Contents  on 22 April '13

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 22 April '13

Two objects reported inside ten LD

Two asteroids are reported to be within ten lunar distances (LD) of Earth today. 2013 GH66 is outbound from 5.16 to 5.47 LD and 2013 GH23 from 7.92 to 9.79 LD. Coming to the neighborhood next, there are no known close approaches until late July.

This report was generated at 1459 UTC with follow-up in today's DOU MPEC for departed objects 2013 GH66 and 2013 FK.

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 22 April '13

The MPC's NEO Confirmation Page has 30 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 30 objects listed. Of these, eleven were "one nighters." So far The Tracking News has counted a total of 56 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 22 April '13

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 2013-H27 - "22:04 UT" - Comet C/2013 H1 (La Sagra)

<< DOU on 22 Apr. '13 >>  MPEC 2013-H26 - "06:04 UT" - Daily Orbit Update

Observers  on 22 April '13

A total of 23 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 11 in MPECs 2013-H26 & 2013-H27 -- C/2013 H1, 2013 GS66, 2013 GR38, 2013 GQ38, 2013 GE84, 2013 GC34, 2013 FX13, 2013 FT13, 2013 FQ10, 2013 AM60, 89958
300Bisei Spaceguard Center in Japan, 1 in MPEC 2013-H27 -- C/2013 H1
B96Brixiis Obs. in Belgium, 1 in MPEC 2013-H27 -- C/2013 H1
160Castelmartini Obs. in Italy, 3 in MPEC 2013-H26 -- 2009 SC15, 354952, 274855
703Catalina Sky Survey (CSS) in Arizona, 4 in MPECs 2013-H26 & 2013-H27 -- C/2013 H1, 2013 GC34, 2013 FY13, 54686
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 10 in MPEC 2013-H26 -- 2013 HR, 2013 GU79, 2013 GT79, 2013 GH84, 2013 GH, 2013 FK, 2013 EN126, 2007 DB56, 2005 JE46, 2002 KL3
448Desert Moon Obs. in New Mexico, 4 in MPEC 2013-H26 -- 2013 GY68, 2013 EU9, 2013 EL28, 2000 WL63
H15ISON-NM Obs. in New Mexico, 1 in MPEC 2013-H26 -- 7888
J87La Canada Obs. in Spain, 1 in MPEC 2013-H27 -- C/2013 H1
J75La Sagra Obs. in Spain, 1 in MPEC 2013-H27 -- C/2013 H1
H01Magdalena Ridge Obs. in New Mexico, 1 in MPEC 2013-H26 -- 2013 GH66
711McDonald Obs. in Texas, 1 in MPEC 2013-H27 -- C/2013 H1
G96Mt. Lemmon Survey (MLS) in Arizona, 4 in MPEC 2013-H26 -- 2012 HW1, 2011 MB2, 350462, 164206
C23Olmen Obs. in Belgium, 1 in MPEC 2013-H27 -- C/2013 H1
I41Palomar Transient Factory (PTF) in southern California, 2 in MPEC 2013-H26 -- 2006 HU30, 54686
F51Pan-STARRS 1 (PS1) in Hawaii, 6 in MPEC 2013-H26 -- 354952, 24761, 184990, 6050, 3988, 3757
H36Sandlot Obs. in Kansas, 1 in MPEC 2013-H27 -- C/2013 H1
J84South Obs. in England, 1 in MPEC 2013-H27 -- C/2013 H1
691Spacewatch 0.9m telescope in Arizona, 3 in MPEC 2013-H26 -- 2013 GY68, 2013 GV68, 2013 GQ38
291Spacewatch 1.8m telescope in Arizona, 11 in MPECs 2013-H26 & 2013-H27 -- C/2013 H1, 2013 GX79, 2013 GV79, 2013 GU79, 2013 GR66, 2013 GH84, 2013 GH66, 2013 GG69, 2013 GF69, 2013 GE84, 2013 FW13
718Wiggins Obs. in Utah, 1 in MPEC 2013-H27 -- C/2013 H1
H06iTelescope Obs. Mayhill in New Mexico, 1 in MPEC 2013-H27 -- C/2013 H1
H06`Erik Bryssinck in Belgium via iTelescope Obs. Mayhill in New Mexico, 1 in MPEC 2013-H27 -- C/2013 H1
H06|Hidetaka Sato in Japan via iTelescope Obs. Mayhill in New Mexico, 1 in MPEC 2013-H27 -- C/2013 H1
I89iTelescope Obs. Nerpio in Spain, 1 in MPEC 2013-H27 -- C/2013 H1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 22 April '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 GG69JPL Sentry14572030-205553.1e-08-4.05-4.100JPL: "Analysis based on 32 observations spanning 10.924 days (2013-Apr-10.43133 to 2013-Apr-21.35503)." Diameter approximately 0.610 km. from mean, weighted H=18.7.
2013 GF69JPL Sentry1457R E M O V E DJPL: Risk listing removed at 0951 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 22 April '13

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

2324Grabbed MPEC 2013-H27 - Comet C/2013 H1 (La Sagra) - see above
1459Generated Traffic Report
1457Noted that JPL Sentry has removed 2013 GF69 as an impact risk - see above
Noted that JPL Sentry has updated its 2013 GG69 risk assessment - see above
Grabbed MPEC 2013-H26 - Daily Orbit Update - see above