[meteorite-list] SMART-1 Swan Song: Valuable Data Until Final Moments

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon Sep 4 22:55:27 2006
Message-ID: <200609050255.TAA16537_at_zagami.jpl.nasa.gov>

http://www.esa.int/esaCP/SEMC378ZMRE_index_0.html

SMART-1 swan song: valuable data until final moments
European Space Agency
4 September 2006

Right up to its final orbits, SMART-1 continued delivering valuable data,
extending the mission's legacy as a technology and scientific success.
Scientists and engineers met today at ESOC to review mission achievements
including final AMIE camera images.

At a press event held today at ESA's Spacecraft Operations Centre (ESOC),
SMART-1 engineers, operations experts and scientists are presenting data and
preliminary results obtained by the spacecraft prior to its impact on the
Moon at 07:42 CEST [05:42 UT], 3 September 2006.

Perhaps the most sentimental image sequence was taken by AMIE just four days
before impact, on 29 August at 21:00 CEST (19:00 UT), when the camera was
pointed back towards the Earth to capture, in the best tradition of many
previous lunar missions, a view of our home planet. The sequence of images
is centred over Brazil at approximately 44.9 deg West and 19.2 deg South
(North is to the left). The Kourou area in French Guiana, from where SMART-1
was launched in 2003, is also visible.

Remarkably, this movie sequence shows the Moon passing in front of the
Earth, beautifully underlining the close gravitational relationship between
the Earth and its natural satellite.

Final orbits offered new imaging opportunities
 
During SMART-1's final orbits on 1 and 2 September, the spacecraft was
passing at extremely low altitude over the Moon's surface, which was in
darkness, prompting scientists to take advantage of this unique
observational situation by pointing the AMIE camera laterally toward the
Moon's limb (horizon). The camera gathered images of the thin dust envelope
surrounding the Moon, which will be analysed by scientists in the future.

As a result, the best final images from AMIE were taken on 2 September;
seven of these were posted on the ESA Portal on 3 September and, together
with additional images from the set, these have been combined into a pair of
movie sequences.

The images were taken between 15:19-17:34 CEST (17:19-19:34 UT). The
sequences show the surface of the Moon passing under SMART-1 during the
final orbits and show what a passenger on board the spacecraft would have
seen shortly before impact and destruction.

AMIE mosaic of geologically important southern region
 
Other SMART-1 results presented today include a mosaic of AMIE nadir
(vertical pointing) images showing a 400-km-long area inside the Moon South
Pole-Aitken Basin (SPA), the largest and oldest known impact crater basin in
the solar system and the deepest depression in the Moon.

The basin is 2600 km in diameter and extends from the South Pole to the
Aitken Crater, located at 173.4 deg East and 16.8 deg South.

AMIE was able to image the area under ideal illumination conditions, which
will afford scientists an opportunity to compare AMIE images with existing
data of the same area gathered by previous lunar missions.

"These images can help us understand the surface morphology, formation and
evolution of the South Pole-Aitken Basin. This type of nadir observation
provides the geological context of the area, and will help further extend
our knowledge of the Moon's geology," said Jean-Luc Josset, AMIE Principal
Investigator, SPACE-X (Space Exploration Institute), Neuchatel, Switzerland.

In fact, scientists intend to compare the AMIE visible images of the South
Pole-Aitken Basin morphology to those previously captured by the camera
using the 'push-broom', three-colour filter mode. The push-broom images give
information on the Moon's surface composition and mineralogy, and a
comparison between the two sets is expected to increase understanding of the
Moon's overall surface composition.

Illumination conditions at North Pole
 
Another AMIE mosaic presented today shows the Moon's North polar area and
was taken during first phase of the SMART-1 mission in 2005.

This mosaic is valuable as it shows illumination conditions at the region.
It is important to understand global illumination conditions, as this will
help in planning the location of future landing sites and, later, possible
bases on the Moon.

Successful AMIE performance

The image sets shown today illustrate the successful technology and
tremendous results of the AMIE (Advanced Moon micro-Imager Experiment)
camera throughout SMART-1's 36-month mission.

Originally designed to capture just four images per orbit, AMIE exceeded all
expectations and actually averaged 100 images per rotation, generating a
final library of some 20 000 images.

Following the early decision to redesign the science orbit and lower the
apolune (point of highest approach) from 10 000 to 3000 km over the lunar
North pole, AMIE was able to adjust to the large number of imaging commands
and complex operations that were introduced.

"This decision allowed AMIE not only to take sharp images of the South Pole
as planned, but also to study the northern hemisphere from a much shorter
range than initially foreseen," said Josset. "We now have an image library
that will keep scientists and researchers busy for the next months and
years," he added.

Additional lunar composition findings
 
Scientists used today's press event to highlight findings from spectroscopic
studies conducted by SMART-1's D-CIXS (Demonstration of a Compact Imaging
X-ray Spectrometer) instrument, and show new surface composition data of
selected regions.

The volume of data generated during the mission is expected to keep
scientists busy for some time. Among the remarkable results already
determined was the first-ever remote detection of all the main elements
which make up lunar minerals. This includes, for the first time, calcium.

"SMART-1 data have opened a new era in remote sensing investigation of
Earth's nearest neighbour. A great deal is still to be learned from analysis
of these data, while we already look forward to flying instruments similar
to D-CIXS on the upcoming Chandrayan lunar probe (India)," said Manuel
Grande, D-CIXS Principal Investigator, University of Wales, Aberystwyth, UK.

Ground observations at impact
 
Furthermore, scientists worldwide are analysing data gathered from the
ground observation campaign including the impact flash to eventually obtain
fresh information on impact physics, lunar surface science and spacecraft
behaviour during impact, all expected to be useful for future lunar
missions.

SMART-1 legacy
 
"By proving solar-propulsion and employing other technology including
innovative ground control systems while gathering fantastic new data,
SMART-1 has left a legacy of technology and scientific excellence," said
Bernard Foing, ESA's SMART-1 Mission Scientist.

He added: "It will survive by continuing to contribute to our collective
knowledge of Earth's nearest neighbour for many years, and it is only
fitting that SMART-1 has found its final resting place on the Moon."

The presentations and an audio recording from today's press event can be
downloaded as PDF files from the links below.

For more information:

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

Jean-Luc Josset, AMIE Principal Investigator
Space-X (Space Exploration Institute), Neuchatel, Switzerland
Email: jean-luc.josset _at_ space-x.ch

Manuel Grande, D-CIXS Principal Investigator
University of Wales, Aberystwyth, United Kingdom
Email: mng _at_ aber.ac.uk

[NOTE: Images supporting this release are available at
http://www.esa.int/esaCP/SEMC378ZMRE_index_1.html ]
 
Received on Mon 04 Sep 2006 10:55:23 PM PDT