Journal articles: 'Mission Cassini-Huygens'

1

Sollazzo, C., J. Rakiewicz, and R. D. Wills. "Cassini-Huygens: Mission operations." Control Engineering Practice 3, no. 11 (November 1995): 1631–40. http://dx.doi.org/10.1016/0967-0661(95)00174-s.

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Lebreton, J. P., and D. L. Matson. "The Huygens Mission to Titan: Overview and status." Highlights of Astronomy 13 (2005): 905. http://dx.doi.org/10.1017/s1539299600017500.

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Huygens is an entry probe designed to descend under parachute through the atmosphere of Titan, Saturn’s largest moon. The Huygens Probe is provided by the European Space Agency (ESA) for the Cassini/Huygens mission to Saturn and Titan. The Huygens mission will be conducted on the 3rd Orbit around Saturn. The probe will be released around December 25, 2004 for entry in Titan on January 14, 2005. This paper provided an overview of the Huygens mission. The status of the probe and of the mission was reviewed, and opportunities for Titan observations by the Orbiter during the first two orbits were discussed. The Cassini/Huygens mission is a joint undertaking by NASA and ESA, with ASI as a partner via a bilateral agreement with NASA.

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Lebreton, Jean-Pierre, and Dennis Matson. "The Cassini-Huygens Mission (Part I)." Space Research Today 169 (August 2007): 11–19. http://dx.doi.org/10.1016/s1752-9298(07)80035-1.

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Matson, Dennis L., Jean-Pierre Lebreton, and Linda Spilker. "Cassini/Huygens Mission To Saturn: Results And Prospects." Highlights of Astronomy 13 (2005): 904. http://dx.doi.org/10.1017/s1539299600017494.

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The Cassini spacecraft was launched in October, 1997. Since then it has been on an interplanetary trajectory aimed toward Saturn and arriving there on July 1, 2004. En route, Cassini has flown by Venus, the Earth, and Jupiter. Each of these events yielded new scientific results, (e.g., 11 papers in J. Geophys. Res. 106, 30099-30279.) The Cassini flyby of Jupiter, with Galileo already in Jovian orbit, enabled the first-ever simultaneous measurements by two spacecraft at an outer planet. This fortuitous event provided a unique opportunity to investigate the giant planet’s magnetic field and the properties of the Jovian system. It provided a focused period for intensive observations of Jupiter and cooperation with investigators using Galileo, Hubble, Chandra, and ground-based observatories. The results achieved at Jupiter were stunning (e.g., 8 articles in Nature 415, 965-1005, February 28, 2002). Recent results and the current status of the spacecraft and mission will be discussed. Of note are the dates of July 1, 2004 when Cassini goes into orbit about Saturn and January 14, 2005 when Huygens enters the atmosphere of Titan. The Cassini/Huygens mission is a joint undertaking by NASA and ESA, with ASI as a partner via a bilateral agreement with NASA.

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Spilker, Linda. "Cassini-Huygens’ exploration of the Saturn system: 13 years of discovery." Science 364, no. 6445 (June 13, 2019): 1046–51. http://dx.doi.org/10.1126/science.aat3760.

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The Cassini-Huygens mission to Saturn provided a close-up study of the gas giant planet, as well as its rings, moons, and magnetosphere. The Cassini spacecraft arrived at Saturn in 2004, dropped the Huygens probe to study the atmosphere and surface of Saturn’s planet-sized moon Titan, and orbited Saturn for the next 13 years. In 2017, when it was running low on fuel, Cassini was intentionally vaporized in Saturn’s atmosphere to protect the ocean moons, Enceladus and Titan, where it had discovered habitats potentially suitable for life. Mission findings include Enceladus’ south polar geysers, the source of Saturn’s E ring; Titan’s methane cycle, including rain that creates hydrocarbon lakes; dynamic rings containing ice, silicates, and organics; and Saturn’s differential rotation. This Review discusses highlights of Cassini’s investigations, including the mission’s final year.

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FERRI, F., F. ANGRILLI, G. BIANCHINI, M. FULCHIGNONI, and HASI TEAM. "HUYGENS ATMOSPHERIC STRUCTURE INSTRUMENT OF HUYGENS PROBE ON CASSINI MISSION." Acta Astronautica 50, no. 4 (February 2002): 249–55. http://dx.doi.org/10.1016/s0094-5765(01)00161-8.

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Jaffe, Leonard D., and Linda M. Herrell. "Cassini/Huygens Science Instruments, Spacecraft, and Mission." Journal of Spacecraft and Rockets 34, no. 4 (July 1997): 509–21. http://dx.doi.org/10.2514/2.3241.

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8

Bertotti, B. "An introduction to the Cassini-Huygens mission." Il Nuovo Cimento C 15, no. 6 (November 1992): 1129–32. http://dx.doi.org/10.1007/bf02506706.

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9

Bergen, Thomas, Harry Himelblau, and Dennis Kern. "Development of Acoustic Test Criteria for the Cassini Spacecraft." Journal of the IEST 41, no. 1 (January 14, 1998): 26–38. http://dx.doi.org/10.17764/jiet.41.1.77v54517021l5941.

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Acoustic measurements from eight Titan IV flights, and an acoustic test of a Cassini simulator and Titan payload fairing (PLF), were used to derive acoustic flight and test criteria for the Cassini spacecraft. The flight and laboratory data were used or modified to account for the following factors: (a) noise-spike contamination of flight data, (b) spatial and flight-to-flight variations of flight data, (c) application of a thicker barrier-blanket to the PLF for the Cassini mission, (d) effects of locating two Cassini assemblies, the Huygens Probe (HP), and the High Gain Antenna (HGA), near the PLF, and (e) higher thrust of upgraded Titan solid rocket motors (SRMs) for the Cassini mission. An overall sound pressure level of 145 dB was verified for the protoflight acoustic test criteria for the Cassini spacecraft.

