A/2017 U1 (formerly C/2017 U1), discovered on October 18, 2017 by the PanSTARRS telescope.
Preprint of our paper
Recent MPEC (designation change!)
Palomar Optical Spectrum of Hyperbolic Near-Earth Object A/2017 U1
Kinematics of the Interstellar Vagabond A/2017 U1
Due to a very large eccentricity ( e=1.2 ) this object might be the first direct visitor from an interstellar space!
Updated orbit Current (November 14, 2017) osculating orbital elements, calculated by M.Królikowska from CBK PAN, Warsaw,Poland, are as follows:
Observational arc: 2017 Oct. 14 — 2017 Nov. 10 Number of observations: 118 RMS: 0.35 arcsec
Heliocentric osculating orbit
Epoch (TT) 20170904.0 = JD2458000.5000 time of perihelion passage (TT) 20170909.488519 ± 0.001243 perihelion distance 0.255234 ± 0.000062 eccentricity 1.199236 ± 0.000164 argument of perihelion [deg] 241.683487 ± 0.011254 longitude of the ascending node [deg] 24.599729 ± 0.000264 inclination [deg] 122.677069 ± 0.005823 inverse semimajor axis [AU-1] -0.780603 ± 0.000618
Mean barycentric original orbit (at 250 AU from the Sun), obtained from the above osculating elements
Epoch (TT) 19730722 time of perihelion passage (TT) 20170909.118037 ± 0.001262 perihelion distance 0.252062 ± 0.000063 eccentricity 1.196488 ± 0.000164 argument of perihelion [deg] 241.696866 ± 0.011361 longitude of the ascending node [deg] 24.251515 ± 0.000251 inclination [deg] 122.725937 ± 0.005995 inverse semimajor axis [AU-1] -0.779521 ± 0.000456
Mean barycentric future orbit (at 250 AU from the Sun), obtained from the above osculating elements
Epoch (TT) 20611028 time of perihelion passage (TT) 20170909.310111 ± 0.001250 perihelion distance 0.257286 ± 0.000063 eccentricity 1.200366 ± 0.000167 argument of perihelion [deg] 241.842028 ± 0.011433 longitude of the ascending node [deg] 24.747600 ± 0.000256 inclination [deg] 122.870243 ± 0.005900 inverse semimajor axis [AU-1] -0.778771 ± 0.000455
Original orbit elements in Galactic frame:
| Name | i | ω | Ω | b | l
|
| C/2017 U1 PanSTARRS | 125° | 167° | 75° | 10° | 262° |
