| On August 21st 2017, a rare event occurred. Throughout America, you could observe a solar eclipse take place, and the path of totality crossed the country. This allowed millions of people the chance of a truly spectacular experience, as they saw the Moon gradually block out the Sun, until the Moon was directly in front of the Sun, resulting in a total solar eclipse. If you missed the total solar eclipse, you wouldn't want to wait for it in the same spot, as the time between total solar eclipses in the same area, is around 375 years. With the event being so rare, it is no wonder that the event has been hyped as much as it has. In celebration of the Solar eclipse, the United States Postal Service issued a Total Eclipse of the Sun Forever stamp on June 20th this year. 
The stamp shows the Total Eclipse of the Sun, where the sun is completely blocked out by the moon, so the only thing visible is the light crowning around the Moon. The stamp is made using thermochromic ink, which is heat-sensitive. If you heat up the center of the stamp by rubbing a finger on it, the black ring will change color into the image of the full moon, as seen in the picture above. It should be noted that the thermochromic ink is not UV resistant, and should be kept out of direct sunlight in order to keep the color-changing abilities. The stamp is denominated as a Forever stamp, and can be found in the Stampworld Catalogue. Another issue was also made this summer in celebration of the Solar Eclipse. This one is from Alderney, and the issue containing the six stamps shown below was issued on July 19th. 
The six stamps depict the solar eclipse as seen from six different places around the world, the places being Vancouver in Canada, Miami in USA, Hamilton in Bermuda, Dakar in Senegal, Saint Anne in Alderney, and Anadyr in Russia. The stamps are themochromic as well, and change depiction when exposed to heat. They should also be kept out of direct sunlight. The set of stamps can be found in the Stampworld Catalogue. | 
