Contents  on 8 March '13

Asteroid/Comet Connection (A/CC) Resources:

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Traffic Report  on 8 March '13

Three objects reported inside ten LD

Three objects are reported to be within a radius of ten lunar distances (LD) from our planet today. Newly announced intruder 2013 EC20 is inside the Earth-Moon system, moving from 0.87 to 0.40 LD, and two objects enter Earth's Hill sphere. Radar target 2013 ET comes in from 4.75 to 2.87 LD and newly discovered 2013 EN20 from 4.4 to 2.9 LD*.

Next known to be approaching, each with some uncertainty in calculation of timing and distance, are 2007 EO88, a risk-listed radar target that arrives inside ten LD on March 15th, and risk-listed 2013 ES11, which comes inside on March 19th.

This report was updated at 1715 UTC to note the discovery of 2013 EN20 (MPEC), observation of 2013 EC20, 2013 ET, and distant 136617 1994 CC in today's DOU MPEC, and radar observation of 2013 ET reported yesterday. Today's first traffic report was generated at 0604 UTC with new discovery 2013 EC20 (MPEC).

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. "LD*" indicates some uncertainty in time and distance. 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 8 March '13

The MPC's NEO Confirmation Page has 35 listings

When last checked at 2326 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 35 objects listed. Of these, 25 were "one nighters." So far The Tracking News has counted a total of 59 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 8 March '13

Minor Planet Electronic Circulars

As of last check at 2359 UTC, there have been seven MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2013-E35 - "20:50 UT" - Comet C/2013 E1 (McNaught)

MPEC 2013-E34 - "13:30 UT" - 2013 EO20

MPEC 2013-E33 - "13:25 UT" - 2013 EN20

MPEC 2013-E32 - "13:20 UT" - 2013 EM20

MPEC 2013-E31 - "12:14 UT" - 2000 BE19

<< DOU on 8 Mar. '13 >>  MPEC 2013-E30 - "06:05 UT" - Daily Orbit Update

MPEC 2013-E29 - "03:46 UT" - 2013 EC20

Observers  on 8 March '13

A total of 21 observers appear in today's MPECs.

