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Physiological mass measurements on Skylab 1/2 and 1/3
1Johnson Space Center, NASA, Houston, Texas, USA.
Acta Astronautica
|January 1, 1975
Summary
Astronauts experienced metabolic deficits and fluid shifts during spaceflight, leading to weight loss. New, simpler devices now enable mass measurements for various spacecraft objects.
Area of Science:
- Space physiology
- Biomedical engineering
- Astronaut health
Background:
- Previous space missions lacked precise methods for measuring crew and object mass.
- Understanding mass changes is crucial for astronaut health and mission success.
Purpose of the Study:
- To detail novel devices and techniques for in-space mass measurements.
- To analyze mass changes in astronauts and objects during the Skylab missions.
Main Methods:
- Development and deployment of specialized mass measurement devices.
- Conducting ground-based simulations and in-flight tests during Skylab II and III.
Main Results:
- Identified patterns of metabolic deficits and fluid redistribution causing weight loss.
- Observed rapid initial weight loss followed by post-flight recovery.
- Documented transient changes attributed to stress.
Conclusions:
- Fluid shifts and metabolic losses are primary drivers of astronaut weight change.
- Transient stress also contributes to short-term mass fluctuations.
- Development of smaller, cost-effective devices facilitates broader in-space mass measurement applications.
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