How many astronomers does it take to change a light bulb? 3.

One to change the bulb then moan about the light pollution it causes.
One to berate the younger generation for not being able to star hop to the socket.
One to feel nostalgic for the good ole days of the Cold War when the government would pay for the bulb.

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Yonder is Dubhe seen on Earth tonight as it was in the days of Grover Cleveland's presidency whereas this way is Deneb seen as it was in the lifetime of Muhammed . If one somehow travelled to Deneb at very close to c then whenever you looked back you'd measure Earth as closer to you than the distance you would simultaneously measure between Earth and Dubhe.