Near-Term Extended Solar System Exploration

Abstract

Any discussion of long-duration space flight is of necessity a multidisciplinary discussion. It is of little value, for example, to discuss psychological issues as if they existed independently of engineering, sociological, physiological, and even political and economic issues. Simply put, there is no sense in discussing flights to the outer planets to be conducted at this time because it is not psychologically or physiologically possible. As an example, recently the Jet Propulsion Laboratory (JPL), in conjunction with the European Space Agency (ESA), sent the Cassini/Huygens probe to the planet Saturn and its moon, Titan. Given the resources available at the present time, that journey took 7 years. That would mean a 14-year round trip for a human space crew with no time at the destination. This is not physiologically possible, and it would be psychologically absurd. Yet humankind dreams of exploring the entire solar system, planets, moons, asteroids, and comets. Given that all of the disciplines mentioned above overlap in their involvement with human space flight, this chapter examines the promise of near-future long duration spaceflight from a multidisciplinary point of view.

This chapter explores psychology’s contributions to understanding human performance in space, with emphasis on the role of the autonomic nervous system. We consider what data we have about how long explorers in situations of high risk, crowding, lack of privacy, the inability to leave, and sometimes great discomfort, can be away from home, family, and life as we normally know it, and recover to live normal lives. After finding evidence to support a psychological benchmark duration, the chapter examines technology now in serious development that would make such a flight possible, using trips to Mars and Saturn as examples.

But even meeting the psychological benchmark does not address the physiological debilitation of such an extended period of weightlessness. The chapter thus examines a potential physiological “deal breaker,” bone demineralization, as well as current active research that suggests that this critical problem is in the process of being understood and solved. After proposing two promising solutions for bone demineralization, the chapter suggests that near-term spaceflight to the outer planets is reasonable to expect. The chapter closes by considering the advantages of returning to the Moon as a step toward exploratory missions to Mars, as well as the value of including humans in future missions to asteroids.