Contents  on 23 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 23 March '13

Three objects reported inside ten LD

Three asteroids are reported traveling inside ten lunar distances (LD) from Earth today. 2013 FG enters Earth's Hill sphere, going from 4.7 to 3.8 LD. Out further, 2013 ES11 is outbound from 6.31 to 6.83 LD and radar target intruder 2013 EC20 from 8.90 to 9.53 LD.

Up next, 2013 FD8 arrives inside ten LD tomorrow, and radar target 2013 FB8 and 2013 EL89 arrive the day after.

This report was generated at 1605 UTC with follow-up in today's DOU MPEC for 2013 FB8, 2013 EL89, and departed 2013 EE68.

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 23 March '13

The MPC's NEO Confirmation Page has 6 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had six objects listed. All of these were "one nighters." So far The Tracking News has counted a total of twelve listings on the NEOCP today.

New MPECs  on 23 March '13

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 2013-F44 - "10:43 UT" - 2013 FD11

MPEC 2013-F43 - "10:40 UT" - 2013 FC11

<< DOU on 23 Mar. '13 >>  MPEC 2013-F42 - "06:06 UT" - Daily Orbit Update

Observers  on 23 March '13

Fourteen observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 34 in MPECs 2013-F42, 2013-F43 & 2013-F44 -- 2013 FY7, 2013 FD11, 2013 FC11, 2013 FB8, 2013 FA8, 2013 EW27, 2013 EW108, 2013 EV108, 2013 ET9, 2013 ES, 2013 ER41, 2013 EQ4, 2013 EP89, 2013 EM89, 2013 EL89, 2013 EH89, 2013 EH68, 2013 EE68, 2013 EC68, 2013 EC28, 2013 CK89, 2013 AU76, 2012 VO6, 2012 QF49, 2009 WL1, 2008 HW1, 2007 YV29, 2001 OG25, 1995 FJ, 99942, 210012, 141447, 137158, 11054
300Bisei Spaceguard Center in Japan, 1 in MPEC 2013-F44 -- 2013 FD11
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 2 in MPECs 2013-F42 & 2013-F44 -- 2013 FX7, 2013 FD11
807~program code "~" (34) via Cerro Tololo Inter-American Obs. in Chile, 1 in MPEC 2013-F42 -- 2013 FB8
821Cordoba Obs. Bosque Alegre Station in Argentina, 1 in MPEC 2013-F44 -- 2013 FD11
K20Danastro Obs., 1 in MPEC 2013-F42 -- 7888
I48El Catalejo Obs. in Argentina, 1 in MPEC 2013-F44 -- 2013 FD11
130Lumezzane Obs. in Italy, 5 in MPEC 2013-F42 -- 2005 EM30, 11284, 7480, 5828, 2329
711McDonald Obs. in Texas, 9 in MPECs 2013-F42, 2013-F43 & 2013-F44 -- 2013 FZ7, 2013 FD11, 2013 FC11, 2013 FA8, 2013 ES89, 2013 EM20, 2007 TY18, 338176, 206910
F51Pan-STARRS 1 (PS1) in Hawaii, 2 in MPECs 2013-F43 & 2013-F44 -- 2013 FD11, 2013 FC11
W71Rand II Obs., 2 in MPEC 2013-F42 -- 335746, 214869
D90`Kevin Hills in England via RAS Obs. Moorook in South Australia, 2 in MPECs 2013-F42 & 2013-F44 -- 2013 FQ10, 2013 FD11
204Schiaparelli Obs. in Italy, 1 in MPEC 2013-F44 -- 2013 FD11
291Spacewatch 1.8m telescope in Arizona, 4 in MPEC 2013-F42 -- 2013 EW27, 2012 XO111, 2010 DM56, 2009 WO106
G56Walnut Creek Obs. in northern California, 1 in MPEC 2013-F42 -- 2013 FB8
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 23 March '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 FC11NEODyS15552025-209771.59e-10-5.95-6.530NEODyS: "Based on 10 optical observations (of which 0 are rejected as outliers) from 2013-03-19.485 to 2013-03-23.293."
2013 EL89JPL Sentry1555210216.4e-09-8.97-8.970JPL: "Analysis based on 43 observations spanning 7.9440 days (2013-Mar-14.25151 to 2013-Mar-22.19552)." Diameter approximately 0.023 km. from mean, weighted H=25.9.
2013 EH68NEODyS15552095-209527.47e-08-6.01-6.050NEODyS: "Based on 54 optical observations (of which 0 are rejected as outliers) from 2013-03-13.469 to 2013-03-20.289."

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 23 March '13

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

1605Generated Traffic Report
1555Noted that NEODyS has reposted 2013 EH68 as an impact risk - see above
Noted that JPL Sentry has updated its 2013 EL89 risk assessment - see above
Noted that NEODyS has posted 2013 FC11 as an impact risk - see above
Grabbed MPEC 2013-F42 - Daily Orbit Update - see above
Grabbed MPEC 2013-F43 - 2013 FC11 - see above
Grabbed MPEC 2013-F44 - 2013 FD11 - see above