Click Here for COVID-19 Travel Updates from TravelQuest

How Often Does a Solar Eclipse Happen?

Eclipse Travel Guide

“Don’t miss this once-in-a-lifetime experience!” That’s how total solar eclipse trips are often sold—it’s a unique event, so don’t miss out. But look at our blog that lists upcoming total eclipses. There, you’ll see that as long as you’re willing to travel, total solar eclipses aren’t unique. In fact, totality occurs about every 18 months or so. But if you’re not willing to travel, then you’re going to have a bit of a wait. On average, any particular spot on Earth sees a total solar eclipse only once every 375 years!

 

When it comes to eclipses of the Sun, there are more possibilities than totality (though a total solar eclipse is, by far, the most spectacular). There are also annular eclipses, partial eclipses, and even rare, oddball hybrid eclipses. So, how often do we have a solar eclipse?

When Does a Solar Eclipse Occur?

Simply put, a solar eclipse happens when the Moon covers at least a tiny bit of the Sun’s surface. For this to occur the Sun, Moon, and Earth must be aligned, which means an eclipse can take place only during a new Moon phase. Given that there are partial, annular, and total eclipses of the Sun, the type of eclipse we see depends on how good the alignment is and whether the Sun and Moon are the same apparent size in the sky. Although the Sun is 400 times farther from Earth than the Moon, the Sun is also 400 times larger. So on average, both appear to be about the same size in the sky. But slight variations in the Moon’s orbit around Earth, and in Earth’s orbit around the Sun, mean that the apparent size of the Sun and Moon are not always equal.

If the Sun-Moon-Earth alignment is perfect, and the apparent size of the Moon is slightly larger than the Sun’s, then a total eclipse (totality) occurs. If the alignment is perfect, but the Moon’s apparent size is slightly smaller than the Sun’s, then at mid-eclipse a ring of sunlight surrounds the Moon as an annular eclipse (annularity) takes place. A rare hybrid eclipse happens when the eclipse type changes from annular to total (or vice versa) along the eclipse path. If the alignment is not perfect, we see a partial eclipse as the Moon covers only part of the solar surface, even at maximum eclipse. Note that if you’re in the path of totality or annularity, you’ll see partial eclipses before and after the ‘main event.’

Images are of totality (upper left), annularity (upper right), and partial solar eclipses (Photos of totality and the partial phases by Rick Fienberg/TQ. Photo of annularity by Jay Anderson/TQ).
Images are of totality (upper left), annularity (upper right), and partial solar eclipses (Photos of totality and the partial phases by Rick Fienberg/TQ. Photo of annularity by Jay Anderson/TQ).
Except for totality, you must always use a safe solar filter when looking at the Sun, whether it’s partially eclipsed or not (Photo by Paul Deans/TQ).
Except for totality, you must always use a safe solar filter when looking at the Sun, whether it’s partially eclipsed or not (Photo by Paul Deans/TQ).

How Often is There a Solar Eclipse?

Solar eclipses of any type happen two to five times a year. They occur in any combination of partials, annulars, totals, or hybrids, with one exception—there can never be two totalities back to back. There are always at least two solar eclipses per year, with the most common pairing being an annular and a total eclipse. If there are three or four solar eclipses in a year, the most common combination by far is three or four partial eclipses in that year. Five solar eclipses in one calendar year is very rare—it last happened in 1935 and won’t occur again until 2206. Both times, the five eclipses consist of one annular and four partials.

But how often does a total solar eclipse happen? Totalities make up nearly 27 percent of all solar eclipses, so over time, they’re not particularly rare. This averages out to approximately one every 18 months, or two totalities every three years. But that is an average. On one hand, it is possible to have two total eclipses slightly less than 12 months apart. Totality on August 2, 2027, and July 26, 2028, is one example (the two totalities are separated by an annular eclipse in January 2028). On the other hand, a wait of 2.5 years between totalities is not uncommon.

Total Solar Eclipses in North America

Recall that on average, any particular spot on Earth experiences a total eclipse of the Sun only once every 375 years. However, if that ‘spot’ is the size of the North American continent, then your odds of seeing totality are slightly improved. But those odds are still not great, and you will likely have to travel to catch it. Between 2001 and 2050, a total solar eclipse appears over North America a mere six times: 2008, 2017, 2024, 2033, 2044, and 2045. If you want to expand the list to include annular eclipses, then annularity crosses North America seven times between 2001 and 2050: 2001, 2012, 2021, 2023, 2039, 2046, and 2048.

In addition, partial solar eclipses too numerous to mention are visible across North America between 2001 and 2050. If you’d like to explore this topic further, an excellent and comprehensive online resource is EclipseWise by Fred Espenak.

The remote Faroe Islands were one of three locations chosen by TravelQuest as viewing sites for the 2015 total solar eclipse (Photo by Paul Deans/TQ).
The remote Faroe Islands were one of three locations chosen by TravelQuest as viewing sites for the 2015 total solar eclipse (Photo by Paul Deans/TQ).
The dark patch is the Moon’s shadow falling on North America during the August 2017 total eclipse of the Sun (Photo by NASA/DSCOVR EPIC team).
The dark patch is the Moon’s shadow falling on North America during the August 2017 total eclipse of the Sun (Photo by NASA/DSCOVR EPIC team).
After the annular eclipse of 2012, the partially eclipsed Sun set behind a ruined wall in Chaco Canyon Historical Park, New Mexico (Photo by Paul Deans/TQ).
After the annular eclipse of 2012, the partially eclipsed Sun set behind a ruined wall in Chaco Canyon Historical Park, New Mexico (Photo by Paul Deans/TQ).

Join Us to See the Next Total Solar Eclipse

A total eclipse of the Sun is an immersive, emotional event. For mere moments, it engenders a sense of wonder and awe in all who view it. Those who have seen totality will travel thousands of miles to see another just to relive this brief celestial spectacle. TravelQuest has a variety of upcoming total solar eclipse tours in various stages of development: Mexico and Texas in April 2024, Easter Island in October 2024; and Iceland and northern Spain in August 2026. You’ll find TravelQuest at each of these eclipses, perfectly positioned somewhere along the path of totality. Join us, and share in the wonder of a total eclipse of the Sun. Contact TravelQuest today to learn more about our upcoming trips

Totality in 2017. This image reveals detail in the wispy corona, the Sun’s outer atmosphere, that can be seen when it’s observed with binoculars (Photo by Rick Fienberg/TQ).

Header image by Rick Fienberg/TQ

Keep Reading

Blog Archive