The U.S Postal Service will mark the upcoming total solar eclipse expected to be seen over large parts of continental United States in August this year with a first-of-its-kind stamp.
Changing Stamp Images
The stamp, which was designed by Antonio Alcalá of Alexandria, Virginia, uses a thermochromic ink that changes images once it is touched. The image of a blocked sun during an eclipse on the Total Eclipse of the Sun forever stamp transforms into that of a moon once it is heated by a touch of the finger.
Once the stamp cools, it returns the picture of the eclipse with the lunar orb appearing as a black disk that hides the sun.
The Great American Eclipse
The upcoming eclipse has also been dubbed the "Great American Eclipse." It will be the first total solar eclipse to take place in the continental United States since 1979. During this event, the sun will be blocked by the moon for about an hour and a half.
Although the 1979 solar eclipse was visible, it has been awhile since such an event could be witnessed from one coast to the other. The August eclipse will be visible to people who live on a 70-mile stretch connecting Oregon to South Carolina.
"The eclipse this summer will sweep a narrow path across the entire country — the first time this has happened since 1918. The U.S. Postal Service anticipates this rare event with a stamp celebrating the majesty of solar eclipses," the USPS wrote on its website.
The image on the stamp uses a photograph taken during the total solar eclipse that was seen from Libya in March 2006, which was captured by astrophysicist Fred Espenak. Espenak also took the photo of the full moon that appears when the stamp image is pressed. The back of the stamp pane likewise has a map of the eclipse path and provides the times that the cosmic event will appear in some locations.
Thermochromic Ink
The U.S. Postal Service said that this is the first time that it used thermochromic ink on a stamp. The special ink is sensitive to ultraviolet light so it needs to be stored away from direct sunlight. To ensure safe storage, the Postal Service will also sell a special envelope to store these stamps.
The stamps will be sold at a special event at the Art Museum of the University of Wyoming in Laramie on June 20. It can also be preordered by visiting the link usps.com/shop. Deliveries will be made after June 20.
Opportunities With The 2017 Total Solar Eclipse
The August 21 event is anticipated to cause a boom in tourism. It also offers researchers scientific opportunities.
"The very dark color of the moon can be used to calibrate X-ray imagers to properly record the 'zero signal' state, while the eclipse will block out the disk of the sun letting the light from the mysterious inner corona within 100 km of the solar photosphere shine into various experiments for detailed study," NASA said.