POSTAGE STAMP OF THE WEEK: CELEBRATING THE ECLIPSE
by Hazed
There’s going to be a total eclipse of the sun in August which will be visible to much of the US. To commemorate, the United States Postal Service has just released a new stamp.
This stamp is rather special. It’s going to be printed using thermochromic ink, which means it responds to changes in temperature. If you press your finger onto the stamp, the image of a solar eclipse turns into an image of the moon. Then as the stamp cools down it reverts back to the eclipse picture.
Sounds like a real collector’s item!