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James Johnson

Publications and source records attributed to James Johnson.

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2023

Assessing the Relocation of Artemis Foundational Lunar Surface Concepts

The National Aeronautics and Space Administration (NASA) has defined a functionally based Moon to Mars (M2M) architecture consisting of four key human exploration segments: human lunar return (HLR), foundational exploration (FE), sustained lunar evolution (SLE), and humans to Mars (H2M). These segments are portions of the architecture which represent a stepwise increase in complexity and achievement of M2M objectives [1]. As systems are deployed during the FE segment, it may be desired or even necessary to relocate these elements on the lunar surface as the architecture transitions into the SLE segment. While some Artemis elements under development, such as rovers, are being designed for mobility during both crewed and uncrewed/dormant periods, other architectural concepts do not currently carry a mobility capability. In preparation for the Agency’s 2023 Architecture Concept Review (ACR), a team was assembled to establish a methodology for assessing the relocation feasibility of normally stationary elements. Such a capability could be applied locally or regionally, and might allow for re-purposing previously occupied terrain, expansion of exploration range, aggregation of habitation elements, or retiring systems at the end of their useful service life. The assembled NASA team investigated the relocation trade space through defining a representative concept of operations (ConOps) and assessing possible system impacts. The team focused predominately on the relocation of medium and large surface habitat architectural concepts through surface-based traverses utilizing separable mobility platforms (SMP). A representative mobility platform model was placed through simulation to analyze the possible energy requirements and dynamic illumination impacts. Preliminary assessment indicated that element relocation might be achievable, however significant system and architectural-level risks still need to be quantified. Future analysis will assist in determining what degree of element relocation provides the greatest benefit to achieving a sustained lunar presence. [1] NASA. (2022). Moon to Mars Objectives. Retrieved from: https://www.nasa.gov/sites/default/files/atoms/files/m2m-objectives-exec-summary.pdf

Artemis↗
NASA NTRSDate not supplied

ASCoT 3: Nonlinear Principal Components Analysis and Uncertainty Quantification in Early Concept Spacecraft Flight Software Cost Estimation

For mission planners and evaluators alike, value in cost models comes from a mean or median prediction, an understanding of the uncertainty on that prediction, and an understanding of model performance. Here we apply advanced statistical and machine learning methods to spacecraft flight software cost, effort, and SLOC estimation, and present the results in the latest version of the Analogy Software Cost Tool (ASCoT). We present in- and out-of-sample performance metrics for our models, each of which incorporate some amount of epistemic uncertainty. ASCoT, hosted on the One NASA Cost Engineering (ONCE) database via the Online NASA Space Estimation Tool (ONSET), was first showcased in 2016 as a number of analogy-based models and methods (kNN and Clustering) to support early project formulation. This ASCoT update improves upon the previous analogic methods by incorporating uncertainty in the data transformations. In particular, we use a Nonlinear Principal Components Analysis (NLPCA) to deal with ordinal data.

Robotic Spacecraft↗
NASA NTRSDate not supplied

An Oveview of TROPESS Data Products and Services at the NASA GES DISC

The TRopospheric Ozone and Precursors from Earth System Sounding (TROPESS) project generates Earth System Data Records (ESDRs) of ozone, and other atmospheric constituents (CH4,CO, H2O, HDO, NH3, PAN and temperature) by processing data from multiple satellites through a common retrieval algorithm and ground data system. Satellite Level-1B input data used in generating the TROPESS L2 data products include CrIS NOAA-20 (JPSS-1), CrIS SNPP, AIRS Aqua, OMI Aura, and TROPOMI S5P. The common retrieval framework is known as the MUlti-SpEctra, MUlti-SpEcies, Multi-SEnsors (MUSES) science data processing system (MUSES-SDPS). Several of the TROPESS data products are now available from the NASA Goddard Earth Sciences Data and Information Service Center (GES DISC) for users to download. In this presentation we provide an overview of the various TROPESS data products. These data products can be divided into the following Forward Stream types: Standard Products, Summary Products, and Full-Archival Products. Standard Products are for users that are doing full analysis with avenging kernel and covariance corresponding to retrieved vertical profiles. Summary products have a smaller file size and are more convenient for first-look and rapid analysis, include total and partial columns, as well as column averaging kernels. The Full-Archival Products will contain all information used in creating the data. TROPESS also creates Special Products, provided on an as-needed and as-available basis to support NASA field missions and individual-investigator requests over specific regions. Eventually, TROPESS will also produce and deliver a set of Reanalysis Stream products. Data at the GES DISC are being transitioned into the "Cloud". This will allow users with "Cloud” access to perform data analysis directly on the data without downloading the data to their system. Services, such as subsetting and data visualization, will also be provided for TROPESS data products at the GES DISC.

James Johnson↗
NASA NTRSDate not supplied

Preserving NASA Historic and Current Mission Data and Adding Value to These for Future Researchers

The NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) has been actively involved in many aspects of ensuring the long-term preservation of NASA earth science data and knowledge. This involves both the recovery and preservation of early NASA meteorological and other earth observation data, as well as preserving the more recent Earth Observation System (EOS) mission data sets which continue or have reached their end of lifetime. The GES DISC adds value to these preserved data by adding metadata and making the data available online to future researchers. The early NASA meteorological and earth observation data sets from the 1960s and 70s were originally archived on magnetic tapes, and visualizations of these data were preserved on 70-mm film. As these media have aged, their contents have been at risk of permanent loss. NASA has given the task of preserving these early data sets to the GES DISC and making these data sets easily available to the public. The data from these early missions are potentially useful to climate researchers as these are some of the only global measurements made at their time. These old data on magnetic tapes and film strips do not contain easily readable metadata, and so to add value the GES DISC has added digital metadata to them so that the data are searchable and findable. The GES DISC is also involved in preserving the data and knowledge from the EOS era missions. The GES DISC follows the guidelines developed for the preservation of data as specified in the NASA EOS Data and Information System (EOSDIS) Earth Science Data Preservation Content Specification (423-SPEC-001) document. To date, the GES DISC has consulted with the data science teams from the following missions: UARS, Earth Probe TOMS, Aura HIRDLS, and SORCE, in order to properly preserve their data and accompanying documentation. The GES DISC is also currently working with the EOS science teams from TRMM, AIRS, MLS, OMI and additional missions to ensure that the relevant documents and data sets are properly archived for future researchers. A standardized procedure for mission data preservation following 423-SPEC-001 makes preservation among the many NASA EOSDIS data centers uniform, so that these could be transitioned easily to a common EOSDIS preservation repository. This presentation will give an overview of the preservation and recovery of the old NASA historical data sets archived at the GES DISC, as well as the data and documentation preservation efforts of the EOS era missions.

James Johnson↗
NASA NTRSDate not supplied

OMI Phase-F Data Preservation

The NASA GES DISC is the primary archive for the Aura OMI products. After 20 years of operations, the OMI instrument is nearing its end and entering Phase-F (closeout). It is time to begin the process of preserving the data, documentation, software and associated information that were produced by the OMI project over its lifetime.

James Johnson↗