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What to know before you go comet-hunting

This summer’s sky spectacle is a shooting star that was discovered in March by NASA’s Near-Earth Object Wide-Field Explorer, or NEOWISE. Comet NEOWISE (also known as C/2020 F3) zoomed around the sun last week, and is now visible to the naked eye. But only if you know exactly where, when and how to look.

Although there’s lots of buzz about NEOWISE, this is no “great comet” — just a pretty good one. If you’re expecting to look up above your head and see a celestial portent of “Game of Thrones” proportions, you’re going to be disappointed.

But if you’re angling to see this season’s most-talked-about sky show with your own eyes, here are five strategies to maximize your chances:

Go late or go early: Because it’s so soon after the northern solstice, the celestial alignments make it theoretically possible to see Comet NEOWISE in morning or evening skies, with emphasis on the word “theoretically.”

For the next few days, the comet will be higher in the sky in the morning, which means predawn viewing is preferred. The best time is around 3 to 4 a.m.; the farther north you are, the earlier you should get up. Around July 15, the comet’s outward trajectory from the sun will turn it into more of an evening star, with prime time coming at 10:30 p.m., about an hour and a half after sunset.

Look north: Your viewing spot should have an unobstructed view to the northern horizon — to the northeast for morning viewing, or to the northwest for the evening. To find optimal views of the horizon, scan Google Maps (with Street View). And to figure out exactly where to look in the sky, study the charts from Sky & Telescope, SpaceWeather.com, The Sky Live, Heavens Above and EarthSky.

Comet NEOWISE should be visible in the northeast by 3 a.m. July 11 — close to the horizon and to the left of Venus, the brightest object in eastern skies.

Seek clarity: The fact that NEOWISE is so close to the horizon means that sky conditions are crucial. There’s a good chance the comet could be lost in hazy or humid skies. And if there are clouds stretching across the horizon, that could be a deal-breaker. Finding out you’re clouded out at 3 a.m. is a truly rude awakening.

To determine if the forecast is favorable, click on over to Digital.Weather.gov, focus in on your viewing area and select “Sky Cover (%)” from the drop-down menu. Then move the slider bar to your planned viewing time (for example, “At Jul 11, 3 a.m.”) and check whether conditions are expected to be blue (set your alarm) or gray (sleep in).

Bring binoculars: Although NEOWISE is bright enough for naked-eye viewing, your naked eyes will see it pretty much as a fuzzy star. To make out the comet’s tail clearly, you’ll probably need to break out the binoculars or a telescope.

Skywatchers have been putting up some impressive pictures of NEOWISE and its double tail — a curving tail of cosmic dust illuminated by the sun, plus a dimmer, bluish tail of ions streaming straight out. You just have to remember that those photos are typically enhanced or stacked to bring out details you won’t be able to see with your own eyes.

Be realistic: Most celestial phenomena are subtler than the hype makes them out to be, so don’t get frustrated if that turns out to be the case for NEOWISE. While you’re out there comet-hunting, take a moment to check out other celestial wonders — ranging from the International Space Station and passing satellites to the moon, planets and meteors.

Even if you miss seeing NEOWISE with your naked eyes, you can still connect with the comet by checking out the views from the space station, NASA’s Parker Solar Probe and the scores of dedicated comet-hunters whose photos appear on SpaceWeather.com, EarthSky and other online galleries.

Update for 2 p.m. PT July 13: I discovered that 4 a.m. is really too late to look for the comet in northern-latitude locations (like Seattle). I totally missed seeing it at 4 a.m. on July 11 — but had much better luck at 3 a.m. on July 13, when it was still dark enough to spot NEOWISE in advance of the predawn glow. I’ve changed the time references in this story for the benefit of those still trying to catch sight of the comet before dawn.

By Alan Boyle

Mastermind of Cosmic Log, contributing editor at GeekWire, author of "The Case for Pluto: How a Little Planet Made a Big Difference," president of the Council for the Advancement of Science Writing. Check out "About Alan Boyle" for more fun facts.

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