Why are total solar eclipses so rare, and how can you watch one safely?
This year, the total solar eclipse will happen on August 12, 2026. This event happens when the Moon passes directly between the Sun and Earth and blocks out the Sun's light completely. Many assume that it’s an event that happens more often, mainly because the Moon takes around a month to circle Earth. But that’s not really the case. In fact, a total eclipse is such a rare event that any single spot on Earth only gets to see one about once every 375 years.
So why are total solar eclipses so rare?
This is because the Moon's orbit is tilted relative to Earth's equator, and its shadow usually misses our planet. The shadow only reaches the ground when the Moon happens to be perfectly aligned in its orbit. Also, the Moon doesn't circle Earth in a perfect loop. Its path is elliptical, and this means that the distance between the Moon and Earth is always shifting. It changes from about 220,000 miles at its closest to roughly 250,000 miles at its farthest.
Farther out, the Moon looks smaller in the sky, and it can't fully cover the Sun. This is one of the reasons we usually see an annular eclipse, a ring of sunlight rather than a full blackout. On top of that, about 70% of the planet is ocean, so a lot of eclipse paths simply cross open water. Where the path does cross land, clouds can still get in the way and block our view of the total solar eclipse entirely.
How to safely watch an eclipse with your own eyes?
If you are planning on watching a total eclipse, make sure to be careful to not to look at it directly. As per NASA, “Viewing any part of the bright Sun through a camera lens, binoculars, or a telescope without a special-purpose solar filter secured over the front of the optics will instantly cause severe eye injury”. The sun’s surface is bright enough to damage the cells in your retina within seconds.
Instead, you can view it with solar viewing glasses and telescopes fitted with proper solar filters, as they are designed to block that light down to safe levels. With these, you can watch a total solar eclipse without putting your eyes at risk.
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