- Email: [email protected]
The Moon and Mars
The Moon and Mars Role and impacts for Europe
Francis Theillier and Patrick Eymar
Interest in manned interplanetary exploration and colonization has been reviving for some time. Despite being presently involved in the three main programmee Arlane 5, Hermes and Columbus, Europe should not stay out of Moon/Mars-related initiatives. This paper summarizes the major results of a study on the role Europe could play in such a context and the impacts this could have on its space policy. Francis TheUlier and Patrick Eymar are with the Technical Directorate, Space and Strategic Systems Division of Aerospatiale, BP 2, 78133 Les Mureaux Cedex, France. This paper presents a summary of Aerospatiale analyses; the ideas expressed here should not be considered as an official European position.
At the very time when attention is focused on manned space stations in low Earth orbit (LEO), space conquest and interplanetary exploration, or more generally future long-term space initiatives, seem to have returned to the foreground of the scene. This revival of interest has mainly been evident in the USA and the USSR, the first signs being followed by official statements clearly considering manned missions towards Mars within the next four decades. In this respect, preliminary unmanned exploration programmes are currently in progress in most of the leading space countries. Europe is presently deeply involved in three main programmes (Ariane 5, Hermes and Columbus) which should reach operational status around the beginning of the next century, and has up to now not been precisely committed to any interplanetary manned mission, but this should not keep it out of an international space exploration programme. Aerospatiale has therefore already performed various studies aimed at analysing Moon/Mars mission scenarios, together with the associated functional architecture that would be required, different schedules and degrees of involvement that could be envisaged, as well as the impacts such activities may have on current programmes.
Moon/Mars missions: why? Many reasons have been set out to account for the return to the Moon or for the settlement of the red planet. Unlike the competitive climate that was prevalent at the time of the lunar conquest, the current tendency would be to put forward the benefits for mankind and the positive technical and technological spin-offs that could and would result from a new breakthrough in manned space exploration. These arguments arc well known 1 and will therefore not be detailed here. They may be globally divided into four main families: 1The Case for an International Lunar Base, IAA Ad-hoc committee 'Return to the Moon', 1988; W.W. Mendell, ed, Lunar Bases and Space-Activities of the 21st Century, Lunar and Planetary Institute, Houston, TX, 1985.
316
• • • •
scientific objectives; 'utilitarian' objectives; political objectives; and 'humanistic' objectives. 0265-9646/91/040316-07 © 1991 Butterworth-Heinemann Ltd
The Moon and Mars: role and impacts for Europe
Figure 1. Examples of surface building and possible base-building sequence. These obviously do not all have the same degree of credibility and do not take into account fundamental aspects such as cost. Actually, only a few objectives seem worth considering, mainly scientific activities leading to a better knowledge of the Solar System and activities linked to outpost and space transportation nodes aspects. Moreover, it seems that the Moon and Mars should be considered in two slightly different ways: the Moon is a rather particular case since it is close to the Earth and already visited, while Mars is much more constraining in terms of journey and remains unexplored, but would attract more media attention.
Moon/Mars missions: h o w ? Four main points affect such missions: • • • •
technical aspects; human aspects; financial aspects; and political aspects.
