2.7.2 https://spdx.org/licenses/ CC0-1.0 https://spdx.org/licenses/CC0-1.0.html Creative Commons Zero v1.0 Universal CC0 1.0 Universal is the Creative Commons license applicable to all publicly available SPASE metadata descriptions spase://NASA/NumericalData/IMP7/Ephemeris/PT12M NASA NumericalData IMP 7 12-min Position Data 2026-07-21T12:05:21Z 2025-05-14T21:14:38Z Only known prior ReleaseDate of the metadata 2025-12-04T13:29:33Z Added MetadataRightsList and RightsList(s). Added ResourceType and NamingAuthority. Updated to 2.7.1. Changed http to https in top-level schemaLocation attribute. Fixed version number separator in top-level schemaLocation attribute. ZCB 2026-07-21T12:05:21Z Added HelioData InformationURL. JWL 2026-09-25T11:21:29 Added Publication info TLK IMP-7 satellite position and magnetic field model information. NASA Space Physics Data Facility (SPDF) Satellite Situation Center (SSC). Ness, Norman F. 2025-05-14T21:14:38Z Space Physics Data Facility spase://SMWG/Person/Robert.E.McGuire GeneralContact spase://SMWG/Person/Norma.F.Ness ProjectScientist HelioData https://helio.data.nasa.gov/dataset/IMP7_Ephemeris_PT12M The HelioData dataset page provides an overview of the dataset with access links, associated variables, and more. spase://VSPO/NumericalData/IMP7/Ephemeris/PT12M spase://SMWG/Repository/NASA/GSFC/SPDF Online Open https://spdx.org/licenses/ CC0-1.0 https://spdx.org/licenses/CC0-1.0.html Creative Commons Zero v1.0 Universal CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products SSCWeb https://sscweb.gsfc.nasa.gov/cgi-bin/Locator.cgi imp7 CDF spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SSCWeb Programmatic Data Access https://sscweb.gsfc.nasa.gov/WS/sscr/2/observatories/imp7/clientLibraryExample/ imp7 Access to this data from common programming environments. Note: this AccessInformation element was added by HDPWS. Binary spase://SMWG/Repository/NASA/GSFC/SPDF Online Open 4D Orbit Viewer https://sscweb.gsfc.nasa.gov/4dorbit/?sc=imp7 imp7 4D viewer for this data. Note: this AccessInformation element was added by HDPWS. HTML spase://SMWG/Instrument/IMP7/Ephemeris Ephemeris 1972-09-26T00:00:00.000Z 1978-10-01T00:00:00.000Z PT12M Heliosphere.NearEarth Earth.Magnetosphere Earth.NearSurface Epoch Time Epoch Number of milliseconds since the CDF epoch ms 1e-3>s 01-Jan-1956 00:00:00.000 01-Jan-2083 00:00:00.000 -1.0E31 Temporal GEI position XYZ_GEI Spacecraft position in GEI km 1e3>m Cartesian GEI 3 x Component.I 1 -1.0E31 y Component.J 2 -1.0E31 z Component.K 3 -1.0E31 Positional GEI latitude GEI_LAT Latitude of the spacecraft position in GEI Deg Spherical GEI -90.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional GEI longitude GEI_LON Longitude of the spacecraft position in GEI Deg Spherical GEI -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional J2000 position XYZ_J2000 Spacecraft position in J2000 km 1e3>m Cartesian J2000 3 x Component.I 1 -1.0E31 y Component.J 2 -1.0E31 z Component.K 3 -1.0E31 Positional J2000 latitude J2000_LAT Latitude of the spacecraft position in J2000 Deg Spherical J2000 -90.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional J2000 longitude J2000_LON Longitude of the spacecraft position in J2000 Deg Spherical J2000 -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional GEO position XYZ_GEO Spacecraft position in GEO km 1e3>m Cartesian GEO 3 x Component.I 1 -1.0E31 y Component.J 2 -1.0E31 z Component.K 3 -1.0E31 Positional GEO latitude GEO_LAT Latitude of the spacecraft position in GEO Deg Spherical GEO -90.