Rare Celestial Venus Event 6pm Tuesday June 5, 2012

credit: Karl Tate, space.com contributor

It's a sight none of us will ever see again. Starting at 6pm tonight until after sunset, Venus will make a stately passage across the face of the sun.

Called the transit of Venus, it's a rare celestial ballet that won't occur again until 2117. Venus will appear as a small moving beauty mark on the sun, too tiny to block the sun's light. Extremely hot Venus is one of Earth's two neighbors and is so close in size to our planet that scientists at times call them near-twins.

The transit is happening during a 6-hour, 40-minute span starting just after 6 pm EDT in the United States. Clouds in an area of disturbed weather in the Gulf of Mexico off the coast of Southwest Florida may make it difficult to view the event in Sarasota, Manatee and Charlotte counties, according to weather reports. Read Herald Tribune article on Venus Transit

To observe the transit of Venus directly you must protect your eyes at all times with proper solar filters.  However, do not let the requisite warnings scare you away from witnessing this rare spectacle.  You can experience the transit of Venus safely, provided you use proper eye protection. Don't stare directly at the sun without eclipse glasses, a properly filtered telescope or a strong welding visor. Using sunglasses won't work. Permanent eye damage could result. More on safety issues

One very simple viewer you can make is called a pinhole projector. Prick a tiny hole (several are better) in a piece of thick paper or cardboard, and let the sunlight passing through it fall on a second sheet. You'll find that the pinhole acts as a tiny lens, projecting a just-big-enough image of the sun to show the tiny dot of Venus.

Or safer yet, view the official live webcast from the top of Mauna Kea, Hawaii starting at 5:45pm.

View the Official Live Webcast from Hawaii

This will be the seventh transit visible since German astronomer Johannes Kepler first predicted the phenomenon in the 17th century. Because of the shape and speed of Venus' orbit around the sun and its relationship to Earth's annual trip, transits occur in pairs separated by more than a century.