Module angles 

Angular geometry helpers for sky directions and satellite body geometry.

Computes general angular separation between arbitrary directions or (lon, lat) / (RA, Dec) pairs, position angle measured North through East, and satellite nadir/Sun, nadir/Moon, Sun-elevation, phase, solar beta, and Earth angular radius angles. Public angle-producing helpers in this module return degrees unless their names state otherwise.

Enums

AngleError

Error while computing satellite angular geometry.

Functions

angular_separation

On-sky angle (degrees) between two direction vectors, via the stable atan2(|a x b|, a . b) form.

angular_separation_coords

On-sky angle (degrees) between two (lon, lat) / (RA, Dec) pairs in degrees. The second tuple component is the latitude or declination in [-90, 90].

beta_angle

Solar beta angle (degrees, signed, in [-90, 90]): the elevation of the Sun above the orbit plane, beta = 90 - angle(orbit_normal, sun), computed in the normative pi/2 - acos(clamp(cos)) operation order.

beta_angle_from_state

Solar beta angle (degrees) from an inertial Cartesian state.

earth_angular_radius

Angular radius (degrees) of the Earth as seen from the satellite: asin(R_earth / |sat_pos|), clamped to the asin domain.

moon_angle

Angle (degrees) between satellite nadir and the Moon direction.

normalize_geodetic_lon_rad

Snap a geodetic longitude (radians) off the -pi branch cut onto +pi.

phase_angle

Sun-satellite-observer phase angle (degrees): the angle at the satellite between the Sun and the observer.

position_angle

Position angle (degrees, [0, 360)) of to as seen from from, measured from North (+lat) through East (+lon). Inputs are (lon, lat) in degrees.

rad_to_deg_ref

Radians to degrees in the reference operation order (rad * 180 / pi, multiply before divide), required for bit-exact parity with the prior Elixir reference rather than a single rounded RAD_TO_DEG constant.

sun_angle

Angle (degrees) between satellite nadir and the Sun direction.

sun_elevation

Sun elevation (degrees) above the satellite’s local horizontal plane.