Our guide to viewing C/2023 A3 (Tsuchinshan–ATLAS)

Observing Comets with SkyTools Visual

SkyTools offers many unique features for observing comets not found in any other software. Comet observing is finally made easy because you will know what to expect in your telescope with your local conditions. 

Exclusive features not found in other software

  • Accurate Visual difficulty estimates from our legendary contrast model

  • Custom observing synopses

  • Unique daily optimum viewing time charts 

  • Magnitudes derived from recent observations

  • Coma diameters and tail lenghts derived from recent observations

Finding comets

Using the multi-view telescope (or binocular) finder charts, even beginners can easily find naked-eye, telescopic, or binocular comets. These simulations display what you’ll see through your eyepiece, adjusted for your location, instrument, light pollution, and experience. Click the thumbnail for a plot of comet C/2023 A3 (Tsuchinshan–ATLAS) as seen to the unaided eye. The comet is plotted nightly at optimal viewing. Each night shown is a night when it will be easily visible to the unaided eye in October. From SkyTools, simply export your own chart to your phone as an image, or print it out, and observe at the indicated time each night.

Time wasted on fickle comets

SkyTools stays current, unlike other software and apps that require you to jump through hoops to load what you hope is the latest comet data, often showing bright comets long after they’ve disintegrated. Other software and websites rely on outdated Minor Planet Center data for magnitudes, while SkyTools integrates recent observations made by amateur astronomers to also provide accurate sizes and brightness in its online database, which is updated automatically. People say comets are fickle, and they are up to a point, but at Skyhound we have shown again and again that it is primarily the simplistic predictions made elsewhere that are fickle. Our predictions use a cutting-edge model that even NASA doesn't have access to. 

Is that comet visible in my telescope?

Big diffuse comets are harder to detect than small compact ones, even with an accurate magnitude. SkyTools’ contrast algorithm removes the guesswork, predicting visibility under your specific conditions and showing the comet’s size for easier identification in the eyepiece.

When and where should I look?

SkyTools excels at planning. Find the best nights to observe, ideal times, and create custom finder charts, or control your scope directly. This isn’t a generic calculation—SkyTools factors in your light pollution, telescope, and the comet’s coma size and concentration for accurate predictions. 

Custom observing synopses

SkyTools can tell you, in words, everything you need to know about an upcoming comet:

On October 12, C/2023 A3 (Tsuchinshan-ATLAS) is best visible to the unaided eye between 07:15p and 07:39p, with the optimum view at 07:29p. Look for it in Virgo, very low in the western sky during evening twilight. It is easy visually to the Naked Eye. It is magnitude 0 with a diameter of 7.3 arc minutes. 

In the following 30 days this object is easy visually on October 13-18, and again from October 20, with the best view coming on October 13. During this period it will fade rapidly and will reach peak altitude of 36° on November 6.

C/2023 A3 (Tsuchinshan-ATLAS) is past perihelion, which occurred in late September 2024. On September 27 this comet will pass within 0.5 AU of the earth.

Note: the above predictions are customized for a specific location. 

Logging your observations

SkyTools’ logbook is perfect for recording your observations of comets or anything else in the sky. Use the Night Log to capture the entire experience, like when raccoons almost made you drop your Nagler!

SkyTools Visual is for Windows and starts at $99 USD.