Also known as comet A3 and C/2023 A3, this snowball from the depths of the solar system has a central coma 130,000 miles (209,000 kilometers) in diameter.
It also has a trademark tail extending 18 million miles (29 million kilometers).
Tonight it will be 79 million miles (127 million kilometers) from the sun and 78 million miles (125 million kilometers) from Earth.
As a bonus, it’s now visible in a dark sky, with last week’s supermoon no longer bleaching the night sky.
Check my feed every day this week and next for a daily “comet tracker” with sky charts and tips for viewing the comet.
Does the comet remain visible? Comet Tsuchinshan-ATLAS is no longer visible to the unaided eye, but it is still worth locating if you have binoculars or a small telescope.
It is believed by astronomers to orbit the sun once every 80,000 years. It is a long-period comet from the Oort Cloud, a sphere that contains millions of comets.
The snowball from the solar system’s depths, also referred to as comet A3 and C/2023 A3, has a central coma that is 130,000 miles (209,000 kilometers) in diameter. At 18 million miles (29 million kilometers), it also boasts a distinctive tail.
This comet is technically visible to the unaided eye due to its magnitude of +3.4, but as it approaches the Oort Cloud, it is rapidly becoming smaller and fainter. 78 million miles (125 million kilometers) will separate it from Earth and 79 million miles (127 million kilometers) from the sun tonight.
But if you know where to look and when to look, it’s still in the Ophiuchus constellation. Also, because last week’s supermoon stopped bleaching the night sky, it can now be seen in a dark sky. Here’s how to use a camera or smartphone to take a picture of the comet.
Note: the viewing schedule and instructions are intended for viewers in the Northern Hemisphere’s mid-latitudes. Consult Stellarium Web to find the precise time of sunset where you are and the comet’s setting times.
Comet Tsuchinshan-ATLAS Location: Sunday, Oct. 27.
Location: Ophiuchus, west, 54 degrees from the sun.
Time: approximately 22:15 local time, or 60 minutes after sunset where you are.
Magnitude: +3 points 4.
There are 79 million miles (127 million kilometers) between the comet and the sun.
Earth is 78 million miles (125 million kilometers) away from the comet.
Thus far, the bright planet Venus and the bright red star Arcturus have served as the comet’s beacons. However, both are so near the horizon an hour after sunset that they are unlikely to be seen as October comes to an end. To locate the comet, instead, use the Summer Triangle’s stars. Finding the Vega in the constellation Lyra and Deneb in Cygnus above due west should be fairly simple.
The Summer Triangle: How to Locate the Comet.
Altair in Aquila can be seen to the left of both. Draw a rough triangle with Altair, Vega, and the horizon at the third point, which is approximately where the comet will be. To see it, you will need binoculars and a clear, dark sky.
How to use Vega to find the comet.
On the left, draw a coat-hangar shape; the comet will be the hook to the side. Draw an imaginary line from Vega straight to the horizon. Until you locate it, use binoculars to scan.
This week and the following, check my feed daily for a “comet tracker” that includes sky charts and comet viewing tips.
I hope you have big eyes and clear skies.
