Scientific assessment of the quality of OSIRIS images

Cécilia Tubiana (1) , Carsten Guettler (1) , G. Kovacs (1) , Ivano Bertini (2) , Dennis Bodewits (3) , Sonia Fornasier (4, 5) , Luisa Lara (6) , F. La Forgia (2) , S. Magrin (7) , M. Pajola (2) , H. Sierks (1) , Cesare Barbieri (7) , Philippe L. Lamy (8) , R. Rodrigo (9, 10) , Detlef Koschny (11) , Hans Rickman (12, 13) , H. U. Keller (14, 15) , Jessica Agarwal (1) , Michael F. A'Hearn (3) , M. A. Barucci (4) , Jean-Loup Bertaux (16) , S. Besse (2) , S. Boudreault (1) , Gabriele Cremonese (17) , Vania da Deppo (18) , B. Davidsson (13) , S. Debei (19) , M. de Cecco (20) , M. R. El-Maarry (21) , Marco Fulle (22) , Olivier Groussin (8) , P. Gutiérrez-Marques (1) , Pedro J. Gutiérrez (6) , N. Hoekzema (1) , M. Hofmann (1) , Stubbe F. Hviid (15, 1) , W-H. Ip (23, 24) , Laurent Jorda (8) , J. Knollenberg (15) , J.-R. Kramm (1) , Ekkehard Kührt (15) , M. Küppers (25) , M. Lazzarin (7) , Jose J. Lopez Moreno (6) , F. Marzari (7) , M. Massironi (2, 26) , H. Michalik (27) , R. Moissl (25) , G. Naletto (28) , Nilda Oklay (1) , F. Scholten (15) , X. Shi (1) , Nicholas Thomas (29, 21) , Jean-Baptiste Vincent (1)

1 MPS - Max-Planck-Institut für Sonnensystemforschung
2 CISAS - Centro di Ateneo di Studi e Attività Spaziali “Giuseppe Colombo”
3 Department of Astronomy [College Park]
4 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
5 UPD7 - Université Paris Diderot - Paris 7
6 IAA - Instituto de Astrofísica de Andalucía
7 Dipartimento di Fisica e Astronomia "Galileo Galilei"
8 LAM - Laboratoire d'Astrophysique de Marseille
9 CAB - Centro de Astrobiologia [Madrid]
10 ISSI - International Space Science Institute [Bern]
11 RSSD - Research and Scientific Support Department, ESTEC
12 CBK - Space Research Centre of Polish Academy of Sciences
13 Department of Physics and Astronomy [Uppsala]
14 IGEP - Institut für Geophysik und Extraterrestrische Physik [Braunschweig]
15 DLR Institute of Planetary Research
16 PLANETO - LATMOS
17 OAPD - INAF - Osservatorio Astronomico di Padova
18 IFN - CNR Institute for Photonics and Nanotechnologies
19 Department of Industrial Engineering [Padova]
20 University of Trento [Trento]
21 Physikalisches Institut [Bern]
22 OAT - INAF - Osservatorio Astronomico di Trieste
23 IANCU - Institute of Astronomy [Taiwan]
24 SSI - Space Science Institute [Macau]
25 Operations Department (ESAC)
26 Dipartimento di Geoscienze [Padova]
27 Institut für Datentechnik und Kommunikationsnetze
28 DEI - Department of Information Engineering [Padova]
29 CSH - Center for Space and Habitability

OSIRIS, the scientific imaging system on board the ESA Rosetta spacecraft, has been imaging the nucleus of comet 67P/Churyumov-Gerasimenko and its dust and gas environment since March 2014. The images serve different scientific goals, from morphology and composition studies of the nucleus surface, to the motion and trajectories of dust grains, the general structure of the dust coma, the morphology and intensity of jets, gas distribution, mass loss, and dust and gas production rates. Aims. We present the calibration of the raw images taken by OSIRIS and address the accuracy that we can expect in our scientific results based on the accuracy of the calibration steps that we have performed. Methods. We describe the pipeline that has been developed to automatically calibrate the OSIRIS images. Through a series of steps, radiometrically calibrated and distortion corrected images are produced and can be used for scientific studies. Calibration campaigns were run on the ground before launch and throughout the years in flight to determine the parameters that are used to calibrate the images and to verify their evolution with time. We describe how these parameters were determined and we address their accuracy. Results. We provide a guideline to the level of trust that can be put into the various studies performed with OSIRIS images, based on the accuracy of the image calibration.

Domains: Instrumentation and Methods for Astrophysic [astro-ph.IM]

Cécilia Tubiana, Carsten Guettler, G. Kovacs, Ivano Bertini, Dennis Bodewits, et al.. Scientific assessment of the quality of OSIRIS images. Astronomy and Astrophysics - A&A, 2015, 583, pp.A46. ⟨10.1051/0004-6361/201525985⟩. ⟨insu-01205893⟩