Lighting

Lighting is vital for a colony. A colony might have a limited number of windows, so lighting would be required permanantly. Plants in greenhouses might need to be lit artificially to supplement natural light. Rovers must have headlamps for driving at night or during dust storms.

Types of lighting

Incandescent

Most lightbulbs on Earth are incandescent. Fire and stars produce light via incandescence. In an incandescent lightbulb a metal filiment (Usually tungsten, the only metal that can withstand the temperatures) is heated to around 3000C. A glass bulb is fitted around the filiment and the air evacuated or replaced by an inert gas, because the filiment would oxidize and burn.

LEDs

LEDs are energy efficient, and produce little heat compared to incadescent, flourescent, and halogen bulbs.

Uses

Illumination

The primary use of lighting is illumination of a settlement. A well-lit environment is vital for the morale and safety of the residents.

Agriculture

Most plants require more sunlight than is available on the martian surface. Dust storms can also obscure the sun for months at a time. Artificial lighting is needed to at least augment the natural light.

Health

The proper wavelengths of light are needed by humans to produce Vitamin D.

Certain lights, emulating natural sunlight, are used to treat Seasonal Affective Disorder.

Open Issues

• How much light is needed for day-to-day activity? Humans have two types of vision, color and low-light. Once the vision has adjusted to low light, the average human is able to function well in the light of the full moon, but without the ability to see in color.
• How much exposure time is needed for the skin to produce enough vitamin D?