Is the Comet Atlas worth seeing? Expert explains why you should “enjoy the opportunity.”

BOSTON – The massive comet this is starting to happen visible in the night sky in the United States will not last too long. And once it's gone, Comet Tsuchinshan Atlas will no longer be visible to the naked eye from Earth for the next 80,000 years.

To see it, you'll need a clear view of the western horizon from just after sunset until about October 24, according to NASA. So is it worth going outside during dinner and catching a glimpse of this heavenly visitor?

Space weather expert Shawn Dahl says, “People should enjoy the opportunity to see something so rare.” He said he could easily see the giant comet from his vantage point in Wyoming on Monday.

“It’s very spectacular,” said the Space Weather Prediction Center forecaster.

Comet Atlas has a huge tail – and an opposite tail

One thing viewers will immediately notice is the comet's tail of ice and dust, which is believed to be up to 18 million miles long.

“The tail is huge,” Dahl told Terry Eliasen, executive weather producer for CBS Boston. “It is created by the solar wind and interaction with the sun.”

Comet Atlas has even developed a countertail, which Dahl says appears to be a small, thin line in front of the comet, but is not what it appears to be.

“This tail is kind of pointing toward the sun, but it's really an optical illusion,” he said. “It’s just a change in perspective from Earth.”

Where did the comet come from?

Dahl said Comet Atlas “has been on a long journey.”

“It came from the outer reaches of our solar system, about one to two light years away,” Dahl said. “It’s a very long period comet.”

According to NASA, the comet formed in the Oort cloud, which lies far beyond Pluto and is believed to contain billions or trillions of pieces of space junk.

How can you see the comet?

The best time to view is about 45 minutes after sunset. Dahl recommends looking for an area above and to the right of Venus, the brightest “star-like” object in the evening sky.

You can bring binoculars, but they are not required.

“You just have to be patient and eventually it will reach a level that will be visible to the naked eye soon after dark,” he said.

The incredibly rare comet sighting, the total Solar eclipse from April and last week breathtaking Northern lights show making this one of the best years for skygazing that Dahl can remember.

“Everything lined up like this is just fantastic because it really raises awareness of the beauty of space and our interactions with elements in our solar system, but also space weather and how important it actually is,” he said.