Archive for June, 2012
The Transit of Venus – Coming Soon to a Horizon near You
Saturday, June 2nd, 2012Did you see the last transit of Venus in 2004? It was quite something – if you’re into those things. I am referring to the alignment of earth, Venus and the sun (no, it does not usher in the age of Aquarius and don’t break into song.) If you missed it you have another opportunity to see earth’s closest planet pass between us and the sun once again. But if you miss this one, you will not see another unless you can find a way to live for another 105 ½ years.
What is so fun about this alignment is that we can see Venus as a small black dot seemingly moving across the surface of the setting sun. Those of us in North America can set our calendars to the evening of June 5th to see this spectacle. Eastern Africa and Europe will witness it at sunrise on June 6th. So here’s some things to remember in order to appreciate the show.
Protect your Eyes
Looking into the sun is damaging to your eyes. Even though the sun is setting during the transit and a thick blanket of earth’s atmosphere is filtering its rays for you, you should still take precautions to see the event safely. Here are some things you can use.
*A pinhole projector
Rays shining through a tiny hole projects the image of the sun on a piece of paper where viewing is safe. This can be as simple as using 2 pieces of cardboard, one white, to act as a screen, and another with a pinhole through which the sun will shine. There are more elaborate pinhole projector set-ups available at this website, www.exploratorium.edu/eclipse/how.html but still within the realm of those willing to play with cardboard boxes and tape.
*A solar filter on a refracting telescope
The use of a reflecting telescope is highly discouraged, as the suns concentrated rays can destroy the telescopes mirror holders.
*#14 or higher welder’s glass
If you happen to have one lying around the house, you can be the most strangely dressed observer at your viewing party.
*Specially made solar sunglasses
These are available commercially and look like those 3-d glasses you get at the movie theater.
*A sun funnel
This is a device you can easily make yourself to attach to the eyepiece of a telescope allowing a group of people to see the event at the same time.
*Watch the live webcast
In the event the weather doesn’t allow for outdoor viewing or if you are unwilling to go outside, you can watch from your computer or smartphone. The webcast is provided by NASA and University of Hawaii Institute for Astronomy and transmitted from Mauna Kea, Hawaii.
Where to see the Transit of Venus
Find a clear view of the western horizon during sunset on June 5th of this year.
When to see the Transit of Venus
The time it takes Venus to transit from edge to edge across the background of the sun differs slightly from various locations on earth. Viewed from Westfield, Massachusetts, Venus will begin its cross-solar trip at 6:03pm, and will leave the edge of the sun at 12:51 that night, well after we will be able to see it since the sun will be below our horizon. The event will be 6 hours and 48 minutes long. Whereas in Seattle, Washington, Venus touches the edge of the sun at 3:06 pm and departs at 9:48pm, 6 hours and 42 minutes later. This 6-minute difference, and other calculations, allows astronomers to calculate the size of our solar system. The length of this article, as well as my understanding of astrophysics, doesn’t allow me to go into detail about this, yet knowing it can be done is still fascinating.
So how will you celebrate this exciting event? Check it out somewhere, because it won’t happen again until the year 2117.
For all the information you could probably need, visit www.transitofvenus.org