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Here’s How to See Comet NEOWISE Over Arizona

Comet NEOWISE in the skies over the western United States earlier this month.
Comet NEOWISE in the skies over the western United States earlier this month. Rocky Raybell/CC BY 2.0/Flickr
Here’s an excuse to dig your binoculars out of the closet and head outside, albeit after the sun goes down. The brightest comet viewable in the U.S. in more than a quarter-century will be streaking through the skies over Arizona through the end of July, and it’s worth seeking out.

Comet NEOWISE, a newly discovered celestial object, is currently passing through our solar system and is awing astronomers and amateur skywatchers alike. But don’t worry, there’s no danger of it hitting the Earth (so you needn’t bother checking your 2020 bingo cards for that particular doomsday scenario).

The retrograde comet, which is officially known as C/2020 F3 (NEOWISE), boasts a large tail and is bright enough to spot with the naked eye (though having a pair of binoculars or a small telescope will afford you a better view).

Comet NEOWISE, which will be visible shortly after sunset each night through the end of the month, was discovered earlier this year by NASA. Amy Mainzer, the University of Arizona’s principal investigator of NEOWISE, says it been a sight to see.

“In its discovery images, Comet NEOWISE appeared as a glowing, fuzzy dot moving across the sky even when it was still pretty far away," Mainzer said in a press release. “As soon as we saw how close it would come to the Sun, we had hopes that it would put on a good show.”

It’s been described as a “once-in-a-lifetime experience,” owing to the fact NEOWISE won’t return to our neck of the galaxy for another 7,000 years (give or take a century). If you’d like to see it, here are some tips and other information about when and where to look.

click to enlarge A composite photo of Comet NEOWISE. - JEAN-DANIEL PAUGET/CC BY 2.0/FLICKR
A composite photo of Comet NEOWISE.

So Why Is It Called Comet NEOWISE?

Basically, it’s named after the instrument that was used in its discovery. On March 27, NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (a.k.a. NEOWISE) space telescope in orbit of Earth first identified the comet.

Just How Big Is It?

According to Joseph Masiero of NASA’s Jet Propulsion Laboratory, NEOWISE is three miles (or five kilometers) in diameter and it's composed of ice, dust, and other interstellar debris.

So When and Where Will Comet NEOWISE Be Visible?

You can check out the comet in the northwest sky nightly after sunset through the end of the month. It will be situated just above the horizon below Ursa Major, better known as the Big Dipper, and will get gradually higher in the sky each night.

NEOWISE will reach its closest point to Earth on July 22 to 23 when it will be approximately 64 million miles away. Astronomers recommend skywatchers try looking sooner rather than later since the comet’s brightness could potentially fade over the next couple of weeks as it moves away from the sun.

What Will Viewing Conditions Be Like?

The current forecast calls for mostly clear skies each night through the end of the month, so you have a decent chance for a clear view of the comet. It’s the monsoon season, though, and late afternoon/early evening storms could possibly occur.

What Time Should You Look?

Astronomers say that Comet NEOWISE will become visible approximately 30 to 60 minutes after sunset as twilight fades.

Where’s the Best Location to Try Spotting the Comet?

Anywhere with a wide-open view of the horizon and little in the way of mountains, trees, or other landmarks blocking things. As with any skywatching, it always helps to be somewhere with as little light pollution as possible, like on the edge of town or out in the boonies. All that said, we’ve seen local folks post on social media how they’ve seen NEOWISE from downtown Phoenix or out in the suburbs. YMMV.

Will You Need a Telescope or Binoculars?

It would help. As we said, NEOWISE has been described as a “naked-eye comet,” but having a decent pair of binoculars (50mm or better) or a telescope at least four inches in length will assist you in getting as close a look as possible.

How Do You Find Comet NEOWISE in the Sky?

It’s recommended that you start by finding the Big Dipper and then sweep the area below the constellation with your binoculars or telescope. You can consult this star chart (or this one) for an idea of where NEOWISE will be each evening.

Are There Any Apps or Websites I Can Use?

Yes. Astronomers swear by the Stellarium website and app (available for both Android and iOS), which allows users to locate planets, stars, and other objects in the heavens. Just input the date you’d like to go skywatching and it will pinpoint the comet as seen from your location.

So What’s It Going to Look Like?

As you can tell by the photos above, NEOWISE has a prominent tail, which is caused by the cloud of dust and vaporized gasses bleeding off the comet by solar radiation.

“This very close passage by the sun is cooking the comet’s outermost layers, causing gas and dust to erupt off the icy surface and creating a large tail of debris,” NASA officials said in a press release. “And yet the comet has managed to survive this intense roasting.”

In other words, be on the lookout for NEOWISE’s tail. To the naked eye, it will appear somewhat fuzzy, but those with binoculars or a telescope will get a sharper view.
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Benjamin Leatherman is a staff writer at Phoenix New Times. He covers local nightlife, music, culture, geekery, and fringe pursuits.