The Moon into Blood… What does this mean?
Joel 2:  The earth shall quake before them; the heavens shall tremble: the sun and the moon shall be dark, and the stars shall withdraw their shining:  The sun shall be turned into darkness, and the moon into blood, before the great and the terrible day of the LORD come.
Joel 3:  The sun and the moon shall be darkened, and the stars shall withdraw their shining.
Matthew 24:  Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken:
Mark 13:  But in those days, after that tribulation, the sun shall be darkened, and the moon shall not give her light,
Luke 21:  And there shall be signs in the sun, and in the moon, and in the stars; and upon the earth distress of nations, with perplexity; the sea and the waves roaring;
Acts 2:  The sun shall be turned into darkness, and the moon into blood, before that great and notable day of the Lord come:
Revelation 6:  And I beheld when he had opened the sixth seal, and, lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood;
Revelation 8:  And the fourth angel sounded, and the third part of the sun was smitten, and the third part of the moon, and the third part of the stars; so as the third part of them was darkened, and the day shone not for a third part of it, and the night likewise.
The moon will be turned into a Blood Red color, due to the Volcanic Ash in the atmosphere as we look up through the sky on a full moon night. Most of the time, the Moon is a bright yellow color; it’s reflecting light from the Sun. But sometimes the Moon can turn a beautiful dramatic red color. What’s going on?
What causes a red moon? There are few situations that can cause a red moon. The most common way to see the Moon turn red is when the Moon is low in the sky, just after moonrise or before it’s about to set below the horizon. Just like the Sun, light from the Moon has to pass through a larger amount of atmosphere when it’s down near the horizon, compared to when it’s overhead.
The Earth’s atmosphere can scatter sunlight, and since moonlight is just scattered sunlight, it can scatter that too. Red light can pass through the atmosphere and not get scattered much, while light at the blue end of the spectrum is more easily scattered. When you see a red moon, you’re seeing the red light that wasn’t scattered, but the blue and green light have been scattered away. That’s why the Moon looks red. The second reason for a red moon is if there’s some kind of particle in the air.
A forest fire or volcanic eruption can fill the air with tiny particles that partially obscure light from the Sun and Moon. Once again, these particles tend to scatter blue and green light away, while permitting red light to pass through more easily. When you see a red moon, high up in the sky, it’s probably because there’s a large amount of dust in the air.
Volcanoes produce ash and will stay in the sky and cause the light rays reflection from the moon to be a red color.
At the very end of the Great Tribulation Period, there will be a lot of Volcanic Eruptions, which will produce ash clouds of dust and it will stay in the sky for several years. As people look up at the moon at night, the moon will appear to be a Blood red color, because the reflection of the light from the sun onto the moon will change as it is reflected to the earth.
The moon will not really be turned into blood.
The moon will not be affected or changed at all. It’s only the appearance that changes, as we look at it from the earth.
The actual distance varies over the course of the orbit of the moon, from 363,104 km (225,622 mi) at the perigee (closest distance) and 405,696 km (252,088 mi) at apogee (farthest distance), resulting in a differential range of 42,592 km (26,465 mi).
There is nothing on the earth that will cause the moon to turn into real blood!!!
And nothing will truly affect the moon as described in the Book of Revelation from a distance between 225,622 to 252,088 miles away; unless of course the earth explodes!!!
I hope this information helps to understand this saying in the Bible.