Contents  on 24 April '08


NOTE: The Tracking News and this Web site will be updating less often, and at sometimes irregular intervals, for the rest of April.

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 24 April '08

The MPC's NEO Confirmation Page is currently empty

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

New MPECs  on 24 April '08

Minor Planet Electronic Circulars

As of last check at 2357 UTC, there have been three MPECs issued today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2008-H24 - "16:00 UT" - 2008 HH

MPEC 2008-H23 - "14:35 UT" - 2008 HG

<< DOU on 24 Apr. '08 >>  MPEC 2008-H22 - "06:06 UT" - Daily Orbit Update

Observers  on 24 April '08

Fourteen observing facilities appear in today's MPECs.

CodeObserver / observatory
B03Alter Satzberg Obs. in Austria, 2 in MPEC 2008-H22 -- 2008 HE, 2008 GD110
H55Astronomical Research Obs. (ARO) in Illinois, 8 in MPEC 2008-H22 -- 2008 HE, 2008 GK2, 2008 GD1, 2008 GB110, 2008 FY6, 2008 EV5, 2008 EM9, 2008 AF4
J51Atlante Obs. in the Canary Islands, 6 in MPEC 2008-H22 -- 2008 GV3, 2008 FU6, 2008 DE, 2005 NB7, 154988, 3752
B11Cima Rest Obs. in Italy, 1 in MPEC 2008-H22 -- 2004 FN32
F653FTP education program via Faulkes Telescope North in Hawaii, 2 in MPECs 2008-H23 & 2008-H24 -- 2008 HH, 2008 HG
B32Gelenau Obs. in Germany, 1 in MPEC 2008-H22 -- 2004 CR2
J95Great Shefford Obs. in England, 4 in MPEC 2008-H22 -- 2008 HE, 2008 GF110, 2008 GD110, 2008 GC110
B19Iluro Obs. in Spain, 1 in MPEC 2008-H22 -- 2005 NB7
B15Inastars Obs. in Germany, 3 in MPEC 2008-H22 -- 2002 JC, 40267, 154988
5682David Tholen's team on Mauna Kea in Hawaii, 1 in MPEC 2008-H22 -- 2008 AF4
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPECs 2008-H23 & 2008-H24 -- 2008 HH, 2008 HG
854Sabino Canyon Obs. in Arizona, 1 in MPEC 2008-H23 -- 2008 HG
291Spacewatch 1.8m telescope in Arizona, 6 in MPECs 2008-H22 & 2008-H23 -- 2008 HG, 2008 GY3, 2008 GE110, 2008 GD1, 2008 FY6, 2008 FG
F85Tiki Obs. in Tahiti, 4 in MPEC 2008-H22 -- 2008 GC110, 2008 FN6, 2008 EJ1, 2005 UP156
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 24 April '08

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2356 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.
Note that the time horizon for JPL is 100 years from today and for NEODyS is usually the year 2090.
For the latest official risk assessments, and for explanations of the terminology, see the JPL NEO Program Sentry and NEODyS CLOMON (backup) risk pages.





Notes for Today's Latest Risk Assessments
2008 HHJPL Sentry21192021-2104187.3e-09-6.34-6.610JPL: "Analysis based on 14 observations spanning .27192 days (2008-Apr-24.30829 to 2008-Apr-24.58021)." Diameter approximately 0.148 km. from mean, weighted H=21.8.
2008 HGJPL Sentry21192035-209777.2e-09-7.34-7.500JPL: "Analysis based on 15 observations spanning .29900 days (2008-Apr-24.27646 to 2008-Apr-24.57546)." Diameter approximately 0.066 km. from mean, weighted H=23.5.
2008 HENEODyS1731207112.45e-11-6.66-6.660NEODyS: "Based on 50 optical observations (of which 0 are rejected as outliers) from 2008/04/18.139 to 2008/04/23.920."
JPL Sentry1048R E M O V E DJPL: Risk listing removed at 0920 UTC.
2008 AF4NEODyS1731208917.85e-09-5.76-5.760NEODyS: "Based on 604 optical observations (of which 4 are rejected as outliers) from 2008/01/10.397 to 2008/04/23.114."
JPL Sentry10482089-210065.7e-06-2.95-3.070JPL: "Analysis based on 600 observations spanning 103.72 days (2008-Jan-10.39652 to 2008-Apr-23.113051)." Diameter approximately 0.390 km. from mean, weighted H=19.7.

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 24 April '08

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

2119Noted that JPL Sentry has posted 2008 HG as an impact risk - see above
Noted that JPL Sentry has posted 2008 HH as an impact risk - see above
1731Noted that NEODyS has updated its 2008 AF4 risk assessment - see above
Noted that NEODyS has updated its 2008 HE risk assessment - see above
Grabbed MPEC 2008-H23 - 2008 HG - see above
Grabbed MPEC 2008-H24 - 2008 HH - see above
The NEOCP has become empty
1049Grabbed MPEC 2008-H22 - Daily Orbit Update - see above
1048Noted that JPL Sentry has updated its 2008 AF4 risk assessment - see above
Noted that JPL Sentry has removed 2008 HE as an impact risk - see above
The NEOCP has become active