Sunday11 January 200411:29pm MST2004-01-12 UTC 0629 back top next  

The Asteroid/Comet Connection's
daily news journal about
asteroids, comets, and meteors

Today's issue status: done, cover revised

Tiny asteroid 2004 AD was just beyond 10.5 lunar distances (LD) from Earth when discovered early Sunday, January 4th UT, by Bruce Koehn at LONEOS (dome photo courtesy of Lowell Observatory). Robert Hutsebaut closed out the confirmation process as the faint object crossed into Orion 24 hours later (circled image from Major News of the 8th). And, some 70 hours after discovery, Mike Nolan bounced an Arecibo radar signal off of 2004 AD out past 12 LD (antenna photo courtesy of Arecibo). Red dots show positions reported through last night (details below), and the yellow path runs to end of visibility February 8th.

Small objects – part 1/1 Major News for 11 Jan. 2004 back top next  
Small objects

With the full Moon, which makes seeing difficult objects even harder, there wasn't a lot of news about observing the smallest (H>22.0) near-Earth asteroids in the week following A/CC's last seven-day report. But there was a surprise precovery for 2003 WP25 (H=24.4), found in NEAT Mt. Palomar observations from 25 October 2002, and there was one discovery.

From Monday through this morning, a total of five new-found NEAs were announced, of which one has absolute magnitude H=24.2. That puts 2004 AD at about 50 meters/yards wide, but radar observation indicates it is more on the order of 15 meters wide — see A/CC's reports January 7th ("Radar news") and 8th.

Bruce Koehn at LONEOS discovered 2004 AD early on January 4th, and it was confirmed overnight by Observatorio Astronomico de Mallorca (OAM) and La Canada, Table Mountain, Tenagra II, and Sabino Canyon observatories, capped off by Robert Hutsebaut as explained with the Thursday's "cover" image.

Screen shot from EasySky showing
Earth's smallest neighbors 10 Jan. 2004.
All motion is toward top of the graphic,

2004 AD continued to be followed during 5 and 7-10 January by OAM and Siding Spring, Tenagra II, Powell, Great Shefford, Table Mountain, Consell, and Sormano observatories. (Siding Spring, Table Mountain, and Tenagra II each reported it twice.)

Other small NEAs observed were Earth co-orbital candidate 2002 AA29 [link|alt] (H=24.1), picked up by Tenagra II on January 6th, and 2003 YN107 (H=26.6), which was followed by Siding Spring 4-5 January. The Minor Planet Center has 2002 AA29 flagged for observations as "Very desirable between 2004 Feb. 5-Mar. 6." And two borderline objects were also tracked. 2003 WH166 (H=21.9) was observed on the 4th by Siding Spring, on the 5th by Pla D'Arguines Observatory, and early yesterday by Desert Moon Observatory, which then went on to also catch 2003 YQ1 (H=22.0).

Note: The pursuit of 2004 AD is illustrated on today's cover, of which unfortunately a version online for about 11 hours credited discovery to LINEAR instead of LONEOS.

News briefs – part 1/1 Major News for 11 Jan. 2004 back top next  
News briefs

Stardust:  In conveying local angles about NASA missions, including Stardust but mostly about Mars rover missions, two newspaper articles tell about some of the people further behind the scene. The Desert Dispatch reports today about the experience of relaying mission communications at the NASA/JPL Deep Space Network (DSN) Goldstone Station in southern California's Mojave Desert. And the Hattiesburg, Mississippi American today tells about making parachutes for the government, including for NASA's Stardust return capsule.

First amateur-discovered binary?
On January 3rd, Raoul Behrend told the Minor Planet Mailing list (MPML) about Main Belt object, 1089 Tama:

Photometric observations of the asteroid (1089) Tama, obtained by R. Roy, Blauvac, France, C. Rinner, Ottmasheim, France and P. Antonini, Bedoin, France, on three nights between 2003-12-24 and 2004-01-03, are compatible with the lightcurve of a sychronised binary system presenting mutual eclipses or occultations. 

A considerable discussion ensued about the data and analysis (see the lightcurve), whether it could also represent a single very elongated object, and what further evidence could help decide.

A day later, Alan Harris told the MPML that "photometric observations continue to show features very suggestive of a binary system," and noted that "the orbit plan is likely nearly perpendicular to the ecliptic, [so] we expect the eclipse/occultation events to evolve rapidly, and probably go away entirely within a month or two." He added, "this may be the first discovery of a binary completely and independently discovered by amateur observers" [emphasis added]. But now some professional help from the Hubble Space Telescope or ground-based adaptive-optics telescopes would be very nice.

Risk monitoring - part 1/1 Major News for 11 Jan. 2004 back top next  
Risk monitoring 11 Jan.

The Sunday Daily Orbit Update MPEC carries observations of 2003 YG118 from the 1.8m Vatican Advanced Technology Telescope (VATT) on Kitt Peak in Arizona yesterday morning, and last night from Crni Vrh Observatory in Slovenia, Sormano Observatory in Italy, and Pla D'Arguines Observatory in Spain. And today JPL slightly raised its risk ratings on a single impact solution in 2087 for this object, which is now estimated to be on the order of 1.4 km. (0.9 mile) wide.

Summary Risk Table - sources checked at 0626 UTC, 12 Jan




 2003 YG118JPL 1/112087-20871-2.98-2.98024.667
NEODyS 12/31R E M O V E D
VI = count of "virtual impactors" (impact solutions)
See A/CC's Consolidated Risk Tables for more and maybe
  newer details, and check the monitors' links for latest info.
Note that only objects recently in view are shown here.
Publisher information, privacy statement, and disclaimer
The contents and presentation of this page are © Copyright 2004 Columbine, Inc. - All Rights Reserved
Please report broken links or other problems with this page to <>.
Any mentioned trademarks are the property of their respective owners.
Do NOT copy or mirror this page, but you are welcome to link to it. All information here is subject to change.
Individuals may make "snapshot" copies for their own private non-commercial use.
Linking: A/CC's Major News via frame or redirection, via partial mirror frame or redirection, or via news feed or XML/RSS
Bookmarks: A/CC's Major News via frame or redirection –&– via alternate partial mirror site frame or redirection