C/2018 C2 (Lemmon)
Discovery [1][2] | |
---|---|
Discovered by | Mount Lemmon Srvy. |
Discovery site | Mount Lemmon Obs. |
Discovery date | 5 February 2018 (first observed only) |
Designations | |
C/2018 C2 (Lemmon) | |
ZC82561, A/2018 C2 | |
hyperbolic comet [3] | |
Orbital characteristics [3] | |
Epoch 20 May 2018 (JD 2458258.5) | |
Observation arc | 272 days |
Perihelion | 1.9565 |
−1083±3 | |
Eccentricity | 1.0018 0.99924 (Barycentric epoch 2200)[4] |
≈ 130,000 years (outbound)[4] | |
-0.00036 | |
0° 0m 0.072s / day | |
Inclination | 34.453° |
91.14° | |
134.14° | |
Earth MOID | 1.062 |
Jupiter MOID | 1.405 |
Physical characteristics | |
Dimensions | 1.7–7.6 km (assumed) |
19.0 (March 2018) | |
15.1±0.63 | |
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, in the United States.[1] The discovery was announced on 4 March 2018 along with another hyperbolic object, A/2017 U7.[2] Based on the absolute magnitude of 15.1, it may measure several kilometers in diameter.[5] On 22 March 2018 it was determined to be a hyperbolic comet.[6]
Orbit
[edit]While near perihelion, A/2018 C2's heliocentric orbit is not bound to the Solar System, unlike ʻOumuamua, it is not an interstellar object. The heliocentric eccentricity drops below 1 starting with an epoch of January 2023,[7] when it is 13.8
As of March 2018[update], A/2018 C2 was inbound 2.2
Notes
[edit]- ^ Objects on hyperbolic trajectories have negative semimajor axis, giving them a positive orbital energy.
References
[edit]- ^ a b "C/2018 C2". Minor Planet Center. Retrieved 5 March 2018.
- ^ a b c "MPEC 2018-E18 : A/2018 C2". IAU Minor Planet Center. 4 March 2018. Retrieved 4 March 2018. (AK18C020)
- ^ a b c "JPL Small-Body Database Browser: (A/2018 C2)" (2018-02-27 last obs.). Jet Propulsion Laboratory. Archived from the original on 5 March 2018. Retrieved 5 March 2018.
- ^ a b c d Horizons output. "Barycentric Osculating Orbital Elements for Comet C/2018 C2 (Lemmon)". Retrieved 15 October 2022.
- ^ "Asteroid Size Estimator". Jet Propulsion Laboratory. Retrieved 5 March 2018.
- ^ "MPEC 2018-F136: COMET C/2018 C2 (Lemmon)". IAU Minor Planet Center. 28 March 2018. Retrieved 28 March 2018. (CK18C020)
- ^ Horizons output. "Heliocentric orbit of Comet C/2018 C2 (Lemmon) becoming CLOSED in January 2023". Retrieved 16 October 2022.
- ^ a b Hui, Man-To (27 July 2018). "Two Hyperbolic Baldheads in the Solar System: 2017 U7 and 2018 C2". The Astronomical Journal. 156 (2): 73. arXiv:1806.06904. Bibcode:2018AJ....156...73H. doi:10.3847/1538-3881/aacdf3. S2CID 250760308.
- ^ "JPL Small-Body Database Search Engine: comets and e > 1". Jet Propulsion Laboratory Solar System Dynamics. Retrieved 4 March 2018.
External links
[edit]- C/2018 C2 at the JPL Small-Body Database