Introduction

In January 2004, President Bush announced a new Vision for Space Exploration, which has refocused NASA's objectives towards human missions to the Moon and Mars, and the European Space Agency's Aurora Programme has established similar objectives for Europe. Most recently, in May 2007, 14 of the World's space agencies have published the Global Exploration Strategy: Framework for Coordination which provides a global vision for future space exploration, focussing on planetary destinations where humans may one day live and work. It is in this new political context that the UK must soon decide whether, and to what extent, it wishes to participate in these exciting endeavours. These issues were considered by the UK Space Exploration Working Group in September 2007, which recommended increased UK involvement in space exploration and full participation in the Global Exploration Strategy.

While the subject of human space exploration is currently controversial in the UK, with many scientists believing that the resources would be better invested in robotic missions, it can be argued that human beings are uniquely qualified to undertake several key scientific investigations in the space environment (ranging from life and physical sciences research in microgravity, to geological and biological fieldwork on planetary surfaces). This potential has in fact been recognized by three recent studies. Firstly, in 2003, the independent Microgravity Review Panel examined the scientific merits of microgravity research to be conducted on the International Space Station (ISS) and concluded that the potential benefits are sufficiently great that the UK should participate in this programme. Secondly, in May 2004, the Cross Research Council Report identified a wide range of potential scientific benefits from participation in the human spaceflight aspects of the Aurora programme, and explicitly called for a re-examination of UK policy in this regard. Finally, and most authoritatively, in October 2005 the Royal Astronomical Society issued it's Report of the Commission on the Scientific Case for Human Space Exploration , which drew attention to wide ranging scientific and cultural benefits of human space exploration.

In a European context, in 2008 the European Science Foundation issued its Report on a Science-Driven Scenario for Space Exploration, which also identified many scientific benefits of HSF and argued for continued European involvement in human space exploration in the context of the Global Exploration Strategy.

We summarise the arguments in support of human space exploration below (further details can be found in the bibliography):

Research in Microgravity

The microgravity environment of low Earth orbit provides unique opportunities for research in the life sciences (including human physiology and medicine), materials science, and fundamental physics. Further progress in these areas will rely on the unique capabilities of the International Space Station. Although the UK has so far opted out of microgravity research on the ISS, the potential scientific benefits are well documented and were recognized by the Microgravity Review Panel which noted that:

Probably the most important scientific benefits of microgravity research will accrue to the life sciences where research in the space environment has demonstrated the potential to provide unique insights into such areas as gene expression, immunological function, bone physiology, and neurovestibular and cardiovascular function. These areas are important for understanding a range of terrestrial disease processes (e.g. osteoporosis, muscle atrophy, cardiac impairment, and balance and co-ordination defects), and as such have potential medical applications here on Earth. The UK has a growing space biomedicine community well-placed to benefit from, and contribute to, these important research fields.

Space Astronomy

From almost the very beginning of the space age, astronomy has benefited from being able to place instruments above the obscuring effects of Earth.s atmosphere. Most of these observations have been performed by robotic spacecraft, without human intervention. However, one of the principal lessons from the most successful of these instruments, Hubble Space Telescope (HST), is that access to a human spaceflight infrastructure can greatly extend the life, and enhance the efficiency, of space-based astronomical instruments. Since its launch in 1990 the HST has been serviced by four Space Shuttle missions, and a fifth now appears likely. As documented by a recent report of the US National Research Council on the Assessment of Options for Extending the Life of the Hubble Space Telescope, without this human intervention the HST would have been a much shorter lived, and far less scientifically versatile, instrument than it has in fact turned out to be.

There are important lessons here for the future of space astronomy. A number of large space-based telescopes are currently being planned (including the James Webb Space Telescope and ESA's Darwin project, in both of which the UK has an interest), and the HST experience teaches us that the operational lifetime, and scientific productivity, of these instruments are likely to be enhanced if a human spaceflight infrastructure exists which is able to maintain and upgrade them. In the longer term, astronomy may also benefit from a renewed human presence on the Moon, as the lunar surface provides an excellent location from which to perform astronomical observations across a wide range of wavelengths (for example see the document on Astrophysics Enabled by the Return to the Moon produced by the Space Telescope Science Institute.

