Contents  on 17 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 17 December '12

Seven objects reported inside ten LD

Seven asteroids are reported within ten lunar distances (LD) of our planet today. Inside Earth's Hill sphere, radar target intruder 2012 XB112 is outbound from 2.41 to 3.32 LD and three objects exit the sphere: 2012 XP134 passes from 3.01 to 4.88 LD, risk-listed intruder 2012 XL134 from 3.09 to 5.29 LD, and risk-listed 2012 XM16 from 3.14 to 4.56 LD.

Further out, 2012 XH112 is outbound from 4.57 to 7.66 LD and 2012 XN134 from 7.30 to 8.61 LD, while radar target 2012 XM55 is inbound from 5.30 to 4.79 LD.

Coming our way next, 2012 XP55 arrives inside ten LD on December 26th.

This report was generated at 1625 UTC with follow-up in today's DOU MPEC for 2012 XP134 and 2012 XH112 as well as departed objects 2012 XO134, 2012 XJ134, 2012 XJ112, 2012 XP2, and 2012 XH, plus distant 2011 LT17.


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.

NEOCP Activity  on 17 December '12

The MPC's NEO Confirmation Page has 5 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had five objects listed. Of these, three were "one nighters." So far The Tracking News has counted a total of nine 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 17 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-Y06 - "12:47 UT" - 2012 XM145


