Showing posts with label Sun. Show all posts
Showing posts with label Sun. Show all posts

Tuesday, October 8, 2013

Sun Dog

This photo was quickly taken while I was mowing my lawn. This is a sun dog. 
I often look for these and find them to be more common than I once thought.  Typically you'd spot a sun dog as the sun is close to the horizon, but I have seen them higher in the sky.  Notice the cirrus clouds; this is key for the creation of a sun dog.  The sunlight is refracted through the high altitude ice crystals within the cirrus clouds, and bright 'mock suns' are created 22° on either side of the sun.
Here I've circled the sun dog for easy identification..
Sun dogs are beautiful atmospheric phenomenon, and fun to spot.  Start looking out and I'm sure you'll see one soon.

Tuesday, May 22, 2012

Transit of Venus

Hey! Be sure to mark your calendar for June 5th and 6th to see the historic transit of Venus.  This will be the last one of your lifetime, as the next transit will be in December 2117.  You can check your local transit times here.

The transit of Venus occurs when Venus passes through the same orbital plane as Earth, thus enabling us to see it cross in front of the Sun (rather than above or below it).  This is the same concept as the Moon eclipsing the Sun.  This alignment occurs only every 243 years, with pairs of transits occuring 8 years apart (2004 was the last one) seperated by 121.5 and 105.5 year gaps.

Observing The Transit
First of all, never look direcly at the sun without proper eye protection.  There are a few different ways you can go about observing the sun.  The simplest and least expensive method would be some sort of projection.  I won't go into all the details, but you can make a pinhole projector or project through a lens.  You can use this technique if you have binoculars.  (Never look at the sun through binoculars unless you have approved solar filters attached to the binoculars.)  Hold the binoculars steadily pointed at the sun and a sheet of paper some distance away from the eyepiece on which to focus the sun's disc. This method is best if you have a way to secure the binoculars in position so the image is not constantly moving in and out of focus from your moving arms - trust me. It's also a great way to share the view with others.  Me personally,  I'll be projecting through binoculars.  You can read more about these methods at spaceweather.com

Enjoy the event, and clear skies to you!