Five main technical aspects may be distinguished: transportation, in-orbit infrastructure, surface elements, communication networks, ground segment (Earth). The transportation segment is itself basically made of four elements: launchers (classical or advanced, expendable or reusable, including aerospace planes currently under study within most space countries) for Earth-to-orbit transportation; orbital transfer vehicles and landers (both likely to be different for equipment and crews); and surface vehicles for planet exploration and base building. The in-orbit infrastructure constitutes the second fundamental element of such missions since it would consist of a network of transportation and support nodes (including pre- and post-mission support roles such as crew training and quarantine) in both Earth and lunar or martian orbits. In this respect, it also includes rescue vehicles. The surface elements mainly consist of pressurized modules for housing, laboratories and other facilities, as well as of missiondependent tools (Figure 1). The communication networks, of paramount importance for any kind of mission, include at the same time Earth-based antennae, LEO, lunar
SPACE POLICY November 1991
317
The Moon and Mars: role and impactsfor Europe
or Mars satellites, and the various in-orbit stations and surface bases. Local networks will also have to be developed within surface bases. The ground segment consists, as usual, of tracking stations and mission preparation/integration/launch facilities. Human aspects are of tremendous importance and constitute one of the most critical areas which need to be carefully investigated. Financial aspects may be much more problematic and are likely to impact strongly on the selection of the mission scenarios. Indeed, the situation seems to have evolved year after year from significant support of space programmes by public funds at the beginning of space conquest to limited national support, illustrated by more numerous and drastic cuts in space budgets, more space programmes being today actually dedicated to 'commercial' or military activities. In this context, and especially considering the various cost estimations that have been performed for a few years concerning Moon/Mars missions, the question of funding may appear as a major obstacle to a new era of humans in space, although it might perhaps be at least partly removed if lasting international cooperation could be achieved. Political aspects are closely linked to the previous elements: indeed, since private funds would obviously not be sufficient and would anyway probably not be unconditionally offered if no tangible profit is expected, public funds will be required, and realistic financing without global political will and public support would probably not last very long. In addition, and once the political will is established, the question of international cooperation will also have to be considered, since it may again face political obstacles such as leadership aspects, problems linked to technological transfer or task sharing, duration of cooperation, etc.
Three scenarios for Europe's role Several other parameters will influence the selection of Moon/Mars mission scenarios, such as the dates and deadlines considered for these missions, their duration, their degree of automation and their autonomy. A simple return to the Moon would not appear to be particularly newsworthy, since it was achieved 20 years ago. If planned, it should therefore first be manned and then be presented in the framework of more ambitious missions towards Mars, for which the Moon could be used as an outpost or to conduct experiments, perform crew training or extract propellant. On the other hand, a direct mission to Mars does not seem very realistic today without preliminary experience that could be ideally gained from the Moon. A few scenarios (although there are many others) are considered here for the purpose of analysis of the part Europe may play if a manned interplanetary programme is decided (see Table 1). Scenario 1: general consensus and full international cooperation
This would be an ideal case, especially if adequate funding is assumed, in which case the dates that have been put forward for humans on Mars (2020-30) could well be achieved. Three subscenarios may again be distinguished: Scenario l(a): Mars exploration (reference scenario). The first step in
318
SPACE POLICY November 1991
The Moon and Mars: role and impacts for Europe Table 1. Summary of Europe's role in several scenarios. Scenario 1(a)
Objective Mars exploration
Cooperation Full
1(b)
Mars exploitation/colonization
Full
1(c) 2(a),2(b),2(c)
Moon colonization As for 1(a),l (b),l (c) respectively
Full Limited
3(a),3(b),3(c)
As for 1(a),1(b), 1(c) respectively
None
2p. Zgirski and M. Grimard, 'Space station building and assembly optimization', IAF9 0 - 0 9 3 , A e r o s p a t i a l e , Les M u r e a u x , France.
SPACE POLICY November 1991
European participation Participation in automatic exploration, support node and Hab/Lab modules, Participation in communication networks, launchers and orbital vehicles, and landers. Possible participation in any technological field. As for Scenario 1 (with probably different levels of participation as a function of the domain). All (possible commercial agreements with others).
