Contents  on 24 December '13

Asteroid/Comet Connection (A/CC) Resources:

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Traffic Report  on 24 December '13

Two objects reported inside ten LD

There are one and maybe two visitors reported within ten lunar distances (LD) of our home world today. Newly announced tiny intruder 2013 YB (perhaps two meters wide) is leaving the Earth-Moon system, passing today from 0.97 to 3.02 LD after reaching 0.07 LD at 1250 UT yesterday, about eight hours after discovery.

Further out, 2011 YD29 is calculated with major uncertainty to be inbound from 9.3 to 8.2 LD.

This report was updated at 2318 UTC with already departed new discovery 2013 YD (MPEC). This report was previously updated at 1558 UTC to note follow-up in today's DOU MPEC for departed radar target 2013 NJ. Today's first traffic report was generated at 0053 UTC with the discovery announced late yesterday of 2013 YB.

Notes: Ten times the distance to the Moon (ten LD) has no astronomical significance but is a useful reporting boundary. 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 24 December '13

The MPC's NEO Confirmation Page has 23 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 23 objects listed. Of these, sixteen were "one nighters." So far The Tracking News has counted a total of 32 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 24 December '13

Minor Planet Electronic Circulars

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

MPEC 2013-Y29 - "21:24 UT" - 2013 YG

MPEC 2013-Y28 - "21:19 UT" - 2013 YF

MPEC 2013-Y27 - "21:12 UT" - 2013 YE

MPEC 2013-Y26 - "21:06 UT" - 2013 YD

MPEC 2013-Y25 - "21:00 UT" - 2013 YC

<< DOU on 24 Dec. '13 >>  MPEC 2013-Y24 - "14:02 UT" - Daily Orbit Update

MPEC 2013-Y23 - "02:13 UT" - 2013 WY67

Observers  on 24 December '13

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

CodeObserver / observatory
160Castelmartini Obs. in Italy, 3 in MPEC 2013-Y24 -- 2013 VD13, 251346, 153201
703Catalina Sky Survey (CSS) in Arizona, 5 in MPECs 2013-Y23, 2013-Y24 & 2013-Y26 -- 2013 YD, 2013 WY67, 2012 ER14, 2004 YR, 376729
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 18 in MPEC 2013-Y24 -- 2013 XY9, 2013 XV8, 2013 XA21, 2013 WF108, 2013 VF13, 2013 VC10, 2013 UH9, 2013 TS4, 2013 TH5, 2013 TE6, 2013 NJ, 2013 MH7, 2013 LW28, 2013 BZ45, 2012 FR62, 2011 SG5, 2003 CC11, 2001 RE8
B50Corner Obs. in Germany, 2 in MPECs 2013-Y24 & 2013-Y26 -- 2013 YD, 2013 UR3
958Dax Obs. in France, 1 in MPEC 2013-Y26 -- 2013 YD
448Desert Moon Obs. in New Mexico, 8 in MPECs 2013-Y24, 2013-Y25, 2013-Y26 & 2013-Y29 -- 2013 YG, 2013 YD, 2013 YC, 2008 WK32, 2002 XS40, 2000 ST20, 381564, 36236
C43Hoyerswerda Obs. in Germany, 1 in MPEC 2013-Y26 -- 2013 YD
C41MASTER-II Obs. Kislovodsk in Russia, 1 in MPEC 2013-Y24 -- 433
C94MASTER-II Obs. Tunka in Russia, 1 in MPEC 2013-Y24 -- 3200
5682David Tholen's team on Mauna Kea in Hawaii, 11 in MPEC 2013-Y24 -- 2013 XY21, 2013 XS3, 2013 XG4, 2013 XE22, 2013 WW44, 2013 WU44, 2013 WU43, 2013 WT44, 2013 WN67, 2013 WF108, 2013 VZ9
711McDonald Obs. in Texas, 5 in MPECs 2013-Y25, 2013-Y26, 2013-Y27, 2013-Y28 & 2013-Y29 -- 2013 YG, 2013 YF, 2013 YE, 2013 YD, 2013 YC
G96Mt. Lemmon Survey (MLS) in Arizona, 6 in MPECs 2013-Y24, 2013-Y25, 2013-Y26, 2013-Y27, 2013-Y28 & 2013-Y29 -- 2013 YG, 2013 YF, 2013 YE, 2013 YD, 2013 YC, 2013 XE22
644NEAT's Mt. Palomar telescope in southern California, 1 in MPEC 2013-Y23 -- 2013 WY67
A24New Millennium Obs. in Italy, 7 in MPEC 2013-Y24 -- 2010 XZ67, 55532, 361071, 251346, 21088, 162566, 9950
J43Oukaimeden Obs. in Morocco, 2 in MPEC 2013-Y24 -- 18109, 16834
I41Palomar Transient Factory (PTF) in southern California, 2 in MPEC 2013-Y24 -- 2013 XZ21, 2013 VD13
F51Pan-STARRS 1 in Hawaii, 1 in MPEC 2013-Y24 -- 262623
B74Santa Maria de Montmagastrell Obs. in Spain, 1 in MPEC 2013-Y26 -- 2013 YD
291Spacewatch 1.8m telescope in Arizona, 19 in MPECs 2013-Y24, 2013-Y25 & 2013-Y29 -- 2013 YG, 2013 YC, 2013 XG4, 2013 XE22, 2013 WW44, 2013 WU44, 2013 WU43, 2013 WT67, 2013 WL, 2013 TW135, 2013 TV144, 2013 TD4, 2013 QJ10, 2013 JM7, 2013 EY27, 2010 FH81, 2008 WN2, 2008 QS11, 1997 WQ23
926Tenagra II Obs. in Arizona, 1 in MPEC 2013-Y24 -- 85182
I89"program code '"' (11) via iTelescope Obs. Nerpio in Spain, 1 in MPEC 2013-Y26 -- 2013 YD
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 24 December '13

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
2013 YCJPL Sentry23592031-2091184.9e-07-3.91-4.250JPL: "Analysis based on 25 observations spanning 1.0963 days (2013-Dec-23.16077 to 2013-Dec-24.25708)." Diameter approximately 0.199 km. from mean, weighted H=21.2.
2013 YBJPL Sentry02112017-2038115.8e-05-6.76-6.910JPL: "Analysis based on 8 observations spanning .15956 days (2013-Dec-23.21048 to 2013-Dec-23.37004)." Diameter approximately 0.002 km. from mean, weighted H=31.4.

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 December '13

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

2359Noted that JPL Sentry has posted 2013 YC as an impact risk - see above
2318Updated Traffic Report
2136Grabbed MPEC 2013-Y25 - 2013 YC - see above
Grabbed MPEC 2013-Y26 - 2013 YD - see above
Grabbed MPEC 2013-Y27 - 2013 YE - see above
Grabbed MPEC 2013-Y28 - 2013 YF - see above
Grabbed MPEC 2013-Y29 - 2013 YG - see above
1557Grabbed MPEC 2013-Y24 - Daily Orbit Update - see above
0502Grabbed MPEC 2013-Y23 - 2013 WY67 - see above
0211Noted that JPL Sentry has posted 2013 YB as an impact risk - see above