Contents  on 21 November '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 21 November '11

The MPC's NEO Confirmation Page has 5 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had five objects listed. Of these, one was a "one nighter." So far The Tracking News has counted a total of fourteen 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 21 November '11

Minor Planet Electronic Circulars

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

MPEC 2011-W33 - "20:36 UT" - 2011 WK5

MPEC 2011-W32 - "20:34 UT" - 2011 WH5

<< DOU on 21 Nov. '11 >>  MPEC 2011-W31 - "06:04 UT" - Daily Orbit Update

Observers  on 21 November '11

A total of 21 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 3 in MPECs 2011-W31 & 2011-W32 -- 2011 WH5, 2011 GA55, 36284
B96Brixiis Obs. in Belgium, 1 in MPEC 2011-W31 -- 2011 WV4
160Castelmartini Obs. in Italy, 6 in MPEC 2011-W31 -- 2011 WA, 302831, 219071, 209924, 163081, 7341
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 9 in MPEC 2011-W31 -- 2011 WQ4, 2011 WO4, 2011 WN2, 2011 WM2, 2011 WL2, 2011 WC, 2011 VP12, 2011 UU158, 2011 UA
106Crni Vrh Obs. in Slovenia, 1 in MPEC 2011-W31 -- 304088
C81Dolomites Obs. in Italy, 1 in MPEC 2011-W33 -- 2011 WK5
595Farra d'Isonzo Obs. in Italy, 1 in MPEC 2011-W33 -- 2011 WK5
157Frasso Sabino Obs. in Italy, 4 in MPEC 2011-W31 -- 2011 WC, 2011 WA, 2011 SO25, 2011 OL51
379Hamamatsu-Yuto Obs. in Japan, 6 in MPEC 2011-W31 -- 2011 SR69, 2011 SL102, 2011 LC19, 283460, 170502, 2201
B15Inastars Obs. in Germany, 1 in MPEC 2011-W31 -- 2011 WA
C32Ka-Dar Obs. TAU Station in Russia, 3 in MPEC 2011-W31 -- 2011 WS2, 2011 VV5, 2011 VU5
950.Ovidiu Vaduvescu via La Palma in the Canary Islands, 1 in MPEC 2011-W31 -- 2011 UA276
H01Magdalena Ridge Obs. in New Mexico, 1 in MPEC 2011-W32 -- 2011 WH5
G96Mt. Lemmon Survey in Arizona, 1 in MPEC 2011-W32 -- 2011 WH5
J69North Obs. in England, 1 in MPEC 2011-W31 -- 137671
F51Pan-STARRS 1 (PS1) in Hawaii, 8 in MPECs 2011-W31 & 2011-W33 -- 2011 WV4, 2011 WK5, 2011 UZ275, 302523, 283460, 16834, 154330, 4183
586Pic du Midi Obs. in France, 3 in MPECs 2011-W31 & 2011-W33 -- 2011 WV2, 2011 WQ4, 2011 WK5
461SZTE Asteroid Program in Hungary, 1 in MPEC 2011-W31 -- 2005 YU55
291Spacewatch 1.8m telescope in Arizona, 3 in MPEC 2011-W31 -- 2011 WW4, 2011 WQ2, 2011 UE305
I93St. Pardon de Conques Obs. in France, 2 in MPECs 2011-W31 & 2011-W33 -- 2011 WQ4, 2011 WK5
B18Terskol Obs. in Russia, 1 in MPEC 2011-W33 -- 2011 WK5
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 21 November '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 CLOMON2 risk pages.





Notes for Today's Latest Risk Assessments
2011 WW4JPL Sentry1557R E M O V E DJPL: Risk listing removed at 0848 UTC.
2011 WQ4JPL Sentry1557204813.6e-07-7.58-7.580JPL: "Analysis based on 44 observations spanning 2.8286 days (2011-Nov-18.27488 to 2011-Nov-21.10351)." Diameter approximately 0.011 km. from mean, weighted H=27.4.
2011 WL2JPL Sentry15572060-2106188.6e-06-3.25-3.420JPL: "Analysis based on 67 observations spanning 3.9675 days (2011-Nov-16.31883 to 2011-Nov-20.28631)." Diameter approximately 0.240 km. from mean, weighted H=20.7.
NEODyS15572060-2090154.96e-07-4.37-4.980NEODyS: "Based on 67 optical observations (of which 0 are rejected as outliers) from 2011-11-16.320 to 2011-11-20.287."
2011 UE305JPL Sentry15572107-210931.9e-06-4.19-4.230JPL: "Analysis based on 23 observations spanning 20.956 days (2011-Oct-30.46441 to 2011-Nov-20.4201)." Diameter approximately 0.170 km. from mean, weighted H=21.4.

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 November '11

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

2105Grabbed MPEC 2011-W32 - 2011 WH5 - see above
Grabbed MPEC 2011-W33 - 2011 WK5 - see above
1557Noted that JPL Sentry has updated its 2011 UE305 risk assessment - see above
Noted that JPL Sentry has updated its 2011 WL2 risk assessment - see above
Noted that NEODyS has updated its 2011 WL2 risk assessment - see above
Noted that JPL Sentry has reposted 2011 WQ4 as an impact risk - see above
Noted that JPL Sentry has removed 2011 WW4 as an impact risk - see above
Grabbed MPEC 2011-W31 - Daily Orbit Update - see above