But if they want to observe planets, and planets move, wouldn't the telescope need to move too, to keep the image stable while gathering more photons? I presume very few photons reach the telescope from that far away.
That means the object's orbit need to be known before beginning it's observation, and then consuming a lot of propellant to change the telescope's speed and trajectory, possibly distance to Sun too, to track another object.
At that distance from the Sun, to track objects in another solar system, it would need to move vast distances sideways possibly taking hundreds of years.
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