By RIA Novosti,
Moscow : A Lunar Exploration Neutron Detector (LEND) has had the final touches added at the Space Research Institute of the Russian Academy of Sciences and has been sent to the US to be installed on the American Lunar Reconnaissance Orbiter (LRO), scheduled to be launched in early 2009.
The aim of the mission is to map the Moon’s surface. The task of the Russian device is to look for hydrogen and hydrogen-containing compounds, above all frozen water, in the lunar subsurface.
A companion event will be the “impacting” of the Moon to produce fresh information on our natural satellite, and also to seek water resources, presumably of cometary origin. Both the launch vehicle and the instrument container will impact the Moon.
A similar technique was used in 2005 when scientists made a study of the Tempel-1 comet, into which a copper impactor weighing 369 kg was maneuvered. Ploughing into the comet at a speed of 170 m/sec, the impactor gouged a crater the size of a football field, several dozen metres deep.
The impact released energy equivalent to the explosion of 5 tonnes of TNT and caused the comet to eject a huge cloud of matter, which was analysed by special instruments from the Deep Impact spacecraft.
Impacting is harmless for comets or the Moon. The Moon experienced the first effect of this kind in September 1959, when the Soviet Luna-2 probe crashed into it, or rather two separate machines crashed into it – the probe’s instrument package and the last stage of the launch vehicle.
A dark round spot several kilometres across that erupted four seconds after the fall spread out to 40 km while observers watched. The results of the observation proved more than interesting but were never understood by astronomers.
An abortive mission of lunar probes resulted in a hard landing on the Moon. But no special studies were made of their effects, or of the substance that was thrown up.
Having no atmosphere of its own, the Moon is constantly bombarded with the solar wind and cometary or meteoritic particles. Near its southern pole there is an impact-formed crater, which is perhaps the largest of any in the solar system.
The main aim of the NASA experiment is to validate a theory that the Moon may contain large amounts of water. Strong opinions to that effect were first voiced in 1998.
Observations from artificial satellites suggest that at least lenses of frozen water are imbedded in some craters around the poles, shadowed from the Sun.
Why is it so important to find water on the Moon?
The Moon is the immediate next stage of human expansion in the Universe and will be the first to host extra-terrestrial bases with an engineered environment.
Future colonists will need both water and its components: oxygen and hydrogen, the former for breathing and the latter as a rocket fuel, combined, of course, with oxygen.
If water supplies are found on the Moon, there will be no need to deliver them from the Earth, and the colonisation of our natural satellite will be easier.
The search for water on the Moon is also important for understanding the evolution of the solar system. The most likely scenario is one in which water would collect in beds as comets fall on the Moon. Each bed would chronicle a succession of cometary impacts over a billion or more years. This study would make it possible to trace the history of the system since its inception.
Lastly, a hotly debated theory is one in which life arrived on the Earth from space having been brought in by comets. A study of lunar cometary “leftovers” could yield fresh evidence favouring this view.
The impacting has been suggested by scientists from the Ames Research Center in California. The idea of the project, which is code-named Blue Ice, is to use the reserve capacity of the Atlas-5 launch vehicle to orbit a small additional research probe filled with optical, spectral and other equipment at the same time as the Lunar Orbiter. The probe has been named Lunar Crater Observation and Sensing Satellite, or LCROSS.
The impacting will be done by the boost section of the rocket – its Centaur upper stage weighing two tonnes. A cloud of fragments and dust will rise to a height of nine km. After an interval of 10 minutes, the probe will make a fly-through to perform the planned analysis.
A similar operation was carried out in September 2006 by specialists from the European Space Agency, who used the Smart-1 spacecraft for the same purpose. After 14 months in orbit (instead of six as scheduled), it was maneuvered towards the Moon’s Lake of Excellence and crashed onto it, sending up a column of dust, which was analysed spectrally.
A distinctive feature of the Blue Ice craft is that the Russian-made LEND probe will do preliminary reconnaissance to determine the area of the most likely occurrence of water. It is into this region that the Centaur stage will smash.