Contour spacecraft fragments from Spacewatch 1.8m 
telescope. (c)Copyright 2002 UA LPL Spacewatch Proj.

Five years ago today the NASA Contour mission to comet 2P/Encke fired up its kick rocket to boost out of Earth orbit and was never heard from again. The next day Spacewatch published this image from its 1.8-meter telescope, showing "two objects ... near one of the predicted positions of the Contour spacecraft" at a little more than one lunar distance from Earth and separated by about 460 km. Another piece may also have been located much further away. See A/CC's chronicle of these events. ©Copyright 2002 The Spacewatch Project, Univ. Ariz. LPL.


Contents  on 15 August '07

Resources:

The latest news: framed access (best), RSS news feed (flags updates), or redirection - Note: A/CC has a main Web site and a backup site.

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 this year 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.

Minor-Object News  on 15 August '07

Minor-Object Science  on 15 August '07

NEOCP Activity  on 15 August '07

The MPC's NEO Confirmation Page has 1 listing: 1 new

When last checked at 2305 UTC today, the Minor Planet Center's NEO discovery Confirmation Page (NEOCP) had one new listing. This was a "one nighter." So far Major News has counted a total of seven objects listed on the NEOCP at some point today.

To learn how observers use the NEOCP, see Suno Observatory's Practical guide on how to observe NEOCP object.

New MPECs  on 15 August '07

Minor Planet Electronic Circulars

As of last check at 2305 UTC, there have been three MPECs issued today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


MPEC 2007-P57 - "21:26 UT" - 2007 PF28


MPEC 2007-P56 - "11:30 UT" - 2007 PV27


<< DOU on 15 Aug. '07 >>  MPEC 2007-P55 - "06:08 UT" - Daily Orbit Update

Observers  on 15 August '07

A total of 27 observing facilities appear in today's MPECs.

B03Alter Satzberg Obs. in Austria, 5 in MPECs 2007-P55 & 2007-P57 -- 2007 PF28, 2007 PR25, 2007 PS9, 2007 PQ9, 2007 PP9
H55Astronomical Research Obs. in Illinois, 2 in MPEC 2007-P55 -- 2007 PU11, 2004 XP14
300Bisei Spaceguard Center in Japan, 2 in MPEC 2007-P55 -- 2007 LR32, 1999 JU3
0952program code 2 via Crimean Astrophysical Obs. in the Ukraine, 1 in MPEC 2007-P55 -- 2007 PB8
151Eschenberg Obs. in Switzerland, 8 in MPEC 2007-P55 -- 2007 PE8, 2007 PF6, 2007 LR32, 2007 HE15, 2003 RX7, 2002 NN4, 145656, 86324
595Farra d'Isonzo Obs. in Italy, 1 in MPEC 2007-P57 -- 2007 PF28
143Gnosca Obs. in Switzerland, 1 in MPEC 2007-P55 -- 2007 PR25
442Gualba Obs. in Spain, 1 in MPEC 2007-P55 -- 16636
A17Guidestar Obs. in Germany, 1 in MPEC 2007-P55 -- 2007 PS9
355Hadano Obs. in Japan, 5 in MPEC 2007-P55 -- 2007 LR32, 2007 HE15, 2007 CK26, 2002 NN4, 1999 JU3
379Hamamatsu-Yuto Obs. in Japan, 3 in MPEC 2007-P55 -- 2007 LR32, 2007 DT103, 2007 CK26
240Herrenberg Obs. in Germany, 4 in MPEC 2007-P55 -- 2007 LR32, 2002 NN4, 145656, 87309
F84Hibiscus Obs. in Tahiti, 1 in MPEC 2007-P56 -- 2007 PV27
046Klet Obs. in the Czech Republic, 3 in MPEC 2007-P55 -- 2007 PA8, 2007 PE8, 2007 CK26
704LINEAR in New Mexico, 10 in MPECs 2007-P55 & 2007-P57 -- 2007 PF28, 2007 PU11, 2007 PE8, 2007 DT103, 2005 GO22, 2004 BE11, 2003 SW222, 86324, 54686, 2100
474Mt. John Obs. in New Zealand, 1 in MPEC 2007-P56 -- 2007 PV27
A24New Millennium Obs. in Italy, 4 in MPEC 2007-P55 -- 2004 ST9, 145656, 86324, 85275
A56Parma Obs. in Italy, 2 in MPEC 2007-P55 -- 2007 PA8, 2007 PB8
D29Purple Mtn. Obs. XuYi Station in China, 1 in MPEC 2007-P55 -- 2003 BB43
H06%E. Guido in Italy via RAS Obs. Mayhill in New Mexico, 2 in MPECs 2007-P55 & 2007-P56 -- 2007 PV27, 2007 PU11
H68Red Barn Obs. in Georgia, 1 in MPEC 2007-P55 -- 85275
473Remanzacco Obs. in Italy, 2 in MPECs 2007-P55 & 2007-P57 -- 2007 PF28, 2007 PR25
204Schiaparelli Obs. in Italy, 3 in MPECs 2007-P55 & 2007-P56 -- 2007 PV27, 2007 PS25, 2000 PN8
E12Siding Spring Survey in New South Wales, 3 in MPECs 2007-P55 & 2007-P56 -- 2007 PV27, 2007 PH25, 2007 FE1
147Suno Obs. in Italy, 1 in MPEC 2007-P55 -- 2007 PA8
194Tivoli Obs. in Namibia, 5 in MPECs 2007-P55 & 2007-P56 -- 2007 PV27, 2007 FV42, 2007 FK1, 2007 FE1, 2003 WM25
198Wildberg Obs. in Germany, 2 in MPEC 2007-P55 -- 2007 CK26, 2004 ST9

