PORTLAND, Ore. — You'll want to point your eyes to the sky this week. That's because the full moon will also be a blue moon and a supermoon.
While supermoons are more common, a blue moon, on average, occurs once every two or three years. Having both of them happen at the same time only comes about once every 10 to 20 years, according to NASA. After this week, the next blue supermoon will occur about 13 years from now in January 2037.
Here's what to know about the celestial event.
What is a blue supermoon?
Despite its name, blue moons don't change color. A blue moon is simply the second full moon within a month. It's something that occasionally happens because the moon's 28-day cycle doesn't always align with the 30 or 31-day calendar. The term is also used to describe the third full moon in a season with four full moons.
'Supermoon' is less of a scientific term and more of a popular one. These moons are dubbed supermoons because they are closer to Earth than usual. They can also be 30% brighter than average.
When is the blue supermoon?
The moon will appear full for three days through early Wednesday morning. The moonrise will be at 9:16 p.m. on Wednesday, according to timeanddate.com.
Will I be able to see it in the Pacific Northwest?
Clouds are in the forecast for parts of Oregon and southwest Washington, but there won't be an opaque blanket of clouds everywhere, so stargazers have the chance to see the blue supermoon, according to KGW meteorologist Chris McGinness.
The Associated Press and TEGNA Digital Content Producer Chris McCrory contributed to this report.
