WASHINGTON – A new race to the moon is under way, and the United States is lagging behind a swarm of foreign competitors.

A European spaceship, Smart-1, is due to enter lunar orbit Monday night. Four other moon missions – two Japanese, one Chinese and one Indian – are planned for launch in the next three years.

But the next American spaceship to visit the moon won’t go up until 2008 at the earliest. That trip would be the first step toward President Bush’s ambitious call to send humans to Mars a generation from now, but even the moon-shot depends on approval from a skeptical Congress.

The six lunar ventures planned for this decade are all unmanned orbiters. None would attempt to land robots or humans on the moon’s surface, but they would study it from afar with scientific instruments.

Bush’s plan wouldn’t return flesh-and-blood earthlings to the moon’ surface until at least 2015. That would be 43 years after the last Apollo astronaut came home from the moon.

Moon enthusiasts deplore the delay. “It’s an embarrassment,” said Alan Binder, a planetary scientist and founder of the Lunar Research Institute in Tucson, Ariz. “We’ve wasted almost four decades. … It’s heart-breaking.”

Now Mars is the glamour target, but scientists think there’s still much to be learned from exploring the moon with robots or humans.

The upcoming missions, if they succeed, would provide much greater detail about the moon’s structure, gravity and magnetism. Their sponsors hope to identify potentially valuable resources that could support a permanent moon base and a way station for voyages throughout the solar system.

“The more people are doing things in space, the better for everybody,” said Paul Spudis, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. “The data these missions collect could be of value to us and other nations. It’s win-win for everybody.”

Here’s a quick look at the foreign moon missions:

• Smart-1, a project of the European Space Agency, was launched in September 2003. It’s taking 14 months to reach the moon – the U.S. Apollo missions took four days – because it’s using an experimental propulsion system, called an ion drive, which starts very slowly and gradually accelerates to a high speed. It requires little fuel and is being tested for use in extremely long missions in outer space.

Smart-1 is a square box, measuring about 3 feet on a side and weighing about 800 pounds. Inside are three toaster-sized instruments to study the chemical makeup of the moon in X-rays, infrared light and ordinary light.

• Japan plans two lunar visitors but has been having trouble getting them off the ground. The first, a 1,200-pound orbiter called Lunar-A, originally was scheduled to take off in 1999, but has been delayed repeatedly by problems with the launch rocket. It’s now slated to go up sometime next year.

After settling into a 1,200-mile-high orbit, the spaceship will fire two missile-like penetrators that will drill 1 or 2 yards deep into the lunar surface, one on the side facing Earth, one on the back side. The penetrators will relay data on possible moonquakes and the nature of the moon’s core.

In 2006, Japan hopes to launch a more ambitious, 4,400-pound package of three satellites called Selene, the Greek name for the moon. The main orbiter will carry 13 scientific instruments to study the origin and evolution of the moon. It will spin off two smaller satellites, one to relay signals from behind the moon and the other to measure the moon’s wobble as it circles the Earth.

• The Indian Space Research Organization plans to launch Chandrayaan-1, Hindi for “moon voyage,” in September 2007. The 1,200-pound orbiter is to circle the moon, 60 miles above the surface, for at least two years.

• China, which launched its first man into Earth orbit in October 2003, plans to send up a lunar orbiter in 2007. It’s named Chang-e, after a Chinese story about a fairy that flew to the moon.

The Chinese space agency announced last summer that it will attempt a robotic soft landing on the moon in 2010 and a manned landing by 2020. The European Project Aurora has a goal of a manned landing on Mars by 2033, about the time the United States might be doing the same.

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