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Gavaghan, H. "CASSINI-HUYGENS: Mission to Saturn Rises From Ashes." Science 293, no. 5528 (July 13, 2001): 193a—193. http://dx.doi.org/10.1126/science.293.5528.193a.

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Flamini, E., and R. Somma. "Italian participation to interplanetary exploration: The Cassini-Huygens mission." Acta Astronautica 44, no. 2-4 (January 1999): 201–4. http://dx.doi.org/10.1016/s0094-5765(99)00049-1.

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Franco-Ferreira, E. A., G. M. Goodwin, T. G. George, and G. H. Rinehart. "Long Life Radioisotopic Power Sources Encapsulated in Platinum Metal Alloys." Platinum Metals Review 41, no. 4 (October 1, 1997): 154–63. http://dx.doi.org/10.1595/003214097x414154163.

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The platinum metals alloys, DOP-26 iridium and platinum-30 per cent rhodium, have been successfully used to encapsulate plutonia fuel pellets for the Cassini Spacecraft. The iridium-encapsulated heat sources provide approximately 900 watts of electrical power for the spacecraft and its experiments, whereas the platinum alloy clad pellets will supply about 150 watts of heat to various parts of the spacecraft and its lunar probe, Huygens. The particular alloys used on this mission have been selected to fulfil the critical function of maintaining fuel containment during normal service and for projected malfunction or accident scenarios. Their ability to perform satisfactorily has been demonstrated through extensive testing of their mechanical, physical and impact properties. The Cassini heat source manufacturing yields were significantly higher than those obtained for previous missions.

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13

Schilling, Klaus. "THE CASSINI / HUYGENS SPACE MISSION TO EXPLORE THE SATURNIAN SYSTEM." IFAC Proceedings Volumes 38, no. 1 (2005): 151–56. http://dx.doi.org/10.3182/20050703-6-cz-1902.01986.

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14

Raulin, F., P. Coll, D. Coscia, M. C. Gazeau, R. Sternberg, P. Bruston, G. Israel, and D. Gautier. "An exobiological view of Titan and the Cassini-Huygens mission." Advances in Space Research 22, no. 3 (January 1998): 353–62. http://dx.doi.org/10.1016/s0273-1177(98)00193-8.

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AlDabbas, Ashraf, and Zoltan Gal. "Cassini-Huygens mission images classification framework by deep learning advanced approach." International Journal of Electrical and Computer Engineering (IJECE) 11, no. 3 (June 1, 2021): 2457. http://dx.doi.org/10.11591/ijece.v11i3.pp2457-2466.

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Developing a deep learning (DL) model for image classification commonly demands a crucial architecture organization. Planetary expeditions produce a massive quantity of data and images. However, manually analyzing and classifying flight missions image databases with hundreds of thousands of images is ungainly and yield weak accuracy. In this paper, we speculate an essential topic related to the classification of remotely sensed images, in which the process of feature coding and extraction are decisive procedures. Diverse feature extraction techniques are intended to stimulate a discriminative image classifier. Features extraction is the primary engagement in raw data processing with the purpose of data classification; when it comes across the task of analysis of vast and varied data, these kinds of tasks are considered as time-consuming and hard to be treated with. Most of these classifiers are either, in principle, quite intricate or virtually unattainable to calculate for massive datasets. Stimulated by this perception, we put forward a straightforward, efficient classifier based on feature extraction by analyzing the cell of tensors via layered MapReduce framework beside meta-learning LSTM followed by a SoftMax classifier. Experiment results show that the provided model attains a classification accuracy of 96.7%, which makes the provided model quite valid for diverse image databases with varying sizes.

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Coustenis, Athena. "The Cassini-Huygens Mission And Its Exploration Of The Saturnian System." Archives Internationales d'Histoire des Sciences 72, no. 189 (July 2022): 230–59. http://dx.doi.org/10.1484/j.arihs.5.133713.

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17

Raulin, François, Patrice Coll, Marie-Claire Gazeau, and Paul Bruston. "Prebiotic-Related Chemistry in the Present Outer Solar System." International Astronomical Union Colloquium 161 (January 1997): 401–12. http://dx.doi.org/10.1017/s0252921100014913.

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AbstractThere are numerous places in the outer solar system where the formation of the starting ingredients which are involved in the early terrestrial prebiotic chemistry is currently going on. Organic chemistry is largely present in the outer planets, particularly in Titan. Titan has a dense atmosphere, mainly composed of N2and CH4and very rich in organic compounds, both in gas and aerosol phases. Because of the low temperature of Titan’s environment, liquid water is currently absent from the satellite and compounds of low stability at the (Earth) laboratory temperature, and very reactive, are still or may be present. However, Titan study should provide information on prebiotic chemistry – at least prebiotic chemistry in absence of liquid water. This quasi-planet thus appears as a natural laboratory enabling to study prebiotic evolution toward complex organic systems in a planetary environment over a long time scale. A detailed study of such a natural prebiotic laboratory is precisely one of the main objectives of the Cassini-Huygens mission. With the sending of the Cassini orbiter around Saturn and the Huygens probe in the atmosphere of Titan, this mission, due to be launched in October 1997, for a Saturn arrival in 2004, will offer a unique opportunity to study in detail extra-terrestrial prebiotic processes, together with important implications in the field of bioastronomy and the origins of life.

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18

Schilling, K. "Control aspects of interplanetary spacecraft — An introduction to the Cassini/Huygens mission." Control Engineering Practice 3, no. 11 (November 1995): 1599–601. http://dx.doi.org/10.1016/0967-0661(95)00170-y.

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19

Magalhães, Fabíola P., Gerardo G. B. de Souza, and Heloisa M. Boechat-Roberty. "Photoabsorption of hydrocarbons in Titan's atmosphere." Proceedings of the International Astronomical Union 5, H15 (November 2009): 678–79. http://dx.doi.org/10.1017/s1743921310010914.

