Comet C/2023 A3 (Tsuchinshan-ATLAS) was discovered by the Asteroid Terrestrial-impact Last Alert System (ATLAS) on 22 February 2023 and it was also independently observed few weeks before in January 2023 at the Tsuchinshan Chinese Observatory (Purple Mountain Observatory of the Chinese Academy of Sciences). The official designation includes both Tsuchinshan and ATLAS due to these independent observations. Its retrograde orbit, meaning it moves in the opposite direction to most major solar system objects, is parabolic-like with a perihelion distance of 0.39 astronomical units (AU). Comet C/2023 A3 (Tsuchinshan-ATLAS) is notable and actively observed because, based on current estimations, it is could become bright enough to be visible to the naked eye during its perihelion passage between September and October 2024.
Comet C/2023 A3 (Tsuchinshan-ATLAS) Position Calculator
Compute the position of Comet C/2023 A3 (Tsuchinshan-ATLAS) for any date and time between 1 January 2000 and 31 December 2099 and visualize the results on an interactive sky map.
In Evidence
Comet C/2023 A3 (Tsuchinshan-ATLAS)
Comet C/2023 A3 (Tsuchinshan-ATLAS) is in the constellation of
Vulpecula,
at a distance of
Finder Charts
View interactive star map
High precision deep sky finder chart, 60 arcmin wide, showing where Comet C/2023 A3 (Tsuchinshan-ATLAS) is right now. Click on the image to see a more detailed fullscreen tracker view.
Also check out Where is Comet C/2023 A3 (Tsuchinshan-ATLAS)?, a page that provides all the information needed to find Comet C/2023 A3 (Tsuchinshan-ATLAS) in the sky and additional links to sky charts.
Celestial Coordinates
Apparent
J2000
Additional Information
The observed values of Magnitude, Coma Diameter and Tail Length are derived from the most recent observation recorded at the Comet Observers Database. The value of Predicted Magnitude comes from the JPL Horizons ephemerides service and, in the case of comets, might be inaccurate given the highly dynamic and unpredictable behavior of these objects. When available, please refer to the Observed Magnitude value and consider the Predicted Magnitude as a directional indication. We acknowledge with thanks the comet observations from the COBS Comet Observation Database contributed by observers worldwide and used in this table to report recent comet observations.
Rise and Set Times
Today's rise, transit and set times of Comet C/2023 A3 (Tsuchinshan-ATLAS) from Greenwich, UK (all times relative to the local timezone Europe/London):
- C/2023 A3 (Tsuchinshan-ATLAS) is below the horizon from Greenwich, UK.
- Given its current magnitude, C/2023 A3 (Tsuchinshan-ATLAS) is visible with the help of a telescope having an aperture of 6 inches (150mm) or more.
- Go to interactive sky chart
If you need to access this information frequently for your observations, you can create a simple customized Quick Access page, so that you can easily bookmark it in your browser favorites or add a shortcut to your mobile phones' home screen.
Distance from Earth
The distance of Comet C/2023 A3 (Tsuchinshan-ATLAS) from Earth is currently
The following chart shows the distance of Comet C/2023 A3 (Tsuchinshan-ATLAS) from Earth as a function of time. In the chart the distance data is measured in Astronomical Units and sampled with an interval of 1 day.
The value of the reported distance might be somewhat inaccurate around the times of closest approach for objects passing extremely close to Earth. The value of the distance of C/2023 A3 (Tsuchinshan-ATLAS) from Earth is also available as a real time updated value in the Live Position and Data Tracker.
Closest Approach
Between 1 January 2000 and 31 December 2099, the closest approach of Comet C/2023 A3 (Tsuchinshan-ATLAS) to Earth happens on Sun Oct 13 2024 at a distance of 0.472744 Astronomical Units, or 70,721,499 kilometers:
NOTE: values for the closest approach are computed with a sampling interval of 1 day.
Light Curve
The following chart is the predicted light curve (visual magnitude as a function of time) of Comet C/2023 A3 (Tsuchinshan-ATLAS), according to the most recent ephemerides data. Magnitude data is sampled with a 2 days interval and there might be inaccuracies for objects changing brightness very rapidly during the course of a few days. For comets there could be large discrepancies between the observed and predicted brightness because of their highly dynamic behaviour.