Planetary Exploration

The Apollo programme clearly demonstrated the scientific value of astronauts as explorers of planetary surfaces, principally because they bring agility, versatility and intelligence to exploration in a way that robots cannot. Although it is true that humans will face many dangers and obstacles operating on other planets, mostly due to their physiological limitations when compared to robots, the potential scientific returns (resulting from rapid sample acquisition, the ability to integrate widely disparate data and past experience into a coherent picture, and the on-the-spot ability to recognise observations to be of importance even if they relate to phenomena not anticipated in advance) is more than sufficient to justify employing astronauts as field scientists on other planets. These scientific advantages of having human explorers on the Moon and Mars were recognized by the Royal Astronomical Society's Report of the Commission on the Scientific Case for Human Space Exploration , which concluded that:

In the specific case of lunar exploration, these arguments have recently been reiterated by the US National Research Council's report on The Scientific Context for the Exploration of the Moon which identified a number of areas where a renewed human presence on the Moon would yield scientific benefits not otherwise attainable. There is little doubt that the UK planetary science community would benefit from involvement in these exciting activities.

Science Education

Space exploration is inherently exciting, and as such is an obvious vehicle for inspiring the public in general, and young people in particular, to take an increased interest in science and engineering. This was explicitly recognized in the conclusions of the UK Microgravity Review Panel:

A similar point was made by the RAS Report, which concluded that:

Although these arguments have so far fallen on deaf political ears in the UK, such inspiration must be of value to any modern, knowledge-based economy, especially at a time when the number of young people opting for careers in science and engineering is falling.

Industry

Human spaceflight is technically very demanding, and this is indeed one of the reasons why it is so expensive. However, for this very reason, engaging in human space activities must necessarily act as a stimulus for employment, skill development, and technical innovation in the participating industries. This expansion of technical capabilities is likely to find applications in other areas of the wider economy. Moreover, under the ESA principle of juste retour, expenditure incurred as part of ESA's human spaceflight programmes would be invested back in UK, thereby stimulating UK industrial innovation and protecting UK jobs.

Furthermore, when considering the potential economic benefits of ambitious space projects, it is necessary to consider the beneficial multiplier effect on the wider economy resulting from employment in key industries. Human space exploration may be expensive, but the money itself does not leave the Earth. Rather, it stays on the ground where it can help stimulate economic activity. A detailed study of the wider economic effects of space expenditure was performed by Bezdek & Wendling (1992), who traced the influence of NASA.s 1987 procurement budget of $8.6 billion dollars on the US economy. An important result of this study was that while the initial beneficiaries of NASA procurement were the large aerospace companies, much of the economic benefits filtered down through layers of sub-contractors to the industrial heartland of America. As noted by Bezdek and Wendling in the conclusion of their study:

Under current policy, UK industry is effectively excluded from these potential benefits.

International Cooperation

Space exploration provides a natural focus for international cooperation, as indicated by the collaboration of some 15 nation states (currently excluding the UK) in the construction and operation of the ISS and the recently formulated Global Exploration Strategy. In trying to build a stable geopolitical environment on Earth, it must be desirable to increase the range and depth of such collaborative endeavours. Human space exploration is especially, and perhaps uniquely, well-suited to enhancing a sense of global solidarity owing to its globally high media profile. From this point of view, it would seem to be desirable that a major economy such as the UK is seen to be .pulling its weight. in the international exploration of space.

Conclusions

The United Kingdom is the only major industrialised economy that has consistently declined to participate in human space exploration, and the reasons for this anomalous situation need to be addressed. Present UK government thinking on the subject was spelt out by the Science Minister, Lord Sainsbury, in a speech at the Royal Society on 17 October 2001:

This is an interesting, if rather muddled, justification for present policy. It acknowledges that 'political and cultural' benefits of human spaceflight exist, but it implies that these are not in themselves sufficient to justify investing in it. Instead, Lord Sainsbury.s statement attempts to justify UK policy regarding human spaceflight by its alleged lack of scientific benefits.

However, as pointed out above, clear scientific benefits of human space exploration can in fact be readily identified. Given that participation in human space activities would also be inspiring UK school children, supporting UK industry, and making a positive contribution to international cooperation, there appears to be a strong case for re-examining UK policy this regard. This is especially so given the new international context provided by ESA's Aurora programme, and the US Vision for Space Exploration, where UK participation would provide wide-ranging scientific, industrial and educational benefits that cannot obviously be attained in any other way.

