A5012314096- Astro and Planetary Science
- Planetary Science and Exploration
- Geology and Paleoclimatology Research
- Marine and environmental studies
- Geophysics and Gravity Measurements
- Isotope Analysis in Ecology
- Methane Hydrates and Related Phenomena
- Space Exploration and Technology
- Geomagnetism and Paleomagnetism Studies
- Space Science and Extraterrestrial Life
- Maritime Navigation and Safety
- Geological and Geochemical Analysis
- Maritime and Coastal Archaeology
- earthquake and tectonic studies
- Paleontology and Stratigraphy of Fossils
- Aeolian processes and effects
- Spacecraft and Cryogenic Technologies
- Oceanographic and Atmospheric Processes
- Experimental and Theoretical Physics Studies
- Geochemistry and Geologic Mapping
- Remote Sensing and Land Use
- Remote Sensing in Agriculture
- Journalism and Media Studies
- Cryospheric studies and observations
- Aerospace Engineering and Energy Systems
Cornell University
2017-2024
Planetary Science Institute
2021-2023
Sapienza University of Rome
2011-2016
Abstract We construct the depth profile—the bathymetry—of Titan's large sea Ligeia Mare from Cassini RADAR data collected during 23 May 2013 (T91) nadir‐looking altimetry flyby. find greatest to be about 160 m and a seabed slope that is gentler toward northern shore, consistent with previously imaged shoreline morphologies. Low radio signal attenuation through demonstrates liquid, for which we determine loss tangent of 3 ± 1·10 −5 , remarkably transparent, requiring nearly pure...
Abstract With the conclusion of Cassini mission, we present an updated topographic map Titan, including all available altimetry, SARtopo, and stereophotogrammetry data sets from mission. We use radial basis functions to interpolate sparse set, which covers only ∼9% Titan's global area. The most notable updates topography include higher coverage poles improved fits shape, a finer resolution interpolation. also statistical analysis error in derived products perform minimization on...
Abstract The topography provided by altimetry, synthetic aperture radar‐topography, and stereo radargrammetry has opened new doors for Titan research allowing quantitative analysis of morphologic form. Using altimetry measurements, we show that Titan's Maria are consistent with an equipotential surface but several filled lakes found to be hundreds meters above this sea level, suggesting they exist in isolated or perched basins. Within a given drainage basin, empty lake floors typically...
Abstract In May 2013 the Cassini RADAR altimeter observed channels in Vid Flumina, a drainage network connected to Titan's second largest hydrocarbon sea, Ligeia Mare. Analysis of these echoes shows that are located deep (up ~570 m), steep‐sided, canyons and have strong specular surface reflections indicate they currently liquid filled. Elevations at same level as Mare within vertical precision about 0.7 m, consistent with interpretation drowned river valleys. Specular also lower order...
Recently, the Cassini RADAR has been used as a sounder to probe depth and constrain composition of hydrocarbon seas on Saturn's largest moon, Titan. Altimetry waveforms from observations over are generally composed two main reflections: first surface liquid second seafloor. The time interval between these peaks is measure sea depth, attenuation propagation through dielectric properties, which sensitive property composition. Radar measurements affected by uncertainties that can include...
Abstract Saturn’s moon Titan was explored by the Cassini spacecraft from 2004 to 2017. While revealed a lot about this Earth-like world, its radar observations could only provide limited information Titan’s liquid hydrocarbons seas Kraken, Ligeia and Punga Mare. Here, we show results of analysis mission bistatic experiments data polar seas. The dual-polarized nature allow independent estimates effective relative dielectric constant small-scale roughness sea surface, which were not possible...
During the Cassini Prime (2004-2008) and Equinox (2008-2010) missions, Radio Science Subsystem onboard spacecraft conducted seven bistatic radar (BSR) observations of Titan, Saturn’s largest moon. A variety terrains, including unique geological features such as plains dunes identified by RADAR, were observed across equatorial, mid-latitude, south-polar regions.In this radio science experiment, Cassini’s High-Gain Antenna (HGA) transmitted unmodulated, right-hand...
Abstract Moray Sinus is an estuary located at the northern end of Titan's Kraken Mare. The Cassini RADAR altimeter acquired three segments over this mare during T104 flyby Titan, on August 21, 2014. Herein, we present a detailed analysis received echoes. Some these waveforms exhibit reflection from seafloor, up to m depth (1 σ error). Monte Carlo simulations have been performed in order assess most probable values and estimation errors for seafloor depth. Insights study, featuring synergic...
Abnormally bright radar reflections below the Martian south polar layered deposit were originally interpreted as evidence of subglacial liquid water. However, unlike on Earth, conditions beneath ice are too cold to create or maintain meltwater. In this work, we use reflectivity simulations show that strong can instead be caused by constructive interference between dusty layers more closely spaced than resolution. Unlike previous hypotheses, does not require anomalous subsurface exotic...
Abstract We perform a systematic survey of Titan's sharp‐edged depressions (SEDs) using combination Cassini synthetic aperture radar images and delay‐Doppler processed altimetry. identify characteristic bright‐dark pattern around 172 SEDs that correlates with elevated features only resolved the highest resolution topographic data. find ∼75% have (∼100 m) rim features, preference toward larger SEDs. The differences in distribution SED presence between north south are slight, but data weakly...
Abstract The Selk crater region is the future landing site of NASA’s Dragonfly mission to Titan. was imaged by Cassini RADAR at incidence angles from 5° 72° and various polarization angles. Using this data set, we mapped six terrain units assembled a backscatter curve for each, providing normalized cross section ( σ 0 ) as function angle. By fitting these curves with sum quasi-specular diffuse terms evaluating three alternative formulations first two second, extracted best-fit surface...
The Cassini RADAR altimeter has provided broad-scale surface topography data for Saturn's largest moon Titan. Herein, we adapt the delay/Doppler algorithm to take into account geometries and antenna mispointing usually occurring during hyperbolic Titan flybys. proposed allows up tenfold improvement in along-track resolution. Preliminary results are that show how improved presented herein can advance our understanding of Titan's characteristics.
Recent discoveries of anomalously bright radar reflections below the Mars South Polar Layered Deposit (SPLD) have sparked new speculation that liquid water may be present ice cap. The reflections, discovered in data acquired by Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on board Express orbiter, were interpreted as from damp materials or even subsurface ponds lakes similar to those found beneath Earth's sheets. studies, however, questioned feasibility melting maintaining...
Abstract Evidence for tectonic activity on Titan is provided by the presence of eroded mountain ranges. Xanadu an equatorial region characterized a complex topography, even though, overall, it has lower average elevation compared to its surroundings. We investigated Xanadu's southwestern margin, part composed heavily and rugged terrains north east, smoother, more uniform west south. The central portions (SW Xanadu) are extensive fluvial network. such distinctive feature was main reason...
Widespread longitudinal dunes have been identified on Titan thanks to the 2.2-cm wavelength Cassini Synthetic Aperture Radar (SAR) instrument. Understanding properties of these surface features, such as material composition and dune height, is very important for giving new clues about geology climate. One major difficulties in estimation heights using SAR occurs when heterogeneous. In this paper, we propose a novel method height estimation, which takes into account heterogeneity, particular,...
This work focuses on the retrieval of Titan's dune field characteristics addressing different radar modes. The main purpose proposed is to exploit a possible synergy between SAR and altimeter acquisitions modes provide information about field. Cassini has performed 86 Titan flybys in which several observations fields have been collected altimetry mode. There are cases acquired over same areas covered by fields, such as during T28 (SAR) T30 (altimeter) flybys. Altimetry together with data...