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AbstractTitan, the largest satellite of the planet Saturn, has a thick atmosphere which consists of nitrogen (N2) and methane (CH4). In 2004, the Cassini-Huygens mission observed the occultation of two stars through the atmosphere of Titan and measured ultraviolet (UV) absorption spectra. Through these spectra it was possible to identify the molecular species contained in this environment. In the present work, we have simulated a spectrum of this atmosphere using some molecules such as CH4, C2H2, C2H4, C2H6, C4H2, and C6H6. Our cross sections data were experimentally obtained using the electron energy-loss technique, where the electron energy-loss spectra, measured high incident energies and in small scattering angles, are similar to photoabsorption spectra. The comparison of our synthetic spectrum with that measured by Cassini shows that this method is very efficient for identifying molecules as well as estimating abundances.

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20

Seaton, K. Marshall, Szilárd Gyalay, Gaia Stucky de Quay, Ethan R. Burnett, C. Adeene Denton, Bryce Doerr, Kamak Ebadi, et al. "Astrobiology eXploration at Enceladus (AXE): A New Frontiers Mission Concept Study." Planetary Science Journal 4, no. 6 (June 1, 2023): 116. http://dx.doi.org/10.3847/psj/acd119.

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Abstract The Saturnian moon Enceladus presents a unique opportunity to sample the contents of a subsurface liquid water ocean in situ via the continuous plume formed over its south polar terrain using a multi-flyby mission architecture. Previous analyses of the plume’s composition by Cassini revealed an energy-rich system laden with salts and organic compounds, representing an environment containing most of the ingredients for life as we know it. Following in the footsteps of the Cassini-Huygens mission, we present Astrobiology eXploration at Enceladus (AXE), a New Frontiers class Enceladus mission concept study carried out during the 2021 NASA Planetary Science Summer School program at the Jet Propulsion Laboratory, California Institute of Technology. We demonstrate that a scientifically compelling geophysical and life-detection mission to Enceladus can be carried out within the constraints of a New Frontiers-5 cost cap using a modest instrument suite, requiring only a narrow angle, high-resolution telescopic imager, a mass spectrometer, and a high-gain antenna for radio communications and gravity science measurements. Using a multi-flyby mission architecture, AXE would evaluate the habitability and potential for life at Enceladus through a synergistic combination of in situ chemical analysis measurements aimed at directly detecting the presence of molecular biosignatures, along with geophysical and geomorphological investigations to contextualize chemical biosignatures and further evaluate the habitability of Enceladus over geologic time.

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21

Strobel, Darrell F. "Hydrogen and methane in Titan’s atmosphere: chemistry, diffusion, escape, and the Hunten limiting flux principle 1This article is part of a Special Issue that honours the work of Dr. Donald M. Hunten FRSC who passed away in December 2010 after a very illustrious career." Canadian Journal of Physics 90, no. 8 (August 2012): 795–805. http://dx.doi.org/10.1139/p11-131.

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One of Professor Donald M. Hunten’s lasting contributions to the field of planetary atmospheres was the principle of the (Hunten) limiting flux, where the escape of light species is limited by the rate at which they can diffuse through the atmosphere. While his limiting flux expression has been well tested for hydrogen’s escape from the Earth’s atmosphere (e.g., Hunten and Strobel (J. Atmos. Sci. 31, 305 (1974)); Hunten and Donahue (Ann. Rev. Earth Planet Sci. 4, 265 (1976))), it has not been tested for Titan’s atmosphere, which was the original motivation for the principle. The Cassini–Huygens mission has provided sufficient data on the variation of the H2 mole fraction with altitude to test its applicability and validity. Only in the vicinity of the homopause does the limiting flux expression yield the actual H2 escape flux, because the mole fraction varies with altitude. This paper deals also with our current understanding of the three major constituents of Titan’s atmosphere (N2, CH4, and H2) from the various measurements by instruments on the Cassini orbiter and the Huygens probe. Specific problems addressed are additional required sources of H2, the CH4 escape rate, and the possible role of energetic electron and ion precipitation from Saturn’s magnetosphere.

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Teanby, Nicholas A., Patrick G. J. Irwin, Remco de Kok, and Conor A. Nixon. "Dynamical implications of seasonal and spatial variations in Titan's stratospheric composition." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 367, no. 1889 (November 20, 2008): 697–711. http://dx.doi.org/10.1098/rsta.2008.0164.

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Titan's diverse inventory of photochemically produced gases can be used as tracers to probe atmospheric circulation. Since the arrival of the Cassini–Huygens mission in July 2004 it has been possible to map the seasonal and spatial variations of these compounds in great detail. Here, we use 3.5 years of data measured by the Cassini Composite InfraRed Spectrometer instrument to determine spatial and seasonal composition trends, thus providing clues to underlying atmospheric motions. Titan's North Pole (currently in winter) displays enrichment of trace species, implying subsidence is occurring there. This is consistent with the descending branch of a single south-to-north stratospheric circulation cell and a polar vortex. Lack of enrichment in the south over most of the observed time period argues against the presence of any secondary circulation cell in the Southern Polar stratosphere. However, a residual cap of enriched gas was observed over the South Pole early in the mission, which has since completely dissipated. This cap was most probably due to residual build-up from southern winter. These observations provide new and important constraints for models of atmospheric photochemistry and circulation.

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Ehrenfreund, P., J. J. Boon, J. Commandeur, C. Sagan, W. R. Thompson, and B. Khare. "Analytical pyrolysis experiments of Titan aerosol analogues in preparation for the Cassini Huygens mission." Advances in Space Research 15, no. 3 (March 1995): 335–42. http://dx.doi.org/10.1016/s0273-1177(99)80105-7.