Select Bibliography

In addition to giving the references cited in the text, the following bibliography also provides a selected list of recently published articles which advance the scientific and cultural arguments in support of human space exploration:

Ball, A.J. and Crawford, I.A., Which Way to the Moon?, A Report on NASA's Exploration Strategy Workshop, Washington, D.C., April 2006, Astronomy and Geophysics, 47, 4.17-4.19 (2006).

Bezdek, R.H. and Wendling, R.M., "Sharing Out NASA's Spoils", Nature, 355, 105-106, (1992).

Close, F., Dudeney, J., Pounds, K., "Report of the RAS Commission on the Scientific Case for Human Space Exploration, Royal Astronomical Society, (2005).

Cockell, C.S., "The Value of Humans in the Biological Exploration of Space", in: ``The Scientific Case for Human Space Exploration'', proceedings of an RAS Specialist Discussion Meeting published in a Special Issue of Earth, Moon and Planets, 94, 233-243, (2005).

Crawford, I.A., ``To Still Boldly Go'', first published in the political and cultural magazine Prospect , 84, 18-19, (March, 2003).

Crawford, I.A., ``The scientific case for renewed human activities on the Moon'', Space Policy, 20, 91-97, (2004).

Crawford, I.A., ``Human exploration of the Moon and Mars: implications for Aurora'', Astronomy & Geophysics, 45(2), 28-29, (2004).

Crawford, I.A., ``Towards an Integrated Scientific and Social Case for Human Space Exploration,'' Earth, Moon and Planets, 94, 245-266, (2005).

Crawford, I.A., ``The Astrobiological Case for Renewed Robotic and Human Exploration of the Moon'', Internat. J. Astrobiol., 5, 191-199, (2006).

Crawford, I.A., ``Swords to Spaceships'', first published in the political and cultural magazine Prospect , 131, 14-15, (February, 2007).

David, L., ''Return to the Moon'', Aerospace America, January 2009, pp. 30-35, (2009).

European Science Foundation, Report on a Science-Driven Scenario for Space Exploration.

Fong, K., "Human Spaceflight in the UK: The Cost of Non-Participation", in: ``The Scientific Case for Human Space Exploration'', proceedings of an RAS Specialist Discussion Meeting and published in a Special Issue of Earth, Moon and Planets, 94, 169-176, (2005).

Garvin, J.B., "The Science Behind the Vision for US Space Exploration: The Value of a Human-Robotic Partnership," in: ``The Scientific Case for Human Space Exploration'', proceedings of an RAS Specialist Discussion Meeting publis$ Special Issue of Earth, Moon and Planets, 94, 221-232, (2005).

Livio, M., Astrophysics Enabled by the Return to the Moon, summary of a workshop held at the Space Telescope Science Institute, (November 2006).

Rennie, M.J., "Aurora could light the way to a renewal of British space biology", Research Fortnight, 209, (10 March, 2004).

Rennie, M.J. and Narici, M.V., "The Case for Support of Manned Spaceflight as a Platform for Research in Sarcopenia and Osteopenia", in: ``The Scientific Case for Human Space Exploration'', proceedings of an RAS Specialist Discussion Meeting published in a Special Issue of Earth, Moon and Planets, 94, 177-183, (2005).

Space Studies Board, US National Research Council, "The Scientific Context for Exploration of the Moon - Final Report", (2007).

Spudis, P.D., "The case for renewed human exploration of the Moon," in: ``The Scientific Case for Human Spaceflight:'' Proceedings of a symposium held to commemorate the 40th anniversary of human spaceflight, and published in a special issue of Earth, Moon and Planets, 87(3), 159-171, (2001)

Stern, S.A., Ex Luna Scientia , The Space Review, (3 October 2005).

Wakeham, B., Sykes, R., Williams, P., Garwood, S., Recommendations of the Microgravity Review Panel, (2003).

Document prepared and maintained by:

Dr Ian Crawford (Senior Lecturer in Planetary Science and Astrobiology, Birkbeck College London)

Dr Kevin Fong (Senior Lecturer in Physiology, University College London, and Director of the Centre for Aviation, Space and Extreme Environment Medicine)