NASA Tuesday delayed the launch of Columbia until late next week because of a rash of last-minute glitches: two different computer problems and a renewed concern over fuel temperature sensors.

Columbia was supposed to have blasted off at 8 a.m. EDT Wednesday on a nine-day biomedical research mission with seven astronauts, 30 rats and 2,478 tiny jellyfish.Now, the earliest Columbia will lift off is late next week, probably May 31 or June 1, said NASA spokesman Bruce Buckingham. Workers will replace all nine fuel temperature sensors, one of five main computers that failed and another malfunctioning computer part, he said.

The first hint of trouble came Monday night when the launch team received additional data from the manufacturer of a temperature sensor in Columbia's main propulsion system that was replaced last year, NASA test director Mike Leinbach said. The welding on that sensor was cracked and had contributed to hydrogen fuel leaks that grounded the shuttle for months.

Columbia flew in December, and the replacement sensor and eight other fuel temperature sensors worked fine, NASA said.

But "further analysis since then seems to raise a question" about the sensors, Leinbach said. He couldn't immediately explain why word of more possible sensor problems came in just Monday.

More trouble followed.

Shortly after midnight, workers discovered a problem with one of 23 units that link the main computers with shuttle components. The malfunctioning unit, called a multiplexer-demultiplexer, converts and formats commands from the main computers. It went down and came back up but did not work properly.

Later Tuesday morning, one of five main computers in the flight deck also failed mysteriously.


(Additional information)

British woman visits Mir

A 27-year-old British chemist with no flying experience became the first woman to visit the Mir space station, but Pravda likened her to Syrian and Afghan cosmonauts who flew gratis.

President Mikhail Gorbachev hailed the coolness of Helen Sharman and the two Soviet cosmonauts who accompanied her in a direct conversation Monday with the Mir crew moments after the TM-12 capsule docked with the space station.

The official Tass news agency said the Soyuz craft apparently docked without major problems on its first attempt, as compared with past difficulties the Soviets have experienced in joining module additions to the Mir.