this scenario would be automatic/robotic exploration of the Moon and Mars. The second step would be a test base on the Moon, supported by Earth (logistics). The third step would be the establishment of a first temporary base on Mars, with minimal infrastructure. The fourth step would be the establishment of a network of bases on Mars and an in-orbit infrastructure. The role Europe could play in such a scenario could be as follows. First, Europe has already taken part in the automatic exploration of Mars through participation in the 'Phobos', 'Mars Observer' and 'Mars '92' missions, and has also already defined three main European axes of involvement in planetary exploration: orbital science for mapping and imaging; network science using penetrators, semi-hard landers or balloons; and rover science for mobile surface exploration. Since Europe's expertise and technological competence have already been demonstrated through many satellite and probe programmes, its commitment to the field of automatic exploration may well be extended and increased. Looking at the main segments identified above, several factors may be noted. Countries such as the USA or the USSR already have much more substantial experience in space stations, long-duration flights and extra-vehicular activity (EVA) than Europe, and therefore the role Europe could play in such fields would obviously not be a leading one. However, European countries have for roughly 10 years been performing various studies in the domain of in-orbit infrastructure e and may well be in charge of, for instance, pressurized modules, for either in-orbit stations or surface bases. In the same way, a European Manned Space Infrastructure (EMSI), today scheduled to be achieved within the first two decades of the 21st century, could be used as a support node. As regards the Earth-to-orbit transportation, and in spite of the fact that the USSR, the USA and Japan also have launchers, Ariane 5 and Hermes, together with their derivatives, could play an important part for flexibility and cost reasons. This family may also be completed by transfer vehicles capable of rendezvous and currently under study for ESA, such as ATV or LOVE, as well as by escape vehicles for space stations. All the other segments are in early stages of development as regards the Moon and Mars and thus seem to remain open to European participation. Europe may thus again be present in the field of landing vehicles with derivatives of the above-mentioned spacecraft, or thanks to the competence it has acquired in several kinds of propulsion, including nuclear or ionic propulsion. Technological expertise and experience gained in communications and associated networks would also enable Europe to take part in this field. 319
The Moon and Mars: role and impactsfor Europe Nevertheless the part played by each participant will strongly depend on its degree of financial involvement in the programme and on its position in the programme organization. Scenario l(b): exploitation of Mars (optimistic scenario). Steps 1 to 3 would be the same as Scenario l(a). The fourth step would be autonomous, permanently manned industrial settlement. This scenario does not seem very credible today, since the cost of an industry on Mars would be prohibitive for the opportunities currently foreseen. There would not be major changes compared with the previous scenario as regards the role of Europe, except that the vehicles and infrastructure required would be slightly different, but without major technological differences. Scenario 1 (c) : colonization of the Moon (pessimistic scenario). The first step would be automatic/robotic exploration of the Moon. The second step would be a temporary base on the Moon, supported by Earth (logistics). The third step would be a permanently manned base, supported by Earth. The fourth step would be an autonomous permanently manned base. The conclusions as regards the role Europe may play in this scenario again remain the same as previously, except that a limited scenario would result in reduced infrastructure and reduced roles for each participant, and such missions would require fewer new developments since they could roughly be achieved with existing technologies. It may be recalled here for instance that an Ariane 5 launcher can send 22 tonnes into LEO and roughly 5 tonnes into lunar orbit (up to 9 tonnes with an already foreseen improved version), and could thus be used for instance for logistic support while heavy launchers (eg Energiya) could be used to send pressurized modules or landers. Europe could also have a significant role in surface bases if in-orbit infrastructures and heavy launchers were provided by nations which have already developed them. However, it must be noted that all the participating countries would be required to play a part in this segment, which would be the only real novelty, and again the percentage of financial participation would be a major factor. Scenario 2: limited cooperation (eg Western countries only) This scenario would lead to more critical problems of funding and development, but the previous subscenarios could be kept, though delays would be likely to occur. It does not seem that particular technological problems would arise from this limitation of cooperation. However, some experience would have to be gained, for instance as regards long-duration flights, and, considering the background of the Western countries, this task would probably be covered by the USA. Moreover, the lack of a heavy-lift launcher would probably be a handicap which would require either the development of a new expendable launcher (the US ALS or European) or the improvement of a cargo shuttle, probably under US responsibility. This does not greatly change the position of Europe itself, nor the conclusions of Scenario I as regards the European potential, but it could increase its relative part in other areas (eg transfer vehicles, surface elements, landers, rovers and communication networks).
