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

Today's issue status: done & updated

• Rosetta delay
• News briefs – comet news, Alaskan fireball, 2004 AS1 & IDP news
• Risk monitoring
  – NEODyS has posted 2004 DM44

Cover: For those who track NEOs, getting astrometric data to report to the Minor Planet Center is what matters, and pretty pictures are an occasional nice side result. This image stack is from Robert Hutsebaut's participation in confirming 2004 DM44, which JPL and NEODyS have now listed with impact solutions (see below). He did this observing at around 9:30am yesterday from home in Belgium with a rented telescope at New Mexico Skies.

Cancellation of this morning's 0736 UTC Rosetta launch attempt was announced at 86 minutes to go. An ESA statement, Rosetta Journal entry, and Arianespace news release and first and second Mission Updates, explain how, after yesterday's launch was weathered out, the core rocket's cryogenic fuel was removed. Before refueling began for today's attempt, a 10x15cm (4x6") piece of foam was discovered missing on the rocket's upper outside insulation (see at right). So it was decided to move the vehicle back to the Final Assembly Building for further inspection, and to replace the foam block, for which "the adhesive requires approximately 36 hours for its drying/curing process."

A New Scientist report today says the concern was that, with a piece of 5cm-thick (2") foam missing, atmospheric vapor could freeze into a small block of ice on the rocket's exposed surface, then separate during flight and cause damage. Space.com reports that removing the super-cold fuel may have led to the piece being popped off.

A/CC illustration from ESA-CNES-Arianespace-PSOVCSG photo

Arianespace says, "Resumption of the Flight 158 countdown is planned at the beginning of next week." Reuters and AFP report it will be Tuesday at the earliest. There is still plenty of time, with one launch opportunity per day until March 17th, after which the mission would have to stand down again to select and prepare for a new comet destination.

For a more personal take on living with these and last year's Rosetta delays, see a Sydney, Australia Morning Herald article dated tomorrow that tells about working in a "space-age town shaved from French Guiana's Amazon forest."

Comet news:  MPEC 2004-D44 today announces the discovery of distant comet C/2004 D1 (NEAT) (q=5.014 AU), and shows the first NEAT observations coming from its Mt. Palomar telescope early on the 17th. Eight other observatories did the follow-up during 18-23 and 26 February and this morning.

Alaskan fireball:  An Anchorage Daily News article today, "Meteor seen in Mat-Su sky," says the National Weather Service received two accounts of a meteor streaking "across the skies over the Susitna River Valley" at about 10:20pm Tuesday night, "producing a bluish fireball seen by people in Homer and Anchorage" that lasted "for six or seven seconds."

2004 AS1:  The Rocky Mountain News has an article today about local amateur astronomer Brian Warner's pivotal role in determining that there was nothing immediately threatening about a newly discovered object back in January that has since been designated 2004 AS1. See the Index for more about all that.

IDP news:  IDP = "Interplanetary dust particles"

“ Interstellar molecular clouds are the principal formation sites of organic matter in the Milky Way. A variety of simple molecules are produced in dense cold clouds. At such low temperatures, where the difference in chemical binding energy exceeds thermal energy, mass fractionation produces molecules with isotopic ratios that can be very different from molecules found on Earth. ”

According to news releases yesterday from Washington University in St. Louis (WUStL) and Lawrence Livermore National Laboratory (LLNL), researchers using the WUStL NanoSIMS probe have found the first organic material with an isotopic composition different than found on Earth "and in other parts of the Solar System." This, a new form of carbon found in a piece of dust collected in Earth's upper atmosphere, is believed to be older than the Solar System and an example of the kind of organic material that fell to Earth's surface before life began, and that continues falling today.

“ A lot of IDPs come from comets. It makes sense that organic material would be preserved in a very cold environment, such as where comets form at the edge of the Solar System. ”–Christine Floss, WUStL scientist

Risk monitoring 27 Feb.

Today NEODyS joined JPL in listing 2004 DM44 with impact solutions. See yesterday for details, and the "cover" above for a picture.

The MPC Status Page reported Wednesday that timing of Daily Orbit Update MPECs (DOUs) may be unpredictable while testing a new queuing system, and today's DOU was issued with a 1421 UT time stamp. It carries further observations of 2004 DM44 from yesterday morning from LINEAR in New Mexico.

Updates:  NEODyS has revised its 2004 DM44 assessment, further lowering its already low overall risk ratings. And JPL has now also revised its 2004 DM44 assessment, cutting its impact solution count from 32 to seven, and lowering overall risk ratings for this object. The MPC Last Observation page is showing that Powell Observatory in Kansas caught 2004 DV24 and 2004 DM44 this morning.