Friday9 January 20048:25pm MST2004-01-10 UTC 0325 back top next  
Stardust 81P/Wild 2 flyby

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


Today's issue status: done
yesterdayJanuarytomorrowIndex

Cover: Today's cover features a slightly reduced copy of R. Mark Elowitz's enhanced version of the photo NASA/JPL released Tuesday of the nucleus of comet 81P/Wild 2 [link|alt]. A very reduced copy of the fuzzier original release is inset at lower right. At upper left is A/CC's reworked version of a flyby animation posted yesterday on the Stardust mission home page. All original photo credits belong to NASA/JPL. See below for more information about these images.

Spanish fireball update – part 1/1 Major News for 9 Jan. 2004 back top next  

Spanish fireball update
By Marco Langbroek

There is a new piece of news on the Spanish fireball, with thanks to Oscar Rodriguez (Spain) and Jose Campos (Portugal)

Meteorite fragment found?

News has broken through Spanish news media that a possible small meteorite fragment "the size of a ping-pong ball" might have been found in Fuentes de Ropel in Zamora province. The fragment has been turned in to the Guardia Civil and handed over to scientists for analysis. The story in Spanish has pictures and a video [a3n.tv links are very temporary–Ed.].

From the pictures published, it is difficult to come to conclusive statements, but, nevertheless, what is shown somewhat resembles a meteorite, for as far as can be judged from these pictures. It will need examination by an expert to confirm, however, and I understand this is in progress. The recovery location (42.0N, 5.53W) is somewhat difficult to reconcile

with the Leon video, however, as it is to the southeast of Leon (see my report yesterday).

Thanks to Josep Trigo for a very informative link on the Spanish Photographic Meteor Network (SPMN) news page. Their report in Spanish, "Un superbolido sobrevuela Argelia, siendo registrado desde el sur de Espana," presents conclusions similar to what I wrote yesterday, placing the end of the trajectory on the border of Leon and Burgos departments, which is the same general area as I pointed out.


That report also shows, and links to a report about, a fireball seen over Spain on the 23rd of January last year, caught by an all-sky camera. It is seen flying past Orion and, "much brighter than the full Moon," lighting up cirrus clouds.–Ed.

News briefs – part 1/1 Major News for 9 Jan. 2004 back top next  
News briefs

SOHO news:  An ESA news release today explains "SOHO Keyhole Operations" and lists periods when SOHO will be closed for solar observation and comet discovery.

Cover info:  As A/CC reported yesterday, there is a six-month embargo on full resolution images from Friday's Stardust flyby of comet 81P/Wild 2 [link|alt]. JPL's Ron Baalke explained this to the Minor Planet Mailing list (MPML) in response to a posting from R. Mark Elowitz, who told about taking the photo that NASA/JPL released Tuesday, resampling it down to its original 1024x1024 size, and performing "iterative blind deconvolution" to obtain a much enhanced view of the comet nucleus. A copy of this result was reduced slightly to fit today's cover above.

The 300x300 animation posted by the mission yesterday has 23 of reportedly 72 flyby images. At A/CC, the nucleus was centered in each frame, and ten frames were selected where the nucleus is largest. This new animation, which is used on today's cover, was also suitably cropped and made to run slower.

Main Belt news:  It has just been brought to A/CC's attention that Franck Marchis has an extremely interesting page presently dated 16 December 2003: "Bi-lobated Shape of 121 Hermione," with the abstract of a paper on that subject, for which he is the lead author. Using a Keck Observatory 10m telescope with adaptive optics during 6-7 December 2003, observations were made of the binary Main Belt asteroid, 121 Hermione [link|alt]. The satellite was also imaged again, but the emphasis was on studying the Hermione primary, which they conclude to be "peanut" or "snowman" shaped. It could be "two connected components of radius 90 and 60 km separated by a center-to-center distance of 115 km.," or "two lobes of radius 60 and 50 km separated by 120 km and, perhaps, linked by a bridge of matter of 80 km wide." There are images, diagrams, and a movie (more promised) for demonstration.

121 Hermione will occult a 9.2 magnitude star late on February 16th UT, "mainly visible in Europe." More is available about that on Ludek Vasta's Asteroidal Occultations 2004 page (chart) and at euroaster.net (chart).

Deconvolved images for four "not bi-lobated" Main Belters are also shown from observations the same nights: 45 Eugenia, 52 Europa, 94 Aurora, and 130 Elektra.

Risk monitoring - part 1/1 Major News for 9 Jan. 2004 back top next  
Risk monitoring 9 Jan.

Today JPL re-posted 2003 YG118 with one impact solution in 2087, beyond the NEODyS 2080 time horizon. This object was previously listed by one or both monitors during December 29th to January 1st. The Friday Daily Orbit Update MPEC (DOU) has observations of this object from Great Shefford Observatory in England late last night.

Today both JPL and NEODyS removed 2004 AF, which is roughly estimated at 1.73 km. (1.08 miles) wide. Powell Observatory in Kansas reported it from early on the 7th. Table Mountain Observatory in southern California and Hobbs Observatory in Wisconsin watched it yesterday morning. Then Linz Observatory in Austria and Great Shefford caught it last night.

The DOU also reports observation of 2003 YD45 from the 2.5m Isaac Newton Telescope at La Palma in the Canary Islands that led JPL to remove this object yesterday.

Summary Risk Table - sources checked at 0142 UTC, 10 Jan

Object

Assessment

Years

VI
PS
cum
PS
max
T
S
Arc 
days
 2004 AFJPL 1/9R E M O V E D
NEODyS 1/9R E M O V E D
 2003 YS70JPL 1/92075-20751-8.36-8.3604.992
 NEODyS 12/282057-20808-7.72-8.1504.992
 2003 YG118JPL 1/92087-20871-3.32-3.32022.634
NEODyS 12/31R E M O V E D
 2003 YD45JPL 1/9R E M O V E D
NEODyS 12/30R 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.

NEODyS did some house cleaning today on its Risks page, and now has no objects under "Objects currently observable." 2003 LN6 has been put under "Lost objects," and 2003 UM3, 2003 WT153, and 2003 YS70 are now under "Objects too small to be likely to result in damage on the ground."

http://www.HohmannTransfer.com/mn/0401/09.htm
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 <webmaster@hohmanntransfer.com>.
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