Satellite

From Citizendium, the Citizens' Compendium

In the context of spaceflight, satellites are objects which have been placed into orbit by human endeavor. They are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon. Depending on the application, they use different types of satellite orbits.

Contents 1 History 2 Applications 2.1 Engineering test 2.2 Scientific research 2.3 Multipurpose and manned 2.4 Communications 2.5 Navigation 2.6 Weather 2.7 Intelligence 2.7.1 Imagery intelligence 2.7.2 Communications intelligence 2.7.3 Electronic intelligence 2.7.4 Measurement and signature intelligence 3 Engineering challenges 3.1 Weight 3.2 Power 3.3 Cooling 3.4 Orbital drag and station-keeping

History

The first artificial satellite was Sputnik 1, launched by the Soviet Union on 4 October 1957. This triggered the Space Race between the Soviet Union and the United States.

Applications

Engineering test

Scientific research

Multipurpose and manned

Communications

Navigation

Weather

Intelligence

Imagery intelligence

Communications intelligence

Electronic intelligence

Measurement and signature intelligence

Engineering challenges

Weight

Power

Cooling

Orbital drag and station-keeping