When Venus passes directly between earth and the sun, we see the distant planet as a small dot gliding slowly across the face of the sun. Historically, this rare alignment is how we measured the size of our solar system. The view is like a front row seat to the transit method, by which we now find planets around distant stars.
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Observers in North America see Venus on June 5 around 6:04 p.m. EDT until sunset. The entire transit lasts over six hours. This will be the last transit of Venus to occur in your lifetime. Next chance: December 2117.
