J. B. Garvin
A5091120451- Planetary Science and Exploration
- Astro and Planetary Science
- Space Exploration and Technology
- Space Science and Extraterrestrial Life
- Geology and Paleoclimatology Research
- Space exploration and regulation
- Spaceflight effects on biology
- Methane Hydrates and Related Phenomena
- Isotope Analysis in Ecology
- Cryospheric studies and observations
- Spacecraft and Cryogenic Technologies
- Scientific Research and Discoveries
- Nuclear Physics and Applications
- Arctic and Antarctic ice dynamics
- Marine and environmental studies
- Space Satellite Systems and Control
- Spacecraft Design and Technology
- Aeolian processes and effects
- Atmospheric and Environmental Gas Dynamics
- Geophysics and Gravity Measurements
- Remote Sensing and LiDAR Applications
- Gamma-ray bursts and supernovae
- Pacific and Southeast Asian Studies
- Geological Modeling and Analysis
- Maritime and Coastal Archaeology
Goddard Space Flight Center
2014-2024
National Aeronautics and Space Administration
1986-2023
Johns Hopkins University Applied Physics Laboratory
2021
Ames Research Center
2002
Massachusetts Institute of Technology
1998-2001
International Space Station
2001
Czech Academy of Sciences, Institute of Hydrodynamics
2000
Wallops Flight Facility
2000
Woodwell Climate Research Center
2000
United States Geological Survey
2000
The Mars Orbiter Laser Altimeter (MOLA), an instrument on the Global Surveyor spacecraft, has measured topography, surface roughness, and 1.064‐μm reflectivity of heights volatile dust clouds. This paper discusses function MOLA acquisition, processing, correction observations to produce global data sets. altimeter measurements have been converted both gridded spherical harmonic models for topography shape that vertical radial accuracies ∼1 m with respect planet's center mass. current...
Elevations measured by the Mars Orbiter Laser Altimeter have yielded a high-accuracy global map of topography Mars. Dominant features include low northern hemisphere, Tharsis province, and Hellas impact basin. The hemisphere depression is primarily long-wavelength effect that has been shaped an internal mechanism. consists two broad rises. Material excavated from contributes to high elevation southern scarp along hemispheric boundary. present three major drainage centers, with lowlands being...
The primary objective of the Mars Observer laser altimeter (MOLA) investigation is to determine globally topography at a level suitable for addressing problems in geology and geophysics. Secondary objectives are characterize 1064‐nm wavelength surface reflectivity contribute analyses global mineralogy seasonal albedo changes, assist atmospheric circulation, provide geodetic control topographic context assessment possible future landing sites. principal components MOLA diode‐pumped,...
Hydrogen has been inferred to occur in enhanced concentrations within permanently shadowed regions and, hence, the coldest areas of lunar poles. The Lunar Crater Observation and Sensing Satellite (LCROSS) mission was designed detect hydrogen-bearing volatiles directly. Neutron flux measurements Moon's south polar region from Exploration Detector (LEND) on Reconnaissance Orbiter (LRO) spacecraft were used select optimal impact site for LCROSS. LEND data show several where epithermal neutron...
Abstract The Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) spacecraft landed successfully on Mars imaged the surface to characterize surficial geology. Here we report geology subsurface structure of landing site aid in situ geophysical investigations. InSight a degraded impact crater Elysium Planitia smooth sandy, granule- pebble-rich with few rocks. Superposed craters are common eolian bedforms sparse. During landing, pulsed retrorockets modified...
The Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging (DAVINCI) mission described herein has been selected for flight to as part the NASA Discovery Program. DAVINCI will be first incorporate science-driven flybys an instrumented descent sphere into a unified architecture. anticipated scientific outcome new understanding atmosphere, surface, evolutionary path possibly once-habitable planet analog hot terrestrial exoplanets. primary design features preferred launch in...
Abstract Europa is a premier target for advancing both planetary science and astrobiology, as well opening new window into the burgeoning field of comparative oceanography. The potentially habitable subsurface ocean may harbor life, globally young comparatively thin ice shell contain biosignatures that are readily accessible to surface lander. Europa’s icy also offers opportunity study tectonics geologic cycles across range mechanisms compositions. Here we detail goals mission architecture...
The Hunga Tonga-Hunga Ha'apai (HTHH) volcanic eruption in January 2022 generated catastrophic tsunami and contends for the largest natural explosion more than a century. main island, Tongatapu, suffered waves up to 17 m, Tofua Island 45 comfortably placing HTHH "megatsunami" league. We present simulation of Tongan Archipelago calibrated by field observations, drone, satellite data. Our emphasizes how complex shallow bathymetry area acted as low-velocity wave trap, capturing 1 hour. Despite...
