Contents  on 21 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 21 December '09

The MPC's NEO Confirmation Page is currently empty

The NEOCP is currently empty. There were six listings noted earlier today.

New MPECs  on 21 December '09

Minor Planet Electronic Circulars

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


MPEC 2009-Y40 - "19:06 UT" - Comet C/2009 Y2 (Kowalski)


MPEC 2009-Y39 - "16:51 UT" - 2006 WS195


MPEC 2009-Y38 - "15:19 UT" - 2009 YV6


MPEC 2009-Y37 - "15:11 UT" - 2009 YU6


MPEC 2009-Y36 - "15:07 UT" - 2009 YT6


MPEC 2009-Y35 - "15:03 UT" - 2009 YS6


<< DOU on 21 Dec. '09 >>  MPEC 2009-Y34 - "07:16 UT" - Daily Orbit Update

Observers  on 21 December '09

Eighteen observing facilities appear in today's MPECs.

CodeObserver / observatory
A74Bergen-Enkheim Obs. in Germany, 1 in MPEC 2009-Y34 -- 2009 XT6
300Bisei Spaceguard Center in Japan, 1 in MPEC 2009-Y40 -- C/2009 Y2
B20Carmelita Obs. in Spain, 2 in MPEC 2009-Y34 -- 2009 WX51, 3552
703Catalina Sky Survey (CSS) in Arizona, 6 in MPECs 2009-Y34 & 2009-Y40 -- C/2009 Y2, 2009 XD, 2009 NH, 2004 TB18, 5604, 3200
448Desert Moon Obs. in New Mexico, 6 in MPEC 2009-Y34 -- 2009 XL8, 2009 XF2, 2009 XB2, 2009 WG104, 2009 WE253, 2002 XC91
J95Great Shefford Obs. in England, 4 in MPECs 2009-Y36, 2009-Y37, 2009-Y38 & 2009-Y40 -- 2009 YV6, 2009 YU6, 2009 YT6, C/2009 Y2
704LINEAR in New Mexico, 4 in MPEC 2009-Y34 -- 177651, 11398, 5587, 1865
H01Magdalena Ridge Obs. (MRO) in New Mexico, 5 in MPECs 2009-Y34, 2009-Y35, 2009-Y36, 2009-Y37 & 2009-Y40 -- 2009 YU6, 2009 YT6, 2009 YS6, C/2009 Y2, 2009 XO2
568Mauna Kea in Hawaii, 1 in MPEC 2009-Y39 -- 2006 WS195
900Moriyama Obs. in Japan, 1 in MPEC 2009-Y40 -- C/2009 Y2
G96Mt. Lemmon Survey (MLS) in Arizona, 12 in MPECs 2009-Y34, 2009-Y35, 2009-Y36, 2009-Y37, 2009-Y38 & 2009-Y40 -- 2009 YV6, 2009 YU6, 2009 YT6, 2009 YS6, C/2009 Y2, 2009 WW25, 2009 WG54, 2009 WF, 2004 DC, 2002 WP, 85990, 8567
J93Mt. Tuffley Obs. in England, 4 in MPEC 2009-Y34 -- 2006 UR, 2002 WP, 159402, 433
A24New Millennium Obs. in Italy, 1 in MPEC 2009-Y40 -- C/2009 Y2
H23Pear Tree Obs. in Florida, 1 in MPEC 2009-Y34 -- 152560
H36Sandlot Obs. in Kansas, 2 in MPECs 2009-Y35 & 2009-Y37 -- 2009 YU6, 2009 YS6
204Schiaparelli Obs. in Italy, 7 in MPEC 2009-Y34 -- 2009 YG, 2009 XT6, 2009 XR2, 2009 XP2, 2009 XO2, 2009 XF2, 2009 WR6
291Spacewatch 1.8m telescope in Arizona, 13 in MPECs 2009-Y34, 2009-Y35 & 2009-Y36 -- 2009 YT6, 2009 YS6, 2009 YQ, 2009 YG, 2009 XT6, 2009 XO, 2009 WK6, 2009 WC11, 2009 UN, 2005 TO45, 2003 QA31, 2003 QA, 2002 XY38
I15Wishing Star Obs. in Rhode Island, 2 in MPEC 2009-Y34 -- 2009 WZ104, 2002 WP
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 21 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 YV6JPL Sentry16572012-2106274.1e-08-4.68-4.990JPL: "Analysis based on 11 observations spanning .59126 days (2009-Dec-20.38323 to 2009-Dec-20.97449)." Diameter approximately 0.260 km. from mean, weighted H=20.6.
2009 YQJPL Sentry1514R E M O V E DJPL: Risk listing removed at 1052 UTC.
NEODyS1514R E M O V E D-
2009 YGJPL Sentry15142033-2107191.8e-07-3.18-3.700JPL: "Analysis based on 33 observations spanning 3.0312 days (2009-Dec-17.42051 to 2009-Dec-20.45175)." Diameter approximately 0.826 km. from mean, weighted H=18.1.
NEODyS15142033-2084135.2e-08-3.54-3.820NEODyS: "Based on 33 optical observations (of which 0 are rejected as outliers) from 2009/12/17.421 to 2009/12/20.453."
2009 XT6NEODyS1514207114.83e-08-4.76-4.760NEODyS: "Based on 77 optical observations (of which 0 are rejected as outliers) from 2009/12/13.406 to 2009/12/20.305."
JPL Sentry1514R E M O V E D-
2009 XONEODyS15142028-204627.31e-08-4.36-4.380NEODyS: "Based on 94 optical observations (of which 0 are rejected as outliers) from 2009/12/09.153 to 2009/12/20.318."

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 21 December '09

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

2038Grabbed MPEC 2009-Y40 - Comet C/2009 Y2 (Kowalski) - see above
Noted that the NEOCP has become empty
1808Grabbed MPEC 2009-Y39 - 2006 WS195 - see above
1657Noted that JPL Sentry has posted 2009 YV6 as an impact risk - see above
1543Grabbed MPEC 2009-Y37 - 2009 YU6 - see above
Grabbed MPEC 2009-Y38 - 2009 YV6 - see above
1514Noted that NEODyS has updated its 2009 XO risk assessment - see above
Noted that JPL Sentry has removed 2009 XT6 as an impact risk - see above
Noted that NEODyS 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 JPL Sentry has removed 2009 YQ as an impact risk - see above
Noted that NEODyS has removed 2009 YQ as an impact risk - see above
Grabbed MPEC 2009-Y34 - Daily Orbit Update - see above
Grabbed MPEC 2009-Y35 - 2009 YS6 - see above
Grabbed MPEC 2009-Y36 - 2009 YT6 - see above