The best place to launch a satellite into geostationary orbit is from a launch site near the equator, to take advantage of the rotation of the Earth. But satellites are also launched from the equator into other orbits.
A geostationary orbit is about 36,000 kilometres from the surface of the Earth. In it, a satellite appears to hover over a fixed point on Earth, a location ideal for communications satellites and for some Earth observation satellites.
The easiest way to attain the right speed for orbiting a geostationary satellite is to launch it along the equator in the direction of the Earth’s rotation. The launcher then gets a boost from the Earth which, at the equator, moves at a speed of 1675 kilometres per hour. Thus the rocket can do its job with less propellant.
Space on board a launcher is limited. The load carried divides between the useful payload (satellites) and the propellant. The greater the payload capacity, the lower the cost for orbiting each satellite. First, the launcher orients itself in the satellite’s orbit, and then it releases the satellite. Thereafter, the satellite stays in its orbit, which it can adjust as needed using small on-board thrusters.
French Guyana is a good site for launching satellites into the equatorial plane. Here, ESA’s powerful Ariane 5 rockets are launched. The Ariane 5 has a load capacity of up to eight tons, enough to orbit the heaviest satellites.
Other orbits
If a satellite is to be launched into a polar orbit (orbiting pole to pole, instead of around the equator), its launch rocket gets little or no help from the Earth’s rotation. In theory, such a satellite may be launched from anywhere on Earth. But a rocket launch base is expensive, so it’s actually cheaper to have a base at the equator to meet all launch needs.
French Guyana is vital for the European space industry, and its launch area is called "the spaceport".
The easiest way to attain the right speed for orbiting a geostationary satellite is to launch it along the equator in the direction of the Earth’s rotation. The launcher then gets a boost from the Earth which, at the equator, moves at a speed of 1675 kilometres per hour. Thus the rocket can do its job with less propellant.
Space on board a launcher is limited. The load carried divides between the useful payload (satellites) and the propellant. The greater the payload capacity, the lower the cost for orbiting each satellite. First, the launcher orients itself in the satellite’s orbit, and then it releases the satellite. Thereafter, the satellite stays in its orbit, which it can adjust as needed using small on-board thrusters.
French Guyana is a good site for launching satellites into the equatorial plane. Here, ESA’s powerful Ariane 5 rockets are launched. The Ariane 5 has a load capacity of up to eight tons, enough to orbit the heaviest satellites.
Other orbits
If a satellite is to be launched into a polar orbit (orbiting pole to pole, instead of around the equator), its launch rocket gets little or no help from the Earth’s rotation. In theory, such a satellite may be launched from anywhere on Earth. But a rocket launch base is expensive, so it’s actually cheaper to have a base at the equator to meet all launch needs.
French Guyana is vital for the European space industry, and its launch area is called "the spaceport".
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