Impact Risk Monitoring  on 15 August '07

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2305 UTC)
See the CRT page for a list of all objects rated recently as risks.
Note that the time horizon for JPL is 100 years from today and for NEODyS is now 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.
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
2007 PV27JPL14182018-21071012.2e-05-2.16-2.470JPL: "Analysis based on 21 observations spanning .79374 days (2007-Aug-14.56587 to 2007-Aug-15.35961)." Diameter approximately 0.260 km. from mean, weighted H=20.5.
2007 PR25JPL1418209411.8e-08-5.91-5.910JPL #2 for the day: "Analysis based on 26 observations spanning 1.6639 days (2007-Aug-13.22063 to 2007-Aug-14.88457)." Diameter approximately 0.160 km. from mean, weighted H=21.6.
NEODyS1418206114.32e-09-6.23-6.230NEODyS: "Based on 26 optical observations (of which 0 are rejected as outliers) from 2007/08/13.221 to 2007/08/14.885."
2007 PA8JPL14182033-2104511.6e-07-2.25-2.810JPL: "Analysis based on 49 observations spanning 5.7317 days (2007-Aug-09.21035 to 2007-Aug-14.94203)." Diameter approximately 2.460 km. from mean, weighted H=15.7.
NEODyS14182018-2082207.76e-08-2.38-2.850NEODyS: "Based on 49 optical observations (of which 0 are rejected as outliers) from 2007/08/09.211 to 2007/08/14.943."

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 an 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" for more about this.

Chronology  on 15 August '07

Times are UTC for when the items were noted or added by Major News.

2159Grabbed MPEC 2007-P57 - 2007 PF28 - see above
2112Added link to news story, "Comet May Have Exploded Over North America 13,000 Years Ago"
1538Added MOS paper, "A discontinuity in the low-mass initial mass function" - see above
Added MOS paper, "Specific Angular Momentum of Extrasolar Planetary Systems" - see above
Added link to news story, "Meteors Past and Future"
Added link to news story, "Prairie Meteorite Search comes to Melfort"
1418Noted that JPL has updated its 2007 PA8 risk assessment - see above
Noted that NEODyS has updated its 2007 PA8 risk assessment - see above
Noted that JPL has updated its 2007 PR25 risk assessment - see above
Noted that JPL has posted 2007 PV27 as an impact risk - see above
Grabbed MPEC 2007-P55 - Daily Orbit Update - see above
1417Noted that NEODyS has posted 2007 PR25 as an impact risk - see above
Grabbed MPEC 2007-P56 - 2007 PV27 - see above
0134Noted that JPL has posted 2007 PR25 as an impact risk - see above