Arecibo radar April 2010 image of 2005 YU55
Credit: NASA/Cornell/Arecibo

Sometime between 1900 and 1930 UTC, the JPL Solar System Dynamics (SSD) Group Radar Astrometry database posted observations from today of inbound 2005 YU55 from Goldstone in southern California (see below). Refined ephemerides are available from SSD Horizons for when this intruder becomes visible to ground-based optical observers on November 8th. This image of the object is from Arecibo in April 2010. Radar imagery credit: NASA/Cornell/Arecibo.


Contents  on 4 November '11

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.

Radar Astrometry  on 4 November '11

Radar observation of two objects

The JPL Solar System Dynamics Group Radar Astrometry database has added or updated the following small-body radar observing work:


Data update noted at 1930 UTC when the database was dated 4 Nov.


Data update noted at 2239 UTC when the database was dated 4 Nov.

NEOCP Activity  on 4 November '11

The MPC's NEO Confirmation Page has 16 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had sixteen objects listed. Of these, six were "one nighters." So far The Tracking News has counted a total of eighteen listings on the NEOCP today.

New MPECs  on 4 November '11

Minor Planet Electronic Circulars

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


MPEC 2011-V18 - "17:36 UT" - 2011 VH5


<< DOU on 4 Nov. '11 >>  MPEC 2011-V17 - "06:06 UT" - Daily Orbit Update

Observers  on 4 November '11

Eighteen observers appear in today's MPECs.

