The US space agency has confirmed that it is carrying out feasibility studies to asses whether astronauts could be sent permanently to the red planet, or its moons, to establish human colonies under the ambitious project called the "Hundred Years Starship".

The astronauts would be sent supplies from Earth on a regular basis but they would have to become self-sufficient as soon as possible. The astronauts would have to embark on the mission knowing that they would never return to earth as the cost of returning would make the project prohibitively expensive.

Speaking at a conference in San Francisco, Pete Worden, Director of NASA's Ames Research Centre, recently said his division has received one million pound funding to start work on the project.The research team has also received an additional USD 100,000 grant from NASA, he said.

"The human space programme is now really aimed at settling other worlds. Twenty years ago, you had to whisper that in dark bars and get fired," he was quoted as saying by MSNBC.

"You heard it here. We also hope to inveigle some billionaires to form a Hundred Year Starship fund."

Worden said he has discussed the potential price tag for one-way trips to Mars with Google co-founder Larry Page, telling him such a mission could be done for USD 10 billion.
"His (Page's) response was, 'Can you get it down to USD one or two billion?' So now we're starting to get a little argument over the price," he said.

Depending on the position of Mars in its orbit around the Sun, its distance from Earth varies between 34 and 250 million miles. NASA's Phoenix was the most recent unmanned mission to Mars which launched in August 2007 and landed on the planet's north polar cap in May 2008.

Experts say a nuclear-fuelled rocket could shorten the journey to about four months. Of all the planets in the solar system, Mars is the most likely to have substantial quantities of water, making it the best bet for sustaining life. But it is a forbidding place to set up home.

Temperatures plummet way below freezing in some parts. The thin atmosphere would be a problem as it is mostly carbon dioxide, so oxygen supplies are a must. Worden also suggested that new technologies such as synthetic biology and alterations to the human genome could also be explored ahead of the mission.

He also said that the mission should visit Mars' moons first, where scientists can do extensive telerobotics exploration of the planet. He claims that humans could be on Mars' moons by 2030, the Daily Mail reported.

The announcement comes as a new study, published in the Journal of Cosmology, claimed that a human mission was technologically feasible and was cheaper returning astronauts to earth.It also said the costs of safely returning a crew would eat up the majority of such a mission's budget.