217 Eudora occultation path for 29 May 2011. 
Credit: Steve Preston.

A message today on the Minor Planet Mailing List (MPML) appealed for participation from observers on or to either side of tonight's 0630 UTC track for the star shadow of 217 Eudora that will span the U.S. An observation campaign is seeking to determine the shape of the Main Belter and also looking for accompanying satellites. Image credit: Steve Preston.

Contents  on 28 May '11


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.

NEOCP Activity  on 28 May '11

The MPC's NEO Confirmation Page has 61 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 61 objects listed. Of these, 29 were "one nighters." So far The Tracking News has counted a total of 88 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 28 May '11

Minor Planet Electronic Circulars

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

MPEC 2011-K40 - "20:37 UT" - 2011 KE15

MPEC 2011-K39 - "15:34 UT" - 2011 KC15

<< DOU on 28 May '11 >>  MPEC 2011-K38 - "07:06 UT" - Daily Orbit Update

MPEC 2011-K37 - "00:43 UT" - 2008 HE

Observers  on 28 May '11

Thirteen observers appear in today's MPECs.

CodeObserver / observatory
703Catalina Sky Survey (CSS) in Arizona, 8 in MPECs 2011-K38 & 2011-K39 -- 2011 KC15, 2011 HL7, 2006 GY2, 2005 TR15, 1998 KM3, 85490, 21374, 8567
807|Robert Holmes via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 3 in MPECs 2011-K38 & 2011-K39 -- 2011 KC15, 2011 HL7, 2011 CG2
H26Doc Greiner Research Obs. in Wisconsin, 1 in MPEC 2011-K38 -- 2011 HP
J04ESA Optical Ground Station in the Canary Islands, 1 in MPEC 2011-K38 -- 2011 KQ12
J95Great Shefford Obs. in England, 3 in MPECs 2011-K37 & 2011-K38 -- 2011 KG13, 2011 HP, 2008 HE
704LINEAR in New Mexico, 5 in MPEC 2011-K38 -- 2011 KN9, 2006 UQ217, 68348, 275714, 4954
950.Ovidiu Vaduvescu via La Palma in the Canary Islands, 1 in MPEC 2011-K38 -- 2008 UZ94
H01Magdalena Ridge Obs. in New Mexico, 1 in MPEC 2011-K39 -- 2011 KC15
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPECs 2011-K39 & 2011-K40 -- 2011 KE15, 2011 KC15
204Schiaparelli Obs. in Italy, 7 in MPECs 2011-K37 & 2011-K38 -- 2011 KG13, 2011 AO52, 2008 HE, 2008 AS28, 2007 PP6, 2007 LQ19, 274138
291Spacewatch 1.8m telescope in Arizona, 1 in MPEC 2011-K38 -- 2011 EF15
I93St. Pardon de Conques Obs. in France, 1 in MPEC 2011-K39 -- 2011 KC15
A92Urseanu Obs. in Romania, 2 in MPEC 2011-K38 -- 267494, 3288
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 28 May '11

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 CLOMON (backup) risk pages.





Notes for Today's Latest Risk Assessments
2011 KE15JPL Sentry23112013-2103409.7e-05-4.45-4.960JPL: "Analysis based on 11 observations spanning 2.0236 days (2011-May-26.26154 to 2011-May-28.28515)." Diameter approximately 0.014 km. from mean, weighted H=26.9.

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 28 May '11

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

2311Noted that JPL Sentry has posted 2011 KE15 as an impact risk - see above
2101Grabbed MPEC 2011-K40 - 2011 KE15 - see above
1545Grabbed MPEC 2011-K39 - 2011 KC15 - see above
1516Grabbed MPEC 2011-K38 - Daily Orbit Update - see above
0202Grabbed MPEC 2011-K37 - 2008 HE - see above