[meteorite-list] SMART-1 Impact Flash and Debris: Crash Scene Investigation

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Sep 7 12:08:27 2006
Message-ID: <200609071449.HAA26502_at_zagami.jpl.nasa.gov>

http://smart.esa.int/science-e/www/object/index.cfm?fobjectid=39969

SMART-1 impact flash and debris: crash scene investigation
European Space Agency
7 September 2006

The SMART-1 observation campaign latest results bring new evidences on
SMART-1 impact: timing, location, detection of flash and ejecta, and
a firework.

"The successful capture of the SMART-1 impact from Earth raised a
substantial interest in the amateur and professional astronomical community.
They started to reanalyse the available data, to repeat observations of the
impact site and to share the results worldwide as a family", says Pascale
Ehrenfreund, coordinator of the SMART-1 impact ground observation campaign.

Where did SMART-1 impact the Moon?
 
"From the various observations and models, we try to reconstruct the 'movie'
of what happened to the spacecraft and to the Moon surface," says ESA
SMART-1 Project scientist Bernard Foing. "For this lunar 'Crash Scene
Investigation', we need all possible Earth witnesses and observational
facts."

The actual SMART-1 impact took place on 3 September 2006 in the course of
the spacecrafts 2890th orbit around the Moon. SMART-1 sent its last signals
to Earth at 07:42:21:759 CEST (05:42:21:759 UT), and the JIVE radio
telescope from Hobart, Tasmania, measured a loss of signal a few moments
later, at 07:42:22.394 CEST (05:42:22.394 UT).

These times are remarkably in agreement with the last SMART-1 flight
dynamics predictions of 3 September at 07:42:20 CEST (05:42:20 UT), in the
location at 46.20 deg West longitude and 34.4 deg South latitude.

This is also in agreement with the coordinates newly derived from the
position of the infrared impact flash observed by the Canada-France-Hawaii
telescope (CFHT).

Extensive data processing is now going on to specify the topography of the
impact site.

>From a preliminary analysis of the topographic stereo data available and
earlier maps built with SMART-1 data, the satellite should have hit the Moon
in the ascending slope of a mountain about 1.5 kilometres high, above the
Lake of Excellence plain.

What happened? Dust after the flash
 
To determine what part of the flash comes from the lunar rock heated at
impact or from the volatile substances released by the probe, it is
important to obtain measurements in several optical and infrared
wavelengths, in addition to the CFHT observations (2.12 microns).

>From a detailed analysis of the CFHT infrared movie of the variations after
the flash, a cloud of ejected material or debris travelling some 80
kilometres in about 130 seconds has been detected by observer Christian
Veillet, Principal Investigator for the SMART-1 impact observations at CFHT.

"It seems that some ejecta or debris made it across the mountain. This is
good news to search for the ejecta blanket" says Foing." We might also see
the 'firework' expansion of gas and debris that has bounced after impact
from the spacecraft."

Some SMART-1 campaign amateurs report that they may have observed the
optical flash in their own data, and a possible impact afterglow. "We call
for observers to search for the crater and ejecta blankets from SMART-1, in
particular using visible or infrared imagery, or even to look at
spectroscopic anomalies at the impact site," added Foing. "We also call all
observers to send us their reports, thanking them for engaging in the
SMART-1 adventure".

Note to editors
 
The five radio telescopes involved in the SMART-1 observations and
coordinated by the Joint Institute for VLBI (Very Long Baseline
Interferometry) in Europe (JIVE), are: the Medicina (INAF) 32- metre antenna
in Italy, the Fortaleza (ROEN) 14-metre antenna in Brazil, the
German-Chilean TIGO (BKG) 6-metre antenna in Chile, the Mount Pleasant
Observatory of the University of Tasmania (Australia) and the Australia
Telescope Compact Array (CSIRO).

The SMART-1 impact observation campaign involved a core of participating
telescopes, including: the South African Large Telescope (SALT), the Calar
Alto observatory in Andalucia, Spain, the ESA Optical Ground Station (OGS)
at Tenerife, Spain, the TNG telescope in La Palma, Canary Islands, Spain,
the CEA Cariri observatory in Brazil, the Argentina National Telescope, the
Florida Tech Robotic telescopes at Melbourne FL and Kitt Peak, MSFC lunar
meteor robotic telescopes, Houston 1m, Big Bear Solar Observatory, MDM
telescopes at Kitt Peak, NASA IRTF, the Canada-France-Hawaii Telescope, the
Japanese Subaru Auxiliary telescopes on Hawaii, the ODIN space observatory.
We acknowledge also support from Nottingham University, and the USGS.

Reports on data gathered by other observatories that joined the campaign
will follow on this site.

For more information:
 
Bernard H. Foing, ESA SMART-1 Project Scientist
Email: bernard.foing _at_ esa.int

Pascale Ehrenfreund, SMART-1 ground-based impact campaign coordinator,
Leiden University, The Netherlands
Email: pascale _at_ strw.leidenuniv.nl

[NOTE: Images supporting this release are available at
http://www.esa.int/esaCP/SEMWX03VRRE_index_1.html ]
Received on Thu 07 Sep 2006 10:49:48 AM PDT