Tuesday night Bingo will have to wait: Barring the discovery of some fountain of youth, today is the last chance you'll get to watch the second planet cross the sun in a simple, twice-a-century phenomenon called the transit of Venus. All the usual rules apply, notes the Wall Street Journal, like don't look right at it. Rather, use solar glasses, No. 14 welding glass, or project it onto the ground with binoculars. Or just watch NASA's live webcast, notes the LA Times.
But do check it out, because Venus won't be back this way until 2117. Past transits helped astronomers figure out our distance from the sun, and were vital "in understanding our place in space," one NASA official says. "So many people are missing the fact that it's a 21st-century topic," adds an astronomy professor. "It gives us a last chance in over 100 years to test ideas about distant planets." For a list of local times the spectacle will be visible, click here. (Read more Venus stories.)