<< DOU on 17 Dec. '12 >>  MPEC 2012-Y05 - "06:04 UT" - Daily Orbit Update


MPEC 2012-Y04 - "01:58 UT" - 2009 DZ42

Observers  on 17 December '12

Eighteen observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 12 in MPEC 2012-Y05 -- 2012 XK16, 2012 XH, 2012 XE17, 2012 XC55, 2012 WK4, 2012 VM82, 2012 VJ6, 2012 SA22, 2012 MB7, 2003 YS17, 2003 YJ, 338049
300Bisei Spaceguard Center in Japan, 1 in MPEC 2012-Y05 -- 2012 XE133
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 29 in MPECs 2012-Y05 & 2012-Y06 -- 2012 XZ132, 2012 XR93, 2012 XR134, 2012 XQ93, 2012 XQ55, 2012 XP2, 2012 XO134, 2012 XM145, 2012 XK16, 2012 XJ134, 2012 XJ112, 2012 XH55, 2012 XH133, 2012 XG133, 2012 XF17, 2012 XE112, 2012 XD55, 2012 XD133, 2012 XD112, 2012 XC55, 2012 XC133, 2012 XA133, 2012 XA, 2011 LT17, 2006 DY, 2002 XZ38, 289227, 277039, 242216
J04ESA Optical Ground Station (ESA OGS) in the Canary Islands, 4 in MPECs 2012-Y04 & 2012-Y05 -- 2012 XT93, 2012 XK112, 2012 XG, 2009 DZ42
J95Great Shefford Obs. in England, 3 in MPECs 2012-Y05 & 2012-Y06 -- 2012 XM145, 2012 XM134, 2012 XE133
704LINEAR in New Mexico, 1 in MPEC 2012-Y06 -- 2012 XM145
5682David Tholen's team on Mauna Kea in Hawaii, 5 in MPEC 2012-Y05 -- 2012 XH133, 2012 XH112, 2012 XF133, 2012 XE133, 2012 VE46
213Montcabre Obs. in Spain, 1 in MPEC 2012-Y05 -- 4179
C91Montevenere Obs., 3 in MPEC 2012-Y05 -- 345705, 323179, 18882
J47Nazaret Obs. in Spain, 1 in MPEC 2012-Y05 -- 4179
J43Oukaimeden Obs. in Morocco, 1 in MPEC 2012-Y05 -- 329614
H45Petit Jean Mtn. South Obs. in Arkansas, 1 in MPEC 2012-Y05 -- 2012 QF49
D90`Kevin Hills in England via RAS Obs. Moorook in South Australia, 1 in MPEC 2012-Y06 -- 2012 XM145
C48Sayn Solar Obs. in Russia, 1 in MPEC 2012-Y05 -- 2012 XP134
204Schiaparelli Obs. in Italy, 1 in MPEC 2012-Y06 -- 2012 XM145
G25Sherbrooke Obs., 1 in MPEC 2012-Y05 -- 4179
587Sormano Obs. in Italy, 1 in MPEC 2012-Y05 -- 2012 XJ112
I42Westport Obs. in Massachusetts, 1 in MPEC 2012-Y05 -- 2012 TA219
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 17 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.
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 XM134JPL Sentry16212050-208347.3e-08-5.90-6.180JPL: "Analysis based on 23 observations spanning 3.7683 days (2012-Dec-13.17577 to 2012-Dec-16.94405)." Diameter approximately 0.110 km. from mean, weighted H=22.5.
NEODyS16212062-206211.04e-10-8.84-8.840NEODyS: "Based on 23 optical observations (of which 0 are rejected as outliers) from 2012-12-13.177 to 2012-12-16.945."
2012 XH133NEODyS1621R E M O V E D-
JPL Sentry1621R E M O V E DJPL: Risk listing removed at 1000 UTC.
2012 XG133JPL Sentry1621R E M O V E DJPL: Risk listing removed at 0951 UTC.
2012 XF133NEODyS1621R E M O V E D-
JPL Sentry1621R E M O V E DJPL: Risk listing removed at 1031 UTC.
2012 XE133JPL Sentry16212088-209121.5e-08-7.36-7.440JPL: "Analysis based on 66 observations spanning 4.4937 days (2012-Dec-12.43361 to 2012-Dec-16.92728)." Diameter approximately 0.067 km. from mean, weighted H=23.5.
NEODyS16212083-209129.87e-09-7.52-7.790NEODyS: "Based on 66 optical observations (of which 0 are rejected as outliers) from 2012-12-12.434 to 2012-12-16.928."
2012 XH112NEODyS1621R E M O V E D-
2012 XHNEODyS16212065-206511.54e-07-7.53-7.530NEODyS: "Based on 33 optical observations (of which 0 are rejected as outliers) from 2012-12-03.179 to 2012-12-13.522."
JPL Sentry1621R E M O V E DJPL: Risk listing removed at 0957 UTC.
2005 TM173JPL Sentry04472013-21101328.3e-07-5.50-6.310JPL: "Analysis based on 6 observations spanning 1.9467 days (2005-Oct-09.20072 to 2005-Oct-11.14743)." Diameter approximately 0.051 km. from mean, weighted H=24.1.

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 17 December '12

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

1625Generated Traffic Report
1621Noted that JPL Sentry has updated its 2012 XE133 risk assessment - see above
Noted that NEODyS has updated its 2012 XE133 risk assessment - see above
Noted that JPL Sentry has removed 2012 XF133 as an impact risk - see above
Noted that NEODyS has removed 2012 XF133 as an impact risk - see above
Noted that JPL Sentry has removed 2012 XG133 as an impact risk - see above
Noted that JPL Sentry has removed 2012 XH as an impact risk - see above
Noted that NEODyS has updated its 2012 XH risk assessment - see above
Noted that NEODyS has removed 2012 XH112 as an impact risk - see above
Noted that JPL Sentry has removed 2012 XH133 as an impact risk - see above
Noted that NEODyS has removed 2012 XH133 as an impact risk - see above
Noted that JPL Sentry has updated its 2012 XM134 risk assessment - see above
Noted that NEODyS has updated its 2012 XM134 risk assessment - see above
Grabbed MPEC 2012-Y05 - Daily Orbit Update - see above
Grabbed MPEC 2012-Y06 - 2012 XM145 - see above
0447Noted that JPL Sentry has updated its 2005 TM173 risk assessment - see above
0200Grabbed MPEC 2012-Y04 - 2009 DZ42 - see above