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Instrument Pointing

Instrument pointing and rotational rates.

View the source on GitHub

Properties

* = required

NameTypeDescription
ra_pointingnumberRA pointing of the instrument Z axis. ICRS declination [deg], utilizes the J2000 epoch and an equatorial coordinate system.
dec_pointingnumberDec pointing of the instrument Z axis. ICRS declination [deg], utilizes the J2000 epoch and an equatorial coordinate system.
rollnumberRoll [deg] of the instrument about its Z axis
position_anglenumberRotation angle [deg] between the spacecraft X-Z plane and the plane defined by the spacecraft X-axis and celestial North
attitude_quarternionarrayRepresenting attitude state of a spacecraft, using four element vector [q1, q2, q3, q4], composed of a scalar and 3 element unit vector.
rotation_ratearrayRotational rate [rad/s] about the X, Y, and Z axes respectively
timestringTime [UTC, ISO 8601] of this data, if different than the trigger time.

Example

{
  "$schema": "https://gcn.nasa.gov/schema/v4.2.0/gcn/notices/core/Pointing.schema.json",
  "ra_pointing": 120.5,
  "dec_pointing": 30.2,
  "roll": -12.8,
  "position_angle": 23.7,
  "attitude_quarternion": [
    0.2,
    0.3,
    0.4,
    0.5
  ],
  "rotation": [
    -0.01,
    0.05,
    0.02
  ],
  "time": "2022-05-08T13:30:00Z"
}
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