CAPE CANAVERAL, Fla. (AP) _ NASA has delayed Atlantis' upcoming flight to the Russian space station by 1 1/2 months because of rocket problems, leaving American astronaut Shannon Lucid stuck in orbit.

Space shuttle managers decided Friday to replace Atlantis' two solid-fuel booster rockets and to bump the docking mission to mid-September.

Atlantis now will lift off around Sept. 15 to the Russian space station Mir, rather than the previously scheduled July 31. Lucid has been living on Mir since March and was supposed to leave via Atlantis in early August.

NASA officials say Lucid has plenty of supplies for another six weeks aboard Mir. And in an interview earlier this week, Lucid said she took along lots of books just in case something like this happened.

``Everyone is in concurrence that Shannon is in good shape and she's prepared to go longer,'' said Frank Culbertson, director of NASA's shuttle-Mir program. She'll have spent six months in orbit by the time Atlantis comes to get her.

Hot gas leaked into joints on both booster rockets of Columbia last month, most likely because of a new adhesive and cleaning agent. The same adhesive and cleaner were used in Atlantis' boosters.

None of the O-ring seals in Columbia was damaged, and the crew was in no added danger in the June 20 launch. But because engineers still do not fully understand the leakage, NASA opted for repairs on Atlantis.

The old adhesive will be used for the replacement boosters.

``Any time we get gases in the joints that are unexpected we're concerned,'' said shuttle manager Tommy Holloway.

Gas leaked through a joint in one of Challenger's booster rockets shortly after liftoff in 1986, destroying the shuttle and killing all seven crew members. This time, there's nothing wrong with the joint itself and it does not need to be redesigned, Holloway said.

NASA recently switched adhesives in these joints because the old methyl-based material was discontinued because it was environmentally unsafe. There's enough of the old glue left to outfit boosters for another two years if necessary, Holloway said.

Atlantis was moved off the launch pad and back into the hangar earlier this week because of Hurricane Bertha. The shuttle will remain in the hangar for the repairs.

The delay means that all of Atlantis' other docking missions over the next year or so will be bumped by about six weeks.

Lucid, 53, a biochemist and mother of three grown children, will continue to perform science experiments aboard the station.

She will break the U.S. space endurance record of 115 days on Monday. The record was set last year aboard Mir by NASA astronaut Norman Thagard.

Earlier in the week, NASA ruled out the possibility of using a Russian Soyuz capsule to return Lucid to Earth.

Lucid's two Russian crewmates also are having an unexpectedly long mission. A funding shortage back home is keeping them in orbit until late August, more than a month longer than planned.