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

Today's issue status: done, updated 3x

• News briefs – surprise flyby, New Horizons, Deep Impact, Rosetta + new comet C/2004 B1 (LINEAR)
• Risk monitoring – JPL & NEODyS have removed 2004 BA75 + JPL has posted 2004 BE68, 2004 BG86, 2004 BL86, & 2004 BZ74

Cover image: Main Belt asteroid 68 Leto is seen along with galaxy NGC 3628 in this 60-second exposure from December 20th when Robert Hutsebaut (see Major News Index) was working on his first batch of observations for the Minor Planet Center with a robotic Rent-a-scope 0.3m telescope at New Mexico Skies Observatory (more about that). He has never been to New Mexico, or to the U.S., and does his observing via the Internet from his home in Belgium.

Surprise flyby:  Francesco Manca at Sormano Observatory (see Closest Approaches and Small Asteroids lists) notes that 2004 BK86 will fly past Earth tomorrow at about 1.7 lunar distances. This Tunguska-class object, estimated to be roughly 25 meters/yards wide (H=25.4), was discovered yesterday morning by LINEAR in New Mexico and confirmed this morning by the Catalina Sky Survey (CSS) in Arizona, then announced in MPEC 2004-B79.

Deep Impact:  The Deep Impact mission's new January newsletter includes brief comments about Stardust results at comet 81P/Wild 2, an interview with telemetry engineer Felicia Sanders, and a report about a University of Texas at El Paso student CCD camera project for use on the JPL Table Mountain 1.2m telescope to make spectroscopic observations during the comet 9P/Tempel 1 encounter.

New Horizons:  Space.com last night reported ahead of next week's NASA budget release that the New Horizons "mission to Pluto remains funded."

Comet news:  IAUC 8279 last night announced comet C/2004 B1 (LINEAR), discovered by LINEAR in New Mexico early yesterday, and also found in observations from NEAT's telescope on Haleakala in Hawaii from the previous morning. Follow-up observation from Jim Young at JPL's Table Mountain Observatory in southern California found it to have a coma. MPEC 2004-B73 from last night has the observation details and orbital elements. The preliminary calculation has perihelion beyond the orbit of Mars at 2.152 AU on 9 May 2006 on a retrograde (i=123.3°) parabolic path.

Rosetta:  Arianspace Flight 158 is scheduled to roll out on February 24th and leave at 0716 UTC on the 26th with the Rosetta comet orbiter and lander. An Arianespace mission update yesterday told about topping off Rosetta's fuel and that "final integration" of the Ariane 5 launcher "is proceeding." An earlier update said the launch campaign had resumed on January 19th at Kourou in French Guiana, in South America, following a break for the holidays.

Risk monitoring 31 Jan.

JPL has posted 2004 BG86 with a single impact solution. It was announced in MPEC 2004-B77 today as discovered Wednesday morning by LINEAR in New Mexico, which also caught it the next morning, and was confirmed yesterday morning by Table Mountain Observatory in southern California and this morning by Desert Moon Observatory in New Mexico. JPL puts its diameter at roughly 750 meters/yards.

The Saturday Daily Orbit Update MPEC (DOU) has observations of 2004 BA75 with the Spacewatch 1.8m telescope in Arizona from early yesterday and this morning, and today both NEODyS and JPL removed all impact solutions for this small object.

The DOU has a set of observations of 2004 BE68 from LINEAR from yesterday morning, and today NEODyS slightly raised its risk ratings for this object and increased its impact solution count by six. 2004 BN41 was observed early yesterday with the Spacewatch 1.8m telescope, and today JPL very slightly lowered its risk assessment while adding a second

impact solution for this object, which it now estimates to be roughly 20 meters/yards wide. And LINEAR observed 2004 BZ74 yesterday morning. Today NEODyS slightly raised its risk ratings for this object while cutting its solution count from 146 to 44.

more Risk monitoring >>

<< continued from part 1

2213 UTC update:  JPL has posted 2004 BL86, which was announced today in MPEC 2004-B80 as discovered yesterday by LINEAR and confirmed today by CINEOS in Italy and Sabino Canyon Observatory in Arizona. Its width is on the order of 680 meters.

0355 UTC update:  JPL has joined NEODyS in posting 2004 BZ74. It went up after midnight UT but still Saturday in Pasadena.

Update:  On Saturday evening in Pasadena, JPL has now also joined NEODyS in posting 2004 BE68.