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Wong, M.

Publications and source records attributed to Wong, M..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

No Pixel Left Behind: Interactively Visualizing ''Everything'' from NASA's Earth Observations

The problem: satellite swath overlaps. Polar orbiting satellites like Terra, Aqua, and the joint NASA/NOAA Suomi-NPP satellite circle the globe from pole to pole, collecting data daily, swath by swath. Having this density of data is great for building a comprehensive mosaic of the planet, but sometimes there is something interesting occurring in one swath but is covered by a subsequent swath when the satellite passes over 90 minutes later. With our new prototype based on Worldview and the Global Imagery Browse Services (GIBS), we combine the best of both worlds to interactively visualize the entire globe as a mosaic and allow the user to _peel away the overlaps_ to see every pixel that was observed by the satellite. This ability to look at every pixel - and to know when they were captured - is especially important near the poles where swath overlaps are most common.

Boller, R.↗
NASA NTRS2018

New Capabilities, Products and Usage of NASA Earth Imagery for Near Real Time Applications

NASA's Worldview and Global Imagery Browse Services (GIBS) have provided near real time (NRT) imagery to the public since 2011 and continue to add new capabilities and products. As a web map app for GIBS, Worldview (https://worldview.earthdata.nasa.gov) has recently added new features to support NRT applications such as a "before" and "after" comparison capability and support for geostationary imagery. As an open set of standards-based web map services, GIBS (https://earthdata.nasa.gov/gibs) has added several new NRT imagery products and will soon add new capabilities for better integration with Geographic Information System (GIS) clients. One of NASA's original NRT imagery systems and a long-running workhorse, Rapid Response, has been retired and replaced with a modern, mobile-friendly, and low-bandwidth app dubbed Worldview Snapshots (https://wvs.earthdata.nasa.gov). Finally, this presentation will demonstrate recent usage of these tools and services by those in the NRT community.

Boller, R.↗
NASA NTRS2017

Exposing NASA's Earth Observations to the Applications Community and Public

NASA's Earth Observing System (EOS) generates a wealth of data products which are generally intended for scientific research. In recent years, however, this data has also become more accessible to the applications community and public through the Worldview app and Global Imagery Browse Services (GIBS). These mapping interfaces provide historical and near real time access to NASA's Earth observations for a wide range of uses. This presentation will focus on how the applications community, public, and media use these interfaces for decision-making, leisure, and anything in between.

web mappin↗
NASA NTRS2016

Web Map Apps using NASA's Earth Observing Fleet

Through the miracle of open web mapping services for satellite imagery, a garden of new applications has sprouted to monitor the planet across a variety of domains. The Global Imagery Browse Services (GIBS) provide free and open access to full resolution imagery captured by NASAs Earth observing fleet. Spanning 15+ years and running through as recently as a few hours ago, GIBS aims to provide a general-purpose window into NASA's vast archive of the planet. While the vast nature of this archive can be daunting, many domain-specific applications have been built to meet the needs of their respective communities. This presentation will demonstrate a diverse set of these new applications which can take planetarium visitors into (virtual) orbit, guide fire resource managers to hotspots, help anglers find their next catch, illustrate global air quality patterns to local regulators, and even spur a friendly competition to find clouds which are shaped the most like cats. We hope this garden will continue to grow and will illustrate upcoming upgrades to GIBS which may open new pathways for development. data visualization, web services, open access

data visualization↗
NASA NTRS2014

Detection of Nitric Oxide by the Sample Analysis at Mars (SAM) Instrument Implications for the Presence of Nitrates

One of the main goals of the Mars Science Laboratory is to determine whether the planet ever had environmental conditions able to support microbial life. Nitrogen is a fundamental element for life, and is present in structural (e.g., proteins), catalytic (e.g., enzymes and ribozymes), energy transfer (e.g., ATP) and information storage (RNA and DNA) biomolecules. Planetary models suggest that molecular nitrogen was abundant in the early Martian atmosphere, but was rapidly lost to space by photochemistry, sputtering impact erosion, and oxidized and deposited to the surface as nitrate. Nitrates are a fundamental source for nitrogen to terrestrial microorganisms. Therefore, the detection of nitrates in soils and rocks is important to assess the habitability of a Martian environment. SAM is capable of detecting nitrates by their thermal decomposition into nitric oxide, NO. Here we analyze the release of NO from soils and rocks examined by the SAM instrument at Gale crater, and discuss its origin.

