• Satellite hopes to map surface for rare helium 3 • Critics say cash is wasted while millions go hungry

It will be a small step for mankind, but a giant leap forward for India. In a boost to national prestige, the country will launch its first unmanned moon mission tomorrow - blasting its Chandrayaan satellite into space from an island off the Bay of Bengal, using a domestically produced rocket system. In doing so, it will match Japan, which in 1990 became the first Asian nation to send a satellite to orbit the moon, signalling the possibility of a race for mineral wealth on the lunar surface.

If all goes to plan, India's tricolour flag should be drifting down towards the freezing, airless lunar surface as dawn breaks over the subcontinent on November 11.

The 239,000-mile journey is not straightforward - it took the Americans and Russians almost two decades to master it, from the moment space exploration was born. Once above the Earth's atmosphere the launch vehicle's thrusters will have to manoeuvre and fire the Chandrayaan I rocket with precision.

If all goes to plan, the satellite, weighing half a tonne, will enter a lunar orbit some 62 miles above the moon's surface on November 8 and begin its two-year mission to map the moon in 3D, survey its surface for mineral wealth and start its 11 hi-tech probes, including five from the US, Sweden, Japan, Germany and Bulgaria.

One of India's aims in reaching the moon is the possibility of harvesting helium 3, a key fuel for nuclear fusion. Although fusion is not commercially viable today, scientists say it one day will be, and that once it is a fuel supply will become a problem, as the Earth is believed to have only 15 tonnes of helium 3. The moon is thought to contain up to 5m tonnes.

Officials at the Indian Space Research Organisation (Isro) remain tight-lipped about the possibility of a lunar land grab. UR Rao, a former director of Isro, was less circumspect, pointing out that the moon might have "enough [helium 3] to produce energy for 8,000 years". This view echoes that of the head of China's Chang'e project, who told the China Daily in 2006 that "each year three space shuttle missions could bring enough [helium 3] for all human beings across the world".

Last month, a Chinese astronaut completed a 15-minute space walk for the first time. However, India has big ambitions. There are proposals to put the first Indian into space by 2014 and to launch a manned lunar mission by 2020 - four years ahead of China's target date.

The Indian agency's next step is to launch a second unmanned lunar mission in 2011, comprising an orbiting spacecraft, a lander and a moon-rover built with Russian help.

The Chandrayaan mission, at a time of economic belt-tightening, has sparked a national debate about whether a country with hundreds of millions of poor people can afford to play catch-up in the skies.

S Satish, director of public relations at Isro, said that the Indian cabinet had given the go-ahead for the second mission in 2011, but other missions awaited approval.

"We have to consider the costs for a [manned] moon mission. Even with our low costs it will be billions of dollars. You need a good reason to send someone to the moon for that amount," Satish said.

Earlier this year India was ranked by analysts at Futron, a hi-tech consultancy, as only a fraction behind China in global space competitiveness rankings, and well ahead of Japan, Israel and Canada. It is also building a low-cost, hi-tech base. China's Chang'e I cost nearly double India's Chandrayaan I bill of $86m.

This thriftiness was born of necessity. With an annual budget of about $1bn - less than a tenth of Nasa's - Isro has to do a lot with little.

Until now India's space agency has concentrated on putting satellites in orbit. It has 11 communications satellites, using them to bring education and healthcare to remote villages via tele-links with schools and hospitals in cities.

"The whole thrust of [India's space programme] has been to get real benefits," said Gopal Raj, author of Reach For The Stars, a book about the country's rocket programme. Raj pointed out that the Madras Institute of Development Studies recently calculated that for every rupee spent on the space programme, two were generated in "indirect and direct returns".

Critics say that the space mission is a cover for an exercise in "national military-industrial ego".

Ominously, earlier this year India's chief of army staff spoke openly of his fears about China's military space programme, and stressed the need for India to accelerate its own.

"Let's face it we have an arms race here," said Praful Bidwai, a long-time critic of the space programme. "Rockets that can be used to fire satellites can be used for nuclear warheads, too. India could be spending the money on getting clean drinking water to the poor, get food in their belly. Instead it chooses to blast its way into a space race."

Reach for the stars

US Nasa put Neil Armstrong on the moon in 1969. Plans include a return manned trip to the moon by 2020.

China Completed its first manned space flight in 2003 and launched a lunar satellite in October last year. This year, Zhai Zhigang became the first Chinese to walk in space. Ambitious plans include its own space station.

Russia First to launch a satellite in 1957, and four years later launched the first human into space.

Europe European Space Agency's Ariane rocket programme became a world leader in commercial space launches in the 90s. Plans a mission to search for signs of life on Mars in 2016.

Japan First ever minister of space development appointed this year.

• This article was amended on Thursday October 23 2008. China was not the first Asian nation to send a satellite to orbit the moon, as we said. Japan was the first, in 1990. This has been changed.