C/2023 A3 (Tsuchinshan–ATLAS)
< C
Comet Tsuchinshan-ATLAS photographed from Ohio, USA on 17 October 2024 | |
| Discovery | |
|---|---|
| Discovery site | Purple Mountain Obs. ATLAS–SAAO (M22) |
| Discovery date | 9 January 2023 |
| Designations | |
| C/2023 A3 | |
| A10SVYR | |
| Orbital characteristics | |
| Epoch | 10 February 2024 (JD 2460350.5) |
| Observation arc | 2.86 years (1,045 days) |
| Earliest precovery date | 9 April 2022 |
| Number of observations | 5,710 |
| Aphelion | ≈380,000 AU (inbound) |
| Perihelion | 0.391 AU |
| Semi-major axis | ≈190,000 AU (inbound) |
| Eccentricity | 0.9999797 (inbound) 1.0000353 (outbound) |
| Orbital period | ≈83 million years (inbound) Ejection trajectory (outbound) |
| Max. orbital speed | 67.33 km/s |
| Inclination | 139.1° |
| 21.56° | |
| Argument of periapsis | 308.5° |
| Last perihelion | 27 September 2024 |
| TJupiter | –0.583 |
| Earth MOID | 0.275 AU |
| Jupiter MOID | 1.096 AU |
| Physical characteristics | |
Mean radius | <5.9 ± 0.2 km (3.67 ± 0.12 mi) |
| 0.04 (assumed) | |
| Comet total magnitude (M1) | 6.5 |
| Comet nuclear magnitude (M2) | 9.2 ± 0.3 |
| –4.9 (2024 perihelion) | |
Comet Tsuchinshan–ATLAS, also known as the Great Comet of 2024 and formally designated as C/2023 A3, is a comet from the Oort cloud discovered by the Purple Mountain Observatory in China on 9 January 2023 and independently found by ATLAS South Africa on 22 February 2023. The comet passed perihelion at a distance of 0.39 AU (58 million km; 36 million mi) on 27 September 2024, when it became visible to the naked eye. Tsuchinshan–ATLAS peaked its brightest magnitude on 9 October, shortly after passing the Sun, with a magnitude of −4.9 per reported observations at the Comet Observation Database (COBS).