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional GEO longitude GEO_LON Longitude of the spacecraft position in GEO Deg Spherical GEO -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional GEO local time GEO_LCT_T hours 0.0 24.0 -1.0E31 DirectionAngle.AzimuthAngle Positional GM position XYZ_GM Spacecraft position in GM km 1e3>m Cartesian MAG 3 x Component.I 1 -1.0E31 y Component.J 2 -1.0E31 z Component.K 3 -1.0E31 Positional GM latitude GM_LAT Latitude of the spacecraft position in GM Deg Spherical MAG -90.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional GM longitude GM_LON Longitude of the spacecraft position in GM Deg Spherical MAG -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional GM local time GM_LCT_T hours 0.0 24.0 -1.0E31 DirectionAngle.AzimuthAngle Positional GSE position XYZ_GSE Spacecraft position in GSE km 1e3>m Cartesian GSE 3 x Component.I 1 -1.0E31 y Component.J 2 -1.0E31 z Component.K 3 -1.0E31 Positional GSE latitude GSE_LAT Latitude of the spacecraft position in GSE Deg Spherical GSE -90.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional GSE longitude GSE_LON Longitude of the spacecraft position in GSE Deg Spherical GSE -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional GSE local time GSE_LCT_T hours 0.0 24.0 -1.0E31 DirectionAngle.AzimuthAngle Positional GSM position XYZ_GSM Spacecraft position in GSM km 1e3>m Cartesian GSM 3 x Component.I 1 -1.0E31 y Component.J 2 -1.0E31 z Component.K 3 -1.0E31 Positional GSM latitude GSM_LAT Latitude of the spacecraft position in GSM Deg Spherical GSM -90.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional GSM longitude GSM_LON Longitude of the spacecraft position in GSM Deg Spherical GSM -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional SM position XYZ_SM Spacecraft position in SM km 1e3>m Cartesian SM 3 x Component.I 1 -1.0E31 y Component.J 2 -1.0E31 z Component.K 3 -1.0E31 Positional SM latitude SM_LAT Latitude of the spacecraft position in SM Deg Spherical SM -90.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional SM longitude SM_LON Longitude of the spacecraft position in SM Deg Spherical SM -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional SM local time SM_LCT_T hours 0.0 24.0 -1.0E31 DirectionAngle.AzimuthAngle Positional Space Region SPACECRAFT_REGIONS Region in space where the spacecraft is located. Values are: 1 = INTERPLANETARY_MEDIUM, 2 = DAYSIDE_MAGNETOSHEATH, 3 = NIGHTSIDE_MAGNETOSHEATH, 4 = DAYSIDE_MAGNETOSPHERE, 5 = NIGHTSIDE_MAGNETOSPHERE, 6 = PLASMA_SHEET, 7 = TAIL_LOBE, 8 = LOW_LATITUDE_BOUNDARY_LAYER, 9 = HIGH_LATITUDE_BOUNDARY_LAYER, 10 = DAYSIDE_PLASMASPHERE, 11 = NIGHTSIDE_PLASMASPHERE. 1 11 -2147483648 Scalar Other Radial Traced Footpoint Region RADIAL_TRACED_REGIONS Region on the Earth's surface where a straight line would intersect when connecting the spacecraft and the Earth's center. Values are: 0 = NOT_APPLICABLE, 1 = NORTH_CUSP, 2 = SOUTH_CUSP, 3 = NORTH_CLEFT, 4 = SOUTH_CLEFT, 5 = NORTH_AURORAL_OVAL, 6 = SOUTH_AURORAL_OVAL, 7 = NORTH_POLAR_CAP, 8 = SOUTH_POLAR_CAP, 9 = NORTH_MID_LATITUDE, 10 = SOUTH_MID_LATITUDE, 11 = LOW_LATITUDE. 0 11 -2147483648 Scalar Other North B Traced Footpoint Region NORTH_BTRACED_REGIONS Region on the Earth's surface where the magnetic field line that passes through the spacecraft intersects the Earth's surface in the Earth's northern magnetic hemisphere. Values are: 0 = NOT_APPLICABLE, 1 = NORTH_CUSP, 3 = NORTH_CLEFT, 5 = NORTH_AURORAL_OVAL, 7 = NORTH_POLAR_CAP, 9 = NORTH_MID_LATITUDE, 11 = LOW_LATITUDE. 0 11 -2147483648 Scalar Other South B Traced Region SOUTH_BTRACED_REGIONS Region on the Earth's surface where the magnetic field line that passes through the spacecraft intersects the Earth's surface in the Earth's southern magnetic hemisphere. Values are: 0 = NOT_APPLICABLE, 2 = SOUTH_CUSP, 4 = SOUTH_CLEFT, 6 = SOUTH_AURORAL_OVAL, 8 = SOUTH_POLAR_CAP, 10 = SOUTH_MID_LATITUDE, 11 = LOW_LATITUDE. 