Contents  on 20 February '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 20 February '13

Six objects reported inside ten LD

There are six objects reported inside ten lunar distances (LD) of Earth today, all of them moving away. In distance order, 2013 CW129 is outbound from 5.11 to 8.77 LD, radar target intruder 2012 DA14 from 5.88 to 7.26 LD, 2013 CZ87 from 7.12 to 7.55 LD, radar target 2013 BS45 from 7.29 to 7.81 LD, 2013 DB from 7.32 to 8.36 LD, and 2013 CE82 leaves ten LD, traveling from 8.23 to 10.82 LD.

On the list of objects known to be headed our way, risk-listed 2007 EO88 is next, arriving inside ten LD on March 15th.

This report was generated at 1511 UTC with follow-up in today's DOU MPEC for 2013 DP1, 2013 DB, 2013 CZ87, and 2012 DA14, plus departed objects 2013 DC1, risk-listed 2013 CL22, and intruder 2013 CY. And, since it wasn't pointed out in the previous traffic report, we should note here that radar observations were posted yesterday for 2013 BS45 and 2012 DA14.

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.

Radar Astrometry  on 20 February '13

Radar observation of one object

The JPL Solar System Dynamics Group Radar Astrometry database has added or updated the following small-body radar observing work:

Data update noted at 0137 UTC when the database was dated 19 Feb.

NEOCP Activity  on 20 February '13

The MPC's NEO Confirmation Page has 7 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had seven objects listed. Of these, three were "one nighters."

New MPECs  on 20 February '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.

<< DOU on 20 Feb. '13 >>  MPEC 2013-D42 - "06:04 UT" - Daily Orbit Update

MPEC 2013-D41 - "02:29 UT" - Comet C/2013 D1 (Holvorcem)

Observers  on 20 February '13

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

CodeObserver / observatory
C77Bernezzo Obs. in Italy, 3 in MPEC 2013-D42 -- 11405, 5828, 3752
703Catalina Sky Survey in Arizona, 1 in MPEC 2013-D42 -- 2012 SQ56
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 15 in MPEC 2013-D42 -- 2013 CX129, 2013 CK89, 2013 CK129, 2013 BE19, 2013 BC74, 2013 AU27, 2013 AT76, 2012 YN6, 2012 XC112, 2012 QQ50, 2012 QO10, 2010 CL19, 2009 CN5, 2002 XZ38, 2001 YT3
850Cordell-Lorenz Obs. in Tennessee, 2 in MPEC 2013-D42 -- 2012 TJ146, 10115
253Goldstone DSS-14 70m antenna in southern California, 1 in radar -- 4179
J95Great Shefford Obs. in England, 3 in MPEC 2013-D42 -- 2013 DG, 2013 DB, 2013 CZ87
W85LCOGT Cerro Tololo A in Chile, 3 in MPEC 2013-D42 -- 2013 DZ, 2013 DP1, 2013 DM1
J38La Vara Obs. in Spain, 1 in MPEC 2013-D42 -- 2012 DA14
C91Montevenere Obs., 3 in MPEC 2013-D42 -- 99942, 343098, 154347
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPEC 2013-D42 -- 2013 DC1, 229007
583Odessa-Mayaki Obs. in the Ukraine, 1 in MPEC 2013-D42 -- 3752
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 6 in MPEC 2013-D42 -- 2013 CT36, 2013 AU76, 2008 DG17, 1999 CT8, 99942, 4179
D29Purple Mtn. Obs. Xuyi Station in China, 2 in MPEC 2013-D42 -- 25916, 229007
B04Saint-Barthelemy Obs. in Italy, 1 in MPEC 2013-D42 -- 2012 DA14
H36Sandlot Obs. in Kansas, 2 in MPEC 2013-D42 -- 2013 DU, 2013 DA
691Spacewatch 0.9m telescope in Arizona, 2 in MPEC 2013-D42 -- 68278, 198752
291Spacewatch 1.8m telescope in Arizona, 3 in MPEC 2013-D42 -- 2013 CY, 2013 CL22, 2013 CK129
926Tenagra II Obs. in Arizona, 1 in MPEC 2013-D41 -- C/2013 D1
B51Vallauris Obs. in France, 1 in MPEC 2013-D42 -- 2012 DA14
H06iTelescope Obs. Mayhill in New Mexico, 1 in MPEC 2013-D42 -- 2012 DA14
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 20 February '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 CK129JPL Sentry1505207213.2e-08-6.07-6.070JPL: "Analysis based on 38 observations spanning 4.8436 days (2013-Feb-14.49468 to 2013-Feb-19.33827)." Diameter approximately 0.140 km. from mean, weighted H=22.0.
2013 CL22JPL Sentry1505206432.9e-06-5.47-5.700JPL: "Analysis based on 71 observations spanning 14.321 days (2013-Feb-05.05792 to 2013-Feb-19.37845)." Diameter approximately 0.039 km. from mean, weighted H=24.7.
NEODyS15052064-206421.08e-06-5.89-5.940NEODyS: "Based on 71 optical observations (of which 3 are rejected as outliers) from 2013-02-05.059 to 2013-02-19.379."
2013 CYJPL Sentry15052069-209874.1e-06-7.31-7.980JPL: "Analysis based on 80 observations spanning 18.061 days (2013-Feb-01.34874 to 2013-Feb-19.40959)." Diameter approximately 0.008 km. from mean, weighted H=28.2.
NEODyS15052072-209283.84e-06-7.33-7.960NEODyS: "Based on 80 optical observations (of which 0 are rejected as outliers) from 2013-02-01.350 to 2013-02-19.410."

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 20 February '13

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

1511Generated Traffic Report
1505Noted that JPL Sentry has updated its 2013 CK129 risk assessment - see above
Noted that JPL Sentry has updated its 2013 CL22 risk assessment - see above
Noted that NEODyS has updated its 2013 CL22 risk assessment - see above
Noted that JPL Sentry has updated its 2013 CY risk assessment - see above
Noted that NEODyS has updated its 2013 CY risk assessment - see above
Grabbed MPEC 2013-D42 - Daily Orbit Update - see above
0503Grabbed MPEC 2013-D41 - Comet C/2013 D1 (Holvorcem) - see above
0137Noted Radar Astrometry database update - see above