320
SPACE POLICY November 1991
The Moon and Mars: role and impacts for Europe Scenario 3: no cooperation
This pessimistic case could very well mean the withdrawal of manned missions to Mars or their postponement to a much later date, at least for E u r o p e alone. The role of Europe in such a scenario would be obvious since it would have to achieve everything on its own. In this case, European in-orbit infrastructures, for instance, would not remain confined to support roles but would be indispensable, which would in turn require experience. The same remarks could be made for almost any of the previously identified segments. However, if Europe decided from now on to aim at this kind of situation, which is very unlikely, or was certain that it would occur, several options could be decided from the beginning. For instance, it could be decided not to design and develop a new heavy-lift launcher but rather to develop in-orbit assembly/building techniques, together with improvements to the performance of current launch means and an increase in launching flexibility (number of launch pads, ground facilities, etc). Moreover, even if no real cooperation were envisaged, commercial agreements could perhaps be considered (although this is doubtful), at least initially: it may be envisaged, for instance, to buy propellant from a non-European production unit on the Moon if any exist, or to buy a US or Soviet launcher, or to rent surface modules within already existing bases.
Impacts on current or future European programmes These impacts are of two kinds. Impacts of such missions on future programmes that will be decided after a Moon/Mars scenario is selected will of course be implemented from the beginning, while impacts on current programmes or on programmes that will be in progress at the time the decision to undertake a Moon/Mars mission will be made will depend on the degree of completion of these programmes and on the possibility of reorienting them. The major E u r o p e a n programmes that would be likely to be affected by these missions today would be mainly Ariane 5, Hermes and Columbus, as well as, to a smaller extent, the foreseen European transfer vehicle and the future space infrastructure or a possible aerospace plane. Ariane 5, for instance, would belong to the first category. Improvements are already foreseen to increase its performance or decrease its cost with more powerful engines and solid boosters, liquid boosters, improved cryogenic stage, reusable boosters or twin engines. However, it is not likely that its performance will be increased up to more than say roughly 35 tonnes in L E O without designing something radically new. The same applies to Hermes though its degree of development is lower than that of Ariane 5, to which it is, however, closely linked: derived versions used as space taxis for crews of up to 10 or as escape vehicles may be envisaged. For Columbus, several standard modules may need to be assembled if needed to form a station that would be larger than the Columbus Free Flyer and more autonomous than the Attached Pressurized Module. However, many aspects would first have to be developed, such as a large altitude control system and power generation. In this it may perhaps be considered as an intermediate case, since the ultimate
SPACE POLICY November 1991
321
The Moon and Mars: role and impacts for Europe
European space station is not scheduled to be completed before 2010 and its status would rather make it part of the last scenario. Some analyses of the impacts Moon/Mars missions would have on space stations have already been made at Aerospatiale: a station foreseen first as a laboratory to develop new technologies and to observe the Earth would have to evolve towards a transportation and support node, providing vehicle assembly, check-out and refurbishment facilities, propellant storage and housing for crews. Similar remarks could be made as regards the currently foreseen transfer vehicles, since their design status is today such that they could still be optimized in the aim of Moon/Mars scenarios; however, if these vehicles were to be launched by Ariane 5, they would already be constrained.
Conclusion Manned missions towards Moon or Mars seem to have been coming back to the foreground of the international scene for some time, and in spite of its current commitment in several major programmes, Europe should also play a part in this field, especially as it already has the right means and competence to do so. Its role would of course be a function of its degree of involvement and of the cooperation strategy adopted, as well as of the new developments that would be required. If such a programme took place, it would obviously affect existing or upcoming European elements by requiring improvements or reorientations, and would therefore greatly influence Europe's future in space.