0 11 -2147483648 Scalar Other Radial Distance RADIUS Radial distance of the spacecraft km 1e3>m Spherical GEO 0.0 -1.0E31 Magnitude Positional Magnetic Field Strength MAG_STRTH Model predicted magnetic field strength nT 0.0 -1.0E31 Magnetic Dipole L Value L_VALUE Mcllwain L value at the spacecraft's location 1.5 5.0 -1.0E31 Positional Dipole Invariant Lattitude INVAR_LAT Dipole invariant latitudes at the spacecraft's location Deg -90.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional Distance to neutral sheet DNEUTS Distance from satellite to neutral sheet Km 0.0 -1.0E31 Scalar Positional Distance to bow shock BOW_SHOCK Distance from satellite to bow shock Km 0.0 -1.0E31 Scalar Positional Distance to magnetopause MAG_PAUSE Distance from satellite to magnetopause Km 0.0 -1.0E31 Scalar Positional Magnetic Field Strength along the GSE X axis MAG_X Model predicted magnetic field strength along the GSE X axis nT 0.0 -1.0E31 Component.I Magnetic Magnetic Field Strength along the GSE Y axis MAG_Y Model predicted magnetic field strength along the GSE Y axis nT 0.0 -1.0E31 Component.J Magnetic Magnetic Field Strength along the GSE Z axis MAG_Z Model predicted magnetic field strength along the GSE Z axis nT 0.0 -1.0E31 Component.K Magnetic North Hemisphere B Trace GEO latitude NorthBtrace_GEO_LAT Latitude of the northern magnetic field traced footpoint in GEO Deg Spherical GEO 0.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional North Hemisphere B Trace GEO longitude NorthBtrace_GEO_LON Longitude of the northern magnetic field traced footpoint in GEO Deg Spherical GEO -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional North Hemisphere B Trace GEO arc length NorthBtrace_GEO_ARCLEN Length of the magnetic field traced arc from the spacecraft to the northern footpoint in GEO Km 0.0 -1.0E31 Scalar Other South Hemisphere B Trace GEO latitude SouthBtrace_GEO_LAT Latitude of the southern magnetic field traced footpoint in GEO Deg Spherical GEO -90.0 0.0 -1.0E31 DirectionAngle.ElevationAngle Positional South Hemisphere B Trace GEO longitude SouthBtrace_GEO_LON Longitude of the southern magnetic field traced footpoint in GEO Deg Spherical GEO -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional South Hemisphere B Trace GEO arc length SouthBtrace_GEO_ARCLEN Length of the magnetic field traced arc from the spacecraft to the southern footpoint in GEO Km 0.0 -1.0E31 Scalar Other North Hemisphere B Trace GM latitude NorthBtrace_GM_LAT Latitude of the northern magnetic field traced footpoint in GM Deg Spherical MAG 0.0 90.0 -1.0E31 DirectionAngle.ElevationAngle Positional North Hemisphere B Trace GM longitude NorthBtrace_GM_LON Longitude of the northern magnetic field traced footpoint in GM Deg Spherical MAG -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional North Hemisphere B Trace GM arc length NorthBtrace_GM_ARCLEN Length of the magnetic field traced arc from the spacecraft to the northern footpoint in GM Km 0.0 -1.0E31 Scalar Other South Hemisphere B Trace GM latitude SouthBtrace_GM_LAT Latitude of the southern magnetic field traced footpoint in GM Deg Spherical MAG -90.0 0.0 -1.0E31 DirectionAngle.ElevationAngle Positional South Hemisphere B Trace GM longitude SouthBtrace_GM_LON Longitude of the southern magnetic field traced footpoint in GM Deg Spherical MAG -180.0 360.0 -1.0E31 DirectionAngle.AzimuthAngle Positional South Hemisphere B Trace GM arc length SouthBtrace_GM_ARCLEN Length of the magnetic field traced arc from the spacecraft to the southern footpoint in GM Km 0.0 -1.0E31 Scalar Other