Tomorrow's historical astronomical event is not just a beautiful novelty.
Tomorrow, skywatchers the world over will look up to behold a strange sight witnessed just seven times in the past five centuries. The last transit of Venus until 2117 is an occasion for astronomical celebration and historic import — we’ll be watching something the greatest astronomers of any age have traveled the world to see.
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My Comment: Mercury has provided the same data .... but Venus .... because of it's size .... will probably provide more accurate info.