If the prospect of spending 1,000 days up to 225 million kilometers away from planet Earth were not enough of a deterrent, you might think the killer radiation levels and enforced radio silence would put off any volunteers to travel to Mars. However, NASA has revealed it is seeing near-record numbers apply for its astronaut training program, as growing hopes of a manned mission to the red planet rekindle enthusiasm for deep space travel.
Since the successful landing of the unmanned Curiosity rover in August last year, the scientific community has begun to take more seriously a promise from US President Barack Obama in 2010 to land humans on the surface within about 20 years.
Some privately backed rival ventures are even forecasting they could get to Mars orbit as early as 2018, and NASA plans a deep space practice mission to rendezvous with a captured asteroid by 2025.
“Interest in sending humans to Mars has never been higher,” NASA’s chief administrator and former astronaut Charles Bolden told a conference in Washington on Monday. “We now stand on the precipice of a second opportunity to press forward with what I think is man’s destiny and that is to go forward to another planet.”
Within the next few weeks, NASA plans to announce which 20 new trainee astronauts it has chosen from 6,300 recent candidates — its second-highest application total since the agency was established in 1958.
“These astronauts will be among the first trained specifically for long-duration space flights,” Bolden said.
Despite sweeping US budget cuts, NASA still hopes for an annual budget of US$17.7 billion — increasingly targeted on the Mars mission as the top priority. It is seeking Congressional approval to outsource to private contractors all future rocket missions to low Earth orbit, so it can concentrate on deep space instead.
However, the three-day conference in Washington has also revealed how significant the remaining “technology gaps” are.
The one-tonne Curiosity rover was lowered to the surface of Mars from a spacecraft acting at current weight limits as a “sky crane,” yet engineers estimate a human capsule would need to weigh at least 40 times as much. NASA also needs to invent giant new solar panels — powerful enough to complete a round trip to Mars, but flexible enough to fold up into a rocket — and find ways of preventing the craft from being damaged by charged ions.
At least five unmanned supply missions will need to deliver equipment in advance and a robotic vehicle will probably drill beneath the surface to look for water for drinking and propulsion of the return trip.
The sun is likely to block communication for weeks on end and robots will probably also need to be used to help build a shelter on the surface of Mars to protect astronauts from cosmic radiation 100 times that on Earth.
Pascale Ehrenfreund, a scientist at NASA’s astrobiology institute, warned that its projections for a 1,000-day mission, including a stay of a few hundred days on the surface, currently showed an “unacceptable risk” of radiation exposure.
Notwithstanding its attempts to learn how to steer asteroids, NASA sees the Mars mission as a vital stepping stone into outer space for humanity in the long run.
“We know from looking at what happened when an asteroid hit Earth 65 million years ago that single-planet species tend not to survive,” science director John Grunsfeld said.