The U.S. Postal Service will release a stamp showcasing the total solar eclipse Aug. 21.  Known as the "Total Solar Eclipse Forever " stamp, it will transform from the image of a black, eclipsed sun into an image of the moon under the heat of your finger.

It's the first U.S. stamp to use thermochromic ink, which changes color with heat and light.  Rubbing the eclipse image with your thumb or finger will reveal an underlying image of the moon.

On Aug. 21, a total solar eclipse will be visible from coast to coast.  It will be the first total eclipse visible only in the USA since our nation's founding in 1776.

It will also be the first total solar eclipse to sweep across the entire country in 99 years.  The stamp's official release ceremony will take place at the Art Museum of the University of Wyoming-Laramie on June 20.  USA Today has more.