Context I was watching a video about the JWST and saw that it orbited the sun at the L2 point, but that got me wondering as to how it doesn’t slowly drift in its orbit, considering its at a higher (but presumably at a similar eccentricity to that of the earths) orbit. Are higher orbits not always slower?
Basically how does the JWST not fall behind the earth, for lack of better phrasing.
In: 6
It depends on the Lagrange point.
L1 (between the sun and planet) and L2 (on the side of the planet away from the sun) are only quasi stable. Think of it like balancing on the saddle of a horse. It takes occasional thruster firings to cancel out the small perturbations from things like the solar wind and the influence of the moon.
Also, the actual exact point isn’t all that useful. In the case of L1, it would actually be impossible to receive data from a probe at L1, as the radio noise from the sun would drown out the transmission from the probe. In the case of L2, the sun would be blocked by the earth, making solar power untenable.
Instead, the probes are in orbits that appear to orbit around these points. Aside from the practicalities mentioned above, this requires less fuel. This is part of the reason why SOHO has been able to stay functional for 28 years, despite being only planned for a 2 year mission.
L4, and L5 are points leading and trailing the planet, where the gravity equals out. These are inherently stable regions (think sitting at the bottom of a cup) but they’re not much use at the moment.
L3 is at the far side of the sun, and is north useless since we can’t communicate with it due to the sun being in the way, and is very unstable (think balancing on the head of a nail).
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