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Coustenis, A., D. E. Jennings, C. A. Nixon, R. K. Achterberg, P. Lavvas, S. Vinatier, N. A. Teanby, et al. "Titan trace gaseous composition from CIRS at the end of the Cassini–Huygens prime mission." Icarus 207, no. 1 (May 2010): 461–76. http://dx.doi.org/10.1016/j.icarus.2009.11.027.

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25

Griffith, Caitlin Ann. "Storms, polar deposits and the methane cycle in Titan's atmosphere." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 367, no. 1889 (November 21, 2008): 713–28. http://dx.doi.org/10.1098/rsta.2008.0245.

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In Titan's atmosphere, the second most abundant constituent, methane, exists as a gas, liquid and solid, and cycles between the atmosphere and the surface. Similar to the Earth's hydrological cycle, Titan sports clouds, rain and lakes. Yet, Titan's cycle differs dramatically from its terrestrial counterpart, and reveals the workings of weather in an atmosphere that is 10 times thicker than the Earth's atmosphere, that is two orders of magnitude less illuminated, and that involves a different condensable. While ongoing measurements by the Cassini–Huygens mission are revealing the intricacies of the moon's weather, circulation, lake coverage and geology, knowledge is still limited by the paucity of observations. This review of Titan's methane cycle therefore focuses on measured characteristics of the lower atmosphere and surface that appear particularly perplexing or alien.

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Perrot, Bruno, and Roberto Giordani. "Cassini Huygens mission : the exploration of the Saturn system. Radio science experiments : Radio Frequency Instrument Subsystem." Planetary and Space Science 46, no. 9-10 (October 1998): 1333–38. http://dx.doi.org/10.1016/s0032-0633(97)00212-2.

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Lunine, Jonathan I. "Chemistry of the Solar System Revealed in the Interiors of the Giant Planets." Proceedings of the International Astronomical Union 7, S280 (June 2011): 249–60. http://dx.doi.org/10.1017/s1743921311025026.

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AbstractThe giant planets of our solar system contain a record of elemental and isotopic ratios of keen interest for what they tell us about the origin of the planets and in particular the volatile compositions of the solid phases. In situ measurements of the Jovian atmosphere performed by the Galileo Probe during its descent in 1995 demonstrate the unique value of such a record, but limited currently by the unknown abundance of oxygen in the interior of Jupiter–a gap planned to be filled by the Juno mission set to arrive at Jupiter in July of 2016. Our lack of knowledge of the oxygen abundance allows for a number of models for the Jovian interior with a range of C/O ratios. The implications for the origin of terrestrial water are briefly discussed. The complementary data sets for Saturn may be obtained by a series of very close, nearly polar orbits, at the end of the Cassini-Huygens mission in 2016-2017, and the proposed Saturn Probe. This set can only obtain what we have for Jupiter if the Saturn Probe mission carries a microwave radiometer.

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Dandouras, Iannis, Philippe Garnier, Donald G. Mitchell, Edmond C. Roelof, Pontus C. Brandt, Norbert Krupp, and Stamatios M. Krimigis. "Titan's exosphere and its interaction with Saturn's magnetosphere." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 367, no. 1889 (November 20, 2008): 743–52. http://dx.doi.org/10.1098/rsta.2008.0249.

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Titan's nitrogen-rich atmosphere is directly bombarded by energetic ions, due to its lack of a significant intrinsic magnetic field. Singly charged energetic ions from Saturn's magnetosphere undergo charge-exchange collisions with neutral atoms in Titan's upper atmosphere, or exosphere, being transformed into energetic neutral atoms (ENAs). The ion and neutral camera, one of the three sensors that comprise the magnetosphere imaging instrument (MIMI) on the Cassini/Huygens mission to Saturn and Titan, images these ENAs like photons, and measures their fluxes and energies. These remote-sensing measurements, combined with the in situ measurements performed in the upper thermosphere and in the exosphere by the ion and neutral mass spectrometer instrument, provide a powerful diagnostic of Titan's exosphere and its interaction with the Kronian magnetosphere. These observations are analysed and some of the exospheric features they reveal are modelled.

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29

Gautier, Daniel. "Prebiotics on Titan: from Available to Expected Measurements." International Astronomical Union Colloquium 161 (January 1997): 219–26. http://dx.doi.org/10.1017/s0252921100014731.

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AbstractAn intense organic chemistry occurs in the atmosphere of Titan. The detected species are far to be uniformly spatially distributed. Their mixing ratios vary with altitude and latitude. Tentatives to interpret these data are examined. Available photochemical models are discussed and shown to fail to reproduce simultaneously hydrocarbons and nitriles observed abundances., whatever the assumed eddy diffusion coefficient profile. Future models will have to explicitly take into account polymerisation, distributions of aerosols, seasonal effects and atmospheric circulation. The Cassini-Huygens mission, to be launched towards Saturn and Titan in 1997, will provide a tremendous information on the atmospheric composition of organics and on the mapping of the most abundant species. The nature of the aerosols will be investigated. Current theories on the chemical composition of the subnebulae of Saturn in which Titan was formed are discussed. We conclude that billions of like- Titan objects may exist in the Universe.

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Raulin, F., L. Do, C. Frère, and G. Israel. "GC-MS and ACP experiments on the huygens Titan's probe : Possible exobiological implications of the Cassini mission." Origins of Life and Evolution of the Biosphere 19, no. 3-5 (May 1989): 497–98. http://dx.doi.org/10.1007/bf02388970.

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Du, Siliang, Mi Wang, Xiao Chen, Shenghui Fang, and Hongbo Su. "A High-accuracy Extraction Algorithm of Planet Centroid Image in Deep-space Autonomous Optical Navigation." Journal of Navigation 69, no. 4 (December 23, 2015): 828–44. http://dx.doi.org/10.1017/s0373463315000910.

