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pavelrub | 4 years ago

Satellites in general aren’t maneuverable. The camera angle can be changed to point at, and capture, a region of interest when the satellite passes over it, but the satellite’s orbit is determined on insertion and doesn’t change on demand.

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Symbiote|4 years ago

Satellites can be moved, for example to avoid a collision with another satellite or debris, or to semi-permanently change the orbit. They have some sort of propulsion to allow this, and also counter atmospheric drag etc.

However, the lifetime of the satellite is generally limited by the amount of propellant (or whatever), after it's run out the satellite is useless. So it's not done on a whim.

pavelrub|4 years ago

They have a very limited amount of hydrazine, used for small course corrections for drag compensation and debris avoidance. It's not used, nor can be used, to "change orbit" in the sense of redirecting the satellite to look at some specific location on demand, outside of the satellite's original orbit.

alangibson|4 years ago

Parent post is correct. Raising and lowering the orbit is a matter of burning a reasonable amount of rather limited fuel. But making a left hand turn at 17.5 km/h is incredibly energy intensive.

Look at the SpaceX launch of DART. They needed a whole rocket to lift a tiny payload due to needing to turn roughly 45 degrees

numpad0|4 years ago

You just put one in a polar orbit and tell them to look at coordinates next time it is to pass that area over. Earth rotates under it meanwhile.

temp0826|4 years ago

Exception of course being the X-37B spy "satellite"