You’ve probably heard expressions about things happening once in a blue moon or that there might be a red moon in the fall. These odd colors of the moon might seem like they don’t exist because most people only see the moon in its natural color, but there are times when you can see a different shade of the large rock. The colors are present at times because of the changing atmospheric pressures and other issues that are taking place when the moon is shining. The actual surface doesn’t change colors at all, but people will see the pressures and other details combine to give a perception of the different color. As the moon is rising and setting, it sometimes looks blue because it’s coming through a thicker cross-section of the atmosphere. This means that the blue light is scattered a bit more than red and orange, making you think that there is a blue moon.
A harvest moon is often seen around the autumnal equinox. This is a full moon that sometimes looks deep red. During this time of the equinox, the moon will move along an ecliptic line, focusing the view through a thickened piece of the atmosphere. This makes the moon look red and larger than normal. Sometimes, particles in the atmosphere can get in a position that is just right for people to perceive the moon in different colors, such as orange or a darker yellow.