Black Moon: What Is It And How Often Does It Happen?
On August 23, 2025, a Black Moon will occur. Let’s explore what a Black Moon is, and why stargazers should enjoy them. Also, download Sky Tonight to conveniently track all the New Moons and Full Moons with a handy lunar calendar.
Contents
What is a Black Moon?
The lunar calendar closely aligns with Earth's calendar year. That’s why we usually have one Full Moon and one New Moon each month. Occasionally, there can be the second New Moon within a single calendar month, which can be called a calendrical Black Moon.
Alternatively, a Black Moon can be seasonal, when an extra New Moon occurs in an astronomical season. Typically, each season contains three New Moons, but when a season experiences four New Moons, the third one is designated as a Black Moon.
Also, this expression is used when there’s no New Moon in a month. This can only happen in February because it is the only calendar month that is shorter than a lunar month.
Is Black Moon a Full Moon?
Rarely, a Black Moon refers to an event when there’s no Full Moon in a month. This occurs once every 19 years: the last time was in 2018, and the next time will be in 2037.
Is New Moon the same as Black Moon?
Some people say “Black Moon” to denote every New Moon, not just a specific one, because, in this phase, the Moon is unlit and invisible. However, the definitions listed above are used much more often.
How to see a Black Moon?
A Black Moon is not the best object for observation. According to the definitions above, a Black Moon is a particular New Moon. During its new phase, the Moon always faces the Earth with its unlit side and therefore is invisible to us. In other words, you can’t see a Black Moon. The most attentive observers might only notice the disappearance of the stars occulted by the lunar disk in the night sky.
Although we cannot see the Moon itself on the Black Moon night, we can take advantage of that time to see many other celestial objects in the sky: the New Moon is considered the best time to observe planets, stars, deep sky objects and the Milky Way.
There is only one way to see a New Moon or a Black Moon, and we’ll discuss it later.
When is the next Black Moon?
It’s hard to say when the next Black Moon will occur because this definition isn’t fixed and might refer to different Moon phases. Here are all the possible answers depending on the definitions mentioned above:
- The New Moon of August 23, 2025, might be called Black as it will be the third out of four New Moons of that season;
- On August 31, 2027, we’ll see the Black Moon, which is the second New Moon in a single calendar month;
- There will be no New Moon in February 2033, which falls under the third definition of Black Moon given above. By the way, this is an extremely rare event – next time it will only occur in February 2052!
How often does a Black Moon occur?
Black Moons are rather rare. Calendrical Black Moons occur roughly every 29 months, making it the most common type of Black Moon. Seasonal Black Moons occur approximately once every 33 months. The third type of a Black Moon, when there is no New Moon in the month, is extremely rare: it only happens once every 19 years.
Three Black Moons
In the first three months of 2033, most of the globe will have three Black Moons in a row. That year, the New Moons of January 30 and March 30 will be the second in a month, and in February, there will be no New Moon.
Black Super Moon
A Supermoon occurs when the New or Full Moon coincides with the perigee – the Moon’s closest approach to the Earth. But can a Supermoon also be a Black Moon? Yes!
On August 20, 2028, the third New Moon of the season will approach the Earth closer than usual. Although the event will not be observable, like any other New Moons, “Black Super Moon” still sounds intriguing, doesn’t it?
Black Moon and Dark Moon
Unlike “Black Moon”, the term “Dark Moon” may refer to any New Moon as it denotes the period when the Moon is in conjunction with the Sun and is invisible to the naked eye. Astronomers of the past used the term “New Moon” to denote both the waxing crescent and a completely dark lunar disk. Not to get confused, they would say "Dark Moon" when referring to the unlit Moon. The term is sometimes used nowadays.
Black Moon: to sum up
"Black Moon" is not a unified term used in astronomy. It can define the second New Moon in a calendar month, or the third New Moon in an astronomical season. Sometimes this expression is used when there’s no New Moon in a month. The next Black Moon will occur on August 23, 2025. For an observer, a Black Moon is not any different from some other New Moon. By the way, some astronomers specifically plan their observations around the New Moon, because dim objects such as stars, planets, nebulae, and galaxies are better seen in a moonless sky. You can follow their lead and track the phases of the Moon with the easy-to-use calendar in the Sky Tonight app.
We wish you clear skies and happy observations!