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A planet centroid is an important observable object in autonomous optical navigation. A high-accuracy algorithm is presented to extract the planet centroid from its raw image. First, we proposed a planet segmentation algorithm to segment the planet image block to eliminate noise and to reduce the computation load. Second, we developed an effective algorithm based on Prewitt-Zernike moments to detect sub-pixel real edges by determining possible edges with the Prewitt operator, removing pseudo-edges in backlit shady areas, and relocating real edges to a sub-pixel accuracy in the Zernike moments. Third, we proposed an elliptical model to fit sub-pixel edge points. Finally, we verified the performance of this algorithm against real images from the Cassini-Huygens mission and against synthetic simulated images. Simulation results showed that the accuracy of the planet centroid is up to 0·3 pixels and that of the line-of-sight vector is at 2·1 × 10−5rad.

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di Stefano, Ivan, Daniele Durante, Paolo Cappuccio, and Paolo Racioppa. "Radio Science Experiments during a Cruise Phase to Uranus." Aerospace 11, no. 4 (April 5, 2024): 282. http://dx.doi.org/10.3390/aerospace11040282.

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The exploration of Uranus, a key archetype for ice giant planets and a gateway to understanding distant exoplanets, is acquiring increasing interest in recent years, especially after the Uranus Orbiter and Probe (UOP) mission has been prioritized in the Planetary Science Decadal Survey 2023–2032. This paper presents the results of numerical simulations aimed at providing experimental constraints on the parameterized post-Newtonian (PPN) parameter γ, a measure of space–time curvature in general relativity (GR), during the cruise phase of a spacecraft travelling to Uranus. Leveraging advanced radio tracking systems akin to those aboard the JUICE and BepiColombo missions, we explore the potential of solar conjunction experiments (SCEs) to refine current measurements of γ by exploiting the spacecraft’s long journey in the outer Solar System. We discuss the anticipated enhancements over previous estimates, underscoring the prospect of detecting violations of GR. Our simulations predict that by using an advanced radio tracking system, it is possible to obtain an improvement in the estimation of γ up to more than an order of magnitude with respect to the latest measurement performed by the Cassini–Huygens mission in 2002, contingent on the calibration capabilities against solar plasma noise. The results reveal that a number of SCEs during the mission can substantially strengthen the validation of GR. In tandem with fundamental physics tests, the use of radio links during SCEs presents a valuable opportunity to dissect the solar corona’s plasma dynamics, contributing to solar physics and space weather forecasting. This paper also enumerates methodologies to analyze electron density, localize plasma features, and deduce solar wind velocity, enriching the scientific yield of the experiments beyond the primary objective of testing GR during the cruise phase of a mission to Uranus.

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Rossignoli, N. L., R. P. Di Sisto, M. Zanardi, and A. Dugaro. "Cratering and age of the small Saturnian satellites." Astronomy & Astrophysics 627 (June 25, 2019): A12. http://dx.doi.org/10.1051/0004-6361/201834660.

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Context. The small (≤135 km mean radius) satellites of Saturn are closely related to its rings and together they constitute a complex dynamical system where formation and destruction mechanisms compete against each other. The Cassini-Huygens mission provided high-resolution images of the surfaces of these satellites and therefore allowed for the calculation of observational crater counts. Aims. We model the cratering process by Centaur objects on the small Saturnian satellites, and compare our results with the observational crater counts obtained from the Voyager and Cassini missions. Methods. Using a theoretical model previously developed we calculate the crater production on these satellites considering two slopes of the size-frequency distribution (SFD) for the smaller objects of the Centaur population and compare our results with the available observations. In addition, we consider the case of catastrophic collisions between these satellites and Centaur objects and calculate the age of formation of those satellites that suffer one or more disruptions. Results. In general we find that the observed crater distributions are best modeled by the crater size distribution corresponding to the s2 = 3.5 index of the SFD of impactors with diameters smaller than 60 km. However, for crater diameters D ≲ 3–8 km (which correspond to impactor diameters d ~ 0.04–0.15 km), the observed distributions become flatter and deviate from our results, which may evidence processes of erosion and/or crater saturation at small crater sizes or a possible break in the SFD of impactors at d ~ 0.04–0.15 km to a much shallower differential slope of approximately − 1.5. Our results suggest that Pan, Daphnis, Atlas, Aegaeon, Methone, Anthe, Pallene, Calypso, and Polydeuces suffered one or more catastrophic collisions over the age of the solar system, the younger being associated to arcs with ages of ~108 yr. We have also calculated surface ages for the satellites, which indicate ongoing resurfacing processes.

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Ruffino, G., A. Castelli, P. Coppa, C. Cornaro, S. Foglietta, M. Fulchignoni, F. Gori, and P. Salvini. "The temperature sensor on the Huygens probe for the Cassini mission: design, manufacture, calibration and tests of the laboratory prototype." Planetary and Space Science 44, no. 10 (October 1996): 1149–62. http://dx.doi.org/10.1016/s0032-0633(96)00028-1.

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35

Tokano, Tetsuya. "The dynamics of Titan's troposphere." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 367, no. 1889 (November 19, 2008): 633–48. http://dx.doi.org/10.1098/rsta.2008.0163.

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While the Voyager mission could essentially not reveal the dynamics of Titan's troposphere, useful information was obtained by the Cassini spacecraft and, particularly, by the Huygens probe that landed on Titan's surface; this information can be interpreted by means of numerical models of atmospheric circulation. The meridional circulation is likely to consist of a large Hadley circulation asymmetric about the equator, but is susceptible to disruption by turbulence in clouds. The zonal wind in the troposphere is comparable to or even weaker than that in the terrestrial troposphere and contains zones of easterlies, much in contrast to the super-rotating stratosphere. Unique to Titan is the transition from a geostrophic to cyclostrophic wind balance in the upper troposphere. While Earth-like storm systems associated with baroclinic instability are absent, Saturn's gravitational tide introduces a planetary wave of wavenumber 2 and a periodical variation in the wind direction in the troposphere. Unlike on Earth, the wind over the equatorial surface is westerly. The seasonal reversal in the Hadley circulation sense and zonal wind direction is predicted to have a substantial influence on the formation of dunes as well as variation of Titan's rotation rate and length of day.

