(WAFF) - An astronomical phenomenon will glide across the skies Tuesday evening when Venus crosses in front of the Sun.
Known as the Transit of Venus, the planetary event happens only twice in a century. The last Transit of Venus was in 2004, the next will be in 2117.
The Transit of Venus takes place when Venus passes directly between Earth and the Sun, appearing as a small dot gliding slowly across the face of the Sun. The 2012 transit is a seven-hour journey, but is only visible for a certain period of time depending on your geographic location.
Historically, the rare alignment is how astronomers measured the size of our solar system. Venus transits occur in pairs that are eight years apart, and then separated by long gaps of more than 100 years.
It's important to note that looking directly into the Sun without proper eye protection can cause permanent damage.