Spaced Out Physiology
Written by: Amy Shira Teitel
Illustrated by: Sabine Deviche

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Astronaut: a man or woman whose job it is to fly in space. Astronauts are usually really good at math and science, and aren't scared of sitting on top of rockets.

Gravity: the attraction of one body to another. Gravity gives objects weight and causes them to fall to the ground if dropped... more

Life in Space

An astronaut meal

Freeze-dried ice cream.

Astronauts seem to live the good life—floating and flipping through the air, looking at the Earth from 200 miles away, and eating special vacuum-packed meals. True, the ice cream is freeze-dried, but think of the amazing view they have while eating dessert. Being an astronaut is a cool job, but before you sign up you should know life in space isn’t all fun and games. The lack of gravity can make our bodies act in strange ways.

Living on Earth

earth and moon

Earth, seen from the moon.

All living things on Earth have adjusted to the environment. This means that over time, humans have gotten used to the conditions here. One of the things we have grown used to is gravity. Walking around under the force of gravity requires strong muscles. In low-gravity environments such as in space or in orbit around the Earth, everything changes.

What If You Worked in Space?

International Space Shuttle above Earth

International Space Shuttle.

The International Space Station is a big laboratory 200 miles above the Earth that can hold six astronauts. The men and women living there stay in a low-gravity environment for months, or sometimes more than a year. After floating around for so long, they often have a hard time walking back on Earth. Some returning astronauts have to be carried out of the spacecraft because they cannot walk. This definitely doesn’t add to the list of astronaut work “benefits.” Why does this happen and what happens to a person’s body while they are in space?

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Bibliographic details:

  • Article: Spaced Out Physiology
  • Author(s): Amy Shira Teitel
  • Publisher: Arizona State University School of Life Sciences Ask A Biologist
  • Site name: ASU - Ask A Biologist
  • Date published: December 8, 2011
  • Date accessed: June 12, 2024
  • Link:

APA Style

Amy Shira Teitel. (2011, December 08). Spaced Out Physiology. ASU - Ask A Biologist. Retrieved June 12, 2024 from

American Psychological Association. For more info, see

Chicago Manual of Style

Amy Shira Teitel. "Spaced Out Physiology". ASU - Ask A Biologist. 08 December, 2011.

MLA 2017 Style

Amy Shira Teitel. "Spaced Out Physiology". ASU - Ask A Biologist. 08 Dec 2011. ASU - Ask A Biologist, Web. 12 Jun 2024.

Modern Language Association, 7th Ed. For more info, see
Shuttle discovery taking off

Takeoff of the shuttle Discovery.

Learn about astronauts and the history of humans in space at Ask An Earth and Space Scientist.

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