The crew chosen for the first human voyage to Mars must learn to deal with obligatory confinement and to survive amidst serious health threats during an extended period, as long as three years, say US experts in space travel. Every clear night, Mars appears, twinkling a reddish-yellow, tempting those who dream of setting foot on its surface. But behind its warm appearance is the reality of an average temperature of 53 degrees below zero Celsius and an atmosphere that consists almost completely of carbon dioxide.
The announcement in January by US President George W. Bush of a possible manned mission to the neighbouring planet was enough to set some enthusiasts to fantasize about packing their bags. The first thing is to establish a timetable for the trip, Robert Zubrin, head of the International Mars Society, told TierramÃ©rica.
However, the distance that separates Earth from Mars, as well as the dangers that await a human crew, could pose challenges that would push back the launch date. â€œThe main challenge is the length of time away from Earth: around three years. An 18-month stay (on Mars) would be required before they could lift off and come back,â€ John Hoffman, physicist at the University of Texas at Dallas and member of NASAâ€™s project Phoenix, which studies the geological history of water, told TierramÃ©rica.
In August 2003, Mars was a relatively close 56.3 million km from Earth, the shortest distance between the two in 60,000 years.Outside of the Earthâ€™s protective atmosphere, space radiation is so strong that it can remove the electrons of the atoms it hits. This could produce genetic damage to human cells. Cancer, cataracts of the eyes and damage to the central nervous system are some of the possible effects.
According to NASA, on the International Space Station (ISS), which orbits the Earth at 386 km, scientists are studying the impacts of space travel on astronautsâ€™ health. Says the Mars Societyâ€™s Zubrin, an astronaut travelling to Mars would run the same risk of cancer as if he or she stayed on Earth and smoked two packs of cigarettes a day for three years.
The National Space Biomedical Research Institute (NSBRI), which works with NASA to reduce health risks during space travel, says that flights beyond the Earthâ€™s orbit lasting more than 12 months have shown that astronauts can lose up to 20 percent of their bone mass.
This increases the risk of bone fractures and of the formation of kidney stones, due to the release of calcium from the bones. The culprit behind this phenomenon is the lack of gravity.
The experiences of the ISS have taught us the essential facts about humans remaining in outer space for long periods, says John Ira Petty, spokesman for the Lyndon B Johnson Space Centre. One lesson is that astronauts need to exercise to prevent muscular atrophy and to improve their cardiovascular functions.
But â€œa manned mission to Mars depends on budgets and the development of new technologies,â€ he said, though if these requirements were met, a mission to the red planet could be launched every 25 months. â€œWe are a long way from a manned Mars mission. Probably new crew members will not be chosen until 10 or 20 years from now,â€ Petty said. â€” IPS