Table of Contents

My Body in Space – Stepping Out

Introduction

On Earth, gravity provides a constant point of reference to orient us. In space, astronauts lack this reference point. They no longer experience "up" and "down". As a result, they may experience space sickness as their brain tries to adapt to this new sensory environment.

Half of all astronauts suffer space sickness. One contributing factor may be the conflict between what they experience through their visual and auditory senses and the absence of somatic sensations such as pressure on their feet or buttocks. The potential result of poor co-ordination is the inability to orient oneself in space. Disorientation is due in part to the fact that our brain interprets any surface beneath our feet as a floor.

Since astronauts work in a weightless environment their perceptions of the walls, ceilings and floors of the spacecraft frequently change. When they perceive another crewmember "floating" upside down, astronauts may think that it is they who are upside down relative to the other person, because of our Earth-bound idea that people stand with their heads above their feet.

Visual orientation poses a greater challenge on the International Space Station because the spacecraft consists of four intersections and numerous modules, several of which join together at a 90-degree angle. A number of the modules have equipment installed on the walls, floor and ceiling. This enables maximum use of interior space but may create visual illusions as astronauts try to orient themselves.

Astronauts report that the experience gained from working in unaccustomed orientations during training in pools and virtual reality environments helps them maintain their orientation in space.

Stepping Out is a learning resource for 5th- and 6th-grade students. It develops their ability to use the languages of science and technology to communicate ideas, procedures and results. Through problem identification and planning, the student will acquire and record data, and develop communications and teamwork skills.

This learning resource also enables students to gain knowledge about how astronauts' needs are met in space, while exploring the impact of weightlessness on the neurological systems of the body through experimentation, which allows students to practice the scientific method.