The Transit of Venus

June 5th @ 8:35am – A little off topic… but this afternoon, an event will occur that is a rare astronomical phenomenon: The transit of Venus. Over the space of nearly 6 hours, from our vantage point on Earth, Venus will pass in front of the Sun and will appear as a tiny black sphere against the blinding light of our local star. It will be visible in its entirety around the Pacific Rim, and partially over most of North America and Europe. The transit begins at 10:11pm UTC (Greenwich) where we are, which translates to 3:11pm here in the Pacific Time zone.

These transits come in pairs (due to the orbital dynamics of Earth and Venus) and this is the second of the pair for this century. Since we’re out at sea exploring the oceans, it is worth noting that Captain James Cook observed the transit of Venus in November of 1763 on one of his round the world voyages of discovery, an event he noted with a sketch in his personal log.

It’s a mostly sunny day out here, and with a boatload of scientists and engineers, we’re going to try to rig up something to see if we can safely observe it.

WARNING: NEVER LOOK AT THE SUN DIRCTLY TO SEE ANY ASTRONOMICAL EVENT! 

To observe this event, you’ll need to use #14 welder’s glass (and there is debate over whether you can use two #7s or other combinations, but play it safe and DO NOT stack different welder’s glass together), or use a pinhole in cardboard to project the Sun’s image onto a piece of paper (in other words: look away from the Sun at the paper, NOT towards the Sun). There are many sites on the Web with information on other ways to safely view the transit, or you can consult your local chapter of the Royal Astronomical Society. For details, including safe viewing tips, you can go to the Transit of Venus page of NASA’s Eclipse website.

Why the interest? The next time this will happen is on December 11th, 2117 and again on December 8th in the year 2125… make sure to tell your great grandchildren!

Blog post and photos by Scott Doehler 
Marine Educator