Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Skip to content

Try the next-generation Data Catalog at catalog-beta.data.gov and help shape it with your feedback.

  • Feedback

    • Voyager 2 Jupiter Plasma Science (PLS) Derived Ion Outbound Magnetosheath M-Mode, Version 1.0, 96 s Data

    Metadata Updated: March 13, 2026

    • Data Set Overview\n =================\n\n+-----------------------------------------------------+\n| Data Set Characteristics | Value |\n-------------------------------------------------------\n| Instrument P.I. | JOHN D. RICHARDSON |\n| Data Supplier | JOHN D. RICHARDSON |\n| Data Sampling Rate | 96 SECONDS |\n| Data Set Start Time | 1979-07-23T23:42:34.541Z |\n| Data Set Stop Time | 1979-08-10T04:04:57.070Z |\n+-----------------------------------------------------+\n\nThis Data Set contains Plasma Parameters from Voyager 2 outbound from Jupiter from the Magnetotail through the Solar Wind. Fit and Moment Parameters are given; the Fit Parameters assume a single, isotropic convected Proton Maxwellian Distribution. Although Magnetotail Data is provided, these Data are unreliable; the Density can be used as an upper Limit to the actual Density. Solar Wind Data are also provided and are reliable. These M-Mode Data are the best Data to use in most Regions of the Magnetosheath. Magnetotail Data in this Data Set are included mainly to put the Sheath Data in context and to show the magnetopause.\n\n Parameters\n ==========\n\n Data Set Parameter ION DENSITY\n ==============================\n\n+----------------------------------------------+\n| Parameter Characteristics | Value |\n------------------------------------------------\n| Data Set Parameter Name | ION DENSITY |\n| Data Set Parameter Unit | CM^-3 |\n| Sampling Parameter Name | TIME |\n| Sampling Parameter Unit | SECOND |\n| Minimum Sampling Parameter | UNK |\n| Maximum Sampling Parameter | UNK |\n| Sampling Parameter Interval | UNK |\n| Minimum Available Sampling Int | UNK |\n| Noise Level | UNK |\n+----------------------------------------------+\n\nA derived Parameter equaling the Number of Ions per Unit Volume over a specified Range of Ion Energy, Energy per Charge, or Energy per Nucleon. Discrimination with regard to Mass and or Charge State is necessary to obtain this Quantity, however, Mass and Charge State are often assumed due to Instrument Limitations.\n\nMany different Forms of Ion Density are derived. Some are distinguished by their Composition (N+, Proton, Ion, etc.) or their Method of Derivation (Maxwellian Fit, Method of Moments). In some cases, more than one Type of Density will be provided in a single Data Set. In general, if more than one Ion Species is analyzed, either by Moment or Fit, a total Density will be provided which is the Sum of the Ion Densities. If a Plasma Component does not have a Maxwellian Distribution the actual Distribution can be represented as the Sum of several Maxwellians, in which case the Density of each Maxwellian is given.\n\n Data Set Parameter ION THERMAL SPEED\n ====================================\n\n+----------------------------------------------------+\n| Parameter Characteristics | Value |\n------------------------------------------------------\n| Data Set Parameter Name | ION THERMAL SPEED |\n| Data Set Parameter Unit | KM/S |\n| Sampling Parameter Name | TIME |\n| Sampling Parameter Unit | SECOND |\n| Minimum Sampling Parameter | UNK |\n| Maximum Sampling Parameter | UNK |\n| Sampling Parameter Interval | UNK |\n| Minimum Available Sampling Int | UNK |\n| Noise Level | UNK |\n+----------------------------------------------------+\n\nA Measure of the Velocity associated with the Temperature of the Ions. It is formally defined as the Ion Thermal Speed squared equals two times K (Boltzmann Constant) times T (Ion Temperature) divided by M (Ion Mass). Each Component of a Plasma has a Thermal Speed associated with it.\n\n Data Set Parameter ION VELOCITY\n ===============================\n\n+-----------------------------------------------+\n| Parameter Characteristics | Value |\n-------------------------------------------------\n| Data Set Parameter Name | ION VELOCITY |\n| Data Set Parameter Unit | KM/S |\n| Sampling Parameter Name | TIME |\n| Sampling Parameter Unit | SECOND |\n| Minimum Sampling Parameter | UNK |\n| Maximum Sampling Parameter | UNK |\n| Sampling Parameter Interval | UNK |\n| Minimum Available Sampling Int | UNK |\n| Noise Level | UNK |\n+-----------------------------------------------+\n\nA derived Parameter giving the average Speed and Direction of Motion of a Plasma or Plasma Component. The Velocity can be obtained by taking the first Moment of the Distribution Function or by simulating the Observations with some known Distribution Function, usually a Maxwellian, to the Distribution. Velocities are given in Heliographic (RTN) Coordinates:\n\n R is radially away from Sun\n T is in Equatorial Plane of the Sun and positive in the Direction of Solar Rotation\n N completes right-handed System\n\n+-------------------------------------------------+\n| Source Instrument Characteristics | Value |\n---------------------------------------------------\n| Instrument Host ID | VG2 |\n| Data Set Parameter Name | ION DENSITY |\n+-------------------------------------------------+

    Access & Use Information

    Public: This dataset is intended for public access and use. License: See this page for license information.

    Downloads & Resources

    No file downloads have been provided. The publisher may provide downloads in the future or they may be available from their other links.

    Dates

    Metadata Created Date March 13, 2026
    Metadata Updated Date March 13, 2026

    Metadata Source

    Harvested from NASA Data.json

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date March 13, 2026
    Metadata Updated Date March 13, 2026
    Publisher PDS PPI
    Maintainer
    Identifier /SDE/SPASE_JSON/|a50c08950e374f3795275a3982692775
    Data Last Modified 2026-03-09
    Category Heliophysics
    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 0a79dd19-cca8-4298-86d0-1def264a0f80
    Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
    Harvest Source Title NASA Data.json
    License https://www.usa.gov/government-works
    Program Code 026:000
    Source Datajson Identifier True
    Source Hash b35b9f3f3c1db7143e4ea68531d7423de26d0ff62cb0145b7e9ba1fdb52b8c9b
    Source Schema Version 1.1

    Didn't find what you're looking for? Suggest a dataset here.