Soviet Humans Enter Space

By Marcia S. Smith, Formerly with the, Science Policy Research Division of the Library of Congress, Congressional Research Service

1981-1987

HUMANS ENTER SPACE

Yuriy Gagarin's 1961 flight was the first of six Vostok flights, the primary purpose of which was to establish the basic param­ eters of human response to spaceflight conditions. Although the series achieved that objective, skeptics remained unconvinced that the human organism would accept exposure to the space environ­ ment for more than a few days at best. Much of the concern re­volved around the experience of Gherman Titov, in Vostok-2. In his one-day flight, Titov experienced spatial disorientation and motion sickness, the first occurrence of the condition known as "space motion sickness," or SMS (referred to in the U.S. program as "space adaptation syndrome"). Table 5 lists Soviet piloted mis­ sions of interest from a biomedical standpoint, from Gagarin's flight through the end of 1983.

Although the Soviets considered SMS a serious problem, their American counterparts were skeptical. Ironically, although most Soviet cosmonauts were experiencing SMS, no American Mercury or Gemini astronaut did. Only during the Apollo era did SMS affect American astronauts, as the classic symptoms of nausea, diz­ ziness, and fullness of the head began to appear during the first hours and days of spaceflight (i.e., the "acute" phase of flight). Eventually it was recognized that the tight confines of the Mercury and Gemini capsules had prevented the head and body movements that precipitate the SMS symptoms. The roomier Soviet spacecraft allowed greater freedom of body movement.

Following the Vostok flights were two flights of the Voskhod series. Voskhod 1 flew the first three-man crew, among whom was a physician, A.D. Yegorov. This first "space doctor" obtained more sophisticated medical data during the mission, as studies of various physiological parameters were carried out although the flight lasted only one day. Voskhod 2 was notable for the first extravehi­cular activity. The eight Vostok/Voskhod missions were of short duration; the longest lasted five days. During this era, Soviet bio- medical specialists had four main objectives in view:

Provision of adequate life support (i.e., water, breathable at­ mosphere, adequate diet, and waste management) Protection of the cosmonaut against the physiological effects of the space environment, and maintenance of normal vital functions

Assurance of cosmonaut safety in the event of space module malfunction

Provision of appropriate measures post-flight to ensure opti­ mum re-adaptation to gravity.

The task appeared relatively simple. The only problem noted thus far by Soviet life scientists was SMS. However, the U.S. Mer­ cury and Gemini programs that paralleled and immediately fol­ lowed these flights gave evidence of potentially more serious physi­ ological changes. These included a 5-20 percent loss of red blood cell mass and plasma volume (4-9 percent), post flight orthostatic intolerance (i.e., an inability to stand erect), loss of weight and of exercise capacity, inflight loss of bone calcium and muscle nitro­ gen, along with decreased bone density post flight. These American findings from longer-duration missions helped to shape the biomedical program that the Soviets pursued in their follow-on Soyuz program.

References:

1. SOVIET SPACE PROGRAMS: 1981-87, PILOTED SPACE ACTIVITIES, LAUNCH VEHICLES, LAUNCH SITES, AND TRACKING SUPPORT PREPARED AT THE REQUEST OF Hon. ERNEST F. HOLLINGS, Chairman, COMMITTEE ON COMMERCE, SCIENCE, AND TRANSPORTATION, UNITED STATES SENATE; Part 1, MAY 1988, printed for the use of the Committee on Commerce, Science, and Transportation, U.S. GOVERNMENT PRINTING OFFICE, WASHINGTON, D.C. 1988