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Es-sayeh, M., S. Rodriguez, M. Coutelier, P. Rannou, B. Bézard, L. Maltagliati, T. Cornet, et al. "Updated Radiative Transfer Model for Titan in the Near-infrared Wavelength Range: Validation against Huygens Atmospheric and Surface Measurements and Application to the Cassini/VIMS Observations of the Dragonfly Landing Area." Planetary Science Journal 4, no. 3 (March 1, 2023): 44. http://dx.doi.org/10.3847/psj/acbd37.

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Abstract We present an analysis of Titan data acquired by the Cassini Visual and Infrared Mapping Spectrometer (VIMS) at the landing site of the Dragonfly mission, using a new version of our radiative transfer model for Titan, with significant updates for the spectroscopic parameters of atmospheric gases and photochemical aerosols. Our updated radiative transfer model is validated against the in situ spectroscopic measurements of the Huygens probe during its descent and once landed. We confirm that aerosols with a fractal dimension of 2.3–2.4 provide the best fit to the observations. We apply our radiative transfer model to four VIMS data cubes over the Selk crater region including the Dragonfly landing and exploration areas, further validating our model by producing consistent aerosol population and surface albedo maps. These infrared albedo maps, further corrected from the photometry, enable us to study the Selk crater region in terms of surface composition, landscape formation, and evolution. Our results suggest that the Selk crater is in an intermediate state of degradation and that the mountainous terrains of the area (including the crater rim and ejecta) are likely to be dominated by fine grains of tholin-like sediment. This organic sediment would be transported to the lowlands (crater floor and surrounding plains), possibly with water ice particles, by rivers, and further deposited and processed to form the sand particles that feed the neighboring dune fields. These results provide information for the operational and scientific preparation of the Dragonfly mission, paving the way for future exploration of Titan’s surface composition and geology.

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Rahm, Martin, Jonathan I. Lunine, David A. Usher, and David Shalloway. "Polymorphism and electronic structure of polyimine and its potential significance for prebiotic chemistry on Titan." Proceedings of the National Academy of Sciences 113, no. 29 (July 5, 2016): 8121–26. http://dx.doi.org/10.1073/pnas.1606634113.

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The chemistry of hydrogen cyanide (HCN) is believed to be central to the origin of life question. Contradictions between Cassini–Huygens mission measurements of the atmosphere and the surface of Saturn’s moon Titan suggest that HCN-based polymers may have formed on the surface from products of atmospheric chemistry. This makes Titan a valuable “natural laboratory” for exploring potential nonterrestrial forms of prebiotic chemistry. We have used theoretical calculations to investigate the chain conformations of polyimine (pI), a polymer identified as one major component of polymerized HCN in laboratory experiments. Thanks to its flexible backbone, the polymer can exist in several different polymorphs, which are relatively close in energy. The electronic and structural variability among them is extraordinary. The band gap changes over a 3-eV range when moving from a planar sheet-like structure to increasingly coiled conformations. The primary photon absorption is predicted to occur in a window of relative transparency in Titan’s atmosphere, indicating that pI could be photochemically active and drive chemistry on the surface. The thermodynamics for adding and removing HCN from pI under Titan conditions suggests that such dynamics is plausible, provided that catalysis or photochemistry is available to sufficiently lower reaction barriers. We speculate that the directionality of pI’s intermolecular and intramolecular =N–H…N hydrogen bonds may drive the formation of partially ordered structures, some of which may synergize with photon absorption and act catalytically. Future detailed studies on proposed mechanisms and the solubility and density of the polymers will aid in the design of future missions to Titan.

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Pogrebenko, Sergei V., Leonid I. Gurvits, Moshe Elitzur, Cristiano B. Cosmovici, Ian M. Avruch, Salvatore Pluchino, Stelio Montebugnoli, et al. "Water masers in the Kronian system." Proceedings of the International Astronomical Union 5, S263 (August 2009): 147–50. http://dx.doi.org/10.1017/s1743921310001663.

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AbstractThe presence of water has been considered for a long time as a key condition for life in planetary environments. The Cassini mission discovered water vapour in the Kronian system by detecting absorption of UV emission from a background star (Hansen et al. 2006). Prompted by this discovery, we started an observational campaign for search of another manifestation of the water vapour in the Kronian system, its maser emission at the frequency of 22 GHz (1.35 cm wavelength). Observations with the 32 m Medicina radio telescope (INAF-IRA, Italy) started in 2006 using Mk5A data recording and the JIVE-Huygens software correlator. Later on, an on-line spectrometer was used at Medicina. The 14 m Metsähovi radio telescope (TKK-MRO, Finland) joined the observational campaign in 2008 using a locally developed data capture unit and software spectrometer. More than 300 hours of observations were collected in 2006-2008 campaign with the two radio telescopes. The data were analysed at JIVE using the Doppler tracking technique to compensate the observed spectra for the radial Doppler shift for various bodies in the Kronian system (Pogrebenko et al. 2009). Here we report the observational results for Hyperion, Titan, Enceladus and Atlas, and their physical interpretation. Encouraged by these results we started a campaign of follow up observations including other radio telescopes.

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Tadeu Ceccatto, Demétrio, Nelson Callegari, and Adrián Rodríguez. "The current orbit of Atlas (SXV)." Proceedings of the International Astronomical Union 15, S364 (October 2021): 120–27. http://dx.doi.org/10.1017/s1743921321001319.

