Contents  on 31 December '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 31 December '12

One object reported inside ten LD

One object is reported to be within ten lunar distances (LD) of Earth today. Radar target 2012 XM55 is outbound from 5.44 to 5.97 LD. The next known object to be coming inside ten LD is intruder 2012 DA14, a risk-listed radar target that arrives on February 8th.

This report was generated at 1619 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 31 December '12

The MPC's NEO Confirmation Page has 30 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 30 objects listed. Of these, 21 were "one nighters." So far The Tracking News has counted a total of 39 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 31 December '12

Minor Planet Electronic Circulars

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

MPEC 2012-Y43 - "06:18 UT" - Numbering of Periodic Comets 272P-275P

MPEC 2012-Y42 - "13:23 UT" - 2012 YY6

<< DOU on 31 Dec. '12 >>  MPEC 2012-Y41 - "06:02 UT" - Daily Orbit Update

Observers  on 31 December '12

Seventeen observers appear in today's MPECs.

CodeObserver / observatory
300Bisei Spaceguard Center in Japan, 1 in MPEC 2012-Y42 -- 2012 YY6
470Ceccano Obs. in Italy, 1 in MPEC 2012-Y41 -- 99942
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 2 in MPEC 2012-Y41 -- 2012 QP17, 2012 ML6
595Farra d'Isonzo Obs. in Italy, 1 in MPEC 2012-Y42 -- 2012 YY6
J95Great Shefford Obs. in England, 1 in MPEC 2012-Y42 -- 2012 YY6
C43Hoyerswerda Obs. in Germany, 1 in MPEC 2012-Y42 -- 2012 YY6
D95Kurihara Obs. in Japan, 1 in MPEC 2012-Y41 -- 4179
5682David Tholen's team on Mauna Kea in Hawaii, 1 in MPEC 2012-Y41 -- 2012 US68
566NEAT's GEODSS Haleakala telescope in Hawaii, 1 in MPEC 2012-Y41 -- 2012 TA219
A24New Millennium Obs. in Italy, 1 in MPEC 2012-Y42 -- 2012 YY6
C47Nonndorf Obs. in Austria, 2 in MPEC 2012-Y41 -- 154347, 4179
F51Pan-STARRS 1 (PS1) in Hawaii, 3 in MPECs 2012-Y41 & 2012-Y42 -- 2012 YY6, 99942, 189011
A32Panker Obs. in Germany, 2 in MPEC 2012-Y41 -- 5836, 5587
H36Sandlot Obs. in Kansas, 1 in MPEC 2012-Y42 -- 2012 YY6
204Schiaparelli Obs. in Italy, 1 in MPEC 2012-Y42 -- 2012 YY6
I93St. Pardon de Conques Obs. in France, 1 in MPEC 2012-Y42 -- 2012 YY6
C92Valdicerro Obs. in Italy, 1 in MPEC 2012-Y42 -- 2012 YY6
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 31 December '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 UE34NEODyS16162095-210051.16e-06-5.44-5.530NEODyS: "Based on 44 optical observations (of which 0 are rejected as outliers) from 2012-10-18.394 to 2012-12-13.332."

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 31 December '12

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

1645Grabbed MPEC 2012-Y43 - Numbering of Periodic Comets 272P-275P - see above
1619Generated Traffic Report
1616Noted that NEODyS has updated its 2012 UE34 risk assessment - see above
Grabbed MPEC 2012-Y41 - Daily Orbit Update - see above
Grabbed MPEC 2012-Y42 - 2012 YY6 - see above