Towards New Comet Missions

The Rosetta observations have greatly advanced our knowledge of the cometary nucleus and its immediate environment. However, constraints on the mission (both planned and unplanned), the only partially successful Philae lander, and other instrumental issues have inevitably resulted in open questions. Surprising results from the many successful Rosetta observations have also opened new questions, unimagined when Rosetta was first planned. We discuss these and introduce several mission concepts that might address these issues. It is apparent that a sample return mission as originally conceived in the 1980s during the genesis of Rosetta would provide many answers but it is arguable whether it is technically feasible even with today’s technology and knowledge. Less ambitious mission concepts are described to address the suggested main outstanding scientific goals.

[1]  L. Biermann Kometenschweife und solare Korpuskularstrahlung , 1951 .

[2]  M. Kaasalainen,et al.  A Portrait of the Nucleus of Comet 67P/Churyumov-Gerasimenko , 2007 .

[3]  Nicolas Thomas,et al.  REDISTRIBUTION OF PARTICLES ACROSS THE NUCLEUS OF COMET 67P/CHURYUMOV-GERASIMENKO , 2016 .

[4]  R. Honeycutt,et al.  Evidence for interacting gas flows and an extended volatile source distribution in the coma of comet C/1996 B2 (Hyakutake). , 1997, Science.

[5]  C. Pilorget,et al.  67P/Churyumov-Gerasimenko surface properties as derived from CIVA panoramic images , 2015, Science.

[6]  M. Banaszkiewicz,et al.  Thermal and mechanical properties of the near-surface layers of comet 67P/Churyumov-Gerasimenko , 2015, Science.

[7]  S. Debei,et al.  The global meter-level shape model of comet 67P/Churyumov-Gerasimenko , 2017 .

[8]  S. Debei,et al.  The morphological diversity of comet 67P/Churyumov-Gerasimenko , 2015, Science.

[9]  Sukhan Lee,et al.  Interpretation of combined infrared, submillimeter, and millimeter thermal flux data obtained during the Rosetta fly-by of Asteroid (21) Lutetia , 2012 .

[10]  T. Encrenaz,et al.  Subsurface properties and early activity of comet 67P/Churyumov-Gerasimenko , 2015, Science.

[11]  Nicolas Thomas,et al.  Evidence for geologic processes on comets , 2016 .

[12]  Nicolas Altobelli,et al.  Dust particle flux and size distribution in the coma of 67P/Churyumov-Gerasimenko measured in situ by the COSIMA instrument on board Rosetta , 2016 .

[13]  J. Berthelier,et al.  Organics in comet 67P – a first comparative analysis of mass spectra from ROSINA–DFMS, COSAC and Ptolemy , 2017 .

[14]  A. Ercoli Finzi,et al.  SD2 – How To Sample A Comet , 2007 .

[15]  Philippe Lamy,et al.  Physical Properties of Cometary Dust , 1991 .

[16]  M. Knapmeyer,et al.  The Thermal, Mechanical, Structural, and Dielectric Properties of Cometary Nuclei After Rosetta , 2019, Space Science Reviews.

[17]  S. Green,et al.  Implications of the small spin changes measured for large Jupiter-family comet nuclei , 2018, Monthly Notices of the Royal Astronomical Society.

[18]  J. Blum,et al.  Comet formation in collapsing pebble clouds. What cometary bulk density implies for the cloud mass and dust-to-ice ratio , 2016, 1601.05726.

[19]  Roberto Orosei,et al.  The Main Belt Comets and ice in the Solar System , 2017, 1709.05549.

[20]  S. Debei,et al.  Seasonal mass transfer on the nucleus of comet 67P/Chuyumov–Gerasimenko , 2017, 1707.06812.

[21]  Cyril Szopa,et al.  Cosac, The Cometary Sampling and Composition Experiment on Philae , 2007 .

[22]  Ian Wright,et al.  Ptolemy – an Instrument to Measure Stable Isotopic Ratios of Key Volatiles on a Cometary Nucleus , 2007 .

[23]  Alan Fitzsimmons,et al.  The proposed Caroline ESA M3 mission to a Main Belt Comet , 2018, Advances in Space Research.

[24]  D. Plettemeier,et al.  CONSERT suggests a change in local properties of 67P/Churyumov-Gerasimenko's nucleus at depth , 2015 .

[25]  D. Plettemeier,et al.  Direct observations of asteroid interior and regolith structure: Science measurement requirements , 2017, Advances in Space Research.

