Venus' transit of sun

This year's grand celebration was on June 5, 2012, the Transit of Venus! We teamed up with NASA Edge to bring you an exciting web cast from atop the summit of Mauna Kea, Hawaii.

The Transit of Venus is among the rarest astronomical phenomena and won't happen again until the year 2117. So prepare now, and don't miss out on this extremely special event!

The tiny planet Venus will show up as a little black dot against the raging furnace of the Sun, which is some 100 times larger and brighter, but because Venus is so much nearer to us — about 25 million miles from Earth, as opposed to the Sun’s 93 million miles — it will appear larger. Like a pimple on the Sun’s face.  

WHEN TO SEE THE TRANSIT IN AMERICA

The Astronomers without Borders group has created an interactive time-checker to help you find out when best to view the transit, which is available here.

In the U.S., the afternoon of Tuesday is your time to see the cosmic event, from 2pm on the East Coast, and from 3pm on the West.

It will be visible until dusk in many places.

The chart above shows the times of the 2012 transit of Venus in Universal Time (essentially the same as UTC). To know when any astronomical event occurs in your part of the world, you need to translate the times to your time zone.  

Be careful and watch for the time of sunset or sunrise in your location. In the continental United States, for example, the greatest transit took place just before sunset for most of us. During last month’s solar eclipse, which was also at sunset for U.S. locations, many people told us they missed out because their viewing location was hindered by trees or tall buildings. Don’t let that happen to you! If you’re in the continental U.S., be sure to find a viewing location with a clear view of the horizon.