322
SPACE POLICY November 1991
Francis Theillier and Patrick Eymar
Interest in manned interplanetary exploration and colonization has been reviving for some time. Despite being presently involved in the three main programmee Arlane 5, Hermes and Columbus, Europe should not stay out of Moon/Mars-related initiatives. This paper summarizes the major results of a study on the role Europe could play in such a context and the impacts this could have on its space policy. Francis TheUlier and Patrick Eymar are with the Technical Directorate, Space and Strategic Systems Division of Aerospatiale, BP 2, 78133 Les Mureaux Cedex, France. This paper presents a summary of Aerospatiale analyses; the ideas expressed here should not be considered as an official European position.
At the very time when attention is focused on manned space stations in low Earth orbit (LEO), space conquest and interplanetary exploration, or more generally future long-term space initiatives, seem to have returned to the foreground of the scene. This revival of interest has mainly been evident in the USA and the USSR, the first signs being followed by official statements clearly considering manned missions towards Mars within the next four decades. In this respect, preliminary unmanned exploration programmes are currently in progress in most of the leading space countries. Europe is presently deeply involved in three main programmes (Ariane 5, Hermes and Columbus) which should reach operational status around the beginning of the next century, and has up to now not been precisely committed to any interplanetary manned mission, but this should not keep it out of an international space exploration programme. Aerospatiale has therefore already performed various studies aimed at analysing Moon/Mars mission scenarios, together with the associated functional architecture that would be required, different schedules and degrees of involvement that could be envisaged, as well as the impacts such activities may have on current programmes.
Moon/Mars missions: why? Many reasons have been set out to account for the return to the Moon or for the settlement of the red planet. Unlike the competitive climate that was prevalent at the time of the lunar conquest, the current tendency would be to put forward the benefits for mankind and the positive technical and technological spin-offs that could and would result from a new breakthrough in manned space exploration. These arguments arc well known 1 and will therefore not be detailed here. They may be globally divided into four main families: 1The Case for an International Lunar Base, IAA Ad-hoc committee 'Return to the Moon', 1988; W.W. Mendell, ed, Lunar Bases and Space-Activities of the 21st Century, Lunar and Planetary Institute, Houston, TX, 1985.
316
• • • •
scientific objectives; 'utilitarian' objectives; political objectives; and 'humanistic' objectives. 0265-9646/91/040316-07 © 1991 Butterworth-Heinemann Ltd
The Moon and Mars: role and impacts for Europe
Figure 1. Examples of surface building and possible base-building sequence. These obviously do not all have the same degree of credibility and do not take into account fundamental aspects such as cost. Actually, only a few objectives seem worth considering, mainly scientific activities leading to a better knowledge of the Solar System and activities linked to outpost and space transportation nodes aspects. Moreover, it seems that the Moon and Mars should be considered in two slightly different ways: the Moon is a rather particular case since it is close to the Earth and already visited, while Mars is much more constraining in terms of journey and remains unexplored, but would attract more media attention.
Moon/Mars missions: h o w ? Four main points affect such missions: • • • •
technical aspects; human aspects; financial aspects; and political aspects.
