Apollo-Soyuz and Skylab

The public support for the Apollo moon landings quickly dwindled in the early 70's. After all, the "moon race" was more political than scientific. The American public has never had great enthusiasm for purely scientific endeavors. The entire Apollo project was meant to have had ten visits to the lunar surface, but after Apollo 17, the other missions were scrubbed.

To fill the void between Apollo 17 (Dec. '72), and the first flights of the Space Shuttle (April, '81) two projects were carried out to insure a US presence in space: the Apollo-Soyuz Test Project ("ASTP"), and Skylab.

Political events in the early 70's drove the effort of the US and USSR to conduct a joint mission. Nixon had visited China, and nuclear arms agreements (e.g., SALT-1) were negotiated-there was a lull in the Cold War. Both the Soviets and Americans needed to polish their international images.

For the Soviets, it was a chance to achieve "equal footing" with the Americans, after losing the race to the moon. For the Americans, it was a chance to close out the painful Vietnam war experience. Nixon and Soviet Premier Kosygin signed a treaty for the "Agreement Concerning Cooperation in the Exploration and Use of Outer Space for Peaceful Purposes" (5/24/72).

One aspect of this agreement was for the launch of a joint space mission, the ASTP (the entire history can be found here). In this mission a US Apollo, and Soviet Soyuz would dock in space and conduct joint experiments.

The crew for this mission would be astronauts Deke Slayton, Thomas Stafford, and Vance Brand, and cosmonauts Alexei Leonov and Valery Kubasov.

Slayton was the last of the original Mercury 7 astronauts to fly, after having been grounded for 15 years due to an irregular heartbeat. While Alexei Leonov was the first man to walk in space. Kubasov and Stafford had flown previously (Soyuz 6; Gemini's 6 and 9, and Apollo 10). Brand was a rookie.

The main new piece of hardware for the mission would be the Apollo-Soyuz Docking Module ("ASDM", here is a view from the Soyuz of the ASDM attached to the Apollo CSM). Since the US and Soviets had different ways to dock, a specific module had to be developed to allow them to rendezvous in space ( the Soyuz seen from the Apollo; Artist's conception of the docking).

This module was also necessary due to the different cabin pressures and compositions used by the two countries. The ASDM would account for this by having its own special atmosphere/life-support system. The ASDM would also house various scientific experiments.

The mission was a complete success, the only flaw was a leak of the highly toxic nitrogen tetroxide gas into the Apollo capsule that knocked-out Brand. While the astronauts fully recovered, it took nearly ten days until they were declared to be out of danger.

Skylab

Skylab was much more ambitious and scientifically rewarding than the ASTP. Skylab (history can be found here) was to be America's first attempt at a space station. The first proposal for such a mission was made back in 1962 by McDonnell Douglas. It would use the second stage of a Saturn 1b as the laboratory. This proposal was formally accepted in 1965. But shortly afterwards was cancelled due to budget reductions.

With the cancellation of the remaining Apollo lunar missions, a much-improved design resulted because a surplus Saturn V was now available to lift the space station to orbit. It could now be made much larger, and carry a wider range of scientific experiments.

Skylab consisted of four main units, the docking module, the Apollo Telescope Mount (ATM), an airlock, and the Orbital Workshop ( here is an view inside). The functions of the docking module ( pictured here) and airlock are straightforward. The ATM ( here is a picture of the ATM with its solar panels, and the makeshift heat reflector for the OW) contained an array of eight telescopes, all specialized to examine a small portion of the electromagnetic spectrum. The orbital workshop contained the living quarters and the remaining biological and material science experiments.

Skylab was successfully launched in May of '73. But right away, it was found to have suffered some problems on the way to orbit. One of the main solar power panels had broken off, while the other panel had failed to deploy. In addition, a large thermal/micrometeroid shield had been lost.

Without the thermal shield, Skylab would get too hot inside for humans to work. To make Skylab functional, a fix would have to be found for both the solar panel, and the thermal shield. Before launching the astronauts, several EVAs were practiced to do this.

The first crew (Conrad, Kerwin, and Weitz) lifted of on 5/25/73 to fix, and man Skylab. The first EVA to free the stuck solar panel failed, so the crew attempted to dock with Skylab while new ideas were examined. But they had trouble docking, and actually had to depressurize the capsule and open the hatch to manually bypass some electrical connections. Their next attempt at docking was successful.

The next day, Weitz and Kerwin entered the very hot orbital module and deployed a parasol that would shield the module from the sun. Eventually, the station cooled to a much milder 80^oF.

Meanwhile methods of freeing the stuck solar panel were investigated. The final solution was to have two astronauts conduct an EVA with cable cutters to cut loose the panel. This was successful, and Skylab was now functioning sufficiently well for the resumption of the original program ( here is what it looked like after all of the reparirs and EVAs).

Even with the difficulties, in the 28 day mission, the first Skylab crew completed 100% of their medical experiments, 80% of their solar observation program (here are some images of the sun from Skylab: UV light #1, #2 with large prominence ), and 60% of the Earth resources experiments ( here is a picture of White Sands from Skylab 4).

Skylab's second crew ("Skylab 3") completed a 59 day mission, while the third mission ("Skylab 4") lasted 84 days. The Skylab science experiments returned a wealth of data on how the human body functions in space, new information on the behavior of the sun, and insight into future uses of of the zero-g space environment to manufacture medicines and other materials.