Transit of Venus .org

Rare Alignment

Sun, Venus, and earth align for transit of Venus

A transit of Venus occurs when Venus passes directly between the sun and earth. This alignment is rare, coming in pairs that are eight years apart but separated by over a century.

The most recent transit of Venus was a thrilling sight in 2004. After the June 2012 transit of Venus (the last one in your lifetime), the next such alignment occurs in 2117.

Global Expeditions

Parallax angle from two locations
Observers from two locations on earth see two distinct paths (red and blue) of Venus across the sun. The slight difference in times Venus takes, moving from edge to edge, can mathematically unlock the distance from earth to the sun, and thus the size of our solar system.

Edmund Halley admonished nations to send expeditions around the globe to time future transits of Venus across the sun. For 17th & 18th century transits, intrepid explorers challenged both the risks and the frustrations to answer a leading question of mankind. Not all of them made the voyage back home.

2012 Doomsday & Solar System Alignment

Includes 2012 Survival Guide

Perhaps you have heard the suggestion that an alignment of earth and the sun is contributing to a doomsday scenario in 2012. When the page turns for the old Maya calendar and the solar system is aligned somehow, the world is supposed to end. In fact, there is a significant alignment of planets in 2012 that much of the world will be watching.

Where to Be (and When)

(Click map to enlarge.)
Much of the world can witness the 2012 transit of Venus. The date depends on what side of the International Dateline you will be observing. Observers in North America will see the transit in the evening on June 5, 2012, through sunset, so you want to have a clear western horizon.

Mystery of "Black Drop"

Just before or after the circular black dot of Venus seems to touch the edge of the sun, a peculiar "black drop effect" sometimes occurs between the contact points. A ligament of darkness smears the juncture of Venus and the sun.

Simulated black drop smear You can see a similar anomaly if you almost pinch your thumb and forefinger together. Just before you sense contact, a black feature spans your two digits.

This sight...is by far the noblest astronomy affords...
-Edmund Halley

Safely See the Transit

Rear projection screen with transiting Venus

Protect your eyes. There are several safe ways to watch Venus transit the sun.

Rear projection screen
Solar filtered telescope
#14 or greater welding glass
Disposable "eclipse shades"
Live webcast
More

See the archive of the 2004 website (http://old.transitofvenus.org) for additional diverse material, though many external links from 2004 may be inactive. Rather than waiting for perfection, we are re-launching with this new transitofvenus.org for 2012.

Latest News

2004 Transit of Venus Images

http://www.astronomy.no/summary.html
Results and reflections from one of the most active observing sites--Frognerparken in Oslo, Norway.

http://vt-2004.solarphysics.kva.se/movies/
Swedish 1-m Solar Telescope on La Palma; images and movies include black drop effect and the "elusive aureole outlining the disk of Venus. It is caused by sunlight being refracted towards us in the atmosphere of the planet."

http://www.nasa.gov/multimedia/imagegallery/image_feature_184.html
NASA link to images.

http://vestige.lmsal.com/TRACE/transits/venus_2004/
From the perspective of the TRACE spacecraft, including movies with time codes.

http://nicmosis.as.arizona.edu:8000/ECLIPSE_WEB/TRANSIT_04/TRACE/TOV_TRACE_INGRESS.html
More processed images from TRACE.

june8.htm
Over 50 images of the transit of Venus as witnessed from and celebrated at Mishawaka, Indiana, USA, under good conditions. "We had successful stargazing the night of June 7; webcasts beginning at midnight (EST); clear skies at sunrise; perhaps 20 quality telescopes and viewing devices; and a crowd of enthusiasts. As third contact approached, so too did a large bank of low clouds. However, the clouds cleared in time to capture that elusive moment." Comments and early images are at june8.htm.

http://astrosurf.com/rondi/venus2004/
Photographs and movies with homemade H-alpha coronograph of Venus straddling the sun's limb; sequence of images shows Venus moving beyond the solar limb; from André Rondi.

http://atm.zaciatok.sk/atm/atm.nsf/0/0F3E5E0223691EF4C1256EB50034B66F?OpenDocument
Tomáš Maruška and the Porter team capture the International Space Station transiting the sun from Bratislava. The handiwork of Thomas Fly and others sets up successful images of both the observers and the observed. Nice work, all.

US Naval Observatory Expeditions

In 1874 and 1882, the US Naval Observatory (USNO) sent multiple teams to time the transit of Venus with the aid of photographic equipment. Expedition photographs reproduced here are in the collection of the US Naval Observatory Library.

sawhorse 1415	whaler 01416	skiff 01419	seal 01430
camp	boy 01418	sighting 01423	5observers
man 01417	observatory 01429	tripod 01431	anchor
hutfield	brooklyn 01406	practice_obs 01401	ship 01402

Launch of the New ToV Website

Ready or not, www.transitofvenus.org is re-launching in preparation for the 2012 transit of Venus. Voltaire reminds us that perfection is the enemy of good, so rather than waiting until the new website is fully ready, we are go for throttle up.

Vandals Damage Stained Glass Windows

St. Michael's Church Vandals damaged 37 panes of glass in fourteen of the windows at St Michael's Church in Hoole, England. Though none of the stained glass windows commemorating the Transit of Venus were broken, the parish acted to protect the historic windows with poly-carbonate sheets. A fundraising effort raised in excess of the £10,000, including support from the astronomy community.

What is a transit of Venus?

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