Five main technical aspects may be distinguished: transportation, in-orbit infrastructure, surface elements, communication networks, ground segment (Earth). The transportation segment is itself basically made of four elements: launchers (classical or advanced, expendable or reusable, including aerospace planes currently under study within most space countries) for Earth-to-orbit transportation; orbital transfer vehicles and landers (both likely to be different for equipment and crews); and surface vehicles for planet exploration and base building. The in-orbit infrastructure constitutes the second fundamental element of such missions since it would consist of a network of transportation and support nodes (including pre- and post-mission support roles such as crew training and quarantine) in both Earth and lunar or martian orbits. In this respect, it also includes rescue vehicles. The surface elements mainly consist of pressurized modules for housing, laboratories and other facilities, as well as of missiondependent tools (Figure 1). The communication networks, of paramount importance for any kind of mission, include at the same time Earth-based antennae, LEO, lunar
SPACE POLICY November 1991
317
The Moon and Mars: role and impactsfor Europe
or Mars satellites, and the various in-orbit stations and surface bases. Local networks will also have to be developed within surface bases. The ground segment consists, as usual, of tracking stations and mission preparation/integration/launch facilities. Human aspects are of tremendous importance and constitute one of the most critical areas which need to be carefully investigated. Financial aspects may be much more problematic and are likely to impact strongly on the selection of the mission scenarios. Indeed, the situation seems to have evolved year after year from significant support of space programmes by public funds at the beginning of space conquest to limited national support, illustrated by more numerous and drastic cuts in space budgets, more space programmes being today actually dedicated to 'commercial' or military activities. In this context, and especially considering the various cost estimations that have been performed for a few years concerning Moon/Mars missions, the question of funding may appear as a major obstacle to a new era of humans in space, although it might perhaps be at least partly removed if lasting international cooperation could be achieved. Political aspects are closely linked to the previous elements: indeed, since private funds would obviously not be sufficient and would anyway probably not be unconditionally offered if no tangible profit is expected, public funds will be required, and realistic financing without global political will and public support would probably not last very long. In addition, and once the political will is established, the question of international cooperation will also have to be considered, since it may again face political obstacles such as leadership aspects, problems linked to technological transfer or task sharing, duration of cooperation, etc.
Three scenarios for Europe's role Several other parameters will influence the selection of Moon/Mars mission scenarios, such as the dates and deadlines considered for these missions, their duration, their degree of automation and their autonomy. A simple return to the Moon would not appear to be particularly newsworthy, since it was achieved 20 years ago. If planned, it should therefore first be manned and then be presented in the framework of more ambitious missions towards Mars, for which the Moon could be used as an outpost or to conduct experiments, perform crew training or extract propellant. On the other hand, a direct mission to Mars does not seem very realistic today without preliminary experience that could be ideally gained from the Moon. A few scenarios (although there are many others) are considered here for the purpose of analysis of the part Europe may play if a manned interplanetary programme is decided (see Table 1). Scenario 1: general consensus and full international cooperation
This would be an ideal case, especially if adequate funding is assumed, in which case the dates that have been put forward for humans on Mars (2020-30) could well be achieved. Three subscenarios may again be distinguished: Scenario l(a): Mars exploration (reference scenario). The first step in
318
SPACE POLICY November 1991
The Moon and Mars: role and impacts for Europe Table 1. Summary of Europe's role in several scenarios. Scenario 1(a)
Objective Mars exploration
Cooperation Full
1(b)
Mars exploitation/colonization
Full
1(c) 2(a),2(b),2(c)
Moon colonization As for 1(a),l (b),l (c) respectively
Full Limited
3(a),3(b),3(c)
As for 1(a),1(b), 1(c) respectively
None
2p. Zgirski and M. Grimard, 'Space station building and assembly optimization', IAF9 0 - 0 9 3 , A e r o s p a t i a l e , Les M u r e a u x , France.
SPACE POLICY November 1991
European participation Participation in automatic exploration, support node and Hab/Lab modules, Participation in communication networks, launchers and orbital vehicles, and landers. Possible participation in any technological field. As for Scenario 1 (with probably different levels of participation as a function of the domain). All (possible commercial agreements with others).
