The Chinese military used a ground-based missile to hit and destroy one of its aging satellites orbiting more than 500 miles in space last week, an apparent test of anti-satellite technology that raised concerns about a possible arms race in space and drew sharp protests from other spacefaring nations.

The satellite-destroying test is believed to be the first of its kind in two decades by any nation, and experts say it dramatically illustrates Chinese capabilities in space and their willingness to face the certainty of broad international criticism.

“The U.S. believes China’s development and testing of such weapons is inconsistent with the spirit of cooperation that both countries aspire to in the civil space area,” National Security Council spokesman Gordon Johndroe said yesterday. “We and other countries have expressed our concern regarding this action to the Chinese.”

In addition to introducing a renewed military dimension to space, the destruction of the Chinese satellite created a large “debris cloud” that can seriously damage other satellites in nearby orbit, and possibly even spaceships passing through the region on their way to the moon or beyond.

Analysts said that based on computer models, as many as 300,000 pieces of debris may have been created with the explosion. While many will be very small, they said, hundreds will be large enough to create potentially serious problems. Both America and the former Soviet Union tested anti-satellite technology in the 1980s, and America shot down one of its orbiting satellites in 1985. Partially as a result of the debris problem, both sides stopped the practice.

The Chinese test, which was first reported online by the magazine Aviation Week and Space Technology, comes at a time of heightened tensions between America and China regarding space. China is leading an effort in the United Nations to set up an international conference that would address what many consider to be an imminent space arms race.