Contents  on 20 December '09

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.

NEOCP Activity  on 20 December '09

The MPC's NEO Confirmation Page has 6 listings: 6 updated

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had six updated listings. Of these, three were "one nighters." So far The Tracking News has counted a total of nine listings on the NEOCP at some point 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 20 December '09

Minor Planet Electronic Circulars

As of last check at 2358 UTC, there have been two MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


MPEC 2009-Y33 - "16:30 UT" - Comet C/2009 Y1 (Catalina)


<< DOU on 20 Dec. '09 >>  MPEC 2009-Y32 - "07:19 UT" - Daily Orbit Update

Observers  on 20 December '09

A total of 20 observing facilities appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield (ARO Westfield) in Illinois, 7 in MPEC 2009-Y32 -- 2009 WZ104, 2009 SM103, 2005 TY51, 2002 NW16, 2002 NP1, 1998 WT7, 162783
J51Atlante Obs. in the Canary Islands, 5 in MPEC 2009-Y32 -- 2009 XR2, 2009 XD, 2006 UR, 2005 MC, 217807
703Catalina Sky Survey (CSS) in Arizona, 7 in MPECs 2009-Y32 & 2009-Y33 -- C/2009 Y1, 2006 WR1, 16834, 143678, 137924, 137805, 433
J95Great Shefford Obs. in England, 2 in MPECs 2009-Y32 & 2009-Y33 -- 2009 YS, C/2009 Y1
442Gualba Obs. in Spain, 1 in MPEC 2009-Y32 -- 4015
704LINEAR in New Mexico, 1 in MPEC 2009-Y32 -- 163899
J38La Vara Obs. in Spain, 1 in MPEC 2009-Y32 -- 4015
H13Lenomiya Obs. in Arizona, 1 in MPEC 2009-Y32 -- 2009 XD
H01Magdalena Ridge Obs. (MRO) in New Mexico, 2 in MPECs 2009-Y32 & 2009-Y33 -- 2009 YR, C/2009 Y1
5682David Tholen's team on Mauna Kea in Hawaii, 2 in MPEC 2009-Y32 -- 2009 WO106, 2002 PN6
G96Mt. Lemmon Survey (MLS) in Arizona, 5 in MPECs 2009-Y32 & 2009-Y33 -- C/2009 Y1, 226219, 162168, 138971, 1627
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 7 in MPEC 2009-Y32 -- 2009 XD, 2009 XC2, 2009 UV18, 2009 ST19, 2005 MC, 2002 XN14, 2002 WP
H06RAS Obs. Mayhill in New Mexico, 1 in MPEC 2009-Y33 -- C/2009 Y1
939Rodeno Obs. in Spain, 1 in MPEC 2009-Y32 -- 4015
B74Santa Maria de Montmagastrell Obs. in Spain, 1 in MPEC 2009-Y32 -- 2009 XR2
204Schiaparelli Obs. in Italy, 1 in MPEC 2009-Y33 -- C/2009 Y1
E12Siding Spring Survey in New South Wales, 1 in MPEC 2009-Y32 -- 162181
291Spacewatch 1.8m telescope in Arizona, 19 in MPEC 2009-Y32 -- 2009 YR, 2009 YG, 2009 XV1, 2009 XT6, 2009 XQ1, 2009 XO, 2009 WN105, 2009 WL6, 2009 WK6, 2009 WH106, 2009 WH104, 2009 WC11, 2009 VY25, 2009 VT, 2009 SU19, 2007 DL41, 2006 YT13, 2006 SU131, 2002 PN6
C00Velikie Luki Obs. in Russia, 2 in MPEC 2009-Y32 -- 2006 UR, 2005 MC
H47Vicksburg Obs. in Mississippi, 2 in MPEC 2009-Y32 -- 2009 XD, 218863
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 20 December '09

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. Beginning Jan. 22nd, both are also posting impact solutions beyond 100 years for a few 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.
0000NNN000

Object

Risk
Monitor
When
Noted
UTC
0000T0000
Year
Range

VI
#
000NN00
Prob
Cum
T0000
PS
Cum
T0000
PS
Max

T
S


Notes for Today's Latest Risk Assessments
2009 YRJPL Sentry16502060-2107269.0e-06-6.84-7.280JPL #2 for the day: "Analysis based on 23 observations spanning .91307 days (2009-Dec-19.27429 to 2009-Dec-20.18736)." Diameter approximately 0.008 km. from mean, weighted H=28.0.
NEODyS16502060-208943.04e-06-7.21-7.340NEODyS: "Based on 23 optical observations (of which 0 are rejected as outliers) from 2009/12/19.275 to 2009/12/20.188."
2009 YQNEODyS16512015-2089578.48e-09-5.09-5.710NEODyS: "Based on 12 optical observations (of which 0 are rejected as outliers) from 2009/12/18.477 to 2009/12/19.544."
2009 YGJPL Sentry16502033-2107324.4e-07-2.79-3.380JPL: "Analysis based on 28 observations spanning 1.9986 days (2009-Dec-17.42051 to 2009-Dec-19.41908)." Diameter approximately 0.838 km. from mean, weighted H=18.0.
NEODyS16502033-2089121.61e-07-3.07-3.390NEODyS: "Based on 28 optical observations (of which 0 are rejected as outliers) from 2009/12/17.421 to 2009/12/19.420."
2009 XT6NEODyS1651207114.91e-07-3.75-3.750NEODyS: "Based on 67 optical observations (of which 0 are rejected as outliers) from 2009/12/13.406 to 2009/12/19.381."
JPL Sentry16502037-207124.7e-07-3.76-3.760JPL: "Analysis based on 67 observations spanning 5.9744 days (2009-Dec-13.4056 to 2009-Dec-19.38005)." Diameter approximately 0.320 km. from mean, weighted H=20.1.
2009 XONEODyS1650203811.89e-08-5.13-5.130NEODyS: "Based on 91 optical observations (of which 0 are rejected as outliers) from 2009/12/09.153 to 2009/12/19.369."
2009 WO106NEODyS1650R E M O V E D-
JPL Sentry1650R E M O V E DJPL: Risk listing removed at 1151 UTC.

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 20 December '09

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

1651Noted that NEODyS has updated its 2009 XT6 risk assessment - see above
Grabbed MPEC 2009-Y32 - Daily Orbit Update - see above
1650Noted that JPL Sentry has removed 2009 WO106 as an impact risk - see above
Noted that NEODyS has removed 2009 WO106 as an impact risk - see above
Noted that NEODyS has updated its 2009 XO risk assessment - see above
Noted that JPL Sentry has updated its 2009 XT6 risk assessment - see above
Noted that JPL Sentry has updated its 2009 YG risk assessment - see above
Noted that NEODyS has updated its 2009 YG risk assessment - see above
Noted that NEODyS has posted 2009 YQ as an impact risk - see above
Noted that JPL Sentry has updated its 2009 YR risk assessment - see above
Noted that NEODyS has posted 2009 YR as an impact risk - see above
Grabbed MPEC 2009-Y33 - Comet C/2009 Y1 (Catalina) - see above
0017Noted that JPL Sentry has posted 2009 YR as an impact risk - see above