CL_gm_raan2beta

Description

• Computes the beta angle (angle between the orbit plane and the Sun direction) form the right ascension of the ascending node.

  

• Note:

  - The beta angle is a signed quantity. If it is positive then the Sun direction is less than 90 degrees from the orbit's angular momentum vector (vector perpendicular to the orbit plane and oriented according to right hand rule).

  - Be careful about the order of arguments: inclination, raan...

Parameters

inc:

Orbit inclination [rad] (1xN)

raan:

Orbit right ascension of ascending node [rad] (1xN)

alpha_sun:

Sun right ascension [rad] (1xN)

delta_sun:

Sun declination [rad] (1xN)

betaa:

Beta angle [rad] (1xN)

See also

• CL_gm_beta2raan

Authors

• CNES - DCT/SB

Examples

// Get alpha_sun and delta_sun cjd = 20050; pos_sun = CL_eph_sun(cjd); pos_sun_sph = CL_co_car2sph(pos_sun); alpha_sun = pos_sun_sph(1); delta_sun = pos_sun_sph(2); raan = %pi/4; inc = CL_deg2rad(98.7); betaa = CL_gm_raan2beta(inc,raan,alpha_sun,delta_sun)