China says it will launch its first astronauts into space later this year. Beijing is hoping the manned space program will boost commerce, science, and security. But, those benefits come at a price.

Late in December, China launched the un-manned Shenzhou Four space capsule, which officials say was a "dress rehearsal" for a manned space mission later this year, perhaps as early as October.

China has trained 14 of its top fighter pilots to be astronauts. A successful flight by one of them would make China the third nation in the world to independently send humans into space, after the United States and the former Soviet Union.

While Beijing started its manned space program long after the Russians and Americans, author and former U.S. space agency engineer Jim Oberg says China will quickly catch up.

"They are very quickly achieving capabilities and will be a serious player," he said. "They are only the junior partners for a few more months or a few more years, but they will be partners in space [exploration]."

Changes in political priorities meant China's manned space program grew in fits and starts since its beginnings in the 1970s.

The expensive program languished in the 1980s, but China's growing prosperity allowed work to resume in 1992 with the first test of a Shenzhou space capsule in 1999.

China has always said it is interested in peaceful uses of space, but security is also an important consideration. Key Chinese space officials say a vigorous space program keeps China from being bullied by other advanced space-faring nations.

Federation of American Scientists researcher Charles Vick says the intense effort needed to put a human in space will help China reap down-to-earth benefits in military, commercial and scientific areas.

"If you don't push the basic sciences to push the basic technologies to drive one's national economy and also provide for the national security of a nation, you are really undermining your national economy [and] in a lot of respects, the very foundation of your nation," he said.

Experts say manned space flight leads to improvements and inventions in many different fields, including better computers, improved light-weight materials, and new kinds of tools.

Beijing's military may get better communications, improved ways to spy on enemies, and more effective methods for commanders to move units around on future high-tech battlefields.

Chinese authorities believe the prestige of successful manned space flight will help it attract more international customers for its satellite launch business and other high-tech industries.

But the author of a major book on China's space program says the most important benefit is the training and experience an entire generation of scientists and engineers will get from tackling the incredibly difficult problems of manned space flight.

According to Professor Joan Johnson-Freese of the U.S. Naval War College, the excitement of a manned space program helps attract the country's brightest students to demanding technical fields that have the potential to boost the nation's economy.

But these benefits are not cheap.

Foreign space experts say overall Chinese spending for space programs has grown recently and is now probably larger than the Russian effort, but still only a fraction of the U.S. space budget.

The president of the company that builds the Shenzhou capsules, Zhang Qingwei told a Chinese newspaper that Beijing has spent about $2.3 billion on its manned space program in recent years.

Analysts say its impossible to be sure of details in China's secretive space program, but guess China spends about two billion dollars overall on manned and unmanned programs each year.

Whatever the price, the spending comes at a time when China's government must make some tough financial choices. Experts say between 40 and 100 million people fall below China's poverty line - between four and 10 percent of its population. The nation's banks are groaning under the weight of bad loans, and many state-owned enterprises are collapsing, throwing tens of millions of people out of work.