Navarro-Gonzalez, R.↗
NASA NTRS2014

Reconciling the Differences between the Measurements of CO2 Isotopes by the Phoenix and MSL Landers

Precise stable isotope measurements of the CO2 in the martian atmosphere have the potential to provide important constraints for our understanding of the history of volatiles, the carbon cycle, current atmospheric processes, and the degree of water/rock interaction on Mars. There have been several different measurements by landers and Earth based systems performed in recent years that have not been in agreement. In particular, measurements of the isotopic composition of martian atmospheric CO2 by the Thermal and Evolved Gas Analyzer (TEGA) instrument on the Mars Phoenix Lander and the Sample Analysis at Mars (SAM) instrument on the Mars Science Laboratory (MSL) are in stark disagreement. This work attempts to use measurements of mass 45 and mass 46 of martian atmospheric CO2 by the SAM and TEGA instruments to search for agreement as a first step towards reaching a consensus measurement that might be supported by data from both instruments.

Niles, P. B.↗
NASA NTRS2013

Possible Detection of Nitrates on Mars by the Sample Analysis at Mars (SAM) Instrument

Planetary models suggest that nitrogen was abundant in the early Martian atmosphere as dinitrogen (N2). However, it has been lost by sputtering and photochemical loss to space [1, 2], impact erosion [3], and chemical oxidation to nitrates [4]. Nitrates, produced early in Mars history, are later decomposed back into N2 by the current impact flux [5], making possible a nitrogen cycle on Mars. It is estimated that a layer of about 3 m of pure NaNO3 should be distributed globally on Mars [5]. Nitrates are a fundamental source for nitrogen to terrestrial microorganisms. Therefore, the detection of soil nitrates is important to assess habitability in the Martian environment. The only previous mission that was designed to search for soil nitrates was the Phoenix mission but was unable to detect evolved N-containing species by TEGA and the MECA WCL [6]. Nitrates have been tentatively identified in the Nakhla meteorite [7]. The purpose of this work is to determine if nitrates were detected in first solid sample (Rocknest) in Gale Crater examined by the SAM instrument.

Navarro-Gonzalez, R.↗
NASA NTRS2013

Preliminary Interpretations of Atmospheric Stable Isotopes and Argon from Mars Science Laboratory (SAM)

Given the broad agreement between C, H, and O isotopic ratios in the modern atmosphere and the ALH 84001 meteorite, it is possible that these reservoirs were established after early atmospheric loss prior to 4 Ga. The preservation of these signals over this long period of history can be explained in several slightly different ways: 1) C, O, and H have remained static in the atmosphere and have not exchanged with the surface over the past 4 Ga; 2) C, O, and H in the atmosphere have potentially varied widely over history but have been continually buffered by larger reservoirs in the crust which have remained unchanged over the past 4 Ga. This second possibility allows for potentially large variations in atmospheric pressure to occur as CO2 is recycled back into the atmosphere from crustal reservoirs or degassed from the mantle.

Jones, J. H.↗
NASA NTRS2011

The 2010-2011 Revival of Jupiter's South Equatorial Belt: Perturbations of Temperatures, Clouds and Composition from Infrared Observations

On 2010 November 9, a perturbation appeared in Jupiter's South Equatorial Belt (SEB), which began a classical "revival" of the SEB, returning the entire axisymmetric region to its normal dark color from its anomalous, light, "faded" state. The early revival is marked by strong upwelling gas at the outbreak location, to the west of which appear alternating clear and cloudy regions. Clear regions are correlated with dark clouds near the outbreak and in a southern retrograding branch but less so in a northern prograding branch. A 5-micrometer image from 2010 March 1 shows much of the SEB closer to a pre-faded state.

atmosphere↗
NASA NTRS2011

Long-Term Evolution of the Aerosol Debris Cloud Produced by the 2009 Impact on Jupiter

