Astrometry
Measurement of a star's posiition plane-of-sky variations provides complimentary (as well as redundant) information to radial velocity measurements. The complimentary data which is obtained is the true inclination and the orientation of the planet's orbit.Astrometric orbits can be described in terms of the Thile-Innes constants, which are a function of:
- ω*, the argument of periastron of the star measured from the ascending node,
- i, the orbital inclination,
- Ω, the longitude of the ascending node, and
- Θ*, the semi-amplitude of the astrometric signal
...more to come....
Other detection methods:
Radial velocity
Direct imaging
Transits, and
Gravitational microlensing
