RAAN & the ascending node
The ascending node is where a satellite crosses the equator heading north; RAAN (right ascension of the ascending node) is the angle that fixes that crossing point in space.
Together with inclination, RAAN orients the orbital plane, setting which ground tracks the satellite will follow.
Earth's equatorial bulge slowly rotates the RAAN over time — an effect that sun-synchronous orbits deliberately harness.
See it live on Cosmik
Related terms
- Orbital inclination — Orbital inclination is the angle between a satellite's orbital plane and Earth's equator, measured in degrees.
- Sun-synchronous orbit — A sun-synchronous orbit (SSO) is a near-polar low Earth orbit tuned so the satellite passes over every location at the same local solar time on each visit.
- Ground track — A ground track is the path traced on Earth's surface directly beneath a satellite as it orbits.