CodeObserver / observatory
A50Andrushivka Obs. in the Ukraine, 1 in MPEC 2011-V17 -- 16816
H21Astronomical Research Obs. Westfield in Illinois, 5 in MPEC 2011-V17 -- 2011 US63, 2011 UM169, 2011 UD21, 2011 KP17, 2007 VH186
703Catalina Sky Survey (CSS) in Arizona, 7 in MPEC 2011-V17 -- 2011 UT91, 2011 UP63, 2004 XM130, 32906, 26760, 3553, 1620
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 9 in MPEC 2011-V17 -- 2011 UZ275, 2011 UZ255, 2011 UY255, 2011 UM169, 2011 UL147, 2011 UG256, 2011 UB276, 2011 UA276, 2011 UA193
821Cordoba Obs. Bosque Alegre Station in Argentina, 2 in MPEC 2011-V17 -- 2009 VO24, 2003 YJ
J04ESA Optical Ground Station (ESA OGS) in the Canary Islands, 2 in MPEC 2011-V17 -- 2001 UE5, 2201
253Goldstone DSS-14 70m antenna in southern California, 2 in radar -- 2011 LC19, 2005 YU55
379Hamamatsu-Yuto Obs. in Japan, 2 in MPEC 2011-V17 -- 2011 SR69, 2011 SL102
C32Ka-Dar Obs. TAU Station in Russia, 3 in MPEC 2011-V17 -- 24475, 154656, 154302
695]Mark Trueblood via Kitt Peak Natl. Obs. in Arizona, 1 in MPEC 2011-V17 -- 2008 QT3
046Klet Obs. in the Czech Republic, 10 in MPEC 2011-V17 -- 2011 UZ275, 2011 UU158, 2011 UU106, 2011 US63, 2011 UG256, 2011 TN9, 2011 SR69, 2011 RR12, 2011 PT1, 2008 UX
704LINEAR in New Mexico, 3 in MPEC 2011-V17 -- 2011 UU106, 85818, 4183
C01Lohrmann Obs. in Germany, 1 in MPEC 2011-V17 -- 2011 SR69
932McCarthy Obs. in Connecticut, 1 in MPEC 2011-V17 -- 2011 UL21
G96Mt. Lemmon Survey (MLS) in Arizona, 9 in MPECs 2011-V17 & 2011-V18 -- 2011 VH5, 2011 UW158, 2011 UU106, 2011 UJ169, 2011 SZ21, 2002 YB12, 67367, 173689, 137799
D90`Kevin Hills in England via RAS Obs. Moorook in South Australia, 2 in MPEC 2011-V17 -- 2011 UZ275, 2011 UB276
691Spacewatch 0.9m telescope in Arizona, 2 in MPEC 2011-V17 -- 136923, 12923
291Spacewatch 1.8m telescope in Arizona, 22 in MPECs 2011-V17 & 2011-V18 -- 2011 VH5, 2011 UY63, 2011 UY192, 2011 UX114, 2011 UW158, 2011 UW114, 2011 UV158, 2011 UU20, 2011 UU158, 2011 UU, 2011 UT91, 2011 US91, 2011 UM147, 2011 UL21, 2011 UK10, 2011 UH169, 2011 UF21, 2011 UE305, 2011 UB190, 2011 UA131, 2011 TA4, 2011 SD173
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 4 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.
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
2011 UE305JPL Sentry17302042-210963.7e-07-4.58-4.830JPL: "Analysis based on 17 observations spanning 4.0423 days (2011-Oct-30.46441 to 2011-Nov-03.50674)." Diameter approximately 0.179 km. from mean, weighted H=21.4.
NEODyS17302042-207751.8e-07-4.81-4.950NEODyS: "Based on 17 optical observations (of which 0 are rejected as outliers) from 2011-10-30.465 to 2011-11-03.508."
2011 UZ255JPL Sentry17302066-210541.3e-05-4.20-4.210JPL: "Analysis based on 51 observations spanning 3.7559 days (2011-Oct-30.44574 to 2011-Nov-03.20161)." Diameter approximately 0.069 km. from mean, weighted H=23.5.
NEODyS17302066-208971.2e-05-4.21-4.240NEODyS: "Based on 51 optical observations (of which 0 are rejected as outliers) from 2011-10-30.447 to 2011-11-03.202."
2011 UM169JPL Sentry17302100-2107195.4e-05-4.49-4.710JPL: "Analysis based on 39 observations spanning 6.7504 days (2011-Oct-27.37573 to 2011-Nov-03.12613)." Diameter approximately 0.033 km. from mean, weighted H=25.0.
2011 UW158JPL Sentry17302046-2111854.5e-05-2.02-2.351JPL: "Analysis based on 58 observations spanning 9.0645 days (2011-Oct-25.4186 to 2011-Nov-03.4831)." Diameter approximately 0.449 km. from mean, weighted H=19.4.
NEODyS17302046-208578.62e-06-2.66-2.750NEODyS: "Based on 58 optical observations (of which 2 are rejected as outliers) from 2011-10-25.419 to 2011-11-03.484."
2011 UL21NEODyS1730R E M O V E D-
JPL Sentry1730R E M O V E DJPL: Risk listing removed at 0851 UTC.
2011 UD21JPL Sentry1730210513.2e-06-7.72-7.720JPL: "Analysis based on 72 observations spanning 14.687 days (2011-Oct-18.42484 to 2011-Nov-02.111371)." Diameter approximately 0.007 km. from mean, weighted H=28.5.

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 4 November '11

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

2239Noted Radar Astrometry database update - see above
1930Noted Radar Astrometry database update - see above
1809Grabbed MPEC 2011-V18 - 2011 VH5 - see above
1730Noted that JPL Sentry has reposted 2011 UD21 as an impact risk - see above
Noted that JPL Sentry has updated its 2011 UE305 risk assessment - see above
Noted that NEODyS has updated its 2011 UE305 risk assessment - see above
Noted that JPL Sentry has removed 2011 UL21 as an impact risk - see above
Noted that NEODyS has removed 2011 UL21 as an impact risk - see above
Noted that JPL Sentry has updated its 2011 UM169 risk assessment - see above
Noted that JPL Sentry has updated its 2011 UW158 risk assessment - see above
Noted that NEODyS has updated its 2011 UW158 risk assessment - see above
Noted that JPL Sentry has updated its 2011 UZ255 risk assessment - see above
Noted that NEODyS has updated its 2011 UZ255 risk assessment - see above
Grabbed MPEC 2011-V17 - Daily Orbit Update - see above