Contents  on 23 September '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 September '13

One object reported inside ten LD

There is one object reported moving within ten lunar distances (LD) of our planet today. Within Earth's Hill sphere, tiny risk-listed intruder 2013 RZ53, possibly artificial, is outbound from 1.64 to 1.97 LD. It is in the day sky, thus not visible from ground-based telescopes. No other objects are known to be coming within ten LD until mid-November.

This report was generated at 1427 UTC with first follow-up in today's DOU MPEC for departed 2013 RT73 (boosting its observation arc from 2.64 to 9.00 days) and observation of departed 2013 RR43 from earlier this month plus tracking of distant radar target 152664 1998 FW4.

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. "Distant" is used to describe previous close-passers that are not coming inside ten LD on this passage or apparition. 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 September '13

The MPC's NEO Confirmation Page has 26 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 26 objects listed. Of these, nine were "one nighters." So far The Tracking News has counted a total of 33 listings on the NEOCP today.

New MPECs  on 23 September '13

Minor Planet Electronic Circulars

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

<< DOU on 23 Sept. '13 >>  MPEC 2013-S28 - "06:02 UT" - Daily Orbit Update

Observers  on 23 September '13

Sixteen observers appear in today's MPEC.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 15 in MPEC 2013-S28 -- 2013 RY5, 2013 RX80, 2013 RV9, 2013 RU9, 2013 RT73, 2013 RT43, 2013 RN9, 2013 RG74, 2013 RE6, 2013 RC32, 2013 RB6, 2013 RB30, 2013 QJ10, 2013 PV6, 2013 NX23
U82CS3 Palmer Divide Station in southern California, 1 in MPEC 2013-S28 -- 368664
160Castelmartini Obs. in Italy, 9 in MPEC 2013-S28 -- 2013 RX80, 2013 QN11, 2013 PX6, 2013 PV6, 2011 WU95, 52760, 251346, 152664, 6063
K37Cereseto Obs., 1 in MPEC 2013-S28 -- 2010 TN54
448Desert Moon Obs. in New Mexico, 9 in MPEC 2013-S28 -- 2013 RH74, 2009 DM1, 2003 OB4, 1996 RY3, 359592, 329437, 303262, 162273, 137126
G48Doc Greiner Research Obs. Rancho Hildalgo in New Mexico, 1 in MPEC 2013-S28 -- 2013 QJ10
J19El Maestrat Obs. in Spain, 3 in MPEC 2013-S28 -- 88710, 24445, 9950
246KLENOT in the Czech Republic, 3 in MPEC 2013-S28 -- 2013 RY5, 2013 RR9, 2013 QL10
560Madonna di Dossobuono Obs. in Italy, 1 in MPEC 2013-S28 -- 2013 SF
A13Naef Obs. in Switzerland, 2 in MPEC 2013-S28 -- 2013 RY5, 369986
F51Pan-STARRS 1 (PS1) in Hawaii, 5 in MPEC 2013-S28 -- 2011 BD40, 2009 CP5, 250697, 154276, 143678
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 8 in MPEC 2013-S28 -- 2013 QJ10, 2013 PX6, 2012 TS, 2010 TN54, 2005 EF, 2001 QC34, 369986, 250620
C95SATINO-1 in France, 1 in MPEC 2013-S28 -- 24445
204Schiaparelli Obs. in Italy, 13 in MPEC 2013-S28 -- 2013 RR43, 2013 RC6, 2013 QH11, 2013 PW6, 2013 PV6, 2013 PN43, 2013 NX23, 2009 WH106, 2009 CP5, 370061, 369454, 369452, 368664
G404program code 4 via Canary Islands Obs. in the Canary Islands, 1 in MPEC 2013-S28 -- 2013 SF
691Spacewatch 0.9m telescope in Arizona, 3 in MPEC 2013-S28 -- 2013 QH48, 2013 QH11, 2013 PA7
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 23 September '13

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS at 2359 and JPL at 2318 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 RG74NEODyS1420R E M O V E D-
2013 RR43JPL Sentry14202050-205721.5e-07-6.73-6.800JPL: "Analysis based on 22 observations spanning 3.8170 days (2013-Sep-09.46134 to 2013-Sep-13.278336)." Diameter approximately 0.027 km. from mean, weighted H=25.5.
NEODyS14202046-205731.97e-07-6.61-6.680NEODyS: "Based on 22 optical observations (of which 0 are rejected as outliers) from 2013-09-09.462 to 2013-09-13.279."
2013 RC32JPL Sentry1420208711.6e-06-4.64-4.640JPL: "Analysis based on 57 observations spanning 17.015 days (2013-Sep-05.42596 to 2013-Sep-22.440813)." Diameter approximately 0.140 km. from mean, weighted H=22.0.
NEODyS14202087-208717.94e-07-4.94-4.940NEODyS: "Based on 58 optical observations (of which 1 are rejected as outliers) from 2013-09-05.427 to 2013-09-22.442."

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 September '13

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

1427Generated Traffic Report
1420Noted that JPL Sentry has updated its 2013 RC32 risk assessment - see above
Noted that NEODyS has posted 2013 RC32 as an impact risk - see above
Noted that NEODyS has removed 2013 RG74 as an impact risk - see above
Noted that JPL Sentry has updated its 2013 RR43 risk assessment - see above
Noted that NEODyS has updated its 2013 RR43 risk assessment - see above
Grabbed MPEC 2013-S28 - Daily Orbit Update - see above