Contents  on 6 December '13

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 6 December '13

No objects reported inside ten LD

No objects are reported moving within a radius of ten lunar distances (LD) from Earth today. Next known to be approaching is 2011 YD29, calculated with large uncertainty to enter our ten-LD reporting "bubble" on December 23rd.

This report was updated at 1758 UTC with follow-up in today's DOU MPEC for risk-listed objects 2013 WZ44, 2013 WX44, and 2013 VJ13, as well as 2013 WY and radar target 2013 NJ, plus observation of 2013 UV3 and 2013 UT3 from late October. Today's first traffic report was generated at 1553 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 6 December '13

The MPC's NEO Confirmation Page has 44 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 44 objects listed. Of these, 22 were "one nighters." So far The Tracking News has counted a total of 54 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 6 December '13

Minor Planet Electronic Circulars

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

MPEC 2013-X29 - "17:46 UT" - Comet C/2013 X1 (Panstarrs)

<< DOU on 6 Dec. '13 >>  MPEC 2013-X28 - "17:33 UT" - Daily Orbit Update

Observers  on 6 December '13

Seventeen observers appear in today's MPECs.

CodeObserver / observatory
I99Blanquita Obs. in Spain, 2 in MPEC 2013-X28 -- 52760, 137062
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 10 in MPEC 2013-X28 -- 2013 WT44, 2013 WC44, 2013 VV4, 2013 VP12, 2013 VM4, 2013 VF13, 2013 SF, 2013 LW28, 2010 OQ1, 2008 SQ1
J27El Guijo Obs. in Spain, 5 in MPEC 2013-X28 -- 2013 UR3, 85818, 251346, 16834, 162004
Z81Estrella de Mar Obs., 2 in MPEC 2013-X28 -- 2013 WH, 237805
695]Mark Trueblood via Kitt Peak Natl. Obs. (KPNO) in Arizona, 16 in MPEC 2013-X28 -- 2013 WZ44, 2013 WY, 2013 WX44, 2013 WX43, 2013 WW45, 2013 WT45, 2013 WT44, 2013 WT43, 2013 WR45, 2013 WR43, 2013 WH, 2013 VC10, 2013 TV135, 2013 TR132, 2013 BE19, 2006 CT
A06Mataro Obs. in Spain, 1 in MPEC 2013-X28 -- 9950
5682David Tholen's team on Mauna Kea in Hawaii, 1 in MPEC 2013-X28 -- 2013 VJ13
568_Marco Micheli on Mauna Kea in Hawaii, 1 in MPEC 2013-X29 -- C/2013 X1
G96Mt. Lemmon Survey (MLS) in Arizona, 3 in MPECs 2013-X28 & 2013-X29 -- C/2013 X1, 2013 UV3, 2013 UT3
0892Oleksandr V. Shulga via Nikolaev Obs. in the Ukraine, 4 in MPEC 2013-X28 -- 2013 NJ, 2010 XZ67, 2010 CL19, 251346
X14Orbis Tertius Obs., 2 in MPEC 2013-X28 -- 2013 NJ, 1627
F51Pan-STARRS 1 (PS1) in Hawaii, 10 in MPECs 2013-X28 & 2013-X29 -- C/2013 X1, 2012 AS10, 2010 KB61, 1999 SK10, 376778, 373579, 20460, 185851, 11398, 1627
A53Peschiera del Garda Obs. in Italy, 2 in MPEC 2013-X28 -- 2010 CL19, 377097
D03Rantiga Obs., 1 in MPEC 2013-X28 -- 377097
291Spacewatch 1.8m telescope in Arizona, 2 in MPEC 2013-X28 -- 2013 WT67, 2013 WT43
926Tenagra II Obs. in Arizona, 5 in MPEC 2013-X28 -- 2013 WY44, 2013 WW45, 2013 WU45, 2013 WS67, 1997 WB21
A48Verona Obs. in Italy, 2 in MPEC 2013-X28 -- 2013 NJ, 2010 CL19
Q621Hidetaka Sato in Japan via iTelescope Obs. Siding Spring in New South Wales, 1 in MPEC 2013-X29 -- C/2013 X1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 6 December '13

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
2013 WT67JPL Sentry2315R E M O V E DJPL: Risk listing removed at 2300 UTC.
2013 WS67JPL Sentry2234R E M O V E DJPL: Risk listing removed at 2203 UTC.
2013 WZ44JPL Sentry2315211118.2e-07-6.67-6.670JPL: "Analysis based on 35 observations spanning 7.9160 days (2013-Nov-28.411 to 2013-Dec-06.32702)." Diameter approximately 0.025 km. from mean, weighted H=25.6.
2013 WX44JPL Sentry2234207113.0e-07-6.92-6.920JPL: "Analysis based on 28 observations spanning 8.8479 days (2013-Nov-27.50384 to 2013-Dec-06.35175)." Diameter approximately 0.024 km. from mean, weighted H=25.7.
2013 WT43JPL Sentry2315R E M O V E DJPL: Risk listing removed at 2256 UTC.
2013 VJ13JPL Sentry22342099-210439.3e-07-5.55-5.820JPL: "Analysis based on 47 observations spanning 23.257 days (2013-Nov-10.13475 to 2013-Dec-03.392126)." Diameter approximately 0.060 km. from mean, weighted H=23.8.

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 6 December '13

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

2315Noted that JPL Sentry has removed 2013 WT43 as an impact risk - see above
Noted that JPL Sentry has removed 2013 WT67 as an impact risk - see above
Noted that JPL Sentry has updated its 2013 WZ44 risk assessment - see above
2234Noted that JPL Sentry has updated its 2013 VJ13 risk assessment - see above
Noted that JPL Sentry has removed 2013 WS67 as an impact risk - see above
Noted that JPL Sentry has updated its 2013 WX44 risk assessment - see above
1758Updated Traffic Report
1755Grabbed MPEC 2013-X28 - Daily Orbit Update - see above
Grabbed MPEC 2013-X29 - Comet C/2013 X1 (Panstarrs) - see above