Rare comet streaking across the night sky. Here's how to watch it: NPR

Comet C/2023 A3 Tsuchinshan Atlas is seen at dawn on September 28 over the hills near the village of Aguas Blancas in the Lavalleja department of Uruguay.

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A comet discovered last year – known as C/2023 A3 Tsuchinshan-ATLAS – will approach Earth in the coming days.

The snow-covered dirtball is nearly 2 miles across and its tail of dust and gases stretches for tens of millions of miles, Bill Cooke, head of NASA's Meteoroid Environment Office at the Marshall Space Flight Center in Huntsville, Alabama, told NPR.

It was first discovered in 2023 by observers at the Purple Mountain Observatory in China Final alarm system for an asteroid impact on Earth (ATLAS) telescope in South Africa. Of the Oort CloudA spherical shell that surrounds the solar system and contains icy objects such as comets, the comet will come within 44 million miles of Earth, NASA said.

How can I see it?

The comet will appear low on the western horizon in the twilight glow starting Saturday, Oct. 12, through the end of the month, initially about 45 minutes after sunset, Cooke said.

The comet can be seen without special equipment, but the best view is through binoculars.

“Comets look pretty good to the naked eye, but with binoculars they will blow your mind,” Cooke said. “It will be really good in binoculars. So if you have binoculars, why not bring them and take a look at the comet?”

Over the course of the month, the comet will get higher in the sky each night as it moves further from the sun and out of the solar system – and it will appear dimmer and harder to see with the naked eye. The comet will fade either in the week before Halloween or around Halloween, depending on how bright it is, Cooke also said. The comet can then be observed for a few months – albeit with a professional telescope.

If I miss it, when can I see it again?

Unfortunately, it probably won't happen to you. According to NASA, the comet is not expected to fly by again for 80,000 years after the end of the month.

And it is currently not expected that another comet will be visible in the near future.

“Bright comets are very rare and are usually newcomers to the inner solar system,” Cooke said.