[26]  Stephan Ulamec,et al.  RoLand: A long-term lander for the Rosetta mission , 1997 .

[27]  Giampiero Naletto,et al.  Dust mass distribution around comet 67P/Churyumov-Gerasimenko determined via parallax measurements using Rosetta's OSIRIS cameras , 2017 .

[28]  C. Chyba,et al.  The heliocentric evolution of cometary infrared spectra: results from an organic grain model. , 1989, Icarus.

[29]  M. Malin,et al.  The Thermal Emission Imaging System (THEMIS) for the Mars 2001 Odyssey Mission , 2004 .

[30]  P. Di Lizia,et al.  Planning and implementation of the on-comet operations of the instrument SD2 onboard the lander Philae of Rosetta mission , 2016 .

[31]  A. Fitzsimmons,et al.  The nucleus of Comet 67P/Churyumov-Gerasimenko. A new shape model and thermophysical analysis , 2012 .

[32]  F. Souvannavong,et al.  Close-up images of the final Philae landing site on comet 67P/Churyumov-Gerasimenko acquired by the ROLIS camera , 2017, 1701.00685.

[33]  S. Debei,et al.  Sublimation of icy aggregates in the coma of comet 67P/Churyumov-Gerasimenko detected with the OSIRIS cameras on board Rosetta. , 2016, 1608.08774.

[34]  R. Rieder,et al.  The Rosetta Alpha Particle X-Ray Spectrometer (APXS) , 2007 .

[35]  Andrew Steele,et al.  Organic compounds on comet 67P/Churyumov-Gerasimenko revealed by COSAC mass spectrometry , 2015, Science.

[36]  H. Balsiger,et al.  Xenon isotopes in 67P/Churyumov-Gerasimenko show that comets contributed to Earth's atmosphere , 2017, Science.

[37]  J. Blum,et al.  Outgassing of icy bodies in the Solar System – II: Heat transport in dry, porous surface dust layers , 2011, 1111.0535.

[38]  G. Sostero,et al.  EPOXI: COMET 103P/HARTLEY 2 OBSERVATIONS FROM A WORLDWIDE CAMPAIGN , 2011 .

[39]  E. Kührt,et al.  Constraining models of activity on comet 67P/Churyumov-Gerasimenko with Rosetta trajectory, rotation, and water production measurements , 2019, Astronomy & Astrophysics.

[40]  F. Scholten,et al.  The landing(s) of Philae and inferences about comet surface mechanical properties , 2015, Science.

[41]  Paul Hartogh,et al.  Ocean-like water in the Jupiter-family comet 103P/Hartley 2 , 2011, Nature.

[42]  Andrew F. Cheng,et al.  The Comet Nucleus Tour (Contour) , 2002 .

[43]  Edward J. Smith,et al.  Encounter of the Ulysses Spacecraft with the Ion Tail of Comet MCNaught , 2007 .

[44]  Ian Wright,et al.  Ptolemy operations at the surface of a comet, from planning to reality , 2016 .

[45]  R. Schulz,et al.  The 67P/Churyumov–Gerasimenko observation campaign in support of the Rosetta mission , 2017, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[46]  D. Plettemeier,et al.  The Comet Nucleus Sounding Experiment by Radiowave Transmission (CONSERT): A Short Description of the Instrument and of the Commissioning Stages , 2007 .

[47]  Erik Asphaug,et al.  Structure of Comet Shoemaker-Levy 9 Inferred from the Physics of Tidal Breakup , 1996 .

[48]  Matthias Hahn,et al.  The Nucleus of comet 67P/Churyumov–Gerasimenko – Part I: The global view – nucleus mass, mass-loss, porosity, and implications , 2018, Monthly Notices of the Royal Astronomical Society.

[49]  J. De Keyser,et al.  Sulphur isotope mass-independent fractionation observed in comet 67P/Churyumov–Gerasimenko by Rosetta/ROSINA , 2017 .

[50]  David Kappel,et al.  Comet 67P/CG Nucleus Composition and Comparison to Other Comets , 2019, Space Science Reviews.

[51]  Luigi Colangeli,et al.  COMET 67P/CHURYUMOV–GERASIMENKO: CLOSE-UP ON DUST PARTICLE FRAGMENTS , 2016 .

[52]  A. Morbidelli,et al.  Origin and Evolution of Short-period Comets , 2017, 1706.07447.

