (2012-Jan-19.49216 to 2012-Jan-28.52384)." Diameter approximately 0.024 km. from mean, weighted H=25.8.
NEODyS1421R E M O V E D-
2011 WL2JPL Sentry1421209819.3e-07-4.22-4.220JPL: "Analysis based on 206 observations spanning 73.800 days (2011-Nov-16.31883 to 2012-Jan-29.11929)." 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 29 January '12

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

1546Updated Traffic Report
1421Noted that JPL Sentry has updated its 2011 WL2 risk assessment - see above
Noted that JPL Sentry has removed 2012 BC77 as an impact risk - see above
Noted that NEODyS has removed 2012 BC77 as an impact risk - see above
Noted that JPL Sentry has removed 2012 BF27 as an impact risk - see above
Noted that JPL Sentry has reposted 2012 BO11 as an impact risk - see above
Noted that NEODyS has removed 2012 BO11 as an impact risk - see above
Noted that JPL Sentry has updated its 2012 BU61 risk assessment - see above
Noted that NEODyS has updated its 2012 BU61 risk assessment - see above
Grabbed MPEC 2012-B98 - Daily Orbit Update - see above
0341Grabbed MPEC 2012-B96 - P/2003 T12 = 2012 A3 (SOHO) - see above
Grabbed MPEC 2012-B97 - S/2011 J 1 and S/2011 J 2 - see above