Thursday, October 05, 2006

Crepuscular Rays

Crepuscular rays - 6:54 a.m. - 34 minutes after sunrise
Tucson, Arizona

When I went outside this morning, I saw these crepuscular rays converging toward the rising sun. On October 1, t.beth of Firefly Forest posted a beautiful photo of crepuscular rays radiating down from the afternoon sun through a dramatic cloudy sky. This phenomenon isn't uncommon, but it's always beautiful.

I hadn't thought much about them before, but, prompted by t.beth's post, I looked up crepuscular rays on the Atmospheric Optics web site. There one can find more wonderful photos and explanations of both crepuscular rays (apparently converging toward the sun) and anti-crepuscular rays (apparently converging toward the anti-solar point, 180 degrees from the sun). In fact, the rays are parallel shafts of sunlight from holes in the clouds - the seeming convergence caused by a perspective effect. The Atmospheric Optics web site also has a spectacular photo taken with a fisheye lens of rays and shadows stretching across the earth, showing that crepuscular and anti-crepuscular rays are actually the same objects.

3 comments:

Sonia said...

Hi Pam, I only can see the first photo! Just beautiful! I am having problem with Blogger. I see on other blogs a little box with an red X in it where a picture should be. I am very upset. Did you had this problem too?

I download Firefox and let's see what's happens!

Have a nice day!

Anonymous said...

What a lovely photo - it's quite a heavenly sight isn't it?

Pam in Tucson said...

Great to have you visit, sonia.

cb - Welcome! Yes - it was quite heavenly.