Act 2.6 Study Guide - Space Life Support Systems

Vocabulary practice and key statistics regarding life support systems, water recycling, and oxygen generation on the International Space Station (ISS).

Daily Oxygen Requirement

$0.84\,kg$ of $O_2$ per day, which is the same for a person in space as it is on Earth.

Atmospheric Composition

The atmosphere consists primarily of Nitrogen ($78\%$) and Oxygen ($21\%$).

Daily Water Requirement (Earth)

A person on Earth requires $7\,L$ of water per day ($3\,L$ for drinking and $4\,L$ for food preparation or growing food).

Daily Water Requirement (Space)

Astronauts require $2.4\,L$ of water per day ($1.6\,L$ for drinking and $0.8\,L$ for rehydrating food or growing produce).

Space Logistics Cost

It costs $\$2,720$ to send $1\,L$ of water to space.

ISS Water Recycling Rate

Around $90\%$ of water on the ISS is recycled, with the remaining portion used for the Oxygen Generation System.

Recycled Water Sources

Water on the ISS is collected and recycled from brushing teeth, hand washing, pee, breathing, showering, and sweat.

Oxygen Generation System (OGS)

A system used to convert water ($H_2O$) into Oxygen ($O_2$) and Hydrogen ($H$).

Electrolysis

The name of the process used by the Oxygen Generation System to separate water into oxygen and hydrogen.

Sabatier System

The system used to remove carbon dioxide ($CO_2$) from the ISS cabin by adding Hydrogen to produce methane gas ($CH_4$) and water ($H_2O$).

Sabatier Chemical Reaction

$$CO_2 + 4H_2 \xrightarrow{400^\circ + \text{Pressure}} CH_4 + 2H_2O$$

Methane ($CH_4$) Disposal

After being produced by the Sabatier System, methane gas is vented out into space.

Sabatier Water Production

The water produced by the Sabatier System is processed, cleansed, and used for drinking.

Types of Space Waste

The four types of waste produced are Human waste, Wastewater, solid waste, and Gaseous waste.