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    • This is a Non-Federal dataset covered by different Terms of Use than Data.gov.

    GRACE OCEAN BOTTOM GEOPOTENTIAL COEFFICIENTS CSR RELEASE 6.0 GAD

    Metadata Updated: February 22, 2025

    FOR EXPERT USE ONLY. This dataset contains estimates of ocean bottom pressure derived from the Gravity Recovery and Climate Experiment (GRACE) mission measurements, produced by the Center for Space Research (CSR) at University of Texas at Austin. The data are in spherical harmonics averaged over approximately a month. The primary objective of the GRACE mission is to obtain accurate estimates of the mean and time-variable components of the gravity field variations. This objective is achieved by making continuous measurements of the change in distance between twin spacecraft, co-orbiting in about 500 km altitude, near circular, polar orbit, spaced approximately 200 km apart, using a microwave ranging system. In addition to these range change, the non-gravitional forces are measured on each satellite using a high accuracy electrostatic, room-temperature accelerometer. The satellite orientation and position (and timing) are precisely measured using twin star cameras and a GPS receiver, respectively. Spatial and temporal variations in the gravity field affect the orbits (or trajectories) of the twin spacecraft differently. These differences are manifested as changes in the distance between the spacecraft, as they orbit the Earth. This change in distance is reflected in the time-of-flight of microwave signals transmitted and received nearly simultaneously between the two spacecraft. The change in this time of fight is continuously measured by tracking the phase of the microwave carrier signals. The so called dual-one-way range change measurements can be reconstructed from these phase measurements. This range change (or its numerically derived derivatives), along with other mission and ancillary data, is subsequently analyzed to extract the parameters of an Earth gravity field model.

    Access & Use Information

    Public: This dataset is intended for public access and use. Non-Federal: This dataset is covered by different Terms of Use than Data.gov. License: No license information was provided.

    Downloads & Resources

    Dates

    Metadata Created Date February 22, 2025
    Metadata Updated Date February 22, 2025

    Metadata Source

    Harvested from nasa test json

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date February 22, 2025
    Metadata Updated Date February 22, 2025
    Publisher NASA/JPL/PODAAC
    Maintainer
    Identifier C2491772128-POCLOUD
    Data First Published 2018-04-26
    Language en-US
    Data Last Modified 2025-02-19
    Category GRACE, geospatial
    Public Access Level public
    Bureau Code 026:00
    Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
    Schema Version https://project-open-data.cio.gov/v1.1/schema
    Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
    Harvest Object Id 5b07f065-fe04-4cd1-be00-8d741e454dd3
    Harvest Source Id a73e0c30-4684-40ef-908e-d22e9e9e5f86
    Harvest Source Title nasa test json
    Homepage URL https://doi.org/10.5067/GRGAD-20C06
    Metadata Type geospatial
    Old Spatial -180.0 -88.0 180.0 88.0
    Program Code 026:001
    Source Datajson Identifier True
    Source Hash cda36ecbbe0ebeeb9be3d27a44d0e5c7897d5f01831f8ae37692fd2ecb4b6dd3
    Source Schema Version 1.1
    Spatial
    Temporal 2002-04-05T00:00:00Z/2017-06-30T00:00:00Z

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