Solar Eclipses – Types: Total, Annular, Partial, Hybrid Solar Eclipse

Types of Solar Eclipses

Eclipses of the Sun come in four different flavors. There’s the relatively common partial eclipse, and the extremely rare hybrid. In between, in terms of frequency of occurrence, are the much-sought-after total and annular solar eclipses. For many people, watching the Sun vanish from the sky during a total eclipse of the Sun is a very emotional experience.

An annular solar eclipse sometimes evokes less emotion, as the Sun never entirely disappears from view: the edge remains visible, known commonly as the “Ring Of Fire”.

Hybrid solar eclipses are unusual and very infrequent. A partial solar eclipse accompanies all total, annular, and hybrid eclipses, but it also occurs by itself. Here’s what you need to know about these four solar eclipse variants.

What is a Solar Eclipse?

Simply put, a solar eclipse happens when the Moon covers at least a tiny fraction of the Sun’s surface. For this to occur, the Sun, Moon, and Earth must be aligned, which means a solar eclipse can take place only during a new Moon phase. 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 larger than the Moon, it’s also 400 times farther away. So on average, both appear to have the same apparent diameter—they look to be the same size. 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 solar eclipse occurs. If the alignment is perfect, but the Moon’s apparent size is slightly smaller than the Sun’s, the result is an annular solar eclipse. A hybrid eclipse happens when the eclipse changes from annular to total (or vice versa) along the eclipse path.

If you happen to be on the centerline path of one of these three eclipse types, you’ll also experience partial eclipses before and after the ‘main event.’ But if the alignment is not perfect, a partial eclipse is the only outcome, because the Moon covers only part of the Sun’s surface.

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—it’s not possible to have two total eclipses back to back. There are always at least two solar eclipses per year; five in any one year is possible, but extremely rare. Over a 5,000 year period, the occurrence of three of the four solar eclipse types is quite even: 35% are standalone partials, 33% annulars, and 27% totals. To emphasize their rarity, less than 5% of all solar eclipses are hybrid.

Four Types of Solar Eclipse

A total solar eclipse is one of nature’s grandest sights. Words are inadequate to describe it; photographs can’t do it justice. Seeing totality is an experience unlike any other. First-time eclipse chasers are often completely unprepared for the emotions that overwhelm them when the Sun vanishes from the sky.

This incredible sight is the culmination of a perfect cosmic alignment—the Moon passing directly across the face of the Sun and having a slightly larger apparent diameter than Sol’s. This larger apparent diameter means the Moon can completely cover the solar disk, and the result is totality.

When the Moon and Sun are in perfect alignment, amazing sights emerge to delight eclipse watchers standing in the umbra—the dark lunar shadow. Two “diamond rings” herald the beginning and end of the total eclipse. Giant red arcs of gas erupting from the solar surface are visible as daylight fades. The corona, the Sun’s pale white, gossamer outer atmosphere, glows brightly during totality, surrounding the ‘hole’ in the sky where the Sun once shone.

Around the horizon is a sunset glow, while the sky overhead has gone dim, revealing the brightest planets and stars. But then, all too soon, it’s over. Totality can last no longer than 7.5 minutes; almost all are much shorter.

When sunlight emerges as totality ends, delighted eclipse watchers always ask: When and where is the next total eclipse? To learn more about totality, visit our blog “What is a Total Solar Eclipse?“.

An annular solar eclipse is the end result of a not-quite-perfect celestial configuration. As with a total eclipse, the Moon and Sun are in perfect alignment. But during an annular, the apparent diameter of the Moon is less than the Sun’s. As a result, the Moon appears too small to cover all of the brilliant solar disk, and the lunar shadow that reaches Earth is called the antumbra. At mid-eclipse (annularity), a brilliant ring of sunlight surrounds the Moon, which leads to the nickname “Ring of Fire” for annular eclipses.

From beginning to end, much of the annular eclipse sequence is the same as for a total. It still takes more than an hour for the eclipse to proceed from first to second contact. The light still fades somewhat as the eclipse progresses.

With solar filters firmly in place (they can never be removed during an annular eclipse), observers can watch Baily’s Beads pop on and off at second and third contacts. And there is something very eerie about seeing the Sun with a gaping hole in its midsection during annularity. More details about this type of eclipse can be found in our blog “What is an Annular Eclipse?“.

A hybrid solar eclipse is a true oddity. It’s called ‘hybrid’ because it involves some combination of annularity and totality along the centerline path of the eclipse.

More than 90% of hybrid eclipses begin as annulars, become total and remain so along much of the track, and then revert to annular at the end of the eclipse path. These are sometimes referred to as ATA hybrids. The other hybrid types either start as total eclipses and end as annulars (TA), or begin as annulars and finish as totals (AT). All are rare—only seven hybrid eclipses occur this century, with the three most recent being 2013, 2023, and 2031.

A hybrid eclipse results when the tip of the Moon’s dark umbral shadow touches Earth’s surface at some points, but falls short of the surface at one or both ends of the eclipse centerline. For example, during an ATA hybrid eclipse, Earth’s curvature causes the middle section of the eclipse track to be closer to the umbral shadow (hence totality) than the beginning and end of the track, where the Earth curves away and the umbra doesn’t quite reach our planet (hence annularity). So the eclipse is seen as either annular or total, depending on where an observer is located on the centerline.

There are two varieties of partial solar eclipses—those that accompany total, annular, or hybrid eclipses, and those that stand alone.

In all cases, ‘partial’ means the Moon covers only part of the Sun. For those observers positioned along the centerline of a total, annular, or hybrid eclipse, the partial phases precede and follow totality or annularity. But if the Sun-Moon-Earth alignment is not perfect, or if the observer is not on the centerline of a total or annular, then a partial eclipse of the Sun is the result.

Solar Eclipse Viewing

When observing a solar eclipse, eye safety is paramount. With one exception, it is never safe to look at, or photograph, any aspect of a solar eclipse without using a safe solar filter. That exception is during the few minutes of totality, when the Sun’s face is completely hidden by the Moon. Our blogs “How to Safely Watch a Solar Eclipse” and “Taking Pictures of the Eclipse Safely” provide more details on these topics.

To witness a total or annular eclipse, you’ll more than likely have to travel. Why not join TravelQuest on one of our upcoming solar eclipse trips? There is a solar eclipse somewhere on Earth once every 18 months or so. Come with us as we pursue totality, no matter where in the world it takes us, and seek out particular annular eclipses in locations that fascinate us.