After 42 years, the National Aeronautics and Space Administration (NASA) has agreed to open its files to UFO enthusiasts concerning a 1965 incident when a space object was believed to have crashed in Pennsylvania.

The decision was a surprise since the space agency fought hard in federal court to stop the search of its archives for the documents it had about what happened on Dec. 9, 1965 in Kecksburg.

NASA apparently bowed to pressure from science fiction fanatics and New York journalist Leslie Kean, who sued for the information in 2003. Kean pressed NASA to release more information to supplement documents already made public. U.S. District Judge Emmet Sullivan denied NASA's request in March to dismiss the case. Earlier, the space agency turned over a pile of documents, which the judge said did not give sufficient information on the incident.

Witnesses had said they saw something moved from across the sky and crashed in the woods of Kecksburg. They described a metallic, acorn-shaped object about four meters high and two to four meters in diameter that landed as a "fireball." A monstrous traffic jam ensued but the soldiers promptly drove kibitzers away. They said a truck drove away a large object within hours of the incident.

The Air Force insisted that a meteor crashed in the site but did not produce physical evidence to back its claim. Later, they admitted the "UFO" was a Russian satellite but records on this were lost in the 1990s. NASA has said there was no "cover-up."