Orbital Elements
The following table lists the orbital elements of Comet C/2023 A3 (Tsuchinshan-ATLAS) at epoch 24 January 2024 00:00 UTC (JD: 2460334.5). Source: JPL Small-Body Database
| Element | Symbol | Value |
|---|---|---|
| Orbit eccentricity | e | 1.00012475 |
| Orbit inclination | i | 139.11502467° |
| Perihelion distance | q | 0.39145906 AU 58,561,442 km |
| Aphelion distance | Q | n.a. |
| Semi-major axis | a | n.a. |
| Orbital period | period | n.a. |
| Date of perihelion transit | Tp | 2024-Sep-27 17:38:45 2,460,581.2353 JD |
| Argument of perihelion | peri | 308.4872848828° |
| Longitude of the ascending node | node | 21.558609111275° |
| Mean anomaly | M | -0.0013834563352416° |
| Mean motion | n | 0.00000561°/day |
View Comet C/2023 A3 (Tsuchinshan-ATLAS) in the 3D Solar System Simulator
15 Days Ephemeris
The following table lists the ephemerides of Comet C/2023 A3 (Tsuchinshan-ATLAS) computed for the past and next 7 days, with a 24 hours interval. Apparent celestial coordinates are provided.
| Date | Right AscensionR.A. | DeclinationDec. | MagnitudeMag | Constellation |
|---|---|---|---|---|
| 2025 May 11 | 20h 07m 21s | +25° 35’ 28” | 14.32 | Vulpecula |
| 2025 May 12 | 20h 06m 25s | +25° 44’ 27” | 14.32 | Vulpecula |
| 2025 May 13 | 20h 05m 28s | +25° 53’ 18” | 14.33 | Vulpecula |
| 2025 May 14 | 20h 04m 28s | +26° 02’ 01” | 14.33 | Vulpecula |
| 2025 May 15 | 20h 03m 28s | +26° 10’ 36” | 14.34 | Vulpecula |
| 2025 May 16 | 20h 02m 27s | +26° 19’ 02” | 14.34 | Vulpecula |
| 2025 May 17 | 20h 01m 24s | +26° 27’ 19” | 14.35 | Vulpecula |
| 2025 May 18 | 20h 00m 21s | +26° 35’ 27” | 14.36 | Vulpecula |
| 2025 May 19 | 19h 59m 15s | +26° 43’ 26” | 14.36 | Vulpecula |
| 2025 May 20 | 19h 58m 09s | +26° 51’ 14” | 14.37 | Vulpecula |
| 2025 May 21 | 19h 57m 02s | +26° 58’ 53” | 14.37 | Vulpecula |
| 2025 May 22 | 19h 55m 52s | +27° 06’ 21” | 14.38 | Vulpecula |
| 2025 May 23 | 19h 54m 42s | +27° 13’ 37” | 14.39 | Vulpecula |
| 2025 May 24 | 19h 53m 31s | +27° 20’ 43” | 14.39 | Vulpecula |
Additional Resources on TheSkyLive
- Comet C/2023 A3 (Tsuchinshan-ATLAS): Complete reference information on TheSkyLive.com
- Where is Comet C/2023 A3 (Tsuchinshan-ATLAS)?: Key information on locating Comet C/2023 A3 (Tsuchinshan-ATLAS) in the sky.
- Distance from Earth: Find out how far Comet C/2023 A3 (Tsuchinshan-ATLAS) is from Earth right now.
- How Bright is Comet C/2023 A3 (Tsuchinshan-ATLAS)?: Current visual brightness (magnitude) and apparent size.
- Rise and Set Times: Comet C/2023 A3 (Tsuchinshan-ATLAS)'s rise and set times from your location.
- Interactive Sky Map: planetarium-style interactive visualization of Comet C/2023 A3 (Tsuchinshan-ATLAS)'s position in the sky.
- Live Position Tracker: high precision position tracker with deep space imagery.
- Ephemeris: 15 days Comet C/2023 A3 (Tsuchinshan-ATLAS)'s computed ephemeris.
- Orbital elements: information about Comet C/2023 A3 (Tsuchinshan-ATLAS) orbital parameters.
- Orbit Visualization. 3d interactive visualization showing the orbit of Comet C/2023 A3 (Tsuchinshan-ATLAS) with respect to the major Solar System objects.