There may be tendency to give the earlier candidate premature credit. [Example: who discovered the mainland Americas? Many quote Ericson's viking settlement on Newfoundland although Newfoundland is no more the mainland than Cuba. To get to Newfoundland Ericson must have seen the Canadian coast and might have felled timber in Labrador. Columbus, on the other hand, knew he'd found mainland in 1498 (beating Vespucci by a year) due to the size of the Orinoco.]

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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.