Contents  on 24 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 24 March '13

Three objects reported inside ten LD

Three objects are reported to be inside ten lunar distances (LD) of our home world today. Within Earth's Hill sphere, 2013 FG comes its closest to Earth on this passage, reaching 3.77 LD at 0745 UT. More distantly, 2013 ES11 is outbound from 6.83 to 8.05 LD and radar target intruder 2013 EC20 leaves ten LD, passing from 9.53 to 10.16 LD.

2013 FD8, which we earlier reported was coming to ten LD today, is now calculated to enter our reporting "bubble" tomorrow, along with radar target 2013 FB8 and risk-listed 2013 EL89. The next known object headed our way is risk-listed 2010 GM23, which arrives inside ten LD on April 10th.

This report was generated at 1610 UTC with first follow-up for 2013 FG (adding 5.240 days to a one-day discovery arc) and 2013 FD8 (extending a 0.869-day arc by 2.962 days) in today's DOU MPEC along with observation of 2013 EL89 and 2013 ES11. This report was updated at 1812 UTC with revised distances data.

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 24 March '13

The MPC's NEO Confirmation Page has 8 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had eight objects listed. Of these, six were "one nighters." So far The Tracking News has counted a total of thirteen listings on the NEOCP today.

New MPECs  on 24 March '13

Minor Planet Electronic Circulars

As of last check at 2357 UTC, there have been two MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2013-F46 - "21:15 UT" - Comet C/2013 F1 (Boattini)

<< DOU on 24 Mar. '13 >>  MPEC 2013-F45 - "06:06 UT" - Daily Orbit Update

Observers  on 24 March '13

Nineteen observers appear in today's MPECs.

CodeObserver / observatory
E23Arcadia Obs. in New South Wales, 1 in MPEC 2013-F45 -- 2013 FD11
H21Astronomical Research Obs. Westfield in Illinois, 1 in MPEC 2013-F45 -- 2013 EW108
I56Beckman Obs. in Spain, 1 in MPEC 2013-F45 -- 22771
300Bisei Spaceguard Center in Japan, 1 in MPEC 2013-F46 -- C/2013 F1
703Catalina Sky Survey (CSS) in Arizona, 4 in MPECs 2013-F45 & 2013-F46 -- 2013 FG, C/2013 F1, 2012 TA219, 1981
958Dax Obs. in France, 1 in MPEC 2013-F46 -- C/2013 F1
448Desert Moon Obs. in New Mexico, 6 in MPEC 2013-F45 -- 2013 FD11, 2013 EV89, 2013 ER89, 2001 OG25, 152952, 143637
E89Geyserland Obs. in New Zealand, 1 in MPEC 2013-F45 -- 96315
711McDonald Obs. in Texas, 1 in MPEC 2013-F46 -- C/2013 F1
G96Mt. Lemmon Survey (MLS) in Arizona, 7 in MPECs 2013-F45 & 2013-F46 -- 2013 FD8, C/2013 F1, 2013 EP89, 2007 CN26, 2001 YT3, 152952, 11284
I41Palomar Transient Factory (PTF) in southern California, 4 in MPEC 2013-F45 -- 2007 CN26, 40267, 27346, 8567
K33San Defendente Obs., 2 in MPEC 2013-F45 -- 2013 FA8, 2013 EV108
204Schiaparelli Obs. in Italy, 10 in MPEC 2013-F45 -- 2013 FG, 2013 FA8, 2013 EV89, 2013 EV108, 2013 EU9, 2013 ES11, 2013 EM89, 2013 EL89, 2010 CE55, 2001 TA2
E12Siding Spring Survey (SSS) in New South Wales, 27 in MPEC 2013-F45 -- 2013 FX7, 2013 CL89, 2012 XH55, 2011 EB12, 2009 SC15, 2009 DK46, 2007 YX1, 2005 EF, 1999 HA2, 96315, 66008, 355770, 338176, 307161, 242216, 230111, 189173, 173561, 153219, 144861, 141447, 7888, 3554, 3199, 1685, 1580, 1036
691Spacewatch 0.9m telescope in Arizona, 2 in MPEC 2013-F45 -- 2013 EV89, 1917
291Spacewatch 1.8m telescope in Arizona, 9 in MPEC 2013-F45 -- 2013 FZ7, 2013 FQ10, 2013 FL9, 2013 FD8, 2013 FA8, 2013 EY89, 2013 EO126, 2013 EM20, 2013 BF18
I93St. Pardon de Conques Obs. in France, 1 in MPEC 2013-F46 -- C/2013 F1
718Wiggins Obs. in Utah, 1 in MPEC 2013-F46 -- C/2013 F1
H06*Rolando Ligustri in Italy via iTelescope Obs. Mayhill in New Mexico, 1 in MPEC 2013-F46 -- C/2013 F1
H06|Hidetaka Sato in Japan via iTelescope Obs. Mayhill in New Mexico, 1 in MPEC 2013-F46 -- C/2013 F1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 24 March '13

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2358 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 EL89JPL Sentry1606210217.5e-09-8.90-8.900JPL: "Analysis based on 46 observations spanning 7.9440 days (2013-Mar-14.25151 to 2013-Mar-22.19552)." Diameter approximately 0.022 km. from mean, weighted H=25.9.
NEODyS16062087-208711.24e-08-8.60-8.60NEODyS: "Based on 46 optical observations (of which 0 are rejected as outliers) from 2013-03-14.252 to 2013-03-22.196."

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 24 March '13

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

2306Grabbed MPEC 2013-F46 - Comet C/2013 F1 (Boattini) - see above
1610Generated Traffic Report
1606Noted that JPL Sentry has updated its 2013 EL89 risk assessment - see above
Noted that NEODyS has reposted 2013 EL89 as an impact risk - see above
Grabbed MPEC 2013-F45 - Daily Orbit Update - see above