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NASA offensive on Mars
By Matthias Gründer
Our closest neighbour in space, the Red Planet, has exercised a special fascination on scientists since time immemorial. With the long-term goal of a manned mission in mind, NASA is sending a series of exploratory space probes to Mars.
One reason for the interest in Mars is the simple fact that, being our closest neighbour in the solar system, it can be reached in a relatively short time. If one ignores the minor problems of the weaker gravitational force, the lower midday temperatures and the lack of any vegetation, it would appear that humans could live and work there. However, at least the first missions and the first phase of any possible permanent residence of astronauts on the planet surface will almost certainly be dependent on Earth-based supplies of water, food, breathable air, fuel etc., the same things which at present have to be supplied from Earth to the resident crews onboard the International Space Station, who are living in airless space.
Meanwhile the mission planners are already divided over the question of water, for although no water has yet been found on Mars, all the signs and orbital investigations conducted to date suggest that the Red Planet must once have harboured raging torrents and large expanses of water. But where have these huge volumes of water gone, and could anything possibly remain of them, perhaps deep below the surface?
Again, scientists are not certain about the fuel situation, since to this day we know hardly anything about what natural deposits of minerals there might be. It seems unlikely that there could be any oil or natural gas due to the lack of prehistoric plant cover, but even this possibility has not yet been entirely ruled out. And further exploration has still to be carried out to discover what else might be lurking beneath the surface. Is there any possibility that energy sources for future spacecraft propulsion could be found directly on Mars?
These are just two of many questions which still have to be answered, and since President Bush announced the US “Moon, Mars and Beyond” space programme, it seems that manned flights to Mars are planned for 20 years' time. At any rate, this is what it says in the relevant documents, even if to this day no one knows where the huge financial resources to fund such a programme will come from. It is clear that any future Mars missions will require enormous technical and scientific preparations, and it is for this reason that NASA unveiled its Mars research programme to the taxpayers back on 26 October 2000.
This decade alone is to see six wide-ranging scientific undertakings, and in the preliminary stages great emphasis has been placed on the importance of not repeating the mistakes of the past. These include the loss of the approx. $1 billion Mars Observer, which was launched on 25 September 1992 but suddenly gave up the ghost after landing on the Red Planet. Subsequent investigation brought to light a coordination problem between the different institutions involved in the construction of the equipment: whereas one side were still using the mediaeval system of imperial measurements, the other was using the metric system, and the combination was too much for the on board computer.
Both the Mars Climate Orbiter (launched on 11 December 1998) and the Mars Polar Lander (3 January 1999) succeeded in reaching Mars, but due to technical problems failed to carry out their mission tasks. NASA is determined that it will never again have to explain such embarrassing setbacks, even if the USA is in good company in this area. For example, the Russians have over the years launched 20 different spacecraft bound for the Red Planet, yet only three of them performed their mission tasks satisfactorily and 13 of them never reached their mission destination. Even the single Japanese Mars space probe, Nozomi, never reached the big red disc and will now orbit the Sun for evermore.
The Mars Exploration Programme set out the following ambitious missions for the first decade of the twenty-first century:
Mars Odyssey (launched 7 April 2001): an orbiter intended to take exploratory photographs and to research the geography, climate and mineralogy. One important objective was also to explore possible landing sites for the Phoenix Scout mission.
Mars Exploration Rovers (MER), (10 June and 8 July 2003): two Mars vehicles, better known as Spirit and Opportunity, which were primarily planned as mobile field geologists and atmospheric researchers and, to the joy of all the participating scientists, are still bravely fighting their way through the boulders.
Mars Reconnaissance Orbiter (MRO) (10 August 2005): this was equipped with the most accurate planetary camera so far, which was sent to a different celestial body, and with a special device intended to detect any possible underground water reservoirs.
Phoenix (August 2007): a small, low-cost lander built as part of NASA's Scout programme, which was actually supposed to fly to Mars back in 2001 with the Surveyor space probe, but this was then cancelled. Phoenix will now carry out the slightly modified research programme of the already mentioned, unsuccessful Mars Polar Lander at the north pole.
Mars Science Laboratory (end of 2009): also a rover, but twice as big and three times as powerful as the present MERs. It is intended to perform geological exploration involving several international partners. For this purpose, it is to carry amongst other things a Russian hydrogen detector, a Spanish meteorology package and a Canadian spectrometer.
The research programme for the second decade of this long-term plan once again envisages a mixture of orbiter, lander and rover missions, with the first ground samples of the Mars surface to be sent back to Earth in 2014 and 2016. However, there is still no concrete information about this, and it is possible that technological advances could bring forward a few of the planned flights. There is also already talk about miniaturised surface experiments or deep boring down to a depth of several hundred metres, although the technologies required for such endeavours do not yet exist.
At any rate there are plans to launch various automated planetary research vehicles at regular intervals every 26 months, to coincide with the times when the journey between Earth and Mars is at its shortest so that the smallest amount of fuel has to be carried. If one mission were to fail, this would mean waiting more than four years, a delay which is too long for the insatiable thirst for knowledge of the specialists on the ground, who already have their sights set on the long-term goal of the first manned flight.
For, despite all the technical advances and the fascination for automated capabilities, the laboratories and Mars vehicles equipped to the teeth are lacking in one important property: they are only machines which lack curiosity and the innate compulsion to research and to discover of humans. Even the best film and television pictures of Mars's surface are not enough to satisfy the humans here on Earth. They yearn to stand on the planet, to sense, see, smell and taste for themselves its low gravitational force and dust storms. That is why the astronauts on board the International Space Station are already conducting research into medical, biological and psychological problems with a view to future long-duration flights in space. At the end of the day the objective is that humans and machines should together conquer Mars.
From FLUG REVUE 1/2007
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