A rare solar eclipse is happening in the US this weekend and 68 million Americans have the chance to see it. Here's when, where, and how to see this spectacular 'ring of fire' safely.

• An annular solar eclipse will cast a shadow on the sun and make a "ring of fire" in the sky October 14.
• In the western US, about 68 million people have a rare opportunity to see this eclipse.
• Here's what causes a solar eclipse, how often they happen, and how to watch without burning your eyes.

A solar eclipse is coming to the western US this Saturday, October 14. It will begin in southwestern Oregon at 9:13 a.m. PDT and end in southern Texas at 12:03 p.m. CDT, according to NASA.

Therefore, if you are one of the millions in its path, what time you can see the spectacular ring of fire will depend on where you're located.

The entire event will take place over about 2.5 hours, as the moon crosses between the Earth and sun, eclipsing the sun as it goes. But only a brief window within that time frame will be when the ring of fire appears when the moon has nearly completely eclipsed the sun.

Here's a quick snapshot of when the eclipse starts and when it reaches annularity (aka the ring of fire) for certain cities in each of the six states it will cross:

NASA also released the map below of where in the US it will occur. People located within the shaded band will be able to see the ring of fire.

But, as the map shows, even if you're not located within the prime path of annularity, you'll still be able to see a partial solar eclipse. For example, people in central Colorado will see 80% of the sun eclipsed while those in northeastern New York will see 20%.

To figure out exactly when the eclipse happens for you and how much of the sun will be eclipsed in your location, visit NASA's website, which has an interactive calculator.

It's worth stepping outside for a moment to glimpse this event since it may be your last opportunity to see the sun swallowed in shadow for two decades.

If you'd like to try to see it no matter where you are in the continental US, try looking outside around 12:35 p.m. ET / 11:35 a.m. CT / 10:35 a.m. MT / 9:35 a.m. PT.

"It's going to be absolutely breathtaking for science," Madhulika Guhathakurta, an astrophysicist specializing in the sun at NASA, said in a briefing about the upcoming celestial event.

No doubt the eclipse will be breathtaking for viewers on the ground, too. Here's everything you need to know before the sun goes dark.

What an annular solar eclipse is, and what causes it

A solar eclipse occurs when the moon passes between the sun and Earth, blocking the sun from our view for a few fleeting minutes. When everything lines up just right, with the moon at the right distance to cover the sun's entire disc, we get a total solar eclipse.

The eclipse on October 14, however, will be an annular solar eclipse. That's because the moon will be in the distant part of its orbit, appearing smaller in the sky and not fully covering the sun. It will leave a "ring of fire" protruding around its shadow, and the sky won't go completely dark.

The ring of fire comes from the sun's chromosphere, a layer of its atmosphere where hydrogen atoms emit a reddish light.

"That's what makes it so beautiful," Guhathakurta said.

Solar eclipses happen every year, but seeing them is rare

Some kind of solar eclipse happens about two to five times per year, according to the Natural History Museum. A total eclipse occurs roughly every 18 months.

They're often over the ocean or unpopulated places, though. It's rare to have an eclipse near you.

Any one spot on Earth gets a total solar eclipse every 400 years, according to the museum.

The US gets its next eclipse in April 2024. That eclipse will be total, and it will cut across the eastern US from Texas to Maine.

After that, the contiguous US won't see another total solar eclipse until 2044, or an annular eclipse until 2046.

Where to see the solar eclipse and stand in its 'umbra'

The umbra, aka the moon's shadow, is the place to be. That's where you can see the annular eclipse and the ring of fire.

The umbra will carve a narrow path across the western US, from the Oregon coast to Corpus Christi, Texas.

About 68 million people live within a two-hour drive of the eclipse's path, according to Alex Lockwood of NASA's Science Mission Directorate. She added that the entire contiguous US will be able to see a partial solar eclipse, though the moon may just barely overlap the sun in many places.

NASA created a detailed map, below, to show where exactly the umbra of the October eclipse will fall — that's the diagonal line on the western side of the country — as well as the 2024 total eclipse on the eastern side of the country.

How to view a solar eclipse without burning your eyes

If you look at a solar eclipse with no protection, you could damage your eyes. That's because the sun's ultraviolet radiation can burn your retina, causing permanent damage within about 100 seconds, according to NASA. Since there are no pain receptors in your retina, you may not notice the damage until it's too late.

So don't look directly at the sun, even during the peak of an annular eclipse.

Instead, get a pair of eclipse glasses or a handheld solar viewer online or from your local planetarium, which could be hosting an eclipse-watching event if it's in the path of the umbra.

Make sure the solar filter in your glasses or handheld viewer has an ISO 12312-2:2015 certification. The manufacturer's name and address should be visible on the product, too.

The National Park Service advises against using any solar filter that's torn, scratched, wrinkled, coming loose from its frame, or made before 2015.

Do not look at the sun through a camera, telescope, or binoculars, even if you're wearing eclipse glasses or using a handheld solar filter. According to NPS, "the concentrated solar rays will damage the filter and enter your eye(s), causing serious injury."

If you don't have a solar filter, you can use a technique called pin-hole projection to watch the eclipse unfold.

You can do this with your hands, according to NPS: "Cross the outstretched, slightly open fingers of one hand over the outstretched, slightly open fingers of the other hand. With your back to the sun, look at your hands' shadow on the ground. The little spaces between your fingers will project a grid of small images on the ground, showing the sun as a crescent during the partial phases of the eclipse."

Or you can follow NASA's guide to make a projector out of card stock and aluminum foil. You can even use a kitchen colander to project a pinhole and watch the moon creep across the sun.