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Lagrange point
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Definition/Summary
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| One of 5 positions in an orbital configuration which includes two significantly massive bodies where objects can be placed and maintain relative position with respect to the two bodies. |
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Scientists
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| Josef Lagrange |
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Recent forum threads on Lagrange point
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Breakdown
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Physics
> Astro Cosmo
>> Celestial Mechanics
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Images
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Extended explanation
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In a situation where you have one body(m2) orbiting another(m1) (Such as the Earth orbiting the Sun), there are five points relative to these bodies where you could place a small object and have it retain its relative position with respect to the two bodies. These point are designated L1, L2, L3, L4, & L5
L1 is located on the line joining the m1 and m2.
L2 is on the opposite side of m2 from L1.
L3 is located on the opposite side of m1 from m2 and at the same distance from m1 as m2
L4 is located 60° ahead of m2 in its orbit
L5 is located 60° behind of m2 in its orbit.
L1, L2 and L3 are only metastable in that if an object placed there is disturbed in any way it will tend to drift away from the Lagrange point.
L4 and L5 are stable if m1 is at least 24.96 times more massive than m2. In this case, if an object placed at one of these Lagrange points is disturbed, it tends to drift back to the Lagrange point.
L4 and L5 are sometimes called Trojan points, due to the fact that the asteroids that have collected at the L4 and L5 points of Jupiter have all been named after heroes from the Trojan war. Also, objects found at L4 and L5 are sometimes called Trojan objects for the same reason. |
Commentary
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