Amid the hype about a “super blood wolf moon,” there's a legitimately interesting celestial event coming: a total lunar eclipse, which occurs when the sun, moon and Earth line up, with the Earth passing between the sun and the moon.

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A relatively rare celestial treat may be visible this weekend to Washington state residents, and anyone else on the dark side of the Earth with a clear sky. But it isn’t the so-called “super blood wolf moon,” according to one local astronomer.

Yes, there will be a full moon on Jan. 20, according to Woody Sullivan, University of Washington astronomer and professor emeritus. And yes, he said, the first full moon of the year was reportedly called a “wolf moon” by at least one Native American tribe. In addition, the moon will be slightly closer to Earth than usual, making it appear larger.

But none of that is what makes it special.

Sullivan, who objects to the recent trend of naming ordinary full moons and celestial events with words like “super” and “blood,” said there is, however, a legitimately interesting lunar event coming: a total eclipse.

We can see one about every two years on average, Sullivan said.

“This naming of every moon caught on in the last 10 years and it’s driving me crazy,” he said, “but a total lunar eclipse is actually very interesting to see.”

A total lunar eclipse occurs when the sun, moon and Earth line up, with the Earth passing between the sun and the moon. The eclipse will begin Sunday at 6:36 p.m. Pacific Standard Time, reach totality between 8:41 and 9:44 p.m. and be over by 11:48 p.m.

For those who can’t get outside or have their view blocked by clouds, the website Time and Date AS also has what Sullivan calls a surprisingly accurate and interesting simulator of what the eclipse will look like, as well as a livestream feed to watch the eclipse in real time.

While binoculars are nice, people can enjoy watching the lunar eclipse with the naked eye, and — unlike during a solar eclipse — no additional protection is needed, Sullivan said.

As the eclipse starts, viewers will see Earth’s shadow creep across the moon. As it takes over, the moon will go dark, though the edges will be fuzzy.

Once totality occurs, one of three things could happen, and there’s no way to predict which it will be, Sullivan said.

It could become a so-called “blood moon” and take on a reddish cast, he said. It could also turn a coppery red, which Sullivan described “as the most beautiful thing.” It could also take on little to no color, he said.

The outcome depends a great deal on how much dust is in Earth’s atmosphere, he said. The reason there’s any color to the eclipse — or to sunsets and sunrises, for that matter — is because red light makes it through our atmosphere better than blue light, and the light cast on the moon during an eclipse is light that’s peeking around the edges of the Earth through our atmosphere.

So, to recap: The moon will be closer to Earth than usual (a “super moon”). It will be the first full moon of the year (a “wolf moon”). It could look reddish (a “blood moon”). But that last part is because of something much cooler: an eclipse.

Perhaps, Sullivan says, we should focus on that event, and not just on how fancy a name we can give it.