Little black spot on the sun

Image from Wikipedia

"There's a little black spot on the sun today
It's the same old thing as yesterday
There's a black hat caught in a high tree top
There's a flag-pole rag and the wind won't stop"
                             - "King of Pain", Sting

Today, June 5, 2012 the orbit of the planet Venus passes between the Earth and the Sun. To those on earth who can view it, Venus appears like a small black dot crossing the orb of the sun.

This astronomical phenomenon is called the Transit of Venus, and it was first observed in 1639 by the English astronomer Jeremiah Horrocks. Horrocks and other astronomers who followed were able to use their observations to calculate the distance between the Sun and the Earth.

Here on the West Coast, you can view the Transit between 3:05 and 6:25 pm - be sure you use a safe method - do not look directly at the sun. A pinhole camera or welders' glass or one of these techniques here.

 The Transit of Venus occurs in a pattern that repeats every 243 years.Occuring in June or December, a transit is followed by a second transit in eight years. 105.5 years later, the next transit occurs. Then eight years pass, another transit, then 121.5 years.

The last Transit of Venus took place in 2004. It won't happen again until 2117.

Image from NASA

UPDATE: I was at work during the Transit, and I tried to see it through a welder's mask. I saw the sun just fine, but couldn't distinguish Venus, as the sun was about the size of a dime through the dark glass. [The Man I Love] was luckier - where he works, someone had rigged up a telescope to gather the image and project it on a wall.

How'd it look where you are?