An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

Pertaining to, or founded on observation, especially based on observation rather than theory.

Adj. of → observation.

That part of astrophysics that is mainly concerned with the collection of observational data, in comparison with theoretical astrophysics

→ observational; → astrophysics.

An error in observation arising from systematically favoring brighter or weaker objects or some particular object morphologies; e.g. → Malmquist bias.

→ observational; → bias.

The application of observational data to the study of the Universe as a whole.

→ observational; → cosmology.

A feature appearing in an observation, which is not intrinsic to the object observed, but is due to the inappropriate method used (e.g. limited angular resolution).

→ observational; → effect.

The difference between a measured value of quantity and its true value.

→ observational; → error.