Eclipse of the moon covering the sun
Deeper Dive Series

Let’s Learn About Annular Solar Eclipses!

By Liz Klimek, Planetarium Manager

 

 

Quick Reference

What: annular eclipse (Please note: annular eclipses are different from total solar eclipses, such as the one seen from Columbia, SC in 2017. See below for more information.)

When: June 10th. Eclipse will begin around 4:12 a.m. and finish at 9:11 a.m.

Where: The “path of annularity” will stretch from Ontario, Canada, over the Hudson Bay to the western coasts of Greenland to the North Pole and on into Russia.

Those outside the path will see varying degrees of a partial eclipse. Here in Columbia, only about 8% of the Sun’s disk will be covered by the Moon at sunrise. Please remember to NEVER look directly at the Sun without proper eye protection!

How to view: although the full eclipse will not be visible here in Columbia, you can check out a livestream via timeanddate.com here.

 


 

Let’s Learn About Annular Solar Eclipses!

You may have heard that a spectacular sunrise solar eclipse is just around the corner, on June 10th. How exciting an event this is depends on where you live. For example, those of us here in Columbia, SC were treated to an amazing total solar eclipse in August of 2017. That’s because we were lucky enough to be directly in the path of totality, or the path that the shadow of the Moon took as it raced across the face of the Earth. But those in the U.S. that were not in that path saw a partial solar eclipse, which is still pretty cool but pales in comparison to the ethereal, jaw-dropping experience that a total solar eclipse brings. And for those on the other side of the world, well, they didn’t get to see any of the eclipse at all.

 

 


Fast forward to June 10th, 2021. Those in the path of the Moon’s shadow will get to see the Moon block out all but the outermost portion of the Sun’s disk in what’s called an annular eclipse. It’s what happens when the new moon moves directly in front of the Sun but isn’t quite big enough in the sky in order to completely block the Sun out. This happens because the orbit of the Moon is slightly elliptical (imagine a circle that’s slightly squished so that it’s more of an oval). As the Moon orbits the Earth, sometimes it’s a tad bit closer to us, making it appear to be a tad bit bigger in the sky, and sometimes it’s a tad bit farther from us, making it appear a tad bit smaller in the sky. This means that when the Moon passes in between the Earth and the Sun, it won’t always be big enough to completely cover the Sun’s disk. The part of the Sun not covered forms a ring of light around the dark disk of the Moon, which has been dubbed the “ring of fire.” It’s an impressive sight! But then again, it’s something you can see only if you’re in the shadow’s path.

The Moon’s shadow will sweep across a path called the “path of annularity”. It stretches from Ontario, Canada, over a good chunk of the Hudson Bay, up to the western coasts of Greenland, over the North Pole and on into Russia. Anyone who happens to live in, or is able to travel to, these remote northern places will have the ability to see the annular eclipse. You can view a NASA simulation of the Moon’s shadow moving across this path at https://svs.gsfc.nasa.gov/4910.

 

 

Eclipse of the moon covering the sun


As with a total solar eclipse, those outside of the path will see varying degrees of a partial solar eclipse, which will look like something took a bite out of the side of the Sun. This applies to those in parts of the eastern United States, anyone traversing the Atlantic, and those across the northern parts of Europe and Asia. As you go further and further away from the path, the bite gets smaller and smaller. Here in Columbia, only about 8% of the Sun’s disk will be covered by the Moon at sunrise, such that it will look like something took a tiny nibble out of the Sun. Good luck seeing even that, as the Sun will be just on the northeastern horizon, which is most likely to be hidden behind trees, buildings, and hills. Clouds are also always a possibility. By the time the Sun rises high enough in the sky to clear all of those obstructions, the eclipse will be over.

But don’t fret! You can watch a livestream of the event online at timeanddate.com, so you have an opportunity to virtually see the show. The Moon will start passing in front of the Sun at 4:12am EDT, be directly in front of the Sun at 6:41am EDT (maximum eclipse) and be completely out of the way by 9:11am.

 

 

Solar viewing with proper protective eye wear

Solar viewing with proper protective eye wear.

 

If you do attempt to view the eclipse, regardless of where you are or how much of the Sun is blocked, remember to NEVER, ever look at the Sun without proper eye protection. Special solar filters and eclipse glasses are specifically designed to protect your eyes from the damaging rays of the Sun. If you still have your eclipse glasses from 2017, take plenty of time to thoroughly inspect them for any signs of damage. If you find any, or if in doubt, toss the glasses out or tuck them away in your scrapbook as a memento and obtain a new pair.

Don’t be bummed if you completely miss this one, however. Solar eclipses are a fairly common phenomenon, occurring roughly 2-4 times a year. What’s rare is for an eclipse to occur at or near your location. Here in the U.S., we’ll be treated to an annular solar eclipse on Oct 14, 2023 and a total solar eclipse on April 8, 2024. Mark your calendars now! Even if you have to do a bit of traveling to get into the path of the Moon’s shadow, being over the continental U.S. makes the path easier to access than one that transverses the remote wilderness of a place like the North Pole.