C/2020 T2 (Palomar) is a non-periodic comet with an approximately 5,530-year orbital period around the Sun. It was discovered from the Palomar Observatory on 7 October 2020.[1]
 The comet images by ZTF on 12 May 2021 | |
| Discovery[1] | |
|---|---|
| Discovered by | D. A. Duev |
| Discovery site | Palomar Observatory |
| Discovery date | 7 October 2020 |
| Designations | |
| CK20T020 | |
| Orbital characteristics[2] | |
| Epoch | 15 May 2021 (JD 2459349.5) |
| Observation arc | 1,015 days (2.78 years) |
| Earliest precovery date | 11 December 2019 |
| Number of observations | 2,755 |
| Aphelion | ~620 AU |
| Perihelion | 2.05 AU |
| Semi-major axis | ~310 AU |
| Eccentricity | 0.99343 |
| Orbital period | ~5,530 years |
| Inclination | 27.873° |
| 83.048° | |
| Argument of periapsis | 150.38° |
| Mean anomaly | 359.98° |
| Last perihelion | 11 July 2021 |
| Next perihelion | ~7550s |
| TJupiter | 1.585 |
| Earth MOID | 1.081 AU |
| Jupiter MOID | 1.786 AU |
| Physical characteristics[3] | |
Mean diameter | 11.05 ± 0.1 km (6.866 ± 0.062 mi) |
| Comet total magnitude (M1) | 9.5 |
| Comet nuclear magnitude (M2) | 12.2 |
Observational history
editThe comet was first identified by D. A. Duev when he analyzed the photographic plates taken by the Palomar Observatory on 7 October 2020, where he spotted a tail stretching about 5 arcseconds in length.[1]
Its large perihelion distance of 2.05 AU (307 million km) has enabled numerous follow-up observations to be conducted until 2022.[2] On 10 January 2021, the comet was 2.59 AU (387 million km; 241 million mi) from Earth, and around magnitude 16.4 in brightness. Between 22 January and 5 July 2021, extensive observations from the Purple Mountain Observatory detected traces of hydrogen cyanide (HCN) gas continuously emanating from its coma.[4] On 17 May 2021, the comet was located as a 10.5-magnitude object with an outer green coma measuring 10-arcminutes in size near the Messier 3 globular cluster.[5][6] Around two weeks before perihelion, observations of the comet noted that it lacked a significant dust tail, but there was a strong condensation on its coma, reminiscent of a typical Manx comet,[7] where near-infrared spectropolarimetry measurements of the comet were also conducted in the same time period.[8] Post-perihelion observations from the Hissar Observatory between 27 August and 2 September 2021 revealed that the upper estimate of the size of its nucleus is roughly 11.05±0.1 km in diameter.[3] By October 2021, the comet faded back to an 11th-magnitude object as it moved away from both the Sun and the Earth.[9]
References
edit- ^ a b c "MPEC 2020-U170: Comet C/2020 T2 (Palomar)". www.minorplanetcenter.net. Minor Planet Center. 22 October 2020. Retrieved 3 February 2025.
- ^ a b "C/2020 T2 (Palomar) – JPL Small-Body Database Lookup". ssd.jpl.nasa.gov. Jet Propulsion Laboratory. Retrieved 3 February 2025.
- ^ a b G. I. Kokhirova; A. M. Buriev; N. T. Sharipova; S. N. Safarov (11–15 March 2024). Long-Period Comet C/2020 T2 (Palomar) and Its Characteristics Based on Observations at the Hissar Astronomical Observatory (PDF). 55th Lunar and Planetary Science Conference. Vol. 3040. The Woodlands, Texas, USA. Bibcode:2024LPICo3040.1803K.
- ^ Z. Wang (2025). "Observations of the 3.4 mm line of HCN in C/2020 T2 (Palomar)" (PDF). Monthly Notices of the Royal Astronomical Society. 536 (3): 2496–2506. doi:10.1093/mnras/stae2685.
- ^ P. Chambó (9 June 2021). "Comet C/2020 T2 (Palomar) and Messier 3". Sky & Telescope. Retrieved 3 February 2021.
- ^ L. Kočmaroš (20 May 2021). "Kometa C/2020 T2 (Palomar)". Astronomiski Magazine (in Bosnian). Retrieved 3 February 2025.
- ^ Y. G. Kwon; J. R. Masiero; J. Markkanen (2022). "Examining the dust of the tailless Oort-cloud comet C/2020 T2" (PDF). Astronomy and Astrophysics. 668: A97. arXiv:2210.13091. doi:10.1051/0004-6361/202244853.
- ^ Y. G. Kwon; J. R. Masiero; J. Markkanen (18–23 September 2022). Near-infrared spectropolarimetry of Oort-cloud comet C/2020 T2 (Palomar): Can polarimetry reflect any gradients in the Oort cloud?. 16th Europlanet Science Congress. Granada, Spain. Bibcode:2022EPSC...16..190K. doi:10.5194/epsc2022-190. EPSC 2022-190.
- ^ M. Olason (9 October 2021). "Comet C/2020 T2 (Palomar)". Sky & Telescope. Retrieved 3 February 2021.
External links
edit- C/2020 T2 at the JPL Small-Body Database