The space shuttle Atlantis lifted off in the early morning hours May 15 on the sixth docking mission between the shuttle and Mir, bringing a new astronaut to stay on Mir as well as key equipment for the aging station.
     Atlantis lifted off on mission STS-84 as scheduled at 4:08am EDT (0808 UT) Thursday May 15. The countdown was free of any problems and the shuttle reached orbit normally.
     Atlantis will maneuver towards Mir, with docking scheduled for 10:38pm EDT (0238 UT) Friday May 16. The shuttle and Mir will remain docked for five days to transfer crew and supplies.
     While the spacecraft are docked, Atlantis astronaut Michael Foale will trade places with Jerry Linenger, who has spent the last four months on the station. Foale will remain on the station for a four-month tour of duty while Linenger returns to Earth with the remainder of the Atlantis crew.
     A Spacehab module in the shuttle's cargo bay will be used to conduct a number of experiments while on orbit, including several experiments contributed by the European Space Agency to study biological processes and material processing in microgravity.
     Atlantis will also transfer key supplies to Mir, including about 450 kg (1,000 lbs.) of water and 385 kg (845 lbs.) of science equipment. Atlantis is bringing a new oxygen generator unit to replace one of the systems on Mir that broke down in March and equipment to repair leaks in the station's cooling system.
     The Atlantis crew, commanded by Charles Precourt, is one of the most diverse in shuttle program history. The seven-person crew includes one Russian cosmonaut, Elena Kondakova, and French astronaut Jean-Francois Clervoy. Foale is American but was born in Britain, while mission specialist Carlos Noriega is American but was born in Peru.
     Pilot Eileen Collins and mission specialist Edward Lu round out the crew.
     The shuttle is scheduled to land at the Kennedy Space Center Saturday May 24, at 7:52am EDT (1152 UT).

A McDonnell Douglas Delta II launched the first five satellites in the Iridium communications system on May 5, three and a half months after another Delta II exploded seconds after launch.
     The Delta II lifted off from Vandenberg Air Force Base in California at 10:55am EDT (1455 UT) Monday May 5. There were no problems with the launch and the five satellites were successfully placed in the proper orbit.
     The launch had been scheduled for May 2, but was delayed on two successive days due to high winds. A communications problem at launch control delayed the scheduled May 4 launch. The launch had been planned for mid-January, but had been delayed due to several minor problems before the explosion of a similar rocket in Florida grounded all Delta IIs.
     The launch was the first since the January 17 explosion of a Delta II 13 seconds after launch from Cape Canaveral, Florida. An Air Force report released Friday, May 2 concluded that the explosion was caused by a cracked casing in one of the nine solid rocket boosters attached to the first stage of the rocket, which triggered the self-destruct system on the booster when the casing catastrophically failed.
     The report, however, could not explain why the casing had cracked. The report did not rule out three possible causes for the crack, including debris striking the booster after launch, mishandling of the booster during assembly or testing, or sabotage from a gun shot near the launch pad. The report did conclude, though, that sabotage was "highly unlikely."
     The launch from Vandenberg placed the first five spacecraft of the 66-satellite Iridium constellation into orbit. When complete, the system will provide global access to voice, fax, and data communications. The next Iridium launch will take place from Baikonur Cosmodrome in Kazakhstan in June.
     Iridium is scheduled to be in place by September 1998, despite the nearly four-month delay in launching the first spacecraft. Iridium managers say the schedule for launching all 66 spacecraft has enough flexibility to accommodate delays without pushing back the beginning of operations.
     The launch was originally scheduled to handle three satellites, but the payload was boosted to five when the satellite carrier and deployment system was replaced with a lighter graphic composite system after the January explosion. The savings in weight allowed the payload to be expanded.

A hybrid-fuel rocket launched from a balloon on May 11 became the first amateur-built rocket to fly into "the edge of space", reaching a peak altitude of 64 kilometers (40 miles).
     Space Launch 1 of Project HALO (High Altitude Lift-Off), a project of the Huntsville Alabama L5 (HAL5), took place on the morning of Sunday, May 11, with a balloon launch from Hampstead, North Carolina. Ninety minutes after the balloon lifted off, at an altitude of 18 km (60,000 ft.), the rocket it carried ignited and flew a suborbital trajectory above the Atlantic Ocean.
     The HALO team had planned to launch the rocket when the balloon reached of 30 km (100,000 ft.), but were forced to launch early when a seam burst in the balloon at the lower altitude. As a result, the rocket reached a peak altitude of 64 km (40 mi), less than their planned peak of 108 km (67 mi.)
     "We're very pleased with today's results and we learned a great deal," said HALO program manager Gregory Allison. "There were many challenges and many unknowns, but we worked through them all."
     HALO has been an ongoing project of HAL5 for several years, with the goal of developing a launch system that could make space access more affordable for students, amateurs, and other researchers.
     To achieve this goal, the HALO group revived the concept of the "rockoon", or balloon-launched rocket, which had been developed in the 1950s but not widely used. The group developed a hybrid-fuel rocket, combining ordinary asphalt as a solid fuel and nitrous oxide -- laughing gas -- as a liquid oxidizer.
     The launch was the first step in developing an operational launcher. "We've succeeded in proving the concept, now we're ready to proceed to operational phase," Allison said.
     "Their achievement represents a great grassroots accomplishment in the effort to lower the cost of getting into space," said National Space Society executive director David Brandt, "a major goal for everyone working in space today, from NASA to industry to private citizens."