Re-entry
Salyut 1 was moved to a higher orbit in July and August 1971 to ensure that it would not be destroyed prematurely through orbital decay. In the meantime, Soyuz capsules were being substantially re-designed to allow pressure suits to be worn during launch, docking maneuvers, and reentry. However, Salyut 1 ran out of supplies before the Soyuz redesign effort was concluded, and it was decided to fire the engines for the last time on October 11, to lower its orbit and ensure prompt destructive re-entry over the Pacific Ocean. After 175 days in space, the first real space station came to an end.
Pravda (October 26, 1971) reported that 75 percent of Salyut 1's studies were carried out by optical means and 20 percent by radio-technical means, while the remainder involved magneto-metrical, gravitational, or other measurements. Synoptic readings were taken in both the visible and invisible parts of the electromagnetic spectrum.
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