Chief science officer

The Chief Science Officer was a Starfleet senior staff position aboard a starship or starbase with the broad responsibility of coordinating the science department of the post. The officer served as the advisor to the command staff regarding questions of science, such as spatial phenomenon and unknown energy forces.

Duties & Functions
The chief science officer presided over all science missions performed by the starship and all projects aboard starships or stations. Science officers, including visiting science teams, of the starship or station operated under the chief science officer. The officer would coordinate with the chief medical officer when confronted with new lifeforms and biological phenomena.

Not all Starfleet vessels had science officers and on those vessels, science duties were delegated to the Chief operations officer. However, scientific research vessels and larger exploration starships have large science departments and the commanding and executive officers were usually science specialists in their own right. Federation starships sent on exploration missions always have a team of science officers overseen by a chief science officer.

Ranks
Chief science officers usually held the rank of Lieutenant or above.