Contents  on 6 April '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 6 April '12

Four objects reported inside ten LD

Four objects are reported traveling inside ten lunar distances (LD) of Earth today. 2012 FA57 exits Earth's Hill sphere, moving from 2.53 to 4.47 LD. More distantly, 2012 FH58 is outbound from 5.87 to 7.70 LD and intruder 2012 FS35 from 8.00 to 8.77 LD, and radar target intruder 2012 EG5 departs from inside ten LD, passing from 8.68 to 10.56 LD.

Coming our way next, risk-listed 2012 GD arrives inside ten LD on April 8th and 2007 HV4 on April 14th.

This report was posted at 1636 UTC with follow-up from late March in today's DOU MPEC for 2012 FA57, 2012 FX35, 2012 FS35, and 2012 FP35.

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. Object distances are interpreted by A/CC from JPL Horizons data. See also current sky chart and object details (alt-details), ephemerides, and today's timeline.

NEOCP Activity  on 6 April '12

The MPC's NEO Confirmation Page has 18 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had eighteen objects listed. Of these, three were "one nighters." So far The Tracking News has counted a total of 25 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 6 April '12

Minor Planet Electronic Circulars

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

<< DOU on 6 Apr. '12 >>  MPEC 2012-G23 - "06:03 UT" - Daily Orbit Update

Observers  on 6 April '12

Four observers appear in today's MPEC.

CodeObserver / observatory
B88Bigmuskie Obs. in Italy, 2 in MPEC 2012-G23 -- 2012 FZ23, 2011 QD48
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 6 in MPEC 2012-G23 -- 2011 XE1, 2008 YT30, 2008 XE3, 2005 BC, 2002 QC7, 2001 OA14
850Cordell-Lorenz Obs. in Tennessee, 1 in MPEC 2012-G23 -- 2012 DX75
033Schwarzschild Obs. in Germany, 12 in MPEC 2012-G23 -- 2012 FZ44, 2012 FX35, 2012 FT23, 2012 FS35, 2012 FR35, 2012 FQ35, 2012 FP35, 2012 FF, 2012 FA57, 2012 EV14, 2012 ES14, 2012 EQ10
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 6 April '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 FA57JPL Sentry1631R E M O V E DJPL: Risk listing removed at 0850 UTC.

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 6 April '12

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

1636Posted Traffic Report
1631Noted that JPL Sentry has removed 2012 FA57 as an impact risk - see above
Grabbed MPEC 2012-G23 - Daily Orbit Update - see above