Outer Space / Society
The phenomenon whereby a person's legs appear thinner in weightlessness due to bodily fluids becoming concentrated in the upper half of the body. One of the adaptation phenomena of zero gravity, causing the opposite effect of Moon face. Spaceplane crews wear special uniforms that maintain negative pressure on the lower half of the body, as the sudden rush of fluids to the upper half can cause irregular heartbeat, fatigue, and SAS. Companies offering zero gravity spa tours, which give people the chance to experience bird leg first-hand, have often been the subject of interest on Earth.