this scenario would be automatic/robotic exploration of the Moon and Mars. The second step would be a test base on the Moon, supported by Earth (logistics). The third step would be the establishment of a first temporary base on Mars, with minimal infrastructure. The fourth step would be the establishment of a network of bases on Mars and an in-orbit infrastructure. The role Europe could play in such a scenario could be as follows. First, Europe has already taken part in the automatic exploration of Mars through participation in the 'Phobos', 'Mars Observer' and 'Mars '92' missions, and has also already defined three main European axes of involvement in planetary exploration: orbital science for mapping and imaging; network science using penetrators, semi-hard landers or balloons; and rover science for mobile surface exploration. Since Europe's expertise and technological competence have already been demonstrated through many satellite and probe programmes, its commitment to the field of automatic exploration may well be extended and increased. Looking at the main segments identified above, several factors may be noted. Countries such as the USA or the USSR already have much more substantial experience in space stations, long-duration flights and extra-vehicular activity (EVA) than Europe, and therefore the role Europe could play in such fields would obviously not be a leading one. However, European countries have for roughly 10 years been performing various studies in the domain of in-orbit infrastructure e and may well be in charge of, for instance, pressurized modules, for either in-orbit stations or surface bases. In the same way, a European Manned Space Infrastructure (EMSI), today scheduled to be achieved within the first two decades of the 21st century, could be used as a support node. As regards the Earth-to-orbit transportation, and in spite of the fact that the USSR, the USA and Japan also have launchers, Ariane 5 and Hermes, together with their derivatives, could play an important part for flexibility and cost reasons. This family may also be completed by transfer vehicles capable of rendezvous and currently under study for ESA, such as ATV or LOVE, as well as by escape vehicles for space stations. All the other segments are in early stages of development as regards the Moon and Mars and thus seem to remain open to European participation. Europe may thus again be present in the field of landing vehicles with derivatives of the above-mentioned spacecraft, or thanks to the competence it has acquired in several kinds of propulsion, including nuclear or ionic propulsion. Technological expertise and experience gained in communications and associated networks would also enable Europe to take part in this field. 319
The Moon and Mars: role and impactsfor Europe Nevertheless the part played by each participant will strongly depend on its degree of financial involvement in the programme and on its position in the programme organization. Scenario l(b): exploitation of Mars (optimistic scenario). Steps 1 to 3 would be the same as Scenario l(a). The fourth step would be autonomous, permanently manned industrial settlement. This scenario does not seem very credible today, since the cost of an industry on Mars would be prohibitive for the opportunities currently foreseen. There would not be major changes compared with the previous scenario as regards the role of Europe, except that the vehicles and infrastructure required would be slightly different, but without major technological differences. Scenario 1 (c) : colonization of the Moon (pessimistic scenario). The first step would be automatic/robotic exploration of the Moon. The second step would be a temporary base on the Moon, supported by Earth (logistics). The third step would be a permanently manned base, supported by Earth. The fourth step would be an autonomous permanently manned base. The conclusions as regards the role Europe may play in this scenario again remain the same as previously, except that a limited scenario would result in reduced infrastructure and reduced roles for each participant, and such missions would require fewer new developments since they could roughly be achieved with existing technologies. It may be recalled here for instance that an Ariane 5 launcher can send 22 tonnes into LEO and roughly 5 tonnes into lunar orbit (up to 9 tonnes with an already foreseen improved version), and could thus be used for instance for logistic support while heavy launchers (eg Energiya) could be used to send pressurized modules or landers. Europe could also have a significant role in surface bases if in-orbit infrastructures and heavy launchers were provided by nations which have already developed them. However, it must be noted that all the participating countries would be required to play a part in this segment, which would be the only real novelty, and again the percentage of financial participation would be a major factor. Scenario 2: limited cooperation (eg Western countries only) This scenario would lead to more critical problems of funding and development, but the previous subscenarios could be kept, though delays would be likely to occur. It does not seem that particular technological problems would arise from this limitation of cooperation. However, some experience would have to be gained, for instance as regards long-duration flights, and, considering the background of the Western countries, this task would probably be covered by the USA. Moreover, the lack of a heavy-lift launcher would probably be a handicap which would require either the development of a new expendable launcher (the US ALS or European) or the improvement of a cargo shuttle, probably under US responsibility. This does not greatly change the position of Europe itself, nor the conclusions of Scenario I as regards the European potential, but it could increase its relative part in other areas (eg transfer vehicles, surface elements, landers, rovers and communication networks).
