C/2022 E3 (ZTF)
C/2022 E3 (ZTF) is a non-periodic comet from the Oort cloud that was discovered by the Zwicky Transient Facility (ZTF) on 2 March 2022. The comet has a bright green glow around its nucleus, due to the effect of sunlight on diatomic carbon and cyanogen. The comet's systematic designation starts with C to indicate that it is not a periodic comet, and "2022 E3" means that it was the third comet to be discovered in the first half of March 2022.
C/2022 E3 (ZTF) on 27 January 2023 | |
| Discovery | |
|---|---|
| Discovered by | Zwicky Transient Facility |
| Discovery date | 2 March 2022 |
| Orbital characteristics | |
| Observation arc | 456 days |
| Number of observations | 3382 |
| Orbit type | Long-period comet |
| Aphelion | ≈2800 AU (barycentric epoch 1950) |
| Perihelion | 1.112 AU |
| Eccentricity | 0.999988 (barycentric epoch 2050) |
| Orbital period | ≈50,000 yr (inbound) Possible Ejection (outbound) |
| Inclination | 109.17° |
| Last perihelion | 12 January 2023 |
| Earth MOID | 0.221 AU (33.1 million km) |
| Jupiter MOID | 1.743 AU (260.7 million km) |
| Physical characteristics | |
| Dimensions | ≈1 km |
| Comet total magnitude (M1) | 10.5±0.6 |
The comet nucleus was estimated to be about a kilometer in size, rotating every 8.5 to 8.7 hours. Its tails of dust and gas extended for millions of kilometers and, during January 2023, an anti-tail was also visible.
The comet reached its perihelion on 12 January 2023, at a distance of 1.11 AU (166 million km; 103 million mi), and the closest approach to Earth was on 1 February 2023, at a distance of 0.28 AU (42 million km; 26 million mi). The comet reached magnitude 5 and was visible with the naked eye under moonless dark skies.