Readings | Presentations | Still Images | Links
Overview
Performing experiments in space is an expensive and time-consuming process. An investigator would be extremely fortunate to fly one experiment a year for several years in a row. For this reason, scientists are constantly looking for ground-based models that simulate the effects of microgravity on their experimental subjects. Although no ground-based model can perfectly simulate the effects of microgravity, models allow scientists to gather preliminary data and expand their knowledge of certain phenomena observed in space without the cost or complication of a space flight experiment.Ground-based models for studying the cardiovascular system include head-down bedrest and lower body positive pressure, which both cause a pooling of fluids in the upper body similar to that seen in microgravity. Bedrest is also used to simulate the wasting observed in the musculoskeletal system in microgravity and hind-limb suspension in rats induces the same type of disuse atrophy seen in astronauts in space. Plant biologists can make use of a clinostat, a motorized wheel that holds a plant parallel to the ground and rotates like a car wheel. As the plant rotates, both the stem and roots will grow horizontally instead of exhibiting characteristic geotropic (gravity-oriented) responses.
None of the above models are an ideal simulation of the microgravity environment, but they do provide important supplementary information to scientists. Researchers continue to search for improved models of how microgravity effects humans, animals, and plants.
Readings
Clinostats and BioreactorsPresentations
Simulators & AnalogsStill Images
Head-Down Tilt Bed Rest
Source: Ames Research Center
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Description: Head-down tilt bed rest is a way for researchers on Earth to simulate the effects of microgravity-induced fluid shift on the body. (Posted on 12/00)
Centrifuge in Motion
Source: Ames Research Center
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Description: The 24-foot Diameter Centrifuge at NASAÕs Ames Research Center enables study of hypergravity on small animals.(Posted on 5/04)
KC-135 in Flight
Source: Ames Research Center
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Description: KC-135, NASA's Reduced Gravity aircraft provides seconds of simulated microgravity.(Posted on 5/04)
Human Research Facility
Source: Ames Research Center
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Description: This image shows several research subjects undergoing head-down tilt bed rest at the Ames Research Center Human Research Facility. (Posted on 12/00)
Human Research Facility Shower
Source: Ames Research Center
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Description: This image shows the shower at the Human Research Facility and gives a picture of how subjects undergoing head-down tilt bed rest manage daily life. (Posted on 12/00)
Links
Artificial Gravity at MIT
Scientists and engineers at Massachusetts Institute of Technology's (MIT) Man Vehicle Laboratory are tackling issues related to human exposure to microgravity via experiments in artificial gravity.The Center for Gravitational Biology Research
The Center for Gravitational Biology Research (CGBR) manages a set of ground-based facilites at Ames Researh Center.