GIOTTO Ephemeris: P1/Halley FlyBy

GIOTTO Ephemeris data are calculated using SPICE kernels taken from the NAIF


Coordinates :


• HCI: Heliocentric Inertial Frame - All vectors are geometric: no aberration corrections are used. The solar rotation axis is the primary vector: the Z axis points in the solar north direction. The solar ascending node on the ecliptic of J2000 forms the X axis. The Y axis is Z cross X, completing the right-handed reference frame.
• HEE : Heliocentric Earth Ecliptic Frame - All vectors are geometric: no aberration corrections are used. The position of the Earth relative to the Sun is the primary vector: the X axis points from the Sun to the Earth. The northern surface normal to the mean ecliptic of date is the secondary vector: the Z axis is the component of this vector orthogonal to the X axis. The Y axis is Z cross X, completing the right-handed reference frame.
• HEEQ : Heliocentric Earth Equatorial Frame - All vectors are geometric: no aberration corrections are used. The solar rotation axis is the primary vector: the Z axis points in the solar north direction. The position of the Sun relative to the Earth is the secondary vector: the X axis is the component of this position vector orthogonal to the Z axis. The Y axis is Z cross X, completing the right-handed reference frame.
• CSO The body-Centered Solar Orbital frames for the GIOTTO target comet P1/Halley, is named 'P1/H_CSO' This frame is defined as a two-vector style dynamic frames as follows: - The position of the sun relative to the body is the primary vector: the X axis points from the body to the sun. - The inertially referenced velocity of the sun relative to the body is the secondary vector: the Y axis is the component of this velocity vector orthogonal to the X axis. - The Z axis is X cross Y, completing the right-handed reference frame. - All vectors are geometric: no aberration corrections are used.