Goals and Objectives. Goals of the ISS are to establish a permanent habitable residence and laboratory for science and research, and to maintain and support a human crew at this facility. The ISS will vastly expand our experience in living and working in space, encourage and enable commercial development of space, and provide the capability for humans to perform unique long duration space-based research in cell and developmental biology, plant biology, human physiology, fluid physics, combustion science, materials science and fundamental physics. The ISS will also provide a unique platform for making observations of the Earth's surface and atmosphere, the sun, and other astronomical objects. The experience and results obtained from using the ISS will guide the future direction of human exploration of space.
The ISS is the largest and most complex international scientific project in history. The completed station will have a mass of about 1,040,000 lbs. (470 metric tons). It will measure 356 ft (108 m) across and 290 ft (88 m) long, with almost an acre of solar panels to provide up to 110 kilowatts power to six state-of-the-art laboratories. Led by the United States, the ISS draws upon the scientific and technological resources of 16 nations: Canada, Japan, Russia, 11 nations of the European Space Agency (ESA), and Brazil.
Progress in 1999. During the year, the International Space Station (ISS) program continued to accomplish major milestones on its long journey from simple designsketches to hundreds of tons of complex hardware, successfully entering the critical stage where launches and assembly of station elements in orbit began. This second phase of the ISS program covers station assembly up to initiation of orbital research capability with a permanent crew. It will be followed, in 2001 and later, by Phase 3 which includes further expansion and completion with the addition of more laboratory and habitation facilities, structural trusses and solar power arrays. As currently planned, ISS will require a total of 45 assembly flights, with 33 to be launched by the U.S.shuttle and 12 on Russian boosters. Interspersed among these missions will be logistics missions by the shuttle (for a total of 37 shuttle flights), Russian Soyuz flights to launch crews, and multiple Progress tanker flights for refueling the growing structure in orbit.
Accomplishments during 1999 included the first crewed logistics/supply flight of a space shuttle to the early assembly in orbit in May/June (see below), testing of hardware and software for ISS elements to be launched in 2000 and 2001, successful implementation of a newly developed Multi-Element Integrated Test (MEIT) which functionally connects the first several U.S. elements of the ISS on the ground in a series of integrated tests, the completion of the Mission Control Center and the Payload Operations Integration Center, and delivery of the U.S. laboratory module "Destiny" and the airlock module to the launch site in Florida in preparation for MEIT, along with other components. Interface testing between the U.S. Mission Control Center in Houston (MCC-H) and the Russian Mission Control Center in Moscow (MCC-M, or TsUP) was also successfully completed.
ISS-2A.1: Logistics. On the second space shuttle mission to the ISS, Discovery launched on 5/27/99, the first supply flight which was regarded as a pathfinder for future heavy logistics missions to the new orbiting base. After a flawless docking on 5/29 (10:56pm), Jernigan and Barry began a spacewalk to transfer two cranes (one Russian, one US-made) from the Shuttle's cargo bay to the Station's outside, installed two new portable foot restraints, and attached three bags with tools and handrails for future assembly operations. The EVA ended on 5/30 at 6:51am, after a duration of 7h 55m. Together with STS-88, total EVA time spent on ISS construction activities now stood at 29h 17m. After the shuttle's hatch to the ISS mating adapter PMA-2 was opened on 5/29 for leak and pressurization tests, Jernigan and Tokarev opened the entrance to the Node "Unity" on 5/30 (9:14pm), followed by three more hatches through PMA-1 into FGB/Zarya (10:07pm). The other crewmembers followed and began transferring supplies, equipment and water. They also replaced 18 recharge controller units for the six Zarya batteries, installed mufflers over noisy FGB fans, and replaced a power distribution unit and transceiver of the Node communication system. At work conclusion the crew had transferred a total of 3567 lbs. (1618 kg) material to the ISS, including 686 lbs. (311 kg) water. Eighteen items weighing 197 lbs. (89.4 kg) were moved from ISS to Discovery for return, and 662 lbs. (300 kg) equipment was mounted to the ISS outside during the EVA. When the final hatch was closed on 6/3 (4:44am) and Discovery departed from ISS (6:39am) after raising its altitude with a reboost maneuver by about 6 mi. (10 km) to 246 mi. (393 km), shuttle and ISS had been linked for 5d 18h 17m, and the crew had spent a total time of 79h 30m on board ISS. Combined with the 28h 30m of STS-88, total human occupancy for the new Station now stood at 108 hours.
ICM. Work was also progressing on an Interim Control Module (ICM), built by the Naval Research Laboratory for NASA, which would provide a limited U.S. on-orbit attitude control and reboost capability as a contingency against shortfalls in the Russian contributions.
Propulsion Module. Additional contingency plans for ensuring U.S. flexibility in the future include the development of a Propulsion Module for the ISS and modifications to the shuttle fleet for enhanced reboosting of the station. The Propulsion Module is being acquired from Boeing, and preliminary designs were completed during 1999.