Tuesday, June 5, 2012

Venus Transit

If you are an astronomy buff - or even if you're not - there is a very cool event happening in the sky today.

The planet Venus will transit directly between the Earth and the Sun, so will appear to travel across the disk of the Sun. It will start on June 5th at 6:04pm Eastern Time and will last for approximately 6 hours. 

The transit of Venus is a rather important astronomical event. It was actually one of the ways that the distance from the Earth to the Sun was initially calculated. At the time, astronomers new very well the relative distances of the planets, but they could not put it into km or miles. But, knowing those distance ratios and being able to accurately time how long it took Venus to transit the Sun, they were able to calculate the true distances between the planets. Transits of Mercury can also be used for this purpose.

I highly recommend trying to check this event out if you can - it's most likely the last time in your life you'll be able to see it! The next time it will happen is 2117.

Most observatories, astronomy departments, and amateur astronomy clubs will be hosting events. If you can't find any, here are some tips on how to safely observe the transit (remember: looking at the Sun is not a good idea!). If it's cloudy where you are, or you can't get outside to view it for whatever reason, NASA will be hosting live streaming video of the event.

Here in London (Ontario) - we'll be hosting an event at the Cronyn Observatory on campus, starting at 5:30pm. We'll watch the transit until the sun sets, and will then turn our telescopes to other interesting objects in the sky. If you're in town, I hope to see you there!