- What is a blood moon?
- How often is there a blood moon?
- Why is it called "blood moon"?
- What happens when there is a blood moon?
- Is it dangerous to look at a blood moon?
We explain what the blood moon is, how often it occurs and the origin of its name. Also, why is it not dangerous to look at it.
What is a blood moon?
It is popularly known as red moon or blood moon to a type of lunar eclipse, in which the satelite terrestrial does not darken completely, but acquires certain shades of copper, red or brown. This phenomenon occurs when two different events coincide:
- when there is a eclipse total of Moon, that is, when in a full Moon period, the Land stands between the sunlight and the terrestrial satellite, submerging the latter in a cone of almost total shadow.
- When the atmosphere terrestrial contains high levels of pollution, cloudiness or other types of interference, capable of absorbing certain wavelengths of sunlight and allowing only the lower spectrum of light, that is, red light, to pass through.
When both situations coincide, we have a red moon or blood moon, that is, an eclipse of the Moon that instead of completely obscuring it, dyes it a reddish tone that can be overwhelming. For the rest, this phenomenon does not have any particularity or special feature from an astronomical point of view, but it has been observed since ancient times and has been commonly associated with bad omens.
How often is there a blood moon?
The "blood moons" are not entirely predictable, since they depend on the date and the place from which they can be perceived. After all, it is a lunar eclipse, nothing more. Between two and five lunar eclipses occur each year, although total eclipses are the least frequent of all.
Even so, the odds are that the next red moons will be on the following dates and places:
- May 16, 2022, visible in North and South America, Europe, and Asia.
- November 8, 2022, visible in North and South America, Asia, Australia, and the Pacific.
- March 14, 2025, visible in North and South America, Europe, Australia, and the Pacific.
- September 7, 2025, visible in Europe, Africa, Asia and Australia.
- March 3, 2026, visible in North and South America, Asia, Australia, and the Pacific.
- December 31, 2028, visible in Europe, Africa, Asia, Australia and the Pacific.
- June 26, 2029, visible in North and South America, Africa, Europe, and the Middle East.
- December 21, 2029, visible in North and South America, Asia, Europe, Australia, and the Pacific.
- April 25, 2032, visible in North America, Asia, Africa, Europe, and the Pacific.
- October 18, 2032, visible in North and South America, Asia, Africa, Australia, and the Pacific.
Why is it called "blood moon"?
There are many explanations and stories of why this type of moon is called a "blood moon", all associated with tragic or bloody events. In the Antiquity they were associated with dire events that threatened the stability of the universe or the perpetuity of a monarch.
Some biblical versions associate it with the death of Saint John the Baptist, when the exotic Idumean princess Salome asked King Herod as a gift, after having performed a dance for him, the head of the prophet John the Baptist on a silver platter.
The monarch, who had had the prophet arrested to prevent him from turning the people against him (in some versions, because he did not approve of Herod's marriage to his sister Herodias), kept his word and the prophet's severed head entered the dancer , and just that night the Moon was dyed red, thus reflecting the holy blood shed.
What happens when there is a blood moon?
When there is a blood moon, a reddish, brown or coppery Moon can be seen, because the light of the SunWhen it enters the Earth's atmosphere, it is dispersed or distorted when it comes into contact with the particles suspended in it, such as ash, carbon dioxide, very dense clouds, among others.
This is because red and orange light have the longest wavelength and the slowest frequency, oscillating 430 to 510 times per second. Otherwise, this moon is no different from any other in the lunar calendar.
Is it dangerous to look at a blood moon?
Absolutely. Unlike the solar eclipses, capable of damaging our retina if we look at them directly, lunar eclipses do not represent any danger, since the Moon has no brightness of its own. Its apparent brightness is due to the reflection of sunlight.