[53]  S. Debei,et al.  Spectrophotometric properties of the nucleus of comet 67P/Churyumov-Gerasimenko from the OSIRIS instrument onboard the ROSETTA spacecraft , 2015, 1505.06888.

[54]  J. Sunshine,et al.  Asymmetries in the distribution of H2O and CO2 in the inner coma of Comet 9P/Tempel 1 as observed by Deep Impact , 2007 .

[55]  Giuseppe Piccioni,et al.  The global surface composition of 67P/Churyumov–Gerasimenko nucleus by Rosetta/VIRTIS. II) Diurnal and seasonal variability , 2016 .

[56]  S. Debei,et al.  Possible interpretation of the precession of comet 67P/Churyumov-Gerasimenko , 2016 .

[57]  Johannes Benkhoff,et al.  The Comet Nucleus Tour (Contour); A NASA Discovery Mission , 2000 .

[58]  S. Debei,et al.  Regional unit definition for the nucleus of comet 67P/Churyumov-Gerasimenko on the SHAP7 model , 2018, Planetary and Space Science.

[59]  D. J. Andrews,et al.  CHO-bearing organic compounds at the surface of 67P/Churyumov-Gerasimenko revealed by Ptolemy , 2015, Science.

[60]  S. Debei,et al.  Two independent and primitive envelopes of the bilobate nucleus of comet 67P , 2015, Nature.

[61]  Stavro Ivanovski,et al.  Aspherical dust dynamics code for GIADA experiment in the coma of 67P/Churyumov-Gerasimenko , 2014 .

[62]  P. Encrenaz,et al.  A porosity gradient in 67P/C-G nucleus suggested from CONSERT and SESAME-PP results: an interpretation based on new laboratory permittivity measurements of porous icy analogues , 2016 .

[63]  U. Fink,et al.  Virtis: An Imaging Spectrometer for the Rosetta Mission , 2007 .

[64]  Ludmilla Kolokolova,et al.  Analysis of the dust jet imaged by Rosetta VIRTIS-M in the coma of comet 67P/Churyumov-Gerasimenko on 2015 April 12 , 2016 .

[65]  Dominic J. Benford,et al.  Long-term Evolution of the Outgassing of Comet Hale-Bopp From Radio Observations , 1997 .

[66]  S. Debei,et al.  Constraints on cometary surface evolution derived from a statistical analysis of 67P’s topography , 2017, 1707.00734.

[67]  Anita L. Cochran,et al.  Comet Hopper: A Mission Concept for Exploring the Heterogeneity of Comets , 2008 .

[68]  K. Glassmeier,et al.  The Rosetta Mission: Flying Towards the Origin of the Solar System , 2007 .

[69]  E. Grün,et al.  Comet nucleus sounding experiment by radiowave transmission , 1998 .

[70]  T. Encrenaz,et al.  MIRO: Microwave Instrument for Rosetta Orbiter , 2007 .

[71]  Andrew S. Rivkin,et al.  The Main-belt Asteroid and NEO Tour with Imaging and Spectroscopy (MANTIS) , 2015, 2016 IEEE Aerospace Conference.

[72]  S. Debei,et al.  Surface changes on comet 67P/Churyumov-Gerasimenko suggest a more active past , 2017, Science.

[73]  J. Biele,et al.  Hopper concepts for small body landers , 2011 .

[74]  Stephan Ulamec,et al.  COSAC prepares for sampling and in situ analysis of cometary matter from comet 67P/Churyumov-Gerasimenko , 2014 .

[75]  Peter H. Schultz,et al.  The detection, localization, and dynamics of large icy particles surrounding Comet 103P/Hartley 2 , 2012 .

[76]  Giampiero Naletto,et al.  Morphology and dynamics of the jets of comet 67P/Churyumov-Gerasimenko: Early-phase development , 2015 .

[77]  S. Debei,et al.  The pristine interior of comet 67P revealed by the combined Aswan outburst and cliff collapse , 2017, Nature Astronomy.

[78]  Helmut Wiesemeyer,et al.  Terrestrial deuterium-to-hydrogen ratio in water in hyperactive comets , 2019, Astronomy & Astrophysics.

[79]  R. Trautner,et al.  Sesame – An Experiment of the Rosetta Lander Philae: Objectives and General Design , 2007 .

[80]  Jean-Marc Petit,et al.  A cometary nucleus model taking into account all phase changes of water ice: amorphous, crystalline, and clathrate , 2012 .

