If you’re wondering how to locate Comet Tsuchinshan-ATLAS tonight, here’s everything you need to know.

The best naked-eye comet since Comet NEOWISE – also known as the ‘lockdown comet’ because it appeared in July 2020 during the Covid pandemic – Comet Tsuchinshan-ATLAS (also called C/2023 A3 and Comet A3) is currently visible into the night sky immediately after sunset.

Tonight, Tuesday, October 15, is the second of the two best chances to see the comet at its brightest and best from the Northern Hemisphere. Considering it won’t return for about 80,000 years, it’s definitely worth a look.

Where is Comet Tsuchinshan-ATLAS?

Comet Tsuchinshan-ATLAS left the sun’s glare late last week and is now quite favorably positioned for a post-sunset view. On Saturday it came within 45 million miles (71 million kilometers) of its closest approach to Earth, but it was difficult to see because it was so close to the sun.

Tonight the comet will be at a huge 30 degree angle from the sun, meaning it will be relatively easy to see – if the sky is clear – and quite high in a dark sky.

However, you need a good, clear view of the western horizon to see it after sunset. The lower you can look to the horizon, the longer your view of Comet Tsuchinshan-ATLAS. If you find it, here’s how to photograph it.

Here you can read exactly when and where to look to see the comet with your naked eyes on Tuesday, October 15.

How to locate Comet Tsuchinshan-ATLAS: Tuesday, October 15

Position: west, 30 degrees from the sun in Serpens

Time: 45 minutes afterwards sunset where you are

Magnitude: +0.9

Comet’s distance from the Sun: 57.4 million miles (92.4 million kilometers)

Comet’s distance from Earth: 46.4 million miles (74.7 million kilometers)

Tonight the comet will be visible near the western horizon about 45 minutes after sunset, amid waning twilight, and set about an hour and 40 minutes later. That means it will be in the sky about 20 minutes longer than on Monday.

One thing to note is that the waxing moon will be bright, 97% illuminated, making the night sky less than dark. However, that shouldn’t have too much of an impact on comet spotting, as the moon will be shining in the south and the comet will be low in the west.

ForbesYour ultimate guide to seeing the comet every evening this week – before it fadesBy means of Jamie Carter

In clear skies you can use a planet and a star to locate the comet. Find the bright planet Venus and the bright star Arcturus; the comet will be just above halfway along an imaginary line between them. According to Sky & Telescope, the comet will be about two fists to the upper right of Venus (if viewed from the northern US) or right of Venus (if viewed from the southern US). “As twilight turns to night, the comet will remain in view, with its long, straight tail pointing upwards from the horizon,” he adds.

Tonight sees the comet move from the constellation Virgo to Serpens, a small and indistinct shape of eight stars that resemble a snake. Next to Serpens is Ophiuchus, ‘the snake merchant’, where the comet will move on Saturday, October 19.

How Comet Tsuchinshan-ATLAS will be seen tonight with a globular cluster and another comet

All you need to see the comet are your naked eyes, but any binoculars will give you an incredible view.

However, if you have a telescope, he says there is a bonus view available BBC Sky At Night magazine.

Viewed after sunset, Comet Tsuchinshan-ATLAS will be just 1.4 degrees (the width of your pink finger at arm’s length) below the M5 globular cluster in the constellation Serpens. Remarkably, comet 13P/Olbers will also be visible.

However, that mass of 13 billion year old stars and the second distant comet will not be visible to the naked eye. If you want to see these two objects, as well as Comet Tsuchinshan-ATLAS, through a huge telescope, tune in to a livestream from The Virtual Telescope from Italy at 5:00 PM UTC (1:00 PM EDT).

How bright is Comet Tsuchinshan-ATLAS?

The comet shines around magnitude +1, but changes every night. “Last Wednesday it passed its brightest point at a distance of 4 degrees from the Sun, with its head about as bright as Venus at magnitude -4, albeit with that light spread over an area of ​​the sky almost as large like the moon,” says astronomer Dr. Qicheng Zhang of Lowell Observatory in Flagstaff, Arizona, who has been monitoring the comet, said in an email. “That made it very difficult to see, even though it was the brightest comet in more than a decade. It is fading now, but also becomes much more visible and visually prominent in the evening as it moves away from the sun.”

When was Comet Tsuchinshan-ATLAS discovered?

Comet Tsuchinshan-ATLAS, discovered in January 2023 by astronomers at China’s Tsuchinshan (Purple Mountain) Observatory and the following month by the South African Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope, is a long-period comet from the Oort Cloud, a sphere around our solar system, which is home to millions of comets. It enters the inner solar system and orbits the sun once every 80,000 years.

Check my feed every day this week and next for a daily “comet tracker” with sky maps and comet viewing tips.

I wish you clear skies and big eyes.