On a display on the Defiant
A long range sensor scan or long range scan is a scan which allows the person to search a large area in space for something like starships.
In 2369 Worf informed Commander William T. Riker that the long range sensors of the Enterprise-D picked up a distress call from a Romulan warbird. Later Geordi was unable to find the Enterprise-D which was not at the rendezvous point. He told Captain Picard that the long range sensors are at maximum and there was no sign of the Enterprise-D. (TNG: "Timescape")
In 2370, Sam Lavelle performed a long range scan to find the escape pod near the Cardassian border, but without any result. Data suggested it is possible that at this distance the sensors of the USS Enterprise-D are unable to distinguish the pod from the inorganic matter normally present in space. (TNG: "Lower Decks")
In an alternate timeline, Data, on board the USS Pasteur, performed a long range sensor scan to locate anomalies in the Devron system but found nothing. (TNG: "All Good Things...")
In 2372 Lieutenant Commander Worf performed a long range sensor scan from a console on the bridge of the USS Defiant. He searched for Klingon starships. (DS9: "The Way of the Warrior")