A literal once-in-a-lifetime event occurs this Tuesday, when the silhouette of the planet Venus crosses the visible face of the Sun over several hours. Here’s when and where to see it.
What can you expect to see?
“Venus will take about 6 hours 30 minutes to cross the northern side of the Sun. The line is plotted as seen from Earth’s center. Universal Times (also geocentric) are given for the event’s four contacts: I and II as Venus moves onto the Sun (called ingress), III and IV as it leaves (egress) and for Venus’s deepest encroachment onto the solar disk.” (Credit: Leah Tiscione/Sky & Telescope)
Where will the transit be visible?
“For most of North America, the transit of Venus will begin on the afternoon of June 5th and still be in progress at sunset. Those in western Pacific, eastern Asia, and eastern Australia see the whole show from beginning to end on June 6th (local date). Click here for a larger, worldwide map.” (Credit: Michael Zeiler / Eclipse-maps.com)
How’s the weather going to be?
“Based on statistical averages of daytime clouds during June, the American Southwest, northern Australia, and the Middle East offer the best chances of clear skies for the transit of Venus. Click here for a larger version.” (Credit: Jay Anderson)
Why does it matter where on the Earth one is located?
“Your location north or south on Earth slightly affects the apparent path you see Venus taking south or north across the Sun. In 1716, Edmond Halley realized that measurements of this offset, done by timing Venus’s contacts with the Sun’s edges, could be used to determine Venus’s parallax as seen from Earth and hence the distance to both Venus and the Sun. That in turn would give the correct scale of the entire solar system, which was poorly known at the time.” (Credit: Sky & Telescope)