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The Deep Space Climate Observatory, launching Sunday, will keep an eye on Earth from a very special perch. Called a Lagrangian point, the spacecrafts future home is part of a constellation of stable parking spots for satellites in orbit.

At one of these points, the pull of the sun and the Earth combine in just the right way to keep a satellite from being flung out of the solar system. The new satellite, also known as DSCOVR, wont be alone at its Lagrangian point. For 30 years, space agencies have been capitalizing on the unique properties of these quirky places. (See Spacecraft to Watch Earth and Warn of Solar Storms.)

A spacecraft in one of these pockets needs very little fuel to stay at a constant location relative to the Earth, helping extend the life of the mission.

Whats more, satellites that stay in this sweet spot between the sun and Earth avoid the dramatic temperature swings and periodic magnetic disruptions that Earth-orbiting satellites encounter as they pass behind the planet.

Five Lagrangian points, named for mathematician Joseph-Louis Lagrange, occur with any circular orbit, not just the Earths path around the sun.

The Earth and moon together create five Lagrangian points, for example. And some of the stable pockets created by Jupiters orbit have captured so-called Trojan asteroids.

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The DSCOVR satellite will travel a million miles, or roughly one percent of the way to the sun, to its home at the Earth-sun Lagrangian point known as L1. From there it will have unobstructed views of the sun and Earth.

If this is such a great location for a satellite, wont it start to get crowded?

See more here:

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