# HOW-TO Derive an astrometric solution¶

Astrometric solutions in AWE can be done in two different ways: on a chip-by-chip basis and globally (multiple chips at once). For the single-chip solution, an AstrometricParametersTask is used, and for the multi-chip solution, both GAstromSourceListTask and GAstromTask are used. See the appropriate HOW-TO section for instructions on how to do these: