A lunar eclipse and a blood moon are closely related events, but they aren’t exactly the same thing. Most people get confused about these two astronomical events because a blood moon occurs during a certain type of lunar eclipse.
What is the difference between blood moon and lunar eclipse? A lunar eclipse happens when the Earth’s shadow falls on the Moon, blocking sunlight and causing the Moon to darken. However, a blood moon is the special red glow that appears only during a total lunar eclipse. This means all blood moons are total lunar eclipses, but not all lunar eclipses create a blood moon.
Key Areas Covered
1. What is a Blood Moon
– Definition, Features
2. What is a Lunar Eclipse
– Definition, Features
3. Similarities Between Blood Moon and Lunar Eclipse
– Outline of Common Features
4. Difference Between Blood Moon and Lunar Eclipse
– Comparison of Key Differences
5. FAQ: Blood Moon and Lunar Eclipse
– Answers to Frequently Asked Questions
Key Terms
Blood Moon, Lunar Eclipse
What is a Lunar Eclipse
A lunar eclipse happens when the Moon moves into the Earth’s shadow, making the Moon look darkened. This can only occur during a full moon, when the Sun, Earth, and Moon are perfectly or almost perfectly aligned. In this alignment, Earth sits between the Sun and the Moon. These alignments happen about every six months in eclipse seasons.
Unlike a solar eclipse, which is only visible from a small area of the world, a lunar eclipse can be seen anywhere on the night side of Earth. It is also completely safe to view with the naked eye. There is no need for special glasses. A total lunar eclipse can last for up to two hours. This is much longer than a solar eclipse.
Figure 1: Partial Lunar Eclipse
Earth casts two kinds of shadows: the penumbra, which is lighter and larger, and the umbra, which is smaller and much darker. When the Moon passes through these shadows, it creates the different types of eclipses as described below.
Types of Lunar Eclipses
There are three main types of lunar eclipses, based on how much of the Moon enters Earth’s shadow:
1. Total Lunar Eclipse
This happens when the entire Moon passes into the Earth’s darkest shadow, called the umbra. During this, the Moon often turns a reddish color, sometimes called a “blood moon.” This occurs because sunlight bends through Earth’s atmosphere and softly lights the Moon’s surface.
2. Partial Lunar Eclipse
In this type, only part of the Moon moves into the umbra. As a result, only a section of the Moon appears darkened or red, while the rest stays bright.
3. Penumbral Lunar Eclipse
This is the hardest to notice. The Moon passes through the outer shadow of the Earth, called the penumbra. It causes just a very slight dimming that is often invisible without a telescope.
What is a Blood Moon
A blood moon is the dramatic red or coppery glow of the Moon that happens during a total lunar eclipse. This event occurs when the Earth’s shadow completely covers the full Moon, blocking direct sunlight. However, some sunlight still reaches the Moon after passing through Earth’s atmosphere. As the atmosphere filters the light, it scatters blue light and allows only the red and orange wavelengths to reach the Moon. This makes the Moon appear to glow deep red.
Figure 2: Blood Moon
Blood moons don’t happen with every lunar eclipse. Sometimes the Moon only moves partly into Earth’s shadow. This creates a partial lunar eclipse where it looks like a dark “bite” has been taken out of the Moon. In other cases, the Moon passes through only the penumbra, which is so subtle that only experienced skywatchers notice it.
About 29% of all lunar eclipses are total lunar eclipses, and most places on Earth will see one about every 2.5 years. The exact color of a blood moon can vary.
Similarities Between Blood Moon and Lunar Eclipse
- Both are astronomical events involving the Earth, Sun, and Moon aligning in a straight line.
- In both events, the Earth’s shadow falls on the Moon, blocking sunlight.
- Both can only happen during a full moon.
- They are safe to watch with the naked eye.
Difference Between Blood Moon and Lunar Eclipse
Definition
- A lunar eclipse is the overall event that happens when the Earth’s shadow falls on the Moon, blocking sunlight, whereas a blood moon is a specific type of lunar eclipse, which occurs only during a total lunar eclipse when the Moon turns red.
Covering of the Moon
- During a lunar eclipse, the Moon may be partially or fully covered by Earth’s shadow. A blood moon happens only when the Moon is completely covered.
Color of the Moon
- The color of the Moon in a lunar eclipse can range from slightly dimmed to dark red. In a blood moon, the Moon is clearly red or coppery.
FAQ: Blood Moon and Lunar Eclipse
1. What is the difference between a lunar eclipse and a dark moon?
A lunar eclipse happens when the Earth’s shadow falls on the Moon, making the Moon look dark or red. It’s a temporary event that occurs only during a full moon. A dark moon, on the other hand, is simply the new moon phase when the Moon is between the Earth and the Sun.
2. Are blood moons the same as lunar eclipses?
No, blood moons and lunar eclipses are not exactly the same. A blood moon happens during a total lunar eclipse, when the Earth’s shadow completely covers the Moon, and makes it glow red or coppery. A lunar eclipse, on the other hand, can also be partial or penumbral. During these, the Moon only gets slightly darkened and doesn’t turn red.
3. How rare are blood moons?
Blood moons are not very rare. On average, Earth experiences about two lunar eclipses each year, but only about 29% of these are total lunar eclipses, which create blood moons.
4. What happened on 7 September 2025?
On September 7, 2025, there was a total lunar eclipse and a blood moon. During this event, the Moon moved completely into the Earth’s shadow, which made it red or copper. This eclipse was visible in parts of Asia, Africa, Europe, and Australia and lasted for about 82 minutes.
Reference:
1. “Lunar Eclipse.” Wikipedia. Wikipedia Foundation.
2. “Lunar eclipse guide: what they are, when to see them and where.” National History Museum.
Image Courtesy:
1. “Partial lunar eclipse (48302834592)” By Abdalrahman Mohrat from Farasan Island, Saudi Arabia – Partial lunar eclipse (CC BY 2.0) via Commons Wikimedia
2. “Blood Moon during 2018-07-27 Eclipse” By Jacek Rużyczka – Own work (CC BY-SA 4.0) via Commons Wikimedia
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