Contents  on 28 February '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 28 February '12

Three objects reported inside ten LD

Three objects are reported within ten lunar distances (LD) of Earth today. 2012 DS32 enters Earth's Hill sphere and, further out, risk-listed 2012 CS46 is departing, moving from 4.3 to 5.6 LD*, and 2012 DN31 is inbound from 9.45 to 8.67 LD.

On approach, 2012 DR32 arrives within ten LD on March 1st and 2008 EJ85 comes inside ten LD on March 4th.

This report was updated at 2359 UTC with (new) follow-up for 2012 DX13 in radar and, earlier, follow-up in today's DOU MPEC for 2012 DM32, 2012 DN31, and 2012 DA14, as well as distant 2001 SG286. This report was previously updated at 0434 and 1640 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 28 February '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 2358 UTC when the database was dated 28 Feb.

NEOCP Activity  on 28 February '12

The MPC's NEO Confirmation Page has 27 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 27 objects listed. Of these, twelve were "one nighters." So far The Tracking News has counted a total of 47 listings on the NEOCP today.

New MPECs  on 28 February '12

Minor Planet Electronic Circulars

As of last check at 2358 UTC, there have been seven MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

MPEC 2012-D99 - "21:00 UT" - Editorial Notice: The Deletion of 2012 DU32

MPEC 2012-D98 - "20:35 UT" - 2012 DY43

MPEC 2012-D97 - "20:33 UT" - 2012 DX43

MPEC 2012-D96 - "20:30 UT" - 2012 DW43

MPEC 2012-D95 - "20:28 UT" - 2012 DV43

MPEC 2012-D94 - "16:14 UT" - 2010 DB34

<< DOU on 28 Feb. '12 >>  MPEC 2012-D93 - "06:04 UT" - Daily Orbit Update

Observers  on 28 February '12

A total of 21 observers appear in today's MPECs.

CodeObserver / observatory
251Arecibo in Puerto Rico, 1 in radar -- 2012 DX13
H21Astronomical Research Obs. Westfield in Illinois, 14 in MPECs 2012-D93, 2012-D94, 2012-D95 & 2012-D97 -- 2012 DZ13, 2012 DX43, 2012 DV43, 2012 DQ32, 2012 DP32, 2012 DM32, 2012 DK4, 2012 DC28, 2012 CA21, 2012 BL86, 2010 DB34, 2005 OE3, 2001 SG286, 2001 NZ1
J51Atlante Obs. in the Canary Islands, 2 in MPEC 2012-D93 -- 192642, 3103
300Bisei Spaceguard Center in Japan, 3 in MPEC 2012-D93 -- 2012 DY32, 2012 DW32, 2012 DV32
703Catalina Sky Survey (CSS) in Arizona, 13 in MPEC 2012-D93 -- 2012 DJ31, 2012 BN11, 2012 BC20, 2010 SV3, 2004 FC32, 68267, 310402, 243298, 189008, 172722, 154269, 6053, 5587
J01Cielo Profundo Obs. in Spain, 1 in MPEC 2012-D93 -- 2012 DA14
C13Como Obs. in Italy, 1 in MPEC 2012-D93 -- 2012 DQ8
I17Cupillari Obs. in Pennsylvania, 1 in MPEC 2012-D93 -- 138524
G48Doc Greiner Research Obs. Rancho Hildalgo in New Mexico, 1 in MPEC 2012-D93 -- 2012 DN31
639Dresden Obs. in Germany, 2 in MPEC 2012-D93 -- 2012 CD29, 2012 BJ134
595Farra d'Isonzo Obs. in Italy, 1 in MPEC 2012-D93 -- 2012 CA55
F65%Tim Lister in southern California via Faulkes Telescope North in Hawaii, 3 in MPECs 2012-D93, 2012-D97 & 2012-D98 -- 2012 DY43, 2012 DX43, 2012 DA14
704LINEAR in New Mexico, 2 in MPEC 2012-D93 -- 154269, 152667
950.Ovidiu Vaduvescu via La Palma in the Canary Islands, 2 in MPEC 2012-D93 -- 2012 AC13, 2011 FR29
C01Lohrmann Obs. in Germany, 6 in MPEC 2012-D93 -- 2012 BJ134, 2004 FC32, 312942, 237805, 162038, 138524
5682David Tholen's team on Mauna Kea in Hawaii, 2 in MPECs 2012-D95 & 2012-D96 -- 2012 DW43, 2012 DV43
474Mt. John Obs. in New Zealand, 4 in MPEC 2012-D93 -- 2012 DS30, 2012 DP32, 2012 DO, 2012 BC124
F51Pan-STARRS 1 (PS1) in Hawaii, 15 in MPECs 2012-D93, 2012-D95, 2012-D96, 2012-D97 & 2012-D98 -- 2012 DY43, 2012 DX43, 2012 DW43, 2012 DV43, 2009 MC9, 2004 QZ2, 2003 HR32, 2002 CW46, 38086, 267221, 243298, 141765, 137802, 5324, 1863
691Spacewatch 0.9m telescope in Arizona, 7 in MPEC 2012-D93 -- 2012 DL14, 2004 QZ2, 96631, 276049, 267221, 163000, 137064
291Spacewatch 1.8m telescope in Arizona, 2 in MPEC 2012-D93 -- 2012 DN, 2012 BJ86
J08Zonalunar Obs. in Spain, 1 in MPEC 2012-D93 -- 2012 BT23
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 28 February '12