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AbstractWith the success of the Cassini-Huygens mission, the dynamic complexity surrounding natural satellites of Saturn began to be elucidated. New ephemeris could be calculated with a higher level of precision, which made it possible to study in detail the resonant phenomena and, in particular, the 54:53 near mean-motion resonance between Prometheus and Atlas. For this task, we have mapped in details the domains of the resonance with dense sets of initial conditions and distinct ranges of parameters. Our initial goal was to identify possible regions in the phase space of Atlas for which some critical angles, associated with the 54:53 mean motion have a stable libration. Our investigations revealed that there is no possibility for the current Atlas orbital configuration to have any regular behavior since it is in a chaotic region located at the boundary of the 54:53 mean-motion resonance phase space. This result is in accordance with previous works (Cooper et al. 2015; Renner et al. 2016). In this work, we generalize such investigations by showing detailed aspects of the Atlas-Prometheus 54:53 mean-motion resonance, like the extension of the chaotic layers, the thin domain of the center of the 54:53 resonance, the proximity of other neighborhood resonances, among other secondary conclusions. In particular, we have also shown that even in the deep interior of the resonance, it is difficult to map periodic motion of the resonant pair for very long time spans.

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Noyelles, Benoît, and Francis Nimmo. "New clues on the interior of Titan from its rotation state." Proceedings of the International Astronomical Union 9, S310 (July 2014): 17–20. http://dx.doi.org/10.1017/s1743921314007728.

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AbstractThe Saturnian satellite Titan is one of the main targets of the Cassini-Huygens mission, which revealed in particular Titan's shape, gravity field, and rotation state. The shape and gravity field suggest that Titan is not in hydrostatic equilibrium, that it has a global subsurface ocean, and that its ice shell is both rigid (at tidal periods) and of variable thickness. The rotational state of Titan consists of an expected synchronous rotation rate and an unexpectedly high obliquity (0.3○) explained by Baland et al. (2011) to be a resonant behavior. We here combine a realistic model of the ice shell and interior and a 6-degrees of freedom rotational model, in which the librations, obliquity and polar motion of the rigid core and of the shell are modelled, to constrain the structure of Titan from the observations. We consider the gravitational pull of Saturn on the 2 rigid layers, the gravitational coupling between them, and the pressure coupling at the liquid-solid interfaces.We confirm the influence of the resonance found by Baland et al., that affects between 10 and 13% of the possible Titans. It is due to the 29.5-year periodic annual forcing. The resonant Titans can be obtained in situations in which a mass anomaly at the shell-ocean boundary (bottom loading) is from 80 to 92% compensated. This suggests a 250 to 280 km thick ocean below a 130 to 140 km thick shell, and is consistent with the degree-3 analysis of Hemingway 26 et al. (2013).

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Owen, Tobias. "The Contributions of Comets to Planets, Atmospheres, and Life: Insights from Cassini-Huygens, Galileo, Giotto, and Inner Planet Missions." Space Science Reviews 138, no. 1-4 (January 31, 2008): 301–16. http://dx.doi.org/10.1007/s11214-008-9306-7.

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"Cassini-Huygens Saturn mission ends spectacularly." Physics Teacher 55, no. 8 (November 2017): 509. http://dx.doi.org/10.1119/1.5008358.

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Sulaiman, Ali H., Nicholas Achilleos, Cesar Bertucci, Andrew Coates, Michele Dougherty, Lina Hadid, Mika Holmberg, et al. "Enceladus and Titan: emerging worlds of the Solar System." Experimental Astronomy, December 1, 2021. http://dx.doi.org/10.1007/s10686-021-09810-z.

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AbstractSome of the major discoveries of the recent Cassini-Huygens mission have put Titan and Enceladus firmly on the Solar System map. The mission has revolutionised our view of Solar System satellites, arguably matching their scientific importance with that of their host planet. While Cassini-Huygens has made big surprises in revealing Titan’s organically rich environment and Enceladus’ cryovolcanism, the mission’s success naturally leads us to further probe these findings. We advocate the acknowledgement of Titan and Enceladus science as highly relevant to ESA’s long-term roadmap, as logical follow-on to Cassini-Huygens. In this White Paper, we will outline important science questions regarding these satellites and identify the science themes we recommend ESA cover during the Voyage 2050 planning cycle. Addressing these science themes would make major advancements to the present knowledge we have about the Solar System, its formation, evolution, and likelihood that other habitable environments exist outside the Earth’s biosphere.

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Lunn, Jenny, Mike Liemohn, Mark Moldwin, and Elizabeth Turtle. "Cassini’s Legacy in Print." Eos 98 (September 20, 2017). http://dx.doi.org/10.1029/2018eo082295.

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Mitri, Giuseppe, Jason Barnes, Athena Coustenis, Enrico Flamini, Alexander Hayes, Ralph D. Lorenz, Marco Mastrogiuseppe, et al. "Exploration of Enceladus and Titan: investigating ocean worlds’ evolution and habitability in the Saturn system." Experimental Astronomy, July 22, 2021. http://dx.doi.org/10.1007/s10686-021-09772-2.

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AbstractWe present a White Paper with a science theme concept of ocean world evolution and habitability proposed in response to ESA’s Voyage 2050 Call with a focus on Titan and Enceladus in the Saturn system. Ocean worlds in the outer Solar System that possess subsurface liquid water oceans are considered to be prime targets for extra-terrestrial life and offer windows into Solar System evolution and habitability. The Cassini-Huygens mission to the Saturn system (2004–2017) revealed Titan with its organic-rich evolving world with terrestrial features and Enceladus with its active aqueous environment to be ideal candidates to investigate ocean world evolution and habitability. Additionally, this White Paper presents a baseline for a multiple flyby mission with a focused payload as an example of how ocean world evolution and habitability in the Saturn system could be investigated building on the heritage of the Cassini-Huygens mission and complementing the recently selected NASA Dragonfly mission.

