What is a Lagrange Point in space sciences?
Lagrange point is a position in space where the combined gravitational forces of two large bodies, such as Earth and the sun or Earth and the moon, equal the centrifugal force felt by a much smaller third body such as a satellite or a space station.
Such interaction of the forces creates a point of equilibrium where a spacecraft may be “parked” to make observation.
These points are named after Joseph-Louis Lagrange, an 18th-century mathematician.
There are 5 such points between the earth and the sun namely – L1, L2, L3, L4 and L5.
Some USA and Japan missions placed their observatories in L1 position to study the sun. Currently India is trying to put a space observatory named Aditya-1 in L5 position to study the sun.