Contents  on 7 March '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 7 March '13

One object reported inside ten LD

One asteroid is reported traveling inside ten lunar distances (LD) of Earth today. Radar target 2013 ET is inbound from 7.14 to 4.75 LD. On approach next, 2007 EO88 (risk-listed radar target) is calculated with some uncertainty to arrive inside ten LD on March 15th, and newly announced risk-listed 2013 ES11 arrives on March 19th.

This report was updated at 1918 UTC with new discovery 2013 ES11 (MPEC). Today's first traffic report was generated at 1451 UTC with follow-up in today's DOU MPEC for 2013 ET and distant 136617 1994 CC.

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 7 March '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 2031 UTC when the database was dated 7 March

NEOCP Activity  on 7 March '13

The MPC's NEO Confirmation Page has 47 listings

When last checked at 2309 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 47 objects listed. Of these, 37 were "one nighters." The Tracking News counted a total of 63 listings on the NEOCP on this day.

New MPECs  on 7 March '13

Minor Planet Electronic Circulars

There were four MPECs posted this day from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2013-E28 - "19:55 UT" - 2011 HE103

MPEC 2013-E27 - "14:42 UT" - 2013 ET11

MPEC 2013-E26 - "14:37 UT" - 2013 ES11

<< DOU on 7 Mar. '13 >>  MPEC 2013-E25 - "06:04 UT" - Daily Orbit Update

Observers  on 7 March '13

A total of 20 observers appeared in this day's MPECs.

CodeObserver / observatory
E23Arcadia Obs. in New South Wales, 1 in MPEC 2013-E25 -- 2013 ET9
C60Argelander Institute for Astronomy Obs. in Germany, 1 in MPEC 2013-E25 -- 5645
300Bisei Spaceguard Center in Japan, 3 in MPECs 2013-E25 & 2013-E26 -- 2013 ES9, 2013 ES11, 2008 CA5
703Catalina Sky Survey in Arizona, 1 in MPEC 2013-E26 -- 2013 ES11
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 3 in MPEC 2013-E25 -- 2013 ET, 2013 ER4, 2013 EA
C73Galati Obs. in Romania, 3 in MPEC 2013-E25 -- 2013 ET, 3199, 1036
253Goldstone DSS-14 70m antenna in southern California, 1 in radar -- 2013 ET
W85LCOGT Cerro Tololo A in Chile, 1 in MPEC 2013-E25 -- 2013 ET
5682David Tholen's team on Mauna Kea in Hawaii, 1 in MPEC 2013-E27 -- 2013 ET11
711McDonald Obs. in Texas, 1 in MPEC 2013-E26 -- 2013 ES11
474Mt. John Obs. in New Zealand, 5 in MPEC 2013-E25 -- 2013 ET, 2013 ER, 2013 DM1, 2013 CN35, 2013 CL89
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPECs 2013-E25 & 2013-E26 -- 2013 ES11, 2013 CG129
2681program code 1 via New Horizons KBO Search, Magellan Clay Telescope in Chile, 1 in MPEC 2013-E28 -- 2011 HE103
2682program code 2 via New Horizons KBO Search, Magellan Clay Telescope in Chile, 1 in MPEC 2013-E28 -- 2011 HE103
F51Pan-STARRS 1 (PS1) in Hawaii, 11 in MPECs 2013-E25 & 2013-E27 -- 2013 ET11, 2008 AU26, 2006 WS1, 2004 FM17, 2001 YT3, 19764, 153267, 136617, 3360, 2368, 2101
H45Petit Jean Mtn. South Obs. in Arkansas, 1 in MPEC 2013-E25 -- 2009 AV
H36Sandlot Obs. in Kansas, 3 in MPECs 2013-E25, 2013-E26 & 2013-E27 -- 2013 ET11, 2013 ES11, 2013 CG129
E12Siding Spring Survey (SSS) in New South Wales, 3 in MPEC 2013-E25 -- 2013 EU9, 2013 ET9, 285263
291Spacewatch 1.8m telescope in Arizona, 3 in MPECs 2013-E25 & 2013-E26 -- 2013 ES11, 2010 DM56, 2009 WN
C36Starry Wanderer Obs. in Belarus, 1 in MPEC 2013-E25 -- 2013 ET
Q624program code 4 via iTelescope Obs. Siding Spring in New South Wales, 1 in MPEC 2013-E25 -- 2013 ET
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 7 March '13

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2309 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 ET11JPL Sentry1711207915.2e-10-9.54-9.540JPL: "Analysis based on 9 observations spanning 1.9294 days (2013-Mar-05.43112 to 2013-Mar-07.36049)." Diameter approximately 0.029 km. from mean, weighted H=25.3.
2013 ES11JPL Sentry17112042-209631.8e-09-7.85-8.020JPL: "Analysis based on 26 observations spanning 2.1148 days (2013-Mar-05.35562 to 2013-Mar-07.47038)." Diameter approximately 0.073 km. from mean, weighted H=23.3.

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 7 March '13

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

2031Grabbed MPEC 2013-E28 - 2011 HE103 - see above
Noted Radar Astrometry database update - see above
1918Updated Traffic Report
1711Noted that JPL Sentry has posted 2013 ES11 as an impact risk - see above
Noted that JPL Sentry has posted 2013 ET11 as an impact risk - see above
1447Grabbed MPEC 2013-E25 - Daily Orbit Update - see above
Grabbed MPEC 2013-E26 - 2013 ES11 - see above
Grabbed MPEC 2013-E27 - 2013 ET11 - see above