Catch the Comet Before It's Gone!

Photo by Paul Mason 7-22-2010 The brightest comet to appear in Northern Hemisphere skies in nearly a quarter of a century is ending its run in our sky, and you’ll never see it again. So go outside before the end of the month and try to see the Comet NEOWISE before it’s gone.

Comet NEOWISE was discovered on March 27 by astronomers during the NEWVISE mission, which used NASA’s Wide-field Infrared Survey Explorer (WISE) space telescope to look for near-Earth objects like asteroids and comets.

Joseph Masiero, NEOWISE deputy principal investigator at NASA’s Jet Propulsion Laboratory says that from its infrared signature, we can tell the comet’s nucleus is about 3 miles across (5  km) across, and is covered with sooty, dark particles left over from its formation near the birth of our solar system 4.6 billion years ago.
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Is NEOWISE a great comet? There’s no strict definition for great comet, but most agree that Hale-Bopp—widely seen by people in 1997—was one. NEOWISE is nowhere as bright as Hale-Bopp, which was clearly visible to the naked eye, but it’s absolutely the best comet we’ve had for casual observers in some time. 
This image is from Bob King – aka AstroBob – in Duluth, Minnesota. He wrote: “My first view of Comet NEOWISE at dusk instead of dawn from a lake near Duluth on July 11. Comets and water naturally go together as they’re thought responsible in part for delivering water to the early Earth.” Thank you, Bob!


​The comet made its closest approach to the sun (called perihelion) on July 3. At the time, it swept to within 29.4 million miles of the sun, or inside the orbit of Mercury, the innermost planet. Unlike some comets, it survived the close encounter with our star. And, although it was moving steadily away from the sun, it was steadily approaching Earth. The comet blossomed, and has been putting on a formidable show widely seen by binocular observers and astophotographers for the last month.

On July 2, NOEWISE passed as close to the Earth as it will come (called perigee), 64.3 million miles away. Because it had been approaching the Earth during the last few weeks, it has been fading very slowly. At one point, it shown at around magnitude +2 (about as bright as Polaris, the North Star). 
ou haven’t yet had a chance to check out Comet Neowise for yourself, you’ll want to get a look at it sooner rather than later, as the comet has been dimming over the last few days.. The comet’s proximity to the Big Dipper will help you locate it. Just remember that your clenched fist held at arm’s length measures roughly ten degrees. About 2 hours after sunset, face northwest to find the Big Dipper. Go approximately 15 degrees (about 1 ½ fists) down and to the lower left of the bottom of the “bowl” of the Big Dipper, and ultimately you will arrive in the vicinity of the comet. If you’re located in a dark location, free of bright lights, you should be able to make out the comet as a pale streak of light with your naked eye. Then train your binoculars on the area for a better look.

After Monday, the moon will reach its first quarter (half) phase, and in the nights thereafter, it will be a waxing gibbous moon, flooding the late night and early morning sky with its own light.

Because of its extremely long, elliptical orbit, the Comet NEOWISE won’t be back for another 6,800 years, NASA has said.

If the comet has whetted your appetite for other astrological and space events, here’s what’s coming up:

July 30 – NASA’s Mars 2020 rover launches to the Red Planet. Lift off is on a United Launch Alliance Atlas V rocket from Cape Canaveral Air Force Station in Florida. You can watch it live.
August 11-12 – The Perseid meteor shower peaks.

Until next week, good reading and be safe.