[81]  Nicolas Thomas,et al.  The SCITEAS experiment: Optical characterizations of sublimating icy planetary analogues , 2015 .

[82]  Hans-Herbert Fischer,et al.  Electrical properties and porosity of the first meter of the nucleus of 67P/Churyumov-Gerasimenko - As constrained by the Permittivity Probe SESAME-PP/Philae/Rosetta , 2016, 1604.03678.

[83]  J. Licandro,et al.  Castalia - A Mission to a Main Belt Comet , 2014 .

[84]  Michael Lange,et al.  MASCOT—The Mobile Asteroid Surface Scout Onboard the Hayabusa2 Mission , 2017 .

[85]  Joseph M. Hahn,et al.  Completing the inventory of the solar system , 1996 .

[86]  J. Blum,et al.  The stratification of regolith on celestial objects , 2015, 1505.02923.

[87]  Jens Biele,et al.  Rosetta Lander - Landing and operations on comet 67P/Churyumov-Gerasimenko , 2016 .

[88]  Kuninori Uesugi,et al.  SOCCER-Comet Coma Sample Return Mission , 1994 .

[89]  Urs Mall,et al.  Change of outgassing pattern of 67P/Churyumov–Gerasimenko during the March 2016 equinox as seen by ROSINA , 2017 .

[90]  A. ERCOLI FINZI,et al.  SD 2 – HOW TO SAMPLE A COMET , 2007 .

[91]  Josep M. Trigo-Rodríguez Meteorites and the early solar system II, edited by Dante S. Lauretta and Harry Y. McSween, Jr. , 2008 .

[92]  J. Crifo,et al.  Asymptotics for spherical particle motion in a spherically expanding flow , 2018, Icarus.

[93]  F. Scholten,et al.  The structure of the regolith on 67P/Churyumov-Gerasimenko from ROLIS descent imaging , 2015, Science.

[94]  M. Belton,et al.  The temperature, thermal inertia, roughness and color of the nuclei of Comets 103P/Hartley 2 and 9P/Tempel 1 , 2013 .

[95]  Martin Rubin,et al.  Isotopic composition of CO 2 in the coma of 67P/Churyumov-Gerasimenko measured with ROSINA/DFMS , 2017 .

[96]  S. Debei,et al.  Tensile strength of 67P/Churyumov-Gerasimenko nucleus material from overhangs (Corrigendum) , 2017, Astronomy & Astrophysics.

[97]  D. J. Lien,et al.  Dust in comets. I, Thermal properties of homogeneous and heterogeneous grains , 1990 .

[98]  Cesare Barbieri,et al.  The dust environment of comet 67P/Churyumov-Gerasimenko , 2004 .

[99]  S. Debei,et al.  Acceleration of individual, decimetre-sized aggregates in the lower coma of comet 67P/Churyumov-Gerasimenko , 2016, 1608.07933.

[100]  D. Möhlmann,et al.  Surface Regolith and Environment of Comets , 1994 .

[101]  Giampiero Naletto,et al.  OSIRIS observations of meter-sized exposures of H2O ice at the surface of 67P/Churyumov-Gerasimenko and interpretation using laboratory experiments , 2015 .

[102]  Walter F. Huebner,et al.  Simulation Experiments with Cometary Analogous Material , 1998 .

[103]  Martin Rubin,et al.  Inventory of the volatiles on comet 67P/Churyumov-Gerasimenko from Rosetta/ROSINA , 2015 .

[104]  J. Blum,et al.  Micrometer-sized ice particles for planetary-science experiments - I. Preparation, critical rolling friction force, and specific surface energy , 2011, 1102.0430.

[105]  S. F. Green,et al.  Rotation of cometary nuclei: new light curves and an update of the ensemble properties of Jupiter-family comets , 2017, 1707.02133.

[106]  M. Banaszkiewicz,et al.  Mupus – A Thermal and Mechanical Properties Probe for the Rosetta Lander Philae , 2007 .

[107]  Giuseppe Piccioni,et al.  Investigation into the disparate origin of CO2 and H2O outgassing for Comet 67/P , 2016 .

[108]  J. De Keyser,et al.  Abundant molecular oxygen in the coma of comet 67P/Churyumov–Gerasimenko , 2015, Nature.

[109]  D. Plettemeier,et al.  Properties of the 67P/Churyumov-Gerasimenko interior revealed by CONSERT radar , 2015, Science.

[110]  R. Hancock,et al.  The Nucleus , 2008, Methods in Molecular Biology.

