Inertial (non rotating) 3D cartesian coordinate reference system with its origin at the earth's center of mass and based on the M50 reference frame
https://www.opengis.net/def/crs/OGC/0/ECI_M50
https://www.opengis.net/def/crs/OGC/0/ECI_M50
Earth-Centered Intertial, M50
All 3D space inside, on the surface, or around the earth, usually within the limits of the solar system
Earth centered, inertial, righthanded 3D cartesian coordinate system
https://www.opengis.net/def/cs/OGC/0/ECI
https://www.opengis.net/def/cs/OGC/0/ECI
Earth-Centered Intertial
https://www.opengis.net/def/axis/OGC/0/ECI-X
X
Aligned with the the vernal equinox (intersection of the ecliptic and the earth's equatorial plane), and directed so that it points to the sun around March 21st
https://www.opengis.net/def/axis/OGC/0/ECI-Y
Y
On the plane of the celestial equator, orthogonal to both X and Z, so that the frame is right handed
https://www.opengis.net/def/axis/OGC/0/ECI-Z
Z
Aligned with the earth spin axis, in the direction of the celestial north pole
M50 datum for ECI frames
https://www.opengis.net/def/crs/OGC/0/DATUM_M50
Universe
M50 frame anchored at the earth's center of mass and defined with the earth's mean equator and equinox at 12:00 terrestrial time on 1st January 1950
1950-01-01