E. P. Turtle
A5007615360- Astro and Planetary Science
- Planetary Science and Exploration
- Space Exploration and Technology
- Geology and Paleoclimatology Research
- Isotope Analysis in Ecology
- Spacecraft and Cryogenic Technologies
- Solar and Space Plasma Dynamics
- Geomagnetism and Paleomagnetism Studies
- Methane Hydrates and Related Phenomena
- Marine and environmental studies
- Geological and Geochemical Analysis
- Stellar, planetary, and galactic studies
- Spacecraft Design and Technology
- Space Satellite Systems and Control
- Spaceflight effects on biology
- Aeolian processes and effects
- earthquake and tectonic studies
- Space Science and Extraterrestrial Life
- Astrophysics and Star Formation Studies
- Scientific Research and Discoveries
- Nuclear Physics and Applications
- High-pressure geophysics and materials
- Geophysics and Gravity Measurements
- Technology Assessment and Management
- Ionosphere and magnetosphere dynamics
Johns Hopkins University Applied Physics Laboratory
2015-2024
Johns Hopkins University
2006-2021
Cornell University
2005-2021
Jet Propulsion Laboratory
2004-2021
Technische Universität Dresden
2021
Centre National de la Recherche Scientifique
2005-2021
Imperial Valley College
2021
Georgia Institute of Technology
2021
Flinders Medical Centre
2021
University of Washington
2021
Cassini has identified a geologically active province at the south pole of Saturn's moon Enceladus. In images acquired by Imaging Science Subsystem (ISS), this region is circumscribed chain folded ridges and troughs approximately 55 degrees S latitude. The terrain southward boundary distinguished its albedo color contrasts, elevated temperatures, extreme geologic youth, narrow tectonic rifts that exhibit coarse-grained ice coincide with hottest temperatures measured in region. Jets fine icy...
It has been proposed that Jupiter's satellite Europa currently possesses a global subsurface ocean of liquid water. Galileo gravity data verify the is differentiated into an outer H 2 O layer about 100 km thick but cannot determine current physical state this (liquid or solid). Here we summarize geological evidence regarding extant ocean, concentrating on imaging data. We describe and assess nine pertinent lines evidence: impact morphologies, lenticulae, cryovolcanic features, pull‐apart...
Abstract NASA’s Dragonfly mission will send a rotorcraft lander to the surface of Titan in mid-2030s. Dragonfly's science themes include investigation Titan’s prebiotic chemistry, habitability, and potential chemical biosignatures from both water-based “life as we know it” (as might occur interior mantle ocean, cryovolcanic flows, and/or impact melt deposits) “life, but not that use liquid hydrocarbons solvent (within lakes, seas, aquifers). Consideration these solvents simultaneously led...
Abstract The goal of NASA’s Europa Clipper mission is to assess the habitability Jupiter’s moon Europa. After entering Jupiter orbit in 2030, flight system will collect science data while flying past 49 times at typical closest approach distances 25–100 km. mission’s objectives are investigate Europa’s interior (ice shell and ocean), composition, geology; also search for characterize any current activity including possible plumes. be accomplished with a payload consisting remote sensing...
Images acquired of Saturn's rings and small moons by the Cassini Imaging Science Subsystem (ISS) during first 9 months operations at Saturn have produced many new findings. These include saturnian moons; refined orbits previously known narrow diffuse in F-ring region embedded gaps within main rings; exceptionally fine-scale ring structure moderate- to high-optical depth regions; estimates for masses ring-region moons, as well particle properties division, derived from analysis linear density...
Although there is evidence that liquids have flowed on the surface at Titan's equator in past, to date, only been confirmed polar latitudes, and vast expanses of dunes dominate equatorial regions require a predominantly arid climate. We report detection by Cassini's Imaging Science Subsystem large low-latitude cloud system early northern spring extensive changes (spanning more than 500,000 square kilometers) wake this storm. The are most consistent with widespread methane rainfall reaching...
Cassini's Imaging Science Subsystem (ISS) has been observing Titan since April 2004, compiling a nearly global surface map and monitoring the atmosphere for activity. Early images of south‐polar region revealed numerous dark features contemporaneous convective cloud systems, suggesting presence hydrocarbon lakes similar to those later detected at Titan's North Pole. Intriguingly, repeated imaging by ISS differences consistent with ponding liquids on due precipitation from large storm. More...
The Cassini Imaging Science Subsystem acquired high-resolution imaging data on the outer Saturnian moon, Phoebe, during Cassini's close flyby 11 June 2004 and Iapetus a 31 December 2004. Phoebe has heavily cratered ancient surface, shows evidence of ice near distinct layering different materials, mean density that is indicative an ice-rock mixture. Iapetus's dark leading side (Cassini Regio) ancient, terrain bisected by equatorial ridge system reaches 20 kilometers relief. Local albedo...
Lunar Lobate Scarps Revealed lobate scarps are relatively small-scale landforms that thought to be formed by tectonic thrust faulting. Previously, lunar could only identified clearly in high-resolution Apollo Panoramic Camera images confined the equatorial zone. Now, an analysis Watters et al. (p. 936 ) of returned Reconnaissance Orbiter reveals 14 previously unknown and shows may globally distributed. Their appearance suggests young (less than 1 Ga), possibly during a recent episode global...
Abstract The factors contributing to the initial selection of a dune site near Selk impact structure on Titan as first landing for Dragonfly mission are described. These include arrival geometry and aerodynamic/aerothermodynamic considerations, illumination, Earth visibility, well likely presence exposed deposits water-rich material, potentially including materials where molten ice has interacted with organics. Cassini observations summarized interpreted: near-infrared reflectance microwave...
Several impact craters on Jupiter's satellite Europa exhibit central peaks. On the terrestrial planets, peaks consist of fractured but competent rock uplifted during cratering. Therefore, observation indicates that an ice layer must be sufficiently thick events did not completely penetrate it. We conducted numerical simulations vapor and melt production cratering water layers overlying liquid to estimate thickness Europa's icy crust. Because impacts disrupt material well beyond zone partial...
The Cassini Imaging Science Subsystem (ISS) began observing Saturn in early February 2004. From analysis of cloud motions through October 2004, we report vertical wind shear Saturn's equatorial jet and a maximum speed â¼375 meters per second, value that differs from both Hubble Space Telescope Voyager values. We also particularly active narrow southern mid-latitude region which dark ovals are observed to merge with each other arise the eruptions large, bright storms. Bright storm correlated...
[1] The Cassini Imaging Science Subsystem has observed Titan for ∼1/4 year, and we report here the first evidence of seasonal shifts in preferred locations tropospheric methane clouds. South-polar convective cloud activity, common late southern summer, become rare. North-polar northern mid-latitude clouds appeared during approach to spring equinox August 2009. Recent observations have shown extensive systems at low latitudes. In contrast, subtropical sporadically throughout mission,...
TandEM was proposed as an L-class (large) mission in response to ESA's Cosmic Vision 2015–2025 Call, and accepted for further studies, with the goal of exploring Titan Enceladus. The concept is perform situ investigations two worlds tied together by location properties, whose remarkable natures have been partly revealed ongoing Cassini–Huygens mission. These bodies still hold mysteries requiring a complete exploration using variety vehicles instruments. ambitious because its targets are most...