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL at 2358 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 DA33NEODyS16382050-209093.51e-10-7.65-8.350NEODyS: "Based on 11 optical observations (of which 0 are rejected as outliers) from 2012-02-26.382 to 2012-02-27.300."
2012 DY32JPL Sentry1638R E M O V E DJPL: Risk listing removed at 0942 UTC.
2012 DA14JPL Sentry20012020-21013044.2e-04-3.12-4.150JPL #2 for the day: "Analysis based on 49 observations spanning 5.4454 days (2012-Feb-23.03431 to 2012-Feb-28.47967)." Diameter approximately 0.045 km. from mean, weighted H=24.4.
NEODyS16382020-20903323.29e-04-3.09-3.910NEODyS: "Based on 37 optical observations (of which 2 are rejected as outliers) from 2012-02-23.029 to 2012-02-27.060."
2012 CA21JPL Sentry1638207315.1e-06-2.43-2.430JPL: "Analysis based on 87 observations spanning 14.918 days (2012-Feb-12.12022 to 2012-Feb-27.03779)." Diameter approximately 0.450 km. from mean, weighted H=19.4.
NEODyS16382073-207316.99e-09-5.30-5.30NEODyS: "Based on 87 optical observations (of which 3 are rejected as outliers) from 2012-02-12.121 to 2012-02-27.039."
2012 BJ86JPL Sentry1638211211.9e-07-5.26-5.260JPL: "Analysis based on 66 observations spanning 29.235 days (2012-Jan-29.10142 to 2012-Feb-27.33649)." Diameter approximately 0.160 km. from mean, weighted H=21.6.
2008 JD33JPL Sentry04322016-2095341.1e-08-8.49-9.010JPL: "Analysis based on 13 observations spanning .11183 days (2008-May-15.28689 to 2008-May-15.39872)." Diameter approximately 0.015 km. from mean, weighted H=27.3.

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 28 February '12

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

2359Updated Traffic Report
2358Noted Radar Astrometry database update - see above
2129Grabbed MPEC 2012-D99 - Editorial Notice: The Deletion of 2012 DU32 - see above
2100Grabbed MPEC 2012-D95 - 2012 DV43 - see above
Grabbed MPEC 2012-D96 - 2012 DW43 - see above
Grabbed MPEC 2012-D97 - 2012 DX43 - see above
Grabbed MPEC 2012-D98 - 2012 DY43 - see above
2001Noted that JPL Sentry has updated its 2012 DA14 risk assessment - see above
1638Noted that JPL Sentry has updated its 2012 BJ86 risk assessment - see above
Noted that JPL Sentry has updated its 2012 CA21 risk assessment - see above
Noted that NEODyS has updated its 2012 CA21 risk assessment - see above
Noted that JPL Sentry has updated its 2012 DA14 risk assessment - see above
Noted that NEODyS has updated its 2012 DA14 risk assessment - see above
Noted that NEODyS has posted 2012 DA33 as an impact risk - see above
Noted that JPL Sentry has removed 2012 DY32 as an impact risk - see above
Grabbed MPEC 2012-D93 - Daily Orbit Update - see above
Grabbed MPEC 2012-D94 - 2010 DB34 - see above
0432Noted that JPL Sentry has updated its 2008 JD33 risk assessment - see above