Contents  on 17 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 17 December '09

The MPC's NEO Confirmation Page has 5 listings: 1 new, 4 updated

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had one new and four updated listings. Of these, four were "one nighters." The Tracking News counted a total of seven listings on the NEOCP at some point on this day.

New MPECs  on 17 December '09

Minor Planet Electronic Circulars

There were five MPECs posted this day from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


MPEC 2009-Y21 - "23:18 UT" - Comet P/2009 W1 = 1999 XO188 (Hill)


MPEC 2009-Y20 - "14:34 UT" - 2009 WE253


<< DOU on 17 Dec. '09 >>  MPEC 2009-Y19 - "07:10 UT" - Daily Orbit Update


MPEC 2009-Y18 - "03:45 UT" - 2009 AM15


MPEC 2009-Y17 - "00:09 UT" - Comet P/2003 CP7 = 2009 X1 (LINEAR-NEAT)

Observers  on 17 December '09

Nineteen observing facilities appeared in this day's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield (ARO Westfield) in Illinois, 5 in MPEC 2009-Y19 -- 2009 XT6, 2009 XG8, 2009 XC2, 2009 WR6, 2008 AB31
703Catalina Sky Survey (CSS) in Arizona, 6 in MPEC 2009-Y19 -- 2009 XV, 2009 KN4, 1985 WA, 35432, 177651, 5646
A77Chante-Perdrix Obs. in France, 1 in MPEC 2009-Y21 -- P/2009 W1
379Hamamatsu-Yuto Obs. in Japan, 7 in MPEC 2009-Y19 -- 2009 XR2, 2009 XD, 2009 UV18, 2006 UR, 2005 MC, 2002 XN14, 35396
704LINEAR in New Mexico, 15 in MPEC 2009-Y19 -- 2009 XO, 2009 WW25, 2009 WR6, 2009 WF, 2009 NA, 2009 MX6, 2002 WP, 22753, 217683, 162998, 5131, 4486, 4015, 1865, 1627
J75La Sagra Obs. in Spain, 1 in MPEC 2009-Y20 -- 2009 WE253
H01Magdalena Ridge Obs. (MRO) in New Mexico, 5 in MPECs 2009-Y19 & 2009-Y20 -- 2009 XT6, 2009 XJ8, 2009 XG8, 2009 XC2, 2009 WE253
5682David Tholen's team on Mauna Kea in Hawaii, 1 in MPEC 2009-Y18 -- 2009 AM15
932McCarthy Obs. in Connecticut, 4 in MPEC 2009-Y19 -- 2009 XD, 2009 WD11, 2009 CQ5, 2000 CO101
G96Mt. Lemmon Survey (MLS) in Arizona, 4 in MPECs 2009-Y19, 2009-Y20 & 2009-Y21 -- 2009 XG8, 2009 WE253, P/2009 W1, 162998
716Palmer Divide Obs. in Colorado, 1 in MPEC 2009-Y19 -- 2009 XR2
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 8 in MPEC 2009-Y19 -- 2009 XZ6, 2009 XV, 2009 XR2, 2009 XD, 2009 NA, 2006 UR, 2005 RQ6, 2002 XN14
H36Sandlot Obs. in Kansas, 1 in MPEC 2009-Y17 -- P/2009 X1
E12Siding Spring Survey in New South Wales, 1 in MPEC 2009-Y19 -- 2009 XO2
587Sormano Obs. in Italy, 1 in MPEC 2009-Y19 -- 2009 WX51
691Spacewatch 0.9m telescope in Arizona, 2 in MPEC 2009-Y19 -- 2009 RN, 2004 KD1
291Spacewatch 1.8m telescope in Arizona, 2 in MPEC 2009-Y19 -- 2009 XT6, 2009 UK
926Tenagra II Obs. in Arizona, 6 in MPEC 2009-Y19 -- 2009 XZ6, 2009 XT6, 2009 XP2, 2009 XO2, 2009 XC2, 2009 XB2
C00Velikie Luki Obs. in Russia, 3 in MPEC 2009-Y19 -- 2009 RN, 2006 UR, 2005 MC
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 17 December '09

Summary Risk Table for Risk Assessments Updated Today   (last checks: JPL at 2309 and NEODyS 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. 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 XJ8JPL Sentry1619R E M O V E DJPL: Risk listing removed at 0949 UTC.
2009 XG8JPL Sentry16192030-207453.0e-08-3.91-4.000JPL: "Analysis based on 29 observations spanning 2.1075 days (2009-Dec-15.11126 to 2009-Dec-17.21875)." Diameter approximately 0.540 km. from mean, weighted H=19.0.
NEODyS16192062-206531.51e-08-4.52-4.650NEODyS: "Based on 29 optical observations (of which 0 are rejected as outliers) from 2009/12/15.112 to 2009/12/17.220."
2009 XT6JPL Sentry16192037-207125.5e-07-3.62-3.700JPL: "Analysis based on 44 observations spanning 3.1390 days (2009-Dec-13.4056 to 2009-Dec-16.54458)." Diameter approximately 0.329 km. from mean, weighted H=20.1.
NEODyS16192037-207125.7e-07-3.60-3.690NEODyS: "Based on 44 optical observations (of which 0 are rejected as outliers) from 2009/12/13.406 to 2009/12/16.545."
2009 XC2JPL Sentry1619R E M O V E DJPL: Risk listing removed at 0949 UTC.
NEODyS1619R E M O V E D-
2009 XONEODyS16192036-207822.74e-09-5.90-5.900NEODyS: "Based on 79 optical observations (of which 0 are rejected as outliers) from 2009/12/09.153 to 2009/12/16.378."

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 17 December '09

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

2359Grabbed MPEC 2009-Y21 - Comet P/2009 W1 = 1999 XO188 (Hill) - see above
1620Grabbed MPEC 2009-Y19 - Daily Orbit Update - see above
Grabbed MPEC 2009-Y20 - 2009 WE253 - see above
1619Noted that JPL Sentry has removed 2009 XC2 as an impact risk - see above
Noted that NEODyS has removed 2009 XC2 as an impact risk - see above
Noted that JPL Sentry has updated its 2009 XG8 risk assessment - see above
Noted that NEODyS has posted 2009 XG8 as an impact risk - see above
Noted that JPL Sentry has removed 2009 XJ8 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 NEODyS has updated its 2009 XT6 risk assessment - see above
0526Grabbed MPEC 2009-Y18 - 2009 AM15 - see above
Noted that the NEOCP has become active
0036Grabbed MPEC 2009-Y17 - Comet P/2003 CP7 = 2009 X1 (LINEAR-NEAT) - see above