We present a study of the long-term evolution of the cloud of aerosols produced in the atmosphere of Jupiter by the impact of an object on 19 July 2009. The work is based on images obtained during 5 months from the impact to 31 December 2009 taken in visible continuum wavelengths and from 20 July 2009 to 28 May 2010 taken in near-infrared deep hydrogen-methane absorption bands at 2.1-2.3 micron. The impact cloud expanded zonally from approximately 5000 km (July 19) to 225,000 km (29 October, about 180 deg in longitude), remaining meridionally localized within a latitude band from 53.5 deg S to 61.5 deg S planetographic latitude. During the first two months after its formation the site showed heterogeneous structure with 500-1000 km sized embedded spots. Later the reflectivity of the debris field became more homogeneous due to clump mergers. The cloud was mainly dispersed in longitude by the dominant zonal winds and their meridional shear, during the initial stages, localized motions may have been induced by thermal perturbation caused by the impact's energy deposition. The tracking of individual spots within the impact cloud shows that the westward jet at 56.5 deg S latitude increases its eastward velocity with altitude above the tropopause by 5- 10 m/s. The corresponding vertical wind shear is low, about 1 m/s per scale height in agreement with previous thermal wind estimations. We found evidence for discrete localized meridional motions with speeds of 1-2 m/s. Two numerical models are used to simulate the observed cloud dispersion. One is a pure advection of the aerosols by the winds and their shears. The other uses the EPIC code, a nonlinear calculation of the evolution of the potential vorticity field generated by a heat pulse that simulates the impact. Both models reproduce the observed global structure of the cloud and the dominant zonal dispersion of the aerosols, but not the details of the cloud morphology. The reflectivity of the impact cloud decreased exponentially with a characteristic timescale of 15 days; we can explain this behavior with a radiative transfer model of the cloud optical depth coupled to an advection model of the cloud dispersion by the wind shears. The expected sedimentation time in the stratosphere (altitude levels 5-100 mbar) for the small aerosol particles forming the cloud is 45-200 days, thus aerosols were removed vertically over the long term following their zonal dispersion. No evidence of the cloud was detected 10 months after the impact.

Sanchez-Lavega, A.↗
NASA NTRS2009

Temporal Variations in Jupiter's Atmosphere

In recent years, Jupiter has undergone many atmospheric changes from storms turning red to global. cloud upheavals, and most recently, a cornet or asteroid impact. Yet, on top of these seemingly random changes events there are also periodic phenomena, analogous to observed Earth and Saturn atmospheric oscillations. We will present 15 years of Hubble data, from 1994 to 2009, to show how the equatorial tropospheric cloud deck and winds have varied over that time, focusing on the F953N, F41 ON and F255W filters. These filters give leverage on wind speeds plus cloud opacity, cloud height and tropospheric haze thickness, and stratospheric haze, respectively. The wind data consistently show a periodic oscillation near 7-8 S latitude. We will discuss the potential for variations with longitude and cloud height, within the calibration limits of those filters. Finally, we will discuss the role that large atmospheric events, such as the impacts in 1994 and 2009, and the global upheaval of 2007, have on temporal studies, This work was supported by a grant from the NASA Planetary Atmospheres Program. HST observational support was provided by NASA through grants from Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under contract NAS5-26555.

Simon-Miller, Amy A.↗
NASA NTRS2003

Measurement of Surface Composition for the Icy Galilean Moons Via Neutral and Ion Mass Spectrometry from Orbit with JIMO

In this paper, we will provide insights into mass spectrometer requirements. In addition, we will describe the modeling of the neutrals ejected from likely surface materials and their ionization rates in the Jovian environment. We will use such models to connect the mass spectra measurements of the freshly formed ions to surface composition. We will also discuss what possible compositional signatures are for endogenic materials other than water ice. Finally, since a goal is to identify material composition with surface features, we will describe the transport of neutrals ejected from the surface prior to detection by either an ion or neutral mass spectrometer.

Wong, M.↗
NASA NTRS2001

Small Martian North Polar Volcanoes: Topographic Implications for Eruptive Styles

We characterize and model small volcanoes in the martian mid-latitude and near-polar regions. Regional differences and possible latitude-dependent geometry parameters hint that subsurface volatiles may be significant for polar eruptions. Additional information is contained in the original extended abstract.

Sakimoto, S. E. H.↗