A lunar eclipse happens when Earth’s shadow falls on the full moon, while a solar eclipse happens when the Moon’s shadow falls on Earth at new moon. A lunar eclipse is safe to watch from about half of Earth, while a total solar eclipse needs eye protection and is seen only from a narrow path.
Key facts
- Lunar eclipse: Sun, Earth, Moon in a line at full moon. Solar eclipse: Sun, Moon, Earth in a line at new moon.
- Lunar totality can last up to about 1 h 46 min; solar totality lasts only minutes at any one place.
- Worldwide, the two are about equally common: NASA lists 228 lunar and 224 solar eclipses in 2001–2100.
- Lunar eclipses are safe to watch; solar eclipses need ISO 12312-2 solar viewers except during totality.
What are the main differences between a lunar and a solar eclipse?
Lunar and solar eclipses differ in seven ways: the alignment, the moon phase, who can see them, how long they last, how often they happen, eye safety and appearance.
| Difference | Lunar eclipse | Solar eclipse |
|---|---|---|
| 1. Alignment | Sun, Earth, Moon: Earth in the middle | Sun, Moon, Earth: the Moon in the middle |
| 2. Moon phase | Full moon | New moon |
| 3. Who can see it | Anyone on Earth’s night side with the Moon above the horizon, about half the planet | Totality only inside a narrow path; a partial eclipse over a wider region |
| 4. Length of totality | Up to about 1 h 46 min | A few minutes at any one place; 6 min 39 s was the longest of 2001–2100 |
| 5. How often (2001–2100) | 228 eclipses, 85 of them total | 224 eclipses, 68 of them total |
| 6. Eye safety | Safe with the naked eye | ISO 12312-2 solar viewers needed except during totality |
| 7. Appearance | The Moon darkens and turns red, orange or brown | The Sun is covered; the sky darkens and the corona appears in totality |
Which body is in the middle?
In a lunar eclipse Earth is in the middle, and in a solar eclipse the Moon is in the middle.
During a lunar eclipse, Earth sits between the Sun and the Moon and casts its shadow onto the Moon. Earth’s shadow at the Moon’s distance is more than twice as wide as the Moon, so the whole Moon can stay inside it for well over an hour. Our lunar eclipse guide lists the dates and types of upcoming ones.
During a solar eclipse, the Moon sits between the Sun and Earth and casts its shadow onto Earth. The Moon is far smaller than Earth, so the dark inner part of its shadow covers only a narrow strip of the planet’s surface.
Which moon phase does each eclipse need?
A lunar eclipse needs a full moon and a solar eclipse needs a new moon, because only at those two phases do the Sun, Earth and the Moon fall into a line.
At full moon, the Moon is on the far side of Earth from the Sun, so Earth’s shadow points toward it. At new moon, the Moon is between Earth and the Sun, so its shadow points toward Earth. The other six phases of the moon cannot produce an eclipse.
Most full and new moons still miss, because the Moon’s orbit is tilted 5.14° to Earth’s orbit. An eclipse needs the full or new moon to fall near one of the two crossing points, which happens in eclipse seasons about every 173 days. To see when the next chances come, check the next full moon and the next new moon.
Who can see each eclipse?
Everyone on Earth’s night side with the Moon above the horizon can see a lunar eclipse, but a total solar eclipse is visible only from inside the Moon’s narrow shadow path.
A lunar eclipse happens on the Moon itself, so every observer who can see the Moon sees the same thing at the same moment. NASA notes that each lunar eclipse is visible from half of Earth.
A solar eclipse depends on where you stand. Inside the path of totality, the Moon covers the Sun completely. On either side, a much wider zone sees a partial eclipse, with only part of the Sun covered. Outside that zone, nothing happens at all.
This explains why solar eclipses feel rarer. Worldwide, the two types occur about equally often. A total lunar eclipse simply comes to wherever the Moon is up, while a total solar eclipse usually means traveling to the path. The total solar eclipse of 2 August 2027 is a good example: its path is only about 258 km (160 mi) wide at most.
How long does each eclipse last?
Totality in a lunar eclipse can last up to about 1 hour 46 minutes, while totality in a solar eclipse lasts only a few minutes at any one place.
The longest total lunar eclipse of the 20th century, on July 16, 2000, lasted 1 h 46 min 24 s. With the partial phases included, a lunar eclipse can stay visible for more than 3½ hours.
The Moon’s small shadow races across Earth’s surface, so any one spot stays inside it only briefly. The longest total solar eclipse of 2001–2100, on July 22, 2009, reached 6 min 39 s. Many are much shorter: the total eclipse of August 12, 2026 offered at most 2 min 18 s.
How often do lunar and solar eclipses happen?
Lunar and solar eclipses are about equally common worldwide, with two to four of each in every year of the 21st century.
| Eclipse type (2001–2100) | Lunar | Solar |
|---|---|---|
| Total | 85 | 68 |
| Partial | 57 | 77 |
| Penumbral | 86 | none |
| Annular | none | 72 |
| Hybrid | none | 7 |
| All eclipses | 228 | 224 |
The difference is in what one observer sees. A lunar eclipse is visible from half of Earth, but a given town sees a total solar eclipse only rarely, and many places wait centuries between two of them.
Do you need eye protection?
You need eye protection for a solar eclipse but not for a lunar eclipse.
A lunar eclipse is safe to watch with the naked eye, binoculars or a telescope, because you are looking at the shadowed Moon. A solar eclipse means looking toward the Sun itself. NASA’s safety advice is:
- Use solar viewers or eclipse glasses that meet the ISO 12312-2 international standard.
- Regular sunglasses, however dark, are not safe for looking at the Sun.
- Remove protection only during totality, when the Moon completely covers the Sun’s bright face.
- Cameras, binoculars and telescopes need a solar filter on the front; eclipse glasses alone do not protect you through optics.
- A pinhole projector lets you watch the Sun’s image on a surface instead.
What does each eclipse look like?
A lunar eclipse turns the Moon dark and then red, while a total solar eclipse turns day into deep twilight and reveals the Sun’s corona.
During a lunar eclipse, a dark curved shadow creeps across the Moon. At totality, the Moon glows red or orange because Earth’s atmosphere bends red sunlight into the shadow. That glow is the reason a total lunar eclipse is called a blood moon.
During a total solar eclipse, the Sun shrinks to a thin crescent and the light turns dim and strange. At totality, the sky darkens, bright planets and stars appear, and the pale corona spreads around the black Moon.
What are annular and hybrid solar eclipses?
An annular solar eclipse happens when the Moon is too far from Earth to cover the Sun completely, leaving a bright ring; a hybrid eclipse changes between annular and total along its path.
Annular eclipses happen when a new moon falls near apogee, the Moon’s farthest point from Earth. The Moon then looks slightly smaller than the Sun, and a “ring of fire” surrounds it. An annular eclipse is never safe to watch without a solar filter, because part of the Sun stays uncovered.
Lunar eclipses have no annular type. Earth’s shadow at the Moon’s distance is always wider than the Moon, so a well-aligned Moon is always fully covered. The faint penumbral eclipse is the lunar type with no solar match.