Concentric structures in the inner coma of comet C/2017 T2 (PANSTARRS)
ATel #13698; Federico Manzini (Stazione Astr. di Sozzago), Paolo Ochner (Uni-PD), Virginio Oldani (Staz. Astr. di Sozzago), Luigi R. Bedin (OAPD-INAF)
on 2 May 2020; 17:23 UT
Distributed as an Instant Email Notice Comets
Credential Certification: Luigi R. Bedin BEDIN (luigi.bedin@inaf.it)
We have been observing comet C/2017 T2 PANSTARRS since January 2019. From the orbital parameters this is identified as a dynamically new comet.
CCD images taken at the Asiago Astrophysical Observatory and the Stazione Astronomica di Sozzago (Italy) have constantly shown an evident jet/fan in the inner coma starting from March 2019 (when the comet was at 5.1 AU from the Sun).
Both around the perihelion and during the last months of observation, the comet did not show an obvious tail in anti-solar direction, but rather a condensation of dust that seems to originate from the jet/fan outflow.
Our latest observation was done with the 1.82m Copernico telescope (OAPD-INAF) of the Asiago Astrophysical Observatory (MPC 098, Italy) on 29.85 April 2020. Following a specific image processing to enhance the weakest details, some circular structures were highlighted, concentric to the comet's optocenter. The stacking of a series of calibrated images taken in B, V, R and Ir shows that these structures are non-repetitive.
This finding may be suggestive of a strong activity modulated by a rotation of the nucleus with a spin axis directed towards the Earth in this period.
Figures and extra material at
https://web.oapd.inaf.it/bedin/files/PAPERs_eMATERIALs/ATel/C2017T2/
Federico Manzini (1), Paolo Ochner (2), Virginio Oldani (1), Luigi R. Bedin (3)
((1) Stazione Astronomica di Sozzago, Cascina Guascona, I-28060 Sozzago (Novara), Italy; (2) Department of Physics and Astronomy-University of Padova, Via F. Marzolo 8, I-35131 Padova, Italy; (3) INAF-Osservatorio Astronomico di Padova, Vicolo dellâOsservatorio 5, I-35122 Padova, Italy)
C/2017 T2 concentric structures
