Class Name: GSM Location 3D

Superclass - Location 3D

Definition

A coordinate within the Geocentric Solar Magnetic (GSM) 3D Spatial Reference Frame (SRF).

The Geocentric Solar Magnetic Spatial Reference System, also known as Solar Magnetospheric (SMC), is based on a Cartesian coordinate system with 3 orthogonal axes and an origin at the mass-center of the Object Reference Model/Earth Reference Model (ORM/ERM) as defined by the World Geodetic System (WGS) 1984 ellipsoid. The X axis is defined as pointing in the direction of the Sun and is in the Geomagnetic Equatorial plane. The Z axis is defined as perpendicular to the X axis, in the plane containing the X axis and the Geomagnetic dipole (axis), and pointing north. The Y axis is defined as orthogonal to the other two and lying in the Geomagnetic Equatorial plane, so as to form a right-handed orthogonal set.

Locations are defined as {lon, lat, r} triplets from the origin (ORM/ERM mass-center). Longitude (lon) is defined as the geocentric angle measured eastward along the intersection of the Geomagnetic Equatorial plane, with the ORM/ERM surface from the noon meridian to the local meridian containing the radius vector. Latitude (lat) is defined as the geocentric angle between the radius vector and the Geomagnetic Equatorial plane; it is positive towards the north. R is the magnitude of the radius vector.

See the SEDRIS Spatial Reference Model (SRM) for additional details.

Primary Page in DRM Diagram:

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Example

GSM provides a convenient system for displaying

1. magnetopause and shock boundary positions
2. magnetosheath and magnetotail fields
3. magnetosheath solar wind velocities (since the orientation of the magnetic dipole axis alters the otherwise cylindrical symmetry of the solar wind flow).

FAQs

What kind of data is ordinarily represented in GSM?

GSM is quasi-inertial in that it rocks about the solar direction on both yearly (23.4 degrees +- 11.2 degrees) and 24 hour (+- 11.2 degree) cycles.

Constraints

• Environment Root Spatial Reference Frame
• Locations Under Model

Component of (one-way)(inherited)

• optionally, some Arcs
• optionally, some Base Perimeter Data
• optionally, some Base Reference Vectors
• optionally, some Directional Light Behaviors
• optionally, a Distance Level of Detail Data (notes)
• optionally, some Ellipses
• optionally, some Elliptic Cylinders
• optionally, some Feature Edges
• optionally, a Feature Node
• optionally, some Image Anchors
• optionally, some Labels
• optionally, a Location Table
• optionally, some Morph Points
• optionally, some Point Geometries
• optionally, some Property Grid Hook Points
• optionally, a Reference Origin
• optionally, some Spatial Domains
• optionally, some Spatial Index Related Feature Topologies
• optionally, some Spatial Index Related Features
• optionally, some Spatial Index Related Geometries
• optionally, some Tack Points
• optionally, some Vertices
• optionally, some Vertex with Component Indices
• optionally, some World 3X3s
• optionally, some World Transformations
• optionally, an Attachment Point
• optionally, some Center of Buoyancies
• optionally, some Center of Mass
• optionally, some Center of Pressures
• optionally, a Contact Point
• optionally, some Positional Lights
• optionally, some Separating Planes
• optionally, some Sound Instances
• optionally, some Stamp Behaviors
• optionally, some Volumes
• optionally, some Volume Level of Detail Data
• optionally, some Volume Light Behaviors

Field Elements

Notes

Component of Notes

Distance_Level_of_Detail_Data

 the center point for the LOD test

Fields Notes

longitude

 in degrees

latitude

 in degrees

radius

 in meters