Nixon, Conor A., James Abshire, Andrew Ashton, Barnes, Jason W., Nathalie Carrasco, Mathieu Choukroun, Athena Coustenis, Louis-Alexandre Couston, Edberg, Niklas J. T., Alexander Gagnon, Hofgartner, Jason D., Luciano Iess, Stéphane Le Mouélic, Rosaly Lopes, Juan Lora, Lorenz, Ralph D., Adrienn Luspay-Kuti, Michael Malaska, Kathleen Mandt, Marco Mastrogiuseppe, Erwan Mazarico, Marc Neveu, Taylor Perron, Jani Radebaugh, Sébastien Rodriguez, Farid Salama, Ashley Schoenfeld, Soderblom, Jason M., Anezina Solomonidou, Darci Snowden, Xioali Sun, Nicholas Teanby, Gabriel Tobie, Trainer, Melissa G., Tucker, Orenthal J., Turtle, Elizabeth P., Sandrine Vinatier, Véronique Vuitton, Xi Zhang, GSFC Planetary Systems Laboratory, NASA Goddard Space Flight Center (GSFC), Woods Hole Oceanographic Institution (WHOI), University of Idaho [Moscow, USA], PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Swedish Institute of Space Physics [Uppsala] (IRF), School of Oceanography [Seattle], University of Washington [Seattle], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Yale University [New Haven], Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), University of Maryland [Baltimore], Massachusetts Institute of Technology (MIT), Brigham Young University (BYU), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), NASA Ames Research Center (ARC), University of California [Los Angeles] (UCLA), University of California, European Space Astronomy Centre (ESAC), European Space Agency (ESA), Central Washington University, School of Earth Sciences [Bristol], University of Bristol [Bristol], Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), and University of California [Santa Cruz] (UCSC)
13 pages, white paper submitted to the NRC Decadal Survey for Planetary Science and Astrobiology; International audience; We outline a flagship-class mission concept focused on studying Titan as a global system, with particular emphasis on the polar regions. Investigating Titan from the unique standpoint of a polar orbit would enable comprehensive global maps to uncover the physics and chemistry of the atmosphere, and the topography and geophysical environment of the surface and subsurface. The mission includes two key elements: (1) an orbiter spacecraft, which also acts as a data relay, and (2) one or more small probes to directly investigate Titan's seas and make the first direct measurements of their liquid composition and physical environment. The orbiter would carry a sophisticated remote sensing payload, including a novel topographic lidar, a long-wavelength surface-penetrating radar, a sub-millimeter sounder for winds and for mesospheric/thermospheric composition, and a camera and near-infrared spectrometer. An instrument suite to analyze particles and fields would include a mass spectrometer to focus on the interactions between Titan's escaping upper atmosphere and the solar wind and Saturnian magnetosphere. The orbiter would enter a stable polar orbit around 1500 to 1800 km, from which vantage point it would make global maps of the atmosphere and surface. One or more probes, released from the orbiter, would investigate Titan's seas in situ, including possible differences in composition between higher and lower latitude seas, as well as the atmosphere during the parachute descent. The number of probes, as well as the instrument complement on the orbiter and probe, remain to be finalized during a mission study that we recommend to NASA as part of the NRC Decadal Survey for Planetary Science now underway, with the goal of an overall mission cost in the "small flagship" category of ~$2 bn. International partnerships, similar to Cassini-Huygens, may also be included for consideration.