What’s a transit of Venus? It’s not a woman on a half-shell taking a trip on the TTC.

Henry Postulart – Toronto: Perhaps it’s best explained by astronomer Jesse Rogerson in a video he prepared  for today’s event. In short, twice every 113 years, the orbits of Earth and Venus result in Venus being positioned directly between Earth and the Sun, creating a ‘little black spot’ (as seen from Earth) which takes approximately 6-1/2 hours to cross the the Sun. The transit of Venus occurs first from one side of the Sun, then again 8 years later on the other side. The pattern then repeats 105 years later. The first part of this pattern was predicted by Johannes Keppler in the late 1620′s following his discovery and detailed analysis of the motions of the planets in our solar system. He was able to determine that both Mercury and Venus would transit the sun in late 1631. He died before these events occurred, but the predicted transit of Mercury was observed by French astronomer Pierre Gassendi, who then attempted the observation of the Venus transit. Although the transit did occur as predicted, it was not visible from Europe, as shown by modern calculations of the event. Check out the NASA site for more of the history of the science of the planetary transits.

Today was the last time this century that the event will occur. The most recent occurrence was in 2004. As an amateur science geek, I had run into the news of this event about a week ago and marked my calendar to spend some time observing it from my back yard. I was pleasantly surprised this morning to discover that newz4u.net wanted me to cover the Ontario Science Centre’s Transit Of Venus Star Party.

When I arrived at the event, I was pleasantly surprised, again, to see how many Toronto folk had found the event interesting enough to make their way through rush-hour traffic, both on the road and on the TTC, to attend the event. A number of random passers-by came up to me ask why all the people in the parking lot were staring up at the sky with their funny glasses. Invariably, once I started explaining, it turned out they had already heard about the planetary transit, but were surprised there was a formal viewing event. I offered up my ‘funny glasses’ so they could take a look and every one of them took me up on the offer and gazed at the sun for a little before shaking their head in wonder that so many people were gathered to observe a little black spot on the sun.

View of sun through Eclipser eye protectors

I’m not a professional photographer, by any stretch of the imagination, but I’ve known a lot of them in my time, so I knew going in that I would need special filters to be able to safely see or photograph any sight of Venus transiting across the Sun. I was pleased to discover that with the tiny lenses on my trusty iDevices, the Eclipse eyeglasses provided by the Science Centre doubled effectively as hand-held camera filters. Unfortunately, I didn’t have sufficient optic zoom capability to actually capture the black dot of Venus that the telescopes set up at the event displayed so clearly. Still, I like the images I was able to capture.

Once I had stretched my meager equipment to the limits of my photographic ability, I started wandering through the crowd that appeared to be growing as more people showed up after their work and school days ended. People of all ages and many walks of life were taking every opportunity to peer through the telescopes and examine various forms of pinhole cameras that had been set up to view the transit.

There was a festival atmosphere to the whole event, like a carnival, but the sole attraction was the anticipation of seeing that little black dot cross that fat old sun in the sky. As significant as these transit events have been in the history of astronomy, it struck me that today it was far more significant how downright popular this event was. As one staff astronomer pointed out to the crowd that was raptly listening to his explanation of today’s event, these planetary transits have been occurring for billions of years. But this was the first time I have ever found myself in a large crowd of non-science-geeks massed together for the single purpose of viewing a planetary event that can’t be seen with the naked eye. Not because they had to be there for school credit, just because they were interested.

Perhaps it’s a small thing to get excited about, but it really lifted my spirit to see those people peering up at the sky through their little eclipse filters with wonder and excitement and fascination. And almost to a person, with huge smiles on their faces. I feel better about the world I live in for having seen that sight.