U.S. Postal Service celebrates solar eclipse with heat-transforming stamp

A Total Solar Eclipse Forever stamp is seen in this undated image. (U.S. Postal Service)

CAPE CANAVERAL, Fla. - The U.S. Postal Service is going all out for this summer's total solar eclipse, with a first-of-its kind stamp.

Just touch the stamp with your finger, and the heat transforms the image of the blacked-out sun into the moon. Remove your finger, and the eclipse reappears. The trick is using temperature-sensitive ink.

There's a map on the back of the stamp sheet showing the eclipse's diagonal path across the U.S. on Aug. 21, as the moon covers the sun in the sky.

It will be the first total solar eclipse visible in the contiguous United States since 1979 and the first one coast to coast since 1918.

Announced Thursday, the Forever 49 cent stamp comes out in June - on the summer solstice.