" The Lagrange Points"
The 5 Lagrange points were discovered by an Italian-French mathematician, Josef Langrange.
Simplified Definition: These are specific locations where the gravitational pull of 2 big masses would not influence a third smaller mass into their Orbit. Another words, these 5 points are free of gravity until being sucked into the orbit of one of the two bigger masses. Remember it deals with Orbits. Of the 5 Langrange points, 3 are unstable, which means, depending on the day, the smaller mass will enter one of the larger masses Orbit. The other 2 are stable, which means that you will stay in that location forever and will always be located at the same distance of the two larger masses. Just think, if you lived in a planet on Langrange 3, you would never see the Earth (Look At Figure). Bare with me, Please..
Lagrange 1 (L1): This location has an uninterrupted view of the sun. It is also home to the SOHO Satellite (Solar and Heliospheric Observatory Satellite).
Lagrange 2 (L2): This location of the Earth-Sun System will soon be home for the MAP Satellite, the next generation Space Telescope.
Note: Since L1 and L2 are unstable for time scale of approximately 23 Days, then satellites parked there must make course and attitude adjustments regularly.
Lagrange 3 (L3): Since it remains behind the Sun all the times, NASA has no plans here.
Lagrange 4 (L4) and Lagrange 4 (L4): L4 and L5 are stable Orbits, as long as the mass ratio of the two large masses exceeds 24.96. the Earth-Moon and the Earth-Sun systems are satisfied and also other pairs of bodies in the Solar System.
Note: There are also Lagrange Points for other Solar Systems, for example, Jupiter-Sun, Mars-Sun, Saturn-Sun... ect. The Lagrange Points discussed on this page are for the Earth-Sun System.
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