Back in August 2017, there was a solar eclipse with the path of totality…where the sun is completely blocked by the moon…cutting across the U.S. from Oregon to South Carolina. Here in Arizona, about 60% of the sun was blocked out.

Solar eclipses aren’t particularly rare. There are two to five partial solar eclipses each year, with a total eclipse taking place every 18 months or so. What IS rare is when the path of a total eclipse covers a similar area just a few years apart.

On April 8, there will be another solar eclipse crossing the U.S., this time from Texas to Maine. Here in Arizona, a whopping 75 percent of the sun will be blocked by the moon.

The eclipse will start around 10:08 a.m., and reach its peak at approximately 11:20 a.m. Although it won’t be a total eclipse for Arizonans, it will still be an exciting event and if you miss this one, you won’t have another chance to see an eclipse with this much of the sun blocked out until 2045.

So, what is a solar eclipse? Before science was able to predict and explain solar eclipses, they were viewed as frightening omens. The Chinese thought that the sun’s disappearance was caused by a dragon eating the sun and would bang on drums to scare the dragon away. The Native American Pomo tribe of California thought an eclipse was from a bear taking a bite out of the sun. The ancient Greeks thought eclipses were caused by angry gods and that their appearance was the start of a period of disasters and destruction, as did the Tewa tribe in New Mexico.

Today, we understand that a solar eclipse is caused by the moon passing between the earth and the sun, causing its shadow to sweep across our planet in the course of its orbit. The area in which the sun is completely covered is fairly small. The percent of the sun that will be blocked by the moon depends on one’s distance from the area of totality. Arizonans will see only about ¼ of the sun visible during the upcoming eclipse.

The science behind a total eclipse is based on two happy and coincidental facts: the sun is approximately 400 times further away from us than the moon is, and the moon is approximately 400 times smaller than the sun. Because of that cosmic congruence, the moon and the sun appear to be the same size in the sky. The reason that makes us so lucky is that, during a total solar eclipse, the moon exactly covers the face of the sun, allowing spectators a rare chance to see the sun’s atmosphere, or corona.

The most important thing to remember about the eclipse is that it must be viewed safely. Looking at the sun can cause permanent damage to the eyes, even though the sun will be partially covered by the moon. There are various ways to safely view the eclipse, including an easily constructed pinhole camera, which can be made from a shoebox. Plus, local libraries may once again be distributing free eclipse-viewing glasses, so call your favorite branch and see if they have anything available for those interested in viewing the eclipse.

Try not to miss this cosmological event. There will be other solar eclipses for Arizona residents in the years ahead, but we won’t have this good a view of one until August 12, 2045. That’s a long time to wait for a chance to see a dragon or a bear eating a piece of the sun.