Comet C/2023 A3 Tsuchinshan-Atlas can be seen at sunrise on September 28 over the hills near the village of Aguas Blancas, Lavalleja department, Uruguay.

Mariana Suarez/Getty Images

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Mariana Suarez/Getty Images

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

The snowy dirt ball is nearly 2 miles (3.2 km) in diameter and its tail of dust and gases extends for tens of millions of miles, Bill Cooke, chief 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 and a Asteroid Terrestrial impact Final warning system (ATLAS) telescope in South Africa. From the Oort clouda spherical shell surrounding the solar system and containing icy objects such as comets, the comet will come within 45 million miles of Earth, NASA said.

How can I see it?

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

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

“Comets look good to the naked eye, but binoculars will knock your socks off,” Cooke said. ‘It will be really good with binoculars. So if you have binoculars, take them with you and take a look at the comet.”

As the month progresses, the comet will rise higher in the sky each night as it moves further from the sun and out of the solar system – appearing fainter and becoming harder to see with just the eyes. The comet will fade either the week before Halloween or around Halloween, depending on how bright it is, Cooke also said. The comet can then be seen for a few more months – but then with a professional telescope.

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

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

And right now, no other comet is expected to be visible in the near future.

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