People in the western United States are getting ready for this Sunday's solar eclipse.

Experts say If it the weather's clear, it'll be hard to miss.

Sunday's eclipse will be an annular eclipse.

That's when the sun and moon align and the moon appears smaller than the sun.

The best viewing will be the southwestern United States.

Yet, we should be able to see it here in Montana around 7:30 in the evening.

Eclipses like this happen just once every 18 years.

"It comes into direct line with the sun, at least, if you're in the right part of the Earth, you'll see it come right across the center. But it's an Annular, meaning that there will be a ring of the sun visible all the way around it and it won't get totally dark," says MSU Physics Professor Dana Longcope.

As a reminder, if you want to watch the eclipse be sure to wear dark glasses to protect your eyes.