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Lagrange points. Named after Italian
mathematician

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Joseph-Louis Lagrange.

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Lagrange points are a solution
to what's called the "three-body" problem.

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Two massive objects like the Earth
and the Sun create points in space

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where their gravitational forces balance
with the centripetal force

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of the motion of a smaller third object -
like a spacecraft.

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There are five different points where
these forces balance named L1 through L5,

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L4 and L5 are known as stable points,
and they attract objects,

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like space debris, which can easily
stay in orbit around these points.

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L1, L2,
and L3 are known as semi-stable.

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To stay put here, an object,
like a spacecraft,

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would have to use some fuel
so it doesn't drift off.

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We use L1 and L2 between the Earth and the Sun

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to host satellites and telescopes without
needing an excessive amount of fuel.

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For example,
the James Webb Telescope orbits

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in L2 on the opposite side of the Earth
from the Sun.

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Lagrange points are a helpful resource
in furthering space exploration.