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"Mission to Saturn: Cassini and the Huygens probe." Choice Reviews Online 40, no. 09 (May 1, 2003): 40–5208. http://dx.doi.org/10.5860/choice.40-5208.

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Wendel, JoAnna. "Saturn Unveiled: Ten Notable Findings from Cassini-Huygens." Eos, July 19, 2017. http://dx.doi.org/10.1029/2017eo077957.

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Sotin, Christophe, Klára Kalousová, and Gabriel Tobie. "Titan's Interior Structure and Dynamics After the Cassini-Huygens Mission." Annual Review of Earth and Planetary Sciences 49, no. 1 (March 22, 2021). http://dx.doi.org/10.1146/annurev-earth-072920-052847.

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The Cassini-Huygens mission that explored the Saturn system during the period 2004–2017 revolutionized our understanding of Titan, the only known moon with a dense atmosphere and the only body, besides Earth, with stable surface liquids. Its predominantly nitrogen atmosphere also contains a few percent of methane that is photolyzed on short geological timescales to form ethane and more complex organic molecules. The presence of a significant amount of methane and 40Ar, the decay product of 40K, argues for exchange processes from the interior to the surface. Here we review the information that constrains Titan's interior structure. Gravity and orbital data suggest that Titan is an ocean world, which implies differentiation into a hydrosphere and a rocky core. The mass and gravity data complemented by equations of state constrain the ocean density and composition as well as the hydrosphere thickness. We present end-member models, review the dynamics of each layer, and discuss the global evolution consistent with the Cassini-Huygens data. ▪ Titan is the only moon with a dense atmosphere where organic molecules are synthesized and have sedimented at the surface. ▪ The Cassini-Huygens mission demonstrated that Titan is an ocean world with an internal water shell and liquid hydrocarbon seas at the poles. ▪ Interactions between water, rock, and organics may have occurred during most of Titan's evolution, which has strong astrobiological implications. ▪ Data collected by the Dragonfly mission and comparison with the JUpiter ICy moons Explorer (JUICE) data for Ganymede will further reveal Titan's astrobiology potential. Expected final online publication date for the Annual Review of Earth and Planetary Sciences, Volume 49 is May 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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Zuppardi, Gennaro, and Giuseppe Mongelluzzo. "Aerodynamic Analysis of an Entry Capsule at Titan in Transition Regime." Journal of Spacecraft and Rockets, January 1, 2023, 1–9. http://dx.doi.org/10.2514/1.a35407.

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The interest of the scientific community in Titan, Saturn’s largest moon, is still strong. In fact, after the successful Cassini–Huygens mission, which landed the Huygens capsule on Titan, other missions are planned in the coming years. The aims of this work are to provide the extent of global aerodynamic force, to provide thermal and aerodynamic loads on a capsule entering Titan atmosphere, and to evaluate the effects of chemistry on 1) flowfield parameters, 2) surface catalyticity, 3) temperature and pressure distributions on a heat shield, and 4) global aerodynamic force. To develop this study, the authors used the Huygens capsule and related entry trajectory. The study was carried out in the altitude interval of 295–470 km by means of the direct simulation Monte Carlo codes: DS2V for the solution of two-dimensional/axisymmetric flowfields, and DS3V for the solution of three-dimensional flowfields. The Titan atmosphere is a mixture of nitrogen, methane, and argon. The chemical model is made of 221 reactions, making gas around the capsule a mixture of 18 species. Chemistry strongly influences local aerodynamic quantities, both in the flowfield and on the capsule surface; whereas the chemical effects on the global aerodynamic force are negligible. Our computations also verified the lack of ionization.

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Rodriguez, Sébastien, Sandrine Vinatier, Daniel Cordier, Gabriel Tobie, Richard K. Achterberg, Carrie M. Anderson, Sarah V. Badman, et al. "Science goals and new mission concepts for future exploration of Titan’s atmosphere, geology and habitability: titan POlar scout/orbitEr and in situ lake lander and DrONe explorer (POSEIDON)." Experimental Astronomy, January 11, 2022. http://dx.doi.org/10.1007/s10686-021-09815-8.

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AbstractIn response to ESA’s “Voyage 2050” announcement of opportunity, we propose an ambitious L-class mission to explore one of the most exciting bodies in the Solar System, Saturn’s largest moon Titan. Titan, a “world with two oceans”, is an organic-rich body with interior-surface-atmosphere interactions that are comparable in complexity to the Earth. Titan is also one of the few places in the Solar System with habitability potential. Titan’s remarkable nature was only partly revealed by the Cassini-Huygens mission and still holds mysteries requiring a complete exploration using a variety of vehicles and instruments. The proposed mission concept POSEIDON (Titan POlar Scout/orbitEr and In situ lake lander DrONe explorer) would perform joint orbital and in situ investigations of Titan. It is designed to build on and exceed the scope and scientific/technological accomplishments of Cassini-Huygens, exploring Titan in ways that were not previously possible, in particular through full close-up and in situ coverage over long periods of time. In the proposed mission architecture, POSEIDON consists of two major elements: a spacecraft with a large set of instruments that would orbit Titan, preferably in a low-eccentricity polar orbit, and a suite of in situ investigation components, i.e. a lake lander, a “heavy” drone (possibly amphibious) and/or a fleet of mini-drones, dedicated to the exploration of the polar regions. The ideal arrival time at Titan would be slightly before the next northern Spring equinox (2039), as equinoxes are the most active periods to monitor still largely unknown atmospheric and surface seasonal changes. The exploration of Titan’s northern latitudes with an orbiter and in situ element(s) would be highly complementary in terms of timing (with possible mission timing overlap), locations, and science goals with the upcoming NASA New Frontiers Dragonfly mission that will provide in situ exploration of Titan’s equatorial regions, in the mid-2030s.

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Journal articles on the topic 'Mission Cassini-Huygens'

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