Moscow ? A small piece of space junk slammed against the hull of the international space station, causing no apparent damage but startling the two men inside with its grinding, metallic sound, a Russian official said Thursday.

Officials said U.S. astronaut Michael Foale and Russian cosmonaut Alexander Kaleri were safe after the incident, which apparently did not disrupt their plans for Thanksgiving dinner.

A spokesman for the Russian Space Forces, a military branch that monitors Russia’s satellites but also keeps track of the space station, said the orbiter had collided with a piece of debris.

The spokesman, who spoke to The Associated Press on condition of anonymity, said the space forces had detected an object along the station’s orbit, and had determined it was very small and would pose no danger to the craft.

Foale said he heard something that “sounded like a metal tin can kind of being expanded and compressed. It was a noise that lasted about a second. It sounded like an impact or something.”

Russian Aerospace Agency spokesman Sergei Gorbunov said the sound might have come from some of the station’s equipment rather than a collision. He said an ensuing check found no trace of impact.

“The check made by the crew found no changes either in the equipment section or the atmosphere of the station, which would have changed instantly if the station’s skin were punctured,” Gorbunov said on NTV television.

Valery Lyndin, a spokesman for Mission Control outside Moscow, said “all the station’s systems are working normally” after the sound was reported early Wednesday.