Transit of Venus Viewing Information

As reported in Planet Waves many times, the transit of Venus across the face of the Sun June 5 (or June 6, depending on location) is one of the rarest of predictable astronomical events. It’s happening the day after a lunar eclipse (which is at 7:11 am EDT June 4) and begins mere hours before the Moon eclipses Pluto. We won't get another Venus Transit for over 100 years -- so if you have even the tiniest interest in watching, it should be worth making the effort.

This is one kind of viewing aid safe for looking at the Sun. You can wear a bear hat if you want, but it is not required for safety. Image: BBC Two.

As luck would have it -- and perhaps speaking to the theme of ‘exponentially increasing awareness' we've delineated for these events -- this particular transit will be at least partially visible form most of the Northern Hemisphere and some Southern Hemisphere land masses. First we'll cover the details for how to watch safely, and then where and when to watch.

This cannot be overstated: do not look directly at the Sun at any time without the appropriate eye protection for viewing solar events. Regular sunglasses will not protect your eyes from damage, which you will not feel because the eyes lack pain receptors. You can get inexpensive ‘eclipse shades' from astronomy equipment dealers, and even Amazon.com is selling them, though certain styles may be out of stock at this point.

Do not use homemade filters or welding glasses (they may let damaging ultraviolet or infrared radiation into the eye), and if you are viewing with children, supervise them carefully. Specialist astronomy stores sell filters for telescopes, and photography stores sell filters for cameras, but be aware that some online businesses may have run out of stock.

If you have a small telescope or pair of binoculars, the safest way to observe the transit is via projection (no, not the psychological kind!). If you stand with your back to the Sun and hold up your binoculars/telescope aimed at a piece of white cardboard, you should clearly see an image of a black dot (Venus) making its way across the Sun. If you do not own any such equipment, there will likely be plenty of local viewing sites. Contact your local observatory, planetarium, amateur astronomy or astrology group, even the science department of your local college. If you have to work during the transit, consider taking some time off. You won't get another chance to see this spectacle.

Most of the United States will be able to see a few hours of the beginning of the transit in the hours before sunset, with longer visibility the further west you are. On the East Coast, Venus will make ‘first contact' -- the moment when Venus first touches the edge of the Sun -- at 6:04 pm local time. ‘Second contact' -- the moment when Venus is full on the face of the Sun, just touching its inner edge, is at 6:21 pm. After that, assuming clear skies and a view of the western horizon, you should be able to watch Venus move across the Sun's upper edge until it sets.

Other local times for first contact across the U.S., Canada and Mexico will be earlier as you travel west (for example: Chicago at 5:04 pm; Mexico City at 5:06 pm; Salt Lake City at 4:06 pm; Los Angeles and Vancouver at 3:06 pm). Anchorage and Honolulu will see first contact a little after 2:00 pm local time -- viewers in Alaska and Hawaii will get to see the entire transit.

In northern parts of South America, the transit will still be in progress at sunset (unfortunately, the rest of that continent will not get a view).

The best places to view the entire transit in other parts of the world will be from Japan, Korea, the eastern parts of China and the Russian Federation, Australia, New Zealand and New Guinea. People on the west coast of Australia will miss the start of the transit, which will already be in progress at sunrise. Since the Sun is low in the sky in the Southern Hemisphere now, it may be necessary to find separate locations for a good view of ingress and egress -- but with six hours between those moments, you should have plenty of time to do so. On some places of the east coast of New Zealand, the Sun will set just before egress. Sample local times for when first contact will be visible in Asia are: 6:12 am in Hong Kong; 7:10 am in Seoul; 7:11 am in Tokyo (Singapore will miss first contact, but will see second contact at 12:31 pm). In Oceania, Auckland will first see the transit at 10:16 am and Sydney at 8:16 am; across the International Date Line, first visibility at Papeete in Tahiti is at 12:13pm on June 5.

For Europe (except for parts of Spain and Portugal), the Middle East, eastern parts of Africa, India and Indonesia, the transit will already be happening at sunrise, and you'll get to see the second half. This means you'll want to wake up early and be sure you find a spot with a clear view of the eastern horizon. Western Africa will not get to see the transit. In Europe, third contact (when Venus first touches the inner edge of the Sun as it begins its egress) will be visible in Helsinki at 7:37 am local time; London at 5:37 am; Moscow at 8:37 am; Rome at 6:38 am.

Information in this article is from the book Transit of Venus: 1631 to the Present by Nick Lomb, which Carol Van Strum reviewed on the Daily Astrology & Adventure blog. Our astro-photographer friend Anthony Ayiomamitis in Greece provided some viewing tips in the Resources section of the 2012 annual edition, Reality Check. You also can read additional tips on photographing solar events here.