C/2018 C2 (Lemmon)
The orbit of C/2018 C2 (Lemmon) | |
| Discovery | |
|---|---|
| Discovery site | Mount Lemmon Observatory |
| Discovery date | 5 February 2018 |
| Designations | |
| C/2018 C2, A/2018 C2 | |
| ZC82561 | |
| Orbital characteristics | |
| Epoch | 20 May 2018 (JD 2458258.5) |
| Observation arc | 272 days |
| Earliest precovery date | 28 January 2018 |
| Number of observations | 1,672 |
| Aphelion | ~50,000 AU (inbound) ~5,170 AU (outbound) |
| Perihelion | 1.956 AU |
| Semi-major axis | ~25,700 AU (inbound) ~2,590 AU (outbound) |
| Eccentricity | 0.99992 (inbound) 0.99925 (outbound) |
| Orbital period | ~4.1 million years (inbound) ~130,000 years (outbound) |
| Inclination | 34.453° |
| 91.139° | |
| Argument of periapsis | 134.14° |
| Last perihelion | 2 June 2018 |
| Earth MOID | 1.062 AU |
| Jupiter MOID | 1.405 AU |
| Physical characteristics | |
Mean radius | 4.4±0.5 km |
| 0.04 (assumed) | |
| |
| Comet total magnitude (M1) | 7.6 |
| Comet nuclear magnitude (M2) | 14.8 |
| 15.2 (2018 apparition) | |
C/2018 C2 (Lemmon) is a hyperbolic comet (previously classified as A/2018 C2, a hyperbolic asteroid). It was first observed on 5 February 2018 by the Mount Lemmon Survey conducted at the Mount Lemmon Observatory near Tucson, Arizona. The discovery was announced on 4 March 2018 along with another hyperbolic object, A/2017 U7. On 22 March 2018 it was determined to be a hyperbolic comet.