Rainer
Ensign Rainer was a Starfleet tactical officer serving aboard the  in 2370. 

He was assigned to the night watch and was on duty while Doctor Beverly Crusher substituted for Lieutenant Commander Data, who was retrieving fragments from a crashed Federation deep space probe on the planet Barkon IV. Rainer attempted to hail Data and inform him of a delay in the planned rendezvous with the Enterprise-D, but was unable to contact him. When he informed Crusher of this,
she ordered him to continue updating Data on their schedule. ()

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Humans
Starfleet operations personnel
USS Enterprise (NCC-1701-D) personnel