CodeObserver / observatory
E23Arcadia Obs. in New South Wales, 1 in MPEC 2013-E35 -- C/2013 E1
H21Astronomical Research Obs. Westfield in Illinois, 3 in MPECs 2013-E31, 2013-E34 & 2013-E35 -- 2013 EO20, C/2013 E1, 2000 BE19
703Catalina Sky Survey (CSS) in Arizona, 7 in MPECs 2013-E29, 2013-E30 & 2013-E32 -- 2013 EM20, 2013 EC20, 2007 EF, 2005 EM30, 54686, 163696, 5131
448Desert Moon Obs. in New Mexico, 1 in MPEC 2013-E30 -- 143637
F658David Tholen's team in Hawaii via Faulkes Telescope North in Hawaii, 1 in MPEC 2013-E30 -- 99942
E104program code 4 via Faulkes Telescope South in New South Wales, 1 in MPEC 2013-E35 -- C/2013 E1
C73Galati Obs. in Romania, 2 in MPEC 2013-E30 -- 2009 UM3, 2062
C01Lohrmann Obs. in Germany, 1 in MPEC 2013-E30 -- 99942
568_Marco Micheli on Mauna Kea in Hawaii, 2 in MPECs 2013-E31 & 2013-E32 -- 2013 EM20, 2000 BE19
474Mt. John Obs. in New Zealand, 8 in MPEC 2013-E30 -- 2013 EU9, 2013 ER, 2013 DZ, 2013 DM1, 2013 CW35, 2013 CR35, 2013 CN35, 2012 GV11
G96Mt. Lemmon Survey (MLS) in Arizona, 6 in MPECs 2013-E30, 2013-E33, 2013-E34 & 2013-E35 -- 2013 EO20, 2013 EN20, C/2013 E1, 2004 RZ164, 39796, 3199
F51Pan-STARRS 1 (PS1) in Hawaii, 17 in MPECs 2013-E30, 2013-E31 & 2013-E32 -- 2013 EM20, 2013 CQ35, 2013 CP35, 2013 CN222, 2008 CR118, 2000 BE19, 87024, 52387, 40267, 333510, 198752, 162900, 162004, 137175, 136617, 108519, 9172
H23Pear Tree Obs. in Florida, 1 in MPEC 2013-E30 -- 2013 ET
D29Purple Mtn. Obs. Xuyi Station in China, 2 in MPEC 2013-E30 -- 2006 DY, 1917
H36Sandlot Obs. in Kansas, 2 in MPECs 2013-E31 & 2013-E32 -- 2013 EM20, 2000 BE19
033Schwarzschild Obs. in Germany, 10 in MPEC 2013-E30 -- 2013 ET, 2013 ES, 2013 ER, 2013 EQ4, 2013 EP, 2013 EA, 2013 DG, 2013 CN129, 2013 CK129, 2009 EM1
E12Siding Spring Survey in New South Wales, 1 in MPEC 2013-E35 -- C/2013 E1
291Spacewatch 1.8m telescope in Arizona, 5 in MPECs 2013-E30 & 2013-E33 -- 2013 ET, 2013 EN20, 2013 DQ9, 2013 AB32, 2012 UW68
C36Starry Wanderer Obs. in Belarus, 1 in MPEC 2013-E30 -- 2013 ET
H06|Hidetaka Sato in Japan via iTelescope Obs. Mayhill in New Mexico, 1 in MPEC 2013-E30 -- 8507
Q621program code 1 via iTelescope Obs. Siding Spring in New South Wales, 1 in MPEC 2013-E35 -- C/2013 E1
Q622program code 2 via iTelescope Obs. Siding Spring in New South Wales, 1 in MPEC 2013-E35 -- C/2013 E1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 8 March '13

Summary Risk Table for Risk Assessments Updated Today
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 EC20JPL Sentry15052092-210927.5e-07-8.27-8.340JPL #2 for the day: "Analysis based on 21 observations spanning .97709 days (2013-Mar-07.21579 to 2013-Mar-08.19288)." Diameter approximately 0.007 km. from mean, weighted H=28.5.
NEODyS15052108-210814.14e-08-9.59-9.590NEODyS: "Based on 21 optical observations (of which 0 are rejected as outliers) from 2013-03-07.217 to 2013-03-08.194."
2013 ET11NEODyS15052068-207922.95e-08-7.86-7.870NEODyS: "Based on 9 optical observations (of which 0 are rejected as outliers) from 2013-03-05.432 to 2013-03-07.361."
2013 ES11NEODyS15052054-206234.22e-09-7.57-7.890NEODyS: "Based on 26 optical observations (of which 0 are rejected as outliers) from 2013-03-05.356 to 2013-03-07.471."

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 8 March '13

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

2105Grabbed MPEC 2013-E35 - Comet C/2013 E1 (McNaught) - see above
1715Updated Traffic Report
1505Noted that JPL Sentry has updated its 2013 EC20 risk assessment - see above
Noted that NEODyS has posted 2013 EC20 as an impact risk - see above
Noted that NEODyS has posted 2013 ES11 as an impact risk - see above
Noted that NEODyS has posted 2013 ET11 as an impact risk - see above
Grabbed MPEC 2013-E30 - Daily Orbit Update - see above
Grabbed MPEC 2013-E31 - 2000 BE19 - see above
Grabbed MPEC 2013-E32 - 2013 EM20 - see above
Grabbed MPEC 2013-E33 - 2013 EN20 - see above
Grabbed MPEC 2013-E34 - 2013 EO20 - see above
0616Noted that JPL Sentry has posted 2013 EC20 as an impact risk - see above
0519Grabbed MPEC 2013-E29 - 2013 EC20 - see above