HOUSTON: Behind 18 inches of concrete in stainless steel cabinets flushed with pure nitrogen rests a material rarer than gold, more valuable than diamonds.

Not even Nasa curator Gary Lofgren knows both combinations to the Johnson Space Center’s vault that contains 600 pounds of lunar rocks and soil.

Of late, Lofgren has noticed something unusual — there’s been a run on moon dirt. Gram by precious gram, he’s been doling out samples to researchers around the world eager to study the desolate orb again.

Thirty-four years after the last Apollo astronaut walked on the lunar surface, a new space race is underway.

It will be a long race, with humans unlikely to set foot on the moon again in the next 10 to 15 years. But countries are gearing up to take their first steps.

India’s 20,000 space workers are readying a lunar orbital mission set for 2007. Japan plans to send a robotic rover to the lifeless rock by 2013, and the European Space Agency has a probe, SMART-1, orbiting the moon.

Although many countries are talking about sending people to the moon, only two, the United States and China, have set dates for manned lunar landings. Nasa says its next manned mission will be as early as 2018; China says it wants to land ‘taikonauts’ — as Chinese astronauts are called — as early as 2017.

“There is a lunar armada” on the way back to the moon, said James B. Garvin, head of Nasa’s Lunar Reconnaissance Orbiter project, scheduled to lift off in 2008.

It’s an unlikely renaissance of lunar exploration after decades of sending robots to distant planets while human explorers busied themselves building a space station in low-Earth orbit.

Each country is going for its own reasons — some commercial, some strategic, some for national pride. But if the plans come to fruition, the moon could become a busy extraterrestrial outpost for scientists, engineers and possibly ordinary citizens in the coming decades. It would also serve as a vital way station for man’s long-dreamed-of trip to Mars.

Leading the way is the only country that has set foot there before, the United States.

Two years from now, Nasa will begin launching probes to search for landing sites and potential water sources at the moon’s south pole. Work is underway on new generation lunar projects, including a souped-up rover and a $38-million project to extract breathable oxygen from moon dust.

All this has gotten Nasa’s workforce, which has been demoralized by the frustrations and tragedies of the ill-fated space shuttle programme, fired up in ways it hasn’t been since the 1960s. But there are plenty of doubters.

Why bother with the moon? The US has been there. Six times. On each occasion, explorers have found the same barren world — a place of ‘magnificent desolation’, in the words of Apollo astronaut Buzz Aldrin.

Visionaries such as Gregg Maryniak, director of the James S. McDonnell Planetarium in St. Louis, have little patience with those who say, ‘been there, done that’ about the moon.

“That’s like saying you’ve seen New York when you changed planes at JFK.”

Bouncing along a patch of Texas flatland at the Johnson Space Center, Nasa engineer Joe Kosmo steered his pickup truck onto a field covered with tangled tufts of grass.

Kosmo hopped out and began tramping into the weeds.

“It was right here,” he said, gesturing at a small sign that reads: ‘Wildflower Preserve’.

At the height of the moon race in the 1960s, the Army Corps of Engineers dug a six-acre faux lunar landscape here, complete with craters. Apollo Astronauts in spacesuits test-drove the lunar rover and clambered over large rocks to prove they could handle the harsh environs of the moon.

“A lot of people spent a lot of time here,” Kosmo said.

The country was younger and bursting with energy when President Kennedy inaugurated the race to the moon in May 1961.

“No single space project...will be more exciting or more impressive to mankind...and none will be so difficult or expensive to accomplish,” Kennedy said. A month earlier, Soviet cosmonaut Yuri Gagarin had become the first person in space when he orbited Earth in his Vostok 1 spacecraft. It was the latest in a string of firsts notched by the Soviet space programme, beginning with the 1957 launch of Sputnik, whose distinctive ‘beep, beep, beep’ broadcast sent American politicians into a frenzy.

Slowly, America began to catch up. It was a heady time, fired by patriotic zeal and steeled by tragedies. At least four Soviet and three American astronauts died in the moon race.

It took seven years and $150 billion in today’s dollars to get there. At 1:17pm PDT on July 20, 1969, astronaut Neil Armstrong announced: “Houston, Tranquillity Base here. The Eagle has landed.”

Several hours later, the spectral image of a man appeared on television slowly descending the ladder from the Apollo 11 lunar module.

The US sent five more missions. But by the end of the Apollo programme in 1972, the passion for the moon had faded. American television curtailed its coverage, more enamoured of Watergate and other earthly concerns. Twelve people walked on the lunar surface.

Space workers dispersed to other programmes, budgets shrank and the moon once again was just a silver orb in the night sky, inspiration to poets and songwriters rather than engineers.—Dawn/Los Angeles Times News Service