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Mercury Transit Authority
The Solar System > To be sure, there are extremely important events transpiring around the globe; problems in North Korea, the Middle East, and the Persian Gulf, politics, world hunger, and so on and so on.
So, on the Importance Scale, next week's cosmic event is probably not in anyone's Top Ten. But it is one of those rare phenomena that bears considering. And it is kinda cool.
Next week, on Wednesday the 8th, Mercury will perform a celestial feat that won't be duplicated until 2016. It will cross in front of the Sun in something astronomers call a "transit." And we on the West Coast can see the whole thing! Yay for us!
As you know, Mercury is a tiny planet that hugs the Sun at less than half the distance we are. And just as the laws of planetary motion predict, our little neighbor speeds around the Sun in a fraction of the time we do - a mere 3 months. That is mercurial to say the least.
Now if it moves that quickly, and if it is between the sun and us, this "transit" thing should happen all the time, correct? Not necessarily. Poor Mercury's orbit isn't exactly lined up with ours. Its "orbital plane" has been knocked out of alignment with most of the rest of the planets, so it is most often above or below the Sun as it passes between.
But next Wednesday, from about 11 AM to about 4 in the afternoon, it is lined up just right for us to see its dismal, pathetic attempt to eclipse the enormous Sun.
Only those of us living on the West Coast - or someone stranded in the Pacific between the mainland and Hawaii - will be able to see the whole show.
But of course we can't go out and just start staring at the Sun in hopes of seeing a tiny, almost imperceptible dot cross in front of it. You must use some sort of instrument to help you.
One can use the traditional binocular-and-a-piece-of-cardboard trick (for details see: http://www.space.com/scienceastronomy/solarsystem/solar_eclipse_view.html). Or you can purchase solar filters for your scope, making sure, of course, that the filters are the type that are placed in front of your scope. Filters put on the eyepiece alone pretty much guarantee a small fire and the soon purchase of a white cane with a red tip.
These filters are available online or locally at Oceanside Photo and Telescope, and can be used even after the transit to see sunspots as we head towards higher solar activity in the next several years.
But, you may say, I have no binoculars, or scope, or money for filters! Well, alrighty then, there is another option. You can contact your local astronomy club and ask them to set up something. And the very same Oceanside Photo and Telescope will have telescopes set up all day Wednesday in front of the store - weather permitting - so you can see the transit for yourself.
So, bottom line, there are no excuses for missing this rare event!
In the next weeks after the transit, as a follow-up, you might try to spot Mercury in the predawn skies starring in its next role as Morning Star.
One more bit of trivia. What is the only other planet allowed to transit the Sun? Why, it's Venus of course. A planet has to be on an inside lane around the Sun to try and come between the sun and us. Only Mercury and Venus fill that requirement. But alas! Venus won't be crossing that great ball of fire until 2012. So make the most of next Wednesday's transit!
Until next time, clear skies!
Posted by Mark Ritter at 2006.10.28 01:59 PM | Comments (0)
