Rajani D. Dhingra
A5081683942- Astro and Planetary Science
- Planetary Science and Exploration
- Geology and Paleoclimatology Research
- Stellar, planetary, and galactic studies
- Space Exploration and Technology
- Isotope Analysis in Ecology
- Marine and environmental studies
- Paleontology and Stratigraphy of Fossils
- Oceanographic and Atmospheric Processes
- Magnetic confinement fusion research
- Geomagnetism and Paleomagnetism Studies
- Geological and Geochemical Analysis
- Adhesion, Friction, and Surface Interactions
- Earthquake Detection and Analysis
- Atomic and Subatomic Physics Research
- earthquake and tectonic studies
- Geological formations and processes
- Surface Modification and Superhydrophobicity
- Geophysics and Gravity Measurements
- Space Science and Extraterrestrial Life
- Landslides and related hazards
- Maritime and Coastal Archaeology
- Fluid Dynamics Simulations and Interactions
- Hydrocarbon exploration and reservoir analysis
- Gamma-ray bursts and supernovae
Jet Propulsion Laboratory
2020-2024
California Institute of Technology
2020-2021
University of Idaho
2017-2020
John Wiley & Sons (United States)
2019
Charles River Laboratories (Netherlands)
2019
Institute for Plasma Research
2013
The Kuiper Belt is a distant region of the Solar System. On 1 January 2019, New Horizons spacecraft flew close to (486958) 2014 MU69, Cold Classical Object, class objects that have never been heated by Sun and are therefore well preserved since their formation. Here we describe initial results from these encounter observations. MU69 bi-lobed contact binary with flattened shape, discrete geological units, noticeable albedo heterogeneity. However, there little surface color compositional No...
The New Horizons spacecraft returned images and compositional data showing that terrains on Pluto span a variety of ages, ranging from relatively ancient, heavily cratered areas to very young surfaces with few-to-no impact craters. One the regions few craters is dominated by enormous rises hummocky flanks. Similar features do not exist anywhere else in imaged solar system. Here we analyze geomorphology composition conclude this region was resurfaced cryovolcanic processes, type scale so far...
The Cold Classical Kuiper Belt, a class of small bodies in undisturbed orbits beyond Neptune, are primitive objects preserving information about Solar System formation. New Horizons spacecraft flew past one these objects, the 36 km long contact binary (486958) Arrokoth (2014 MU69), January 2019. Images from flyby show that has no detectable rings, and satellites (larger than 180 meters diameter) within radius 8000 km, lightly-cratered smooth surface with complex geological features, unlike...
Abstract Methane rain on Saturn's moon Titan makes it the only place, other than Earth, where interacts with surface. When and that wets surface changes seasonally in ways remain poorly understood. Here we report discovery of a bright ephemeral feature covering an area 120,000 km 2 near Titan's north pole observations from Cassini's near‐infrared instrument, Visual Infrared Mapping Spectrometer 7 June 2016. Based overall brightness, spectral characteristics, geologic context, attribute this...
The New Horizons encounter with the cold classical Kuiper Belt object (KBO) 2014 MU69 (informally named 'Ultima Thule,' hereafter Ultima) on 1 January 2019 will be first time a spacecraft has ever closely observed one of free-orbiting small denizens Belt. Related to but not thought have formed in same region Solar System as comets that been explored so far, it also largest, most distant, and primitive body yet visited by spacecraft. In this letter we begin brief overview KBOs, which Ultima...
Abstract We use the elliptical Fourier descriptor analysis (EFDA) to quantify shapes of Titan’s lakes technically demonstrate this methodology in planetary morphometry. map on north pole and find that equivalent radii 224 follow a relatively narrow log-normal distribution like Earth’s thermokarst Io’s volcanic paterae, indicating limited number formation processes. Then, we using EFDA. The decomposes shape lake into multiple series, corresponding coefficients represent fingerprint shape....
Abstract We identify and document the instances of bright ephemeral features (BEF)—bright areas that appear, disappear, shift from flyby to on Titan’s north pole, using Cassini Visual Infrared Mapping Spectrometer data set, thereby developing a sense their spatial distribution temporal frequency. find BEFs have differing geographic location extents. However, they similar observation geometries orders surface area coverage are mostly accompanied by specular reflections. represent either broad...
Core-ion temperature measurements have been carried out by the energy analysis of passive charge exchange (CX) neutrals escaping ADITYA tokamak plasma (minor radius, a = 25 cm and major R 75 cm) using 45° parallel plate electrostatic analyzer. The neutral particle analyzer (NPA) uses gas cell configuration for re-ionizing CX-neutrals channel electron multipliers (CEMs) as detectors. Energy calibration NPA has ion-source ΔE/E high-energy found to be ∼10%. Low signal noise ratio (SNR) due VUV...
As one of two planetary objects (other than Earth) that have solid surfaces, thick atmospheres, and astrobiological significance, Titan, like Mars, merits ongoing study with multiple spacecraft.We propose a Titan orbiter dedicated to geophysics, geology, atmospheric science be added the New Frontiers menu for coming decade.
Ice giants are the only unexplored class of planet in our Solar System. Much that we currently know about these systems challenges understanding how planets, rings, satellites, and magnetospheres form evolve. We assert an ice giant Flagship mission with atmospheric probe should be a priority for decade 2023-2032.
Abstract We report a temperature difference in one of the regions on Titan that is, documented as bright ephemeral feature (BEF). Spectra were recorded by Cassini's Composite Infrared Spectrometer. BEFs are 5 µ m areas appear, disappear, and shift from flyby to at Titan's North Pole observed Visual Mapping Spectrometer (VIMS) data. They inferred be broad‐specular reflections caused smooth surface or near fog—both which indicate atmosphere interacted with surface. used 24 spectra for “on BEF”...
Abstract We present Cassini Visual and Infrared Mapping Spectrometer (VIMS) observations of sun glitter—wave-induced reflections from a liquid surface offset specular point—on Kraken Mare. Sun glitter reveals rough sea surfaces around Mare, namely the coasts narrow straits. The indicate wave activity driven by winds tidal currents in Mare during northern summer. T104 VIMS show three features Bayta Fretum indicative variegated fields. cannot uniquely determine one source for coastal waves,...
Abstract We infer the surface reflectance properties of Europa using multispectral data sets available from previous missions. use 21 full-disk images Voyager’s Imaging Science System, Galileo’s Solid State Imaging, and New Horizons’ Long Range Reconnaissance Imager at differing observation geometries (10°–128° (phase angle)) to compute disk-integrated surface-scattering over various geologic units. The derived empirical photometric models will serve practical goals acquisition, aid in...