05 May 2000
The Lunar Exploration Open Session was convened by Bernard Foing, and sponsored by the International Lunar Exploration Working Group (ILEWG), the European Space Agency and space agencies from France, Italy, Britain and Germany. It brought together some of the world's leading lunar scientists, engineers and project managers and was also the occasion to present the latest findings from past missions.
Forty papers were presented orally, and there was a very lively poster session. Science papers by Dunkin, Heather, Hiesinger, Koehler, Chevrel and collaborators covered last results from the analysis of integrated datasets from the Clementine and Lunar Prospector missions, in such fields of research as the nature and creation of the Moon's basaltic maria, and highlands, with emergence of "New views of the Moon". In this context, Apollo sample analysis provides local ground truth and seismic investigations allow a more precise measurement of the thickness of the lunar crust. The eventual presence of ice or water-ice in the permanently shadowed craters of the lunar South and North poles was evoked, notably by Stuart Nozette, Project Manager for the Clementine orbiter mission (1994) which provided initial radar data suggesting this possibility.
Vladimir Zharkov of Moscow Institute of Earth Physics presented his theory on how the study of the lunar orbit provides important information about the history of the Moon and the formation of our planet's continents. Evidence for and against a possible "dynamo effect" of the Moon's core in its past (which could shed light on lunar volcanism and the origin of the magnetism of certain lunar rocks) was also discussed by Pierre Rochette of the University of Aix-Marseille.
Several soil spectroscopy calibration facilities have been developed in Europe and in the world for the interpretation of remote sensing measurements (from X-ray, ultraviolet, visible, infarred and radio). Patrick Pinet presented the Toulouse's Wide Field Spectral Imaging Facility. This optical testbench, detector and light-source system will use soil and mineral samples to evaluate data obtained with the increasingly precise science cameras now equipping space missions. Fifteen papers were presented in relation to the preparation of the instruments and the science of SMART-1. The SMART-1 project manager Giuseppe Racca, gave a status report on the spacecraft development. The SMART-1 payload principal investigators presented to the community, the goals and status of development of the AMIE, SIR, D-CIXS, SPEDE/EPDP instruments. Upcoming lunar missions were described in great detail. SMART-1 will probably be the first to leave for the Moon, as from the end of 2002. Japan should follow in early 2003 with Lunar-A and its ambitious scheme to fire penetrators, incorporating sensors, into the Moon surface. Project Manager Hitoshi Mizutani (ISAS) explained that "the objective is to measure 'moonquakes', providing additional seismic constraints on the lunar core and deep internal structure". As the Lunar-A orbiter will not be able to see the actual penetrator impacts, SMART-1 project scientist Bernard Foing suggested that the AMIE camera on ESA's spacecraft could try to observe and locate them. The following Japanese mission of ISAS/NASDA, Selene, is now scheduled for a 2004 launch according to its Project Scientist Susumu Sasaki (ISAS). The mission includes an orbiter and two sub-satellites carrying in all 10 different experiments, including a high-power radar that will be able to sound the lunar crust to a depth of 5km. More than 200 scientists are working on Selene and Bernard Foing congratulated his Japanese colleagues: "The SMART-1 spacecraft may have a "CAN" bus as used on the Mercedes-S, but Selene is surely the Rolls Royce of lunar exploration".
The open session confirmed the general consensus that our knowledge of the Moon will inevitably require in-situ robotic exploration. If only to confirm the existence of ice as Stuart Nozette explained. "Before working in the space field, I used to drill oil wells. On the basis of the Clementine shadow and radar data, and Lunar Prospector neutron data, I would say: 'Right, let's go-ahead and drill some test wells'. SMART-1's instruments will certainly help map the shadows, but we still need something active to actually look in and see whether the patch on the wall of the Shackleton crater actually is ice. Ultimately, nobody is going to believe you until you actually dig some out!"
New concepts for the wheels of lunar micro-rovers and a remotely operated chemical and mineralogical analyser were presented during the lunar session. Jean Heidmann (Observatoire de Paris) restated his proposal to establish a radio-frequency observatory in a crater on the farside of the Moon, given the increasing interfence from ground and Earth satellite systems. Participants also learnt of the latest proposals on how oxygen, vital for eventual human exploration, can be extracted from lunar materials, notably from lunar glass.
At the end of the day, one could not but share the conviction that lunar scientific and technical exploration is fully justified and must be pursued. Earth's natural satellite is so close to us but in itself still holds so many mysteries . "Furthermore, says ILEWG chairman Bernard Foing, "the Moon and lunar missions are increasingly usefull as testbeds for other planetary destinations (such as Mars and Mercury). The EGS 2000 lunar session, with its wide variety of reaffirmed the importance of European and international cooperation. The next steps for action and coordination will be discussed during the 4th International Conference on Exploration and Utilisation of the Moon (ICEUM4) to be held at ESTEC, Noordwijk, NL on 10-15 July 2000".
Lunar-A project manager Hitoshi Mizutani and SMART-1's Bernard Foing envisage more joint operations for their missions.
ROYAL ASTRONOMICAL SOCIETY
11 November 1999
Smart-1 will be the first ESA spacecraft to orbit the Moon. On board the revolutionary spacecraft will be an innovative science instrument which has largely been designed and built in the U.K. This small, lightweight instrument, known as the Demonstration of a Compact Imaging X-ray Spectrometer (D-CIXS), will reveal the composition of the Moon for the first time.
"Despite decades of research, we have never fully discovered what the Moon is made of," said Dr. Manuel Grande of Rutherford Appleton Laboratory, who is the Principal Investigator for the D-CIXS instrument.
"The Apollo missions only explored the equatorial regions on the Earth-facing side of the Moon, while other spacecraft only investigated surface colour or searched for water and heavy elements," he explained.
D-CIXS will measure the Moon's surface composition by detecting X-rays coming from the lunar surface. It is designed to seek out the different minerals which make up lunar rocks by detecting X-rays emitted from the surface.
"As X-rays from the Sun strike the Moon, they excite the rocky elements such as silicon, calcium, magnesium and aluminium and iron," explained Dr. Grande. "Secondary X-rays produced by these minerals give unique signatures for each element. By studying these emissions, we can tell what the rocks are made of."
"If the Moon is really made of green cheese, we'll be the first to tell the world," he added.
The U.K. team hopes that D-CIXS will be the first of a new generation of X-ray imagers for future planetary observation, including a possible mission to the innermost planet, Mercury.
Funding for the D-CIXS project has been provided by several partner agencies of the British National Space Centre.
SMART-1 is the first of the Small Missions for Advanced Research in Technology of ESA's Horizons 2000 Science programme. Scheduled for launch to the Moon in 2002, the mission's main objective is to demonstrate innovative and key technologies for scientific deep-space missions.
One of these key technologies is a solar electric (ion) engine, which will provide the spacecraft's primary propulsion. This will be the first use of such an ion engine for primary propulsion in Europe and is considered an essential step towards cheaper missions with large velocity requirements, such as a Mercury orbiter.
For further information and pictures visit the ESA Science Web sites at: http://sci.esa.int/smart