Weightlessness
Videos
Weightlessness is the complete or near-complete absence of the sensation of weight, i.e., zero apparent weight. It is also termed zero g-force, or zero-g or, misleadingly, zero gravity.
Astronauts on the International Space Station experience only microgravity and thus display an example of weightlessness. Michael Foale can be seen exercising in the foreground.
NASA's KC-135A plane ascending for a zero gravity maneuver
Inside a Russian Ilyushin 76MDK of the Gagarin Cosmonaut Training Center
Zero-gravity testing at the NASA Zero Gravity Research Facility
The effects of spaceflight on the human body are complex and largely harmful over both short and long term. Significant adverse effects of long-term weightlessness include muscle atrophy and deteriora
Weightlessness
…may harm the brains of astronauts and accelerate the onset of Alzheimer's disease. In October 2015, the NASA Office of Inspector General issued a health hazards report related to human spaceflight, including a human mission to Mars. Space motion sickness (SMS) is thought to be a subtype of motion sickness that plagues…
American astronaut Marsha Ivins demonstrates the effects of microgravity on her hair in space
This 1768 painting, An Experiment on a Bird in the Air Pump by Joseph Wright of Derby, depicts an experiment performed by Robert Boyle in 1660 to test the effect of a vacuum on a living system.
Bruce McCandless II floating free in orbit with a space suit and Manned Maneuvering Unit.