Elevations from the Mars Orbiter Laser Altimeter (MOLA) have been used to construct a precise topographic map of martian north polar region. The northern ice cap has maximum elevation 3 kilometers above its surroundings but lies within 5-kilometer-deep hemispheric depression that is contiguous with area into which most outflow channels emptied. Polar topography displays evidence modification by ablation, flow, and wind consistent primarily H 2 O composition. Correlation images suggests was...
The first 18 tracks of laser altimeter data across the northern hemisphere Mars from Global Surveyor spacecraft show that planet at latitudes north 50° is exceptionally flat; slopes and surface roughness increase toward equator. polar layered terrain appears to be a thick ice-rich formation with non-equilibrium planform indicative ablation near periphery. Slope relations suggest Tharsis province was uplifted in past. A profile Ares Vallis channel suggests discharge through much greater than...
The Mars Crater Morphology Consortium recommends the use of a standardized nomenclature system when discussing Martian impact crater ejecta morphologies. utilizes nongenetic descriptors to identify various morphologies seen on Mars. This is designed facilitate communication and collaboration between researchers. morphology databases will be archived through U.S. Geological Survey in Flagstaff, where comprehensive catalog morphologic information maintained.
Measurements from the Near Earth Asteroid Rendezvous (NEAR)-Shoemaker Laser Rangefinder (NLR) indicate that asteroid 433 Eros is a consolidated body with complex shape dominated by collisions. The offset between asteroid's center of mass and figure indicates small deviation homogeneous internal structure most simply explained variations in mechanical structure. Regional-scale relief slope distributions show evidence for control topography competent substrate. Impact crater morphology...
Abstract The Mars Science Laboratory Mast camera and Descent Imager investigations were designed, built, operated by Malin Space Systems of San Diego, CA. They share common electronics focal plane designs but have different optics. There are two Mastcams dissimilar length. Mastcam‐34 has an f /8, 34 mm length lens, the M‐100 /10, 100 lens. M‐34 field view is about 20° × 15° with instantaneous (IFOV) 218 μrad; (FOV) 6.8° 5.1° IFOV 74 μrad. can focus from 0.5 m to infinity, ~1.6 infinity. All...
Carbonaceous asteroids, such as (101955) Bennu, preserve material from the early Solar System, including volatile compounds and organic molecules. We report spacecraft imaging spectral data collected during after retrieval of a sample Bennu’s surface. The sampling event mobilized rocks dust into debris plume, excavating 9-meter-long elliptical crater. This exposed is darker, spectrally redder, more abundant in fine particulates than original bulk density displaced subsurface was 500 to 700...
The use of a combination several measurement techniques to investigate the dielectric properties 80 rock samples in microwave region is discussed. real part relative constant epsilon ' was measured 0.1-GHz steps from 0.5 18 GHz, and imaginary " at five frequencies extending between 1.6 16 GHz. In addition measurements, bulk density for all chemical composition determined 56 samples. This study shows that frequency-independent over range 0.5-18 GHz samples, rho /sub b/ accounts about 50%...
Results are presented for the LEND instrument onboard LRO detection of local spots suppression and excess epithermal neutron emission at lunar poles. Twelve Neutron Suppression Regions (NSRs) Excess (NERs) detected. It is shown using data from LOLA Diviner instruments that six NSRs have empirical property “ less irradiation lower temperature – fewer neutrons. ” These may be identified with water‐ice rich permafrost on Moon. detected include in both permanently shadowed illuminated areas,...
Abstract In this work we discuss various selected mission concepts addressing Venus evolution through time. More specifically, address investigations and payload instrument supporting scientific goals open questions presented in the companion articles of volume. Also included are their related (observations & modeling) discussion which measurements future data products needed to better constrain Venus’ atmosphere, climate, surface, interior habitability A new fleet missions has been...
Hematite‐bearing deposits in the Terra Meridiani region of Mars constitute top stratum a partially eroded layered complex that covers dissected Noachian‐aged cratered terrain. The hematite unit consists dark plains and dunes covering bright substrate. This substrate is fully exposed beyond borders hematite‐bearing deposit polygonal ground separated by ridges or valleys, together with have been into variety landforms. covered regional‐scale aeolian mantle thickens toward north. exhibits low...
The Mars Orbiter Laser Altimeter (MOLA) measured the pulse width and energy of altimetric laser returns during course two years operations. As secondary science objectives, MOLA obtains footprint‐scale roughness bidirectional reflectivity Mars. underwent extensive preflight calibration measurements were monitored continuously in flight, but anomalous values have been inferred. A widths using inflight data yields a slope‐corrected over ∼75‐m‐diameter footprints that may be used for...