Discovery | |
---|---|
Discovered by | Pan-STARRS |
Discovery date | 2 October 2017 |
Orbital characteristics | |
Epoch | 2458756.5 (30 Sept 2019) |
Observation arc | 3.93 years |
Number of observations | 6896 |
Orbit type | Oort cloud |
Aphelion | ~74000
AU (inbound)
[1] ~3000 AU (outbound) |
Perihelion | 1.6150 AU |
Eccentricity | 0.99971 |
Orbital period | ~7 million years (inbound)
[1] ~55000 years (outbound) |
Inclination | 57.232° |
Last perihelion | 4 May 2020 [2] |
Earth MOID | 1.2 AU (180 million km; 470 LD) |
Jupiter MOID | 0.99 AU (148 million km; 390 LD) |
C/2017 T2 (PanSTARRS) is an Oort cloud comet discovered on 2 October 2017 [3] when it was 9.2 AU (1.38 billion km) from the Sun. The closest approach to Earth was on 28 December 2019 at a distance of 1.52 AU (227 million km). It came to perihelion (closest approach to the Sun) on 4 May 2020 [2] when it was safe from disintegration at 1.6 AU from the Sun. ( Mars is also roughly 1.6 AU from the Sun.)
Comet C/2017 T2 (PanSTARRS) brightened to apparent magnitude 8 and was visible with 50mm binoculars. [4] [5] On 22-24 May 2020, the comet passed near the galaxy pair of Messier 81 and Messier 82, passing less than one degree from the latter. [6] In early June 2020 the comet was near the magnitude 1.8 star Dubhe in Ursa Major. [7]
Based on the light curve of the comet nucleus, it has been estimated that the nucleus has a rotational period of 5.6759 ± 0.0046 h. [8] The comet at perihelion had a water production of 6×1028 molecules/s. Also when observed in CN featured two side jets in June 2020, but they weren't observed one month later. [9] Concentric structures were observed in the inner coma in May 2020, probably created by a jet with rotation axis towards the Earth. [10]
JPL Horizons using an epoch 1950 orbit solution models that C/2017 T2 took millions of years to come from the Oort cloud at a distance of roughly 74,000 AU (1.2 ly). [1]