The cockpit tape recording from Challenger moments before it exploded cannot be withheld from the public because of privacy considerations, a federal judge ruled yesterday.

The decision by U.S. District Court Judge Norma H. Johnson came in a suit brought by The New York Times after the National Aeronautics and Space Administration refused last year to release the tape under a Freedom of Information request.

NASA released a transcript last July, and agency lawyers said release of the tape itself would feed the "morbid fascination" of the media while inflicting grief on the survivors of the seven Challenger astronauts "because it would subject them to hearing the voices of their loved ones."

"The court concludes . . . that the request tape does not come within the scope of Exemption 6 and that it must therefore be released under the mandate of the {Freedom of Information Act}," Johnson said.

Exemption 6 protects from disclosure "personnel and medical files and similar files the disclosure of which would constitute a clearly unwarranted invasion of personal privacy."

To bolster their case, NASA attorneys had given Johnson sealed affidavits from members of the astronauts' families opposing the release, but Johnson ordered the material returned unopened.

"I think it's an important decision," Times lawyer Timothy Dyk said.

"The judge said that because the tape didn't include anything personal to the astronauts or their families, there is no ground for it coming under the exemption," Dyk said.

Dyk argued last month that the recording should be released so the public could hear the inflections in the astronauts' voices and to determine whether the tape captured any unusual sounds at the time the shuttle exploded. Dyk also said the tape would allow the experts to determine whether any cockpit noises were recorded after the explosion, which could show whether the astronauts were conscious of their impending deaths.

In the transcript released earlier, pilot Michael J. Smith uttered "Uh-oh" in the moment the shuttle lurched and blew apart, 73 seconds after launch. There were other indications that the astronauts may have been aware of their plight.

Edward A. Frankle, NASA deputy general counsel, said his office had not seen the opinion and added that the agency, with the Justice Department, will discuss an appeal. They have 60 days to make the decision, he said.

The tape was recovered from the Atlantic Ocean after the shuttle exploded.

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