2004 Venus Transit Composite This filtered composite image was captured from Donja Stubica, Croatia, during the 2004 transit of Venus. This time, the planet will cross the sun's northern hemisphere. Andjelko Gilvar/ESO
How The Last Transit of Venus in Our Lifetime Will Help Us Find Other Planets Feature -- Popular Science
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.