A loose screw in a gearbox was the cause for the jammed hatch that canceled two spacewalks on the shuttle Columbia on its most recent mission, NASA officials announced Wednesday.
     NASA will inspect the hatch on the shuttle Atlantis for any similar problems, but has no plans to delay the January 12 launch of the shuttle on the fifth Mir docking mission.
     The screw was found during an inspection of the hatch after the shuttle landed December 7. Technicians swapped out the gearbox with a replacement, and found the hatch worked as expected.
     A later X-ray of the gearbox found a screw that had come loose within the gearbox. A second screw came loose but remained in place and did not contribute to the hatch problem.
     The stuck hatch prevented astronauts Tamara Jernigan and Thomas Jones from conducting a pair of spacewalks that would have tested tools and techniques to be used in the assembly of the International Space Station.
     The canceled spacewalks were the only major problems in the record-setting mission. The shuttle spent nearly 18 days in orbit, breaking the record for the longest shuttle mission by close to a day. The mission had been extended by two days because of poor weather at landing sites in Florida and California.
     Meanwhile, engineers are also studying damage to the nozzles in the shuttle's solid rocket boosters similar to that seen on the previous mission. Up to 30 grooves were seen in insulation of both nozzles after a post-flight inspection.
     The grooves are like those seen in the nozzle of one of the boosters after the launch of Atlantis in September. The Columbia mission was delayed one week because of an investigation into the cause of the boosters.
     At that time no verifiable cause for the damage had been located, but both a NASA and an outside panel decided that the damage did not threaten the safety of the shuttle crew, nor did they believe the damage would reoccur.
     It's not known whether investigation of the damage will have an impact on the next shuttle flight. Atlantis is scheduled to launch January 12 to dock with the Russian space station Mir. The shuttle will pick up astronaut John Blaha, currently on the station, and replace him with Jerry Linenger.

Funding problems within the Russian Space Agency are expected to delay the launch of a key Russian-built module for the International Space Station by at least 8 months, pushing back the first manned station mission to 1999.
     NASA space station program manager Randy Brinkley said December 5 that the Russian Service Module, scheduled for launch in April 1998, would not be launched until the end of 1998.
     The module would serve as the control center of the station and also provide temporary living quarters during the space station construction.
     A three-man crew, including one American and one Russian, would have blasted off in a Soyuz capsule in May 1998 to become the first crew on the new station. Such a mission would now be rescheduled for no earlier than 1999.
     "They [the station crew] would not go until the Service Module is operational," Brinkley said.
     The Russian government has not released money to continue the assembly of the module. In addition, Reuters reports that Energia, the prime contractor for the module, owes up to $100 million to subcontractors, who refuse to work on the module until they are paid.
     Brinkley said NASA is considering a number of options, including fronting Russia money from later in the station project to provide money now to complete the Service Module. Contingency plans which call for abandoning the Russian-built module for an American one are also being prepared.
     "There have been discussions at the various levels of the government up to and including the White House," Brinkley said. He also said the problem may not be resolved until February, when Vice President Al Gore meets with Russian Prime Minister Viktor Chernomyrdin.
     Brinkley is still optimistic that the Service Module will be completed with no impact on final schedule, which calls for the station assembly to be completed in 2002. "We believe we will be able... to incorporate the Service Module into the assembly sequence at a later date than originally planned... without any major perturbations," he said.

Scientists and officials with the Defense Department's Clementine project confirmed December 3 that the spacecraft discovered a field of ice in a permanently shadowed crater at the south pole of the Moon.
     As reported in December issue of SpaceViews, the finding was based on a "bistatic radar" experiment using the spacecraft's radio transmitter and receivers on Earth. The results were reported in a research article in the November 29 issue of the journal Science.
     While the paper pointed to the possibility that other ices, or sulfur, had actually been detected by Clementine, scientists at the Pentagon press conference were far more unequivocal that the discovery was water ice.
     "Ice is the most likely thing," said Dr. Stewart Nozette of Lawrence Livermore Labs.
     The ice is located in a region of a crater more than 10 kilometers deep, hidden in permanent shadow. Scientists believe that the ice is composed to tiny crystals trapped between grains of the lunar regolith, and not a single frozen lake. The ice likely came from comet impacts on the Moon.
     The discovery has raised the possibility of using the ice to support a manned base on the Moon or as rocket fuel. "So for the first time we know now there are deposits of water at the south pole of the Moon that are there, apparently accessible, and ready to use," said Paul Spudis, a scientist who worked on the discovery.
     NASA plans to launch the Lunar Prospector mission in 1997 that will provide a more detailed examination of the Moon than what the Clementine mission did in 1994. Lunar Prospector will carry instruments that will be able to confirm the ice discovery.

After two delays due to weather and technical problems, the Mars Pathfinder spacecraft lifted off from Cape Canaveral in the early morning hours of December 4 on a seven-month flight to the Red Planet.
     A Delta II carrying the one-ton Mars Pathfinder spacecraft launched at 1:58am EST (0658 UT) December 4. The launch took place without problems, and the spacecraft was placed into a Mars-bound trajectory a little over an hour after launch.
     The launch had been delayed twice in the previous two days. The first launch attempt on December 2 was scrubbed due to poor weather at Cape Canaveral. A second launch attempt was halted with just over a minute left in the countdown December 3 when a ground-control computer failed.
     The spacecraft will cruise for the next seven months on its way to Mars, arriving there July 4. The spacecraft will land on the surface using a combination of parachutes and airbags, which will inflate just before landing to cushion the shock of hitting the surface at up to 100 kmph (60 mph).
     Mars Pathfinder carries a number of experiments to study the surface and atmosphere of Mars. The spacecraft also carries Sojourner, a 10-kg (22-lbs.) rover that will spend up to a week exploring the Martian surface around the landing site.