320
SPACE POLICY November 1991
The Moon and Mars: role and impacts for Europe Scenario 3: no cooperation
This pessimistic case could very well mean the withdrawal of manned missions to Mars or their postponement to a much later date, at least for E u r o p e alone. The role of Europe in such a scenario would be obvious since it would have to achieve everything on its own. In this case, European in-orbit infrastructures, for instance, would not remain confined to support roles but would be indispensable, which would in turn require experience. The same remarks could be made for almost any of the previously identified segments. However, if Europe decided from now on to aim at this kind of situation, which is very unlikely, or was certain that it would occur, several options could be decided from the beginning. For instance, it could be decided not to design and develop a new heavy-lift launcher but rather to develop in-orbit assembly/building techniques, together with improvements to the performance of current launch means and an increase in launching flexibility (number of launch pads, ground facilities, etc). Moreover, even if no real cooperation were envisaged, commercial agreements could perhaps be considered (although this is doubtful), at least initially: it may be envisaged, for instance, to buy propellant from a non-European production unit on the Moon if any exist, or to buy a US or Soviet launcher, or to rent surface modules within already existing bases.
Impacts on current or future European programmes These impacts are of two kinds. Impacts of such missions on future programmes that will be decided after a Moon/Mars scenario is selected will of course be implemented from the beginning, while impacts on current programmes or on programmes that will be in progress at the time the decision to undertake a Moon/Mars mission will be made will depend on the degree of completion of these programmes and on the possibility of reorienting them. The major E u r o p e a n programmes that would be likely to be affected by these missions today would be mainly Ariane 5, Hermes and Columbus, as well as, to a smaller extent, the foreseen European transfer vehicle and the future space infrastructure or a possible aerospace plane. Ariane 5, for instance, would belong to the first category. Improvements are already foreseen to increase its performance or decrease its cost with more powerful engines and solid boosters, liquid boosters, improved cryogenic stage, reusable boosters or twin engines. However, it is not likely that its performance will be increased up to more than say roughly 35 tonnes in L E O without designing something radically new. The same applies to Hermes though its degree of development is lower than that of Ariane 5, to which it is, however, closely linked: derived versions used as space taxis for crews of up to 10 or as escape vehicles may be envisaged. For Columbus, several standard modules may need to be assembled if needed to form a station that would be larger than the Columbus Free Flyer and more autonomous than the Attached Pressurized Module. However, many aspects would first have to be developed, such as a large altitude control system and power generation. In this it may perhaps be considered as an intermediate case, since the ultimate
SPACE POLICY November 1991
321
The Moon and Mars: role and impacts for Europe
European space station is not scheduled to be completed before 2010 and its status would rather make it part of the last scenario. Some analyses of the impacts Moon/Mars missions would have on space stations have already been made at Aerospatiale: a station foreseen first as a laboratory to develop new technologies and to observe the Earth would have to evolve towards a transportation and support node, providing vehicle assembly, check-out and refurbishment facilities, propellant storage and housing for crews. Similar remarks could be made as regards the currently foreseen transfer vehicles, since their design status is today such that they could still be optimized in the aim of Moon/Mars scenarios; however, if these vehicles were to be launched by Ariane 5, they would already be constrained.
Conclusion Manned missions towards Moon or Mars seem to have been coming back to the foreground of the international scene for some time, and in spite of its current commitment in several major programmes, Europe should also play a part in this field, especially as it already has the right means and competence to do so. Its role would of course be a function of its degree of involvement and of the cooperation strategy adopted, as well as of the new developments that would be required. If such a programme took place, it would obviously affect existing or upcoming European elements by requiring improvements or reorientations, and would therefore greatly influence Europe's future in space.
322
SPACE POLICY November 1991