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Rare comet may be visible to the naked eye. Here's where to look.

By
Terry Eliasen, Exec. Weather Producer
WBZ-TV Executive Weather Producer
Terry Eliasen is a meteorologist and executive producer of the WBZ-TV Weather Team. He has worked at WBZ for more than 20 years.
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Terry Eliasen, Exec. Weather Producer

/ CBS Boston

BOSTON - It isn't often that we get the chance to see a comet with the naked eye. But, in a year already filled with so many astronomical treats, it looks like we will be able to add a comet to the list.

Comet C/2023 A3 making closest pass to Earth

Comet Tsuchinshan-ATLAS has an 80,000 year orbit and, it just so happens, that it is now approaching its closest pass to Earth.  On Wednesday, the comet made its closest approach to our sun and on Saturday, October 12 at 11:39 a.m. it will be just 43,911,824 miles from Earth (its closest pass). At that time, the comet's tail will essentially be pointing right at Earth. However, in the days to follow, the tail will pivot eastward, making for dramatic changes in viewing from night to night.

The comet is massive in size and length. Its head currently measures a whopping two miles in diameter. The tail, which is largely comprised of tiny pieces of ice and dust, is believed to be as long as 18 million miles.

C/2023 A3 was briefly and barely visible last week in the early morning sky. In the end, most folks were unable to see it as it was very faint and low to the horizon.

TOPSHOT-URUGUAY-ASTRONOMY-COMET-TSUCHINSHAN-ATLAS
Comet C2023 A3 Tsuchinshan-Atlas is seen over the hills near the village of Aguas Blancas, Lavalleja Department, Uruguay, at dawn on September 28, 2024. MARIANA SUAREZ/AFP via Getty Images

What time is the comet visible tonight?

We will have a much better chance this time around. Starting on Friday night and lasting for several days, the comet will be visible in the western sky just after sunset.

On Friday it was very low on the horizon (about 4 degrees) and likely a bit tough to spot.

In the nights that follow, conditions should get better and better.

comet-graphic.jpg
WBZ-TV graphic CBS Boston

Peak viewing will occur between October 12-26. The comet will become the largest visible object in our solar system (after the moon, obviously).

On Saturday, the comet was about 6 degrees above the west-southwest horizon about 45 minutes after sunset. If you hold out your fist at an arm's length the comet will be about one half "fist" above the horizon. It will set about 45 minutes later.

Each successive night next week, the comet will be about 3 degrees higher in the sky and it will set about 16 minutes later.

By Saturday, October 19, the comet will have risen to about 30 degrees (3 fists) above the horizon and will set nearly three and a half hours later. It will lose some brightness each night though, slowly fading and getting harder and harder to see with the naked eye.

Forecast for watching the comet

Naturally, we will need the weather to cooperate in order for us to see anything on any given night. Sunday's clouds and showers should clear during the day Monday and allow for good viewing once again. There will be even better chances to observe the comet on Tuesday when there is more widespread clearing!

As always, we would love to see and share your pictures. Send them to weather@wbztv.com.

© 2024 CBS Broadcasting Inc. All Rights Reserved.

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