The bright Comet C/2020 F3 (NEOWISE), which has garnered the attention of skywatchers around the world in recent weeks, will make its closest approach to Earth tonight (July 22).
At approximately 9:09 p.m. EDT (0109 GMT on July 23), Comet NEOWISE will reach perigee, or its closest distance to Earth. At that time, the comet will be 0.69 AU (astronomical units, or the average Earth-sun distance) away from Earth, according to NASA's orbit calculator. That's about 64.3 million miles, or 103.5 million kilometers. Shining with a magnitude of 2.2, the comet is currently about as bright as Polaris, the North Star, and can be observed in dark skies without the aid of a telescope or binoculars.
Skywatchers in the Northern Hemisphere will be able to spot the comet after sunset; it will be in the constellation of Ursa Major, just below the Big Dipper. And if you're unable to catch the naked-eye comet in the night sky during its close approach this evening, you'll have another chance to see the space rock in two live webcasts on Thursday (July 23).
First, astrophysicist Gianluca Masi of The Virtual Telescope Project in Italy will stream live telescope views of the comet starting at 3 p.m. EDT (1900 GMT). You can watch it live here on Space.com, courtesy of The Virtual Telescope Project, or you can watch it on YouTube.
Later on Thursday, the Lowell Observatory in Flagstaff, Arizona will stream more live views of Comet NEOWISE in a webcast beginning at 11:30 p.m. EDT (0330 GMT on July 24). Hosted by Lowell Observatory director Jeff Hall and senior astronomer Dave Schleicher, the live discussion "will highlight the scientific importance of this 'dirty iceball' and how to view it," the observatory said in a statement. The Lowell Observatory's webcast will also stream live on Space.com, and on YouTube.
If you 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 slightly over the past few days. As it slowly fades from view, the naked-eye comet will soon require telescopes or binoculars to be seen and, after it disappears, it won't be back again in our lifetime. Because of its extremely long, elliptical orbit, the comet won't be back for another 6,800 years, NASA has said.
Comet NEOWISE is currently on the outbound leg of its trip through the solar system, having swooped around the sun on July 3. At its farthest distance from the sun, called aphelion, the comet will be about 715 AU (66 billion miles, or 107 billion km) away.
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