[111]  Eric Hand NASA set to choose low-cost Solar System mission , 2012, Nature.

[112]  S. Debei,et al.  The highly active Anhur–Bes regions in the 67P/Churyumov–Gerasimenko comet: results from OSIRIS/ROSETTA observations , 2017, 1707.02945.

[113]  S. Debei,et al.  Linking surface morphology, composition, and activity on the nucleus of 67P/Churyumov-Gerasimenko , 2018, Astronomy & Astrophysics.

[114]  J. Licandro,et al.  Thermal properties, sizes, and size distribution of Jupiter-family cometary nuclei , 2013, 1307.6191.

[115]  Stephan Ulamec,et al.  Rosetta Lander-Philae: Operations on comet 67P/Churyumov-Gerasimenko, Analysis of wake-up activities and final state , 2017 .

[116]  Wlodek Kofman,et al.  CONSERT constrains the internal structure of 67P at a few metres size scale , 2017 .

[117]  S. Debei,et al.  On deviations from free-radial outflow in the inner coma of comet 67P/Churyumov–Gerasimenko , 2018, Icarus.

[118]  S. Debei,et al.  Evidence of sub-surface energy storage in comet 67P from the outburst of 2016 July 03 , 2017, 1710.10235.

[119]  J. Lasue,et al.  Cosmochemical implications of CONSERT permittivity characterization of 67P/CG , 2016 .

[120]  K. Klaasen,et al.  Thermal Inertia and Surface Roughness of Comet 9P/Tempel 1 Derived from Recalibrated Deep Impact NIR Spectroscopy , 2010 .

[121]  P. Michel,et al.  Asteroid Impact and Deflection Assessment mission , 2015 .

[122]  P. Michel,et al.  Asteroid Impact & Deflection Assessment mission: Kinetic impactor , 2016 .

[123]  K. Schmidt,et al.  The tensile strength of ice and dust aggregates and its dependence on particle properties , 2018, Monthly Notices of the Royal Astronomical Society.

[124]  Ludmilla Kolokolova,et al.  Cometary Science with the James Webb Space Telescope , 2015, 1510.05878.

[125]  Harry Lehto,et al.  Carbon-rich dust in comet 67P/Churyumov-Gerasimenko measured by COSIMA/Rosetta , 2017 .

[126]  J. Bibring,et al.  Rosetta lander in situ characterization of a comet nucleus , 1999 .

[127]  G. Naletto,et al.  CASTAway: An asteroid main belt tour and survey , 2017, Advances in Space Research.

[128]  Stephan Ulamec,et al.  Capabilities of Philae, the Rosetta Lander , 2008 .

[129]  U. Fink,et al.  Virtis : an imaging spectrometer for the rosetta mission , 1998 .

[130]  E. Neefs,et al.  67P/Churyumov-Gerasimenko, a Jupiter family comet with a high D/H ratio , 2015, Science.

[131]  Antti Näsilä,et al.  European component of the AIDA mission to a binary asteroid: Characterization and interpretation of the impact of the DART mission , 2018, Advances in Space Research.

[132]  Stefano Mottola,et al.  Observing and modeling the near-nucleus coma structure around terminators on 67P/Churyumov-Gerasimenko , 2017 .

[133]  Giuseppe Piccioni,et al.  Water and carbon dioxide distribution in the 67P/Churyumov-Gerasimenko coma from VIRTIS-M infrared observations , 2016 .

[134]  Hideyo Kawakita,et al.  Cometary Isotopic Measurements , 2015 .

[135]  F. Scholten,et al.  A comparison of multiple Rosetta data sets and 3D model calculations of 67P/Churyumov-Gerasimenko coma around equinox (May 2015) , 2019, Icarus.

[136]  M. C. Kochte,et al.  Initial results from the New Horizons exploration of 2014 MU69, a small Kuiper Belt object , 2019, Science.

[137]  Carl Sagan,et al.  Infrared emission by organic grains in the coma of comet Halley , 1987, Nature.

[138]  Robert L. Millis,et al.  The ensemble properties of comets: Results from narrowband photometry of 85 comets , 1995 .

[139]  Geronimo L. Villanueva,et al.  Primitive Object Volatile Explorer (PrOVE) — Waypoints and Opportunistic Deep Space Missions to Comets , 2018 .

[140]  E. Kührt,et al.  Time variability and heterogeneity in the coma of 67P/Churyumov-Gerasimenko , 2015, Science.