The reason for the full diet of the moon is that the sun, the earth, the moon, is precisely organized in a straight line in space, and the moon is fully integrated into the earth's native area. It's like a simple geometric game, and behind it are the smart rules of how the universe works。
Triple geometric game
The moon itself does not glow, and the light we see is a reflection of the sun. When the full moon is eaten, the earth happens to be between the sun and the moon, and the three are almost fully aligned, and the shadow of the earth is projected on the moon. But here's the key detail: the orbital plane around the earth (the white track) does not overlap with the orbital plane around the earth (the ecstasy) and there are about 5. 15 degrees of a patch。
It's this little tip, and it's not gonna happen every month. In most full moons, the moon slips from the “top” or “lower” of the earth, and only when the full moon happens to be near the intersection of the two orbital horizons can the common thread be refined so that the moon remains in the shadow of the earth。
The shadows of the earth themselves are stratified: the darkest is the area where the sun's light is completely covered, and the half of the shadows on the periphery are only partially covered. The full moon is the moment when the moon fully enters the picture。
Red filters in the atmosphere
If it is simply swallowed by shadow, the moon should disappear from the night sky. But the most fascinating scene of the full moon is that the moon becomes dark red or copper, that is to say, “red moon” or “blood moon”. It is not the moon itself, but the atmosphere of our planet that plays a key role。
The sun is made up of many colors. As the sun passes through the earth's thick atmosphere, the shorter-length blue, purple light is easily dispersed across the atmosphere by atmospheric molecules and small dust, while the longest-length red light penetrates the strongest and can move forward. The red light is like a giant filter, repeated by the earth's atmosphere, bent and lighted on the surface of the moon in the shadow。
So what we see is the “blood moon”, which is actually all the red light that gathers together at sunrise and sunset on earth, projected collectively on the moon. The depth of its colour — from bright orange red to dark brown red — depended on the amount of clouds, dust and even ash in the earth's atmosphere at that time。
Coincidence superimposed
Because of the demanding geometry, the full monthly diet itself is not frequent. Astronomical statistics show that, at the global level in the twenty-first century, the total monthly diet takes on average about 14 months, but for a specific location on earth it takes on average about three years to see it。
Even more rare is that the full monthly diet always occurs on the day of the full full moon, but the full moon may appear on any day of the fourteen to seventeenth calendar. The new year's eve was fixed at 15 months, which further reduced the probability of the two encounters. Combining these factors, it is extremely unlikely that the full monthly diet will fall at midnight。
Throughout the twenty-first century, only five such coincidences occurred: 2007, 2008, 2026, 2054 and 2072. Among them, the whole of the month of march 3, 2026 was an extremely rare observation for the public in our country。
