Contents  on 9 March '12

Asteroid/Comet Connection (A/CC) 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.

Traffic Report  on 9 March '12

Five objects reported inside ten LD

Five objects are reported moving inside ten lunar distances (LD) from Earth today. Within Earth's Hill sphere, radar target 2012 DH54 goes from 3.64 to 3.35 LD. Further away, risk-listed radar target 2012 DW60 travels from 5.18 to 4.12 LD, 2012 EA is heading out from 6.91 to 7.98 LD, 2012 EM1 is outbound, moving from 8.24 to 8.89 LD, and returned but unobserved 2008 EJ85 is calculated with some uncertainty to exit ten LD, passing from 9.6 to 10.2 LD*.

Next known on approach, 2007 HV4 arrives inside ten LD on April 14th.

This report was updated at 1420 UTC with follow-up in today's DOU MPEC for 2012 DW60, and earlier with follow-up for 2012 DH54 in radar. This report was previously updated at 0538 UTC.

Notes: Ten times the distance to the Moon (ten LD) has no astronomical significance but is a useful reporting boundary. Earth's Hill sphere (of gravitational influence) is estimated to extend out to around 3.89 LD. Distances are interpreted by A/CC from JPL Horizons data. "LD*" indicates some passage uncertainty. See also today's timeline, current sky chart and object details (alt-details), and ephemerides.

Radar Astrometry  on 9 March '12

Radar observation of one object

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

Data update noted at 0537 UTC when the database was dated 8 March

NEOCP Activity  on 9 March '12

The MPC's NEO Confirmation Page has 1 listing

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had one object listed.

New MPECs  on 9 March '12

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 2012-E44 - "12:09 UT" - 2012 DS85

<< DOU on 9 Mar. '12 >>  MPEC 2012-E43 - "06:01 UT" - Daily Orbit Update

Observers  on 9 March '12

Five observers appear in today's MPECs.

CodeObserver / observatory
251Arecibo in Puerto Rico, 1 in radar -- 2012 DH54
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 10 in MPEC 2012-E43 -- 2012 EN3, 2012 DW60, 2012 DW30, 2012 DQ8, 2012 DO, 2012 BZ76, 2012 BC124, 2006 VQ13, 2002 KF4, 1999 JO8
A24New Millennium Obs. in Italy, 51 in MPEC 2012-E43 -- 2012 DQ8, 2012 CD29, 2012 BJ134, 2012 BC20, 2012 AA11, 2011 YV15, 2011 XO3, 2011 WV134, 2011 SL102, 2010 SV3, 2009 AV, 2008 PF1, 2006 AL8, 2004 QJ7, 85990, 85839, 32906, 311554, 306595, 302830, 29075, 263976, 24475, 237805, 21277, 21088, 184990, 163000, 162186, 154269, 152941, 143651, 142348, 141018, 138524, 138359, 138013, 137925, 101873, 9400, 8567, 6455, 6050, 4055, 3554, 3352, 3103, 1862, 1627, 1620, 1036
F51Pan-STARRS 1 (PS1) in Hawaii, 2 in MPEC 2012-E43 -- 2012 BN1, 2011 AG5
2905Richard P. Boyle via Vatican Advanced Technology Telescope in Arizona, 1 in MPEC 2012-E44 -- 2012 DS85
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 9 March '12

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
2012 DW60NEODyS14182065-2090478.69e-05-5.10-5.820NEODyS: "Based on 55 optical observations (of which 0 are rejected as outliers) from 2012-02-29.495 to 2012-03-08.263."
2011 AG5JPL Sentry17022040-204751.9e-03-1.03-1.031JPL #2 for the day: "Analysis based on 205 observations spanning 290.87 days (2010-Dec-04.530458 to 2011-Sep-21.398727)." Diameter approximately 0.140 km. from mean, weighted H=21.9.
NEODyS14182040-205391.94e-03-1.04-1.041NEODyS: "Based on 205 optical observations (of which 0 are rejected as outliers) from 2010-12-04.531 to 2011-09-21.399."

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 9 March '12

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

1702Noted that JPL Sentry has updated its 2011 AG5 risk assessment - see above
1420Updated Traffic Report
1418Noted that NEODyS has updated its 2011 AG5 risk assessment - see above
Noted that NEODyS has updated its 2012 DW60 risk assessment - see above
Grabbed MPEC 2012-E43 - Daily Orbit Update - see above
Grabbed MPEC 2012-E44 - 2012 DS85 - see above
0537Noted that JPL Sentry has updated its 2011 AG5 risk assessment - see above
Noted Radar Astrometry database update - see above