August 21st is the date of a total eclipse of the Sun. The eclipse will be visible all across the continental United States.

As a result, the U.S. Postal Service has issued a new stamp celebrating the eclipse.

The image on the stamp transforms from an image of the eclipse to the moon when you put your finger on it and heat it up. It's called thermochromic ink.The Postal Service says it has never issued such a unique stamp, with photos from Fred Espenak of Portal, AZ, a retired NASA astrophysicist.

Espenak, along with Jim Cochrane of the U.S. Postal Service, NASA and University of Wyoming officials unveiled the stamp on the Tuesday Summer Solstice event in Laramie, Wyoming, June 20.

A pane of 16 Eclipse Forever stamps are now on sale, with a value equal to the current First-Class Mail 1-ounce price.

Of course, Philatelists will be grabbing the other U.S.P.S. eclipse stamp products, including first day cover, digital color postmark, press sheet with Die-cut and Digital Color Postmark Keepsake.

By the way, for best results of the special ink images, keep the stamp out of direct sunlight.

That figures.

More about the stamp.