The night sky is set to welcome the “super blue moon,” as a relatively rare celestial phenomenon appears in the sky.
This event occurs when a blue moon combines with a supermoon. Some consider it a rare and potentially symbolic phenomenon, while others simply use it as an opportunity to look up and recognize our closest neighbor, the Moon.
Here’s everything you need to know about this month’s super blue moon, including why it won’t be blue at all.
What is a supermoon?
The term “supermoon” refers to the moment when the moon is at its closest point to Earth, and therefore appears a little bigger and brighter than usual. While the term could theoretically apply to any time the moon reaches this point — called perigee — it’s most commonly used when the moon is full, as it will be tonight.
What is a blue moon?
There are two ways to define a blue moon, which are similar but different. The first is when a full moon appears twice in the same calendar month, and the other is the third full moon of an astronomical season, which falls between the equinoxes and solstices.
The first definition is the most common, but this month’s blue moon falls under the second. The last of these super blue moons occurred last August.
Blue moon does not mean that the moon is blue. Although this can sometimes happen, the commonly used definition actually has nothing to do with the color of the moon itself.
What is a super blue moon?
It’s simply a combination of the two. It’s unclear exactly how often this happens — partly because neither supermoon nor blue moon are precise or scientific terms — but it’s relatively rare.
Why is this super blue moon special?
Perhaps the most notable feature of tonight’s Moon isn’t that it’s blue or super bright. It’ll be orange or red instead.
This is the result of wildfires in North America. They release dust and small particles that get trapped in the atmosphere, scattering light and giving the sky and the Moon a redder and darker color.
This will be even more evident when the Moon is low in the sky, as light has to pass through Earth’s atmosphere, making it appear more orange. A similar effect is responsible for the deep red color the Moon takes on during a lunar eclipse, which is why it is sometimes referred to as a “blood moon.”
Does the Super Blue Moon Mean Anything?
Not scientifically speaking. Beyond the two facts that make this a super blue moon—namely, that it’s the third full moon of an astronomical season and that it’s a bit closer than usual—there’s nothing astronomically notable about tonight’s moon.
In reality, the Moon is only slightly larger than normal, and the fact that it is blue is just a quirk of the lunar calendar. The Moon itself has not changed, nor should it have any significant effects on Earth.
Some people choose to give it meaning, however, and astrologers have suggested that it may be remarkable. These claims have no scientific basis, but they can be fun to read.
How do you see the super blue moon?
Like any other moon: go out and observe it. Its relatively large size and the fact that it is full should mean that it is easy to see and spectacular when you do, and you should be able to spot its red color.
Experts advise viewing the moon at sunrise or sunset, as the contrast with objects on the horizon means it should appear larger and more spectacular to see. But other than that, nothing special is required to observe it: unlike many other celestial spectacles, it does not require special equipment or much waiting.
The full moon will peak at 7:25pm Monday night, although it will of course remain largely full for the next few hours and days. The moon rises around 9pm and sets around 6:30am Tuesday morning.
But the weather could prove to be a hindrance, at least in the UK. The sky is expected to be cloudy, which could block the view, but it is likely to be seen at some point in the evening.
