SPACE ENVIRONMENT: ATMOSPHERE


Atmosphere affects satellites residing at the Low-Earth Orbit in the following ways:

Drag

Drag is a force that causes a satellite to fall back to Earth faster, shortening its lifetime. At less than 600 km from the Earth's surface, drag varies depending on how the atmosphere expands or contracts due to variations in solar activity.

The impact of drag on the satellite also depends on the satellite's speed, size, shape and orientation. For instance, deployable panels can make the drag more prominent, leading to satellite's shorter lifetime.

Atomic Oxygen

Radiation and charged particles can cause O2 molecules to split apart in space, creating atomic oxygen, O. In this form, metal oxidation leading to corrosion or rusting becomes more intense. This can cause degradation of exposed areas and create issues with interconnects on solar arrays and on optical surfaces.

Space Environment

References:
Understanding Space: An Introduction to Astronautics, 2nd edition, Jerry Jon Sellers, McGraw Hill, USA 2004
Spacecraft Systems Engineering, 3rd edition
 

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