After refueling finished last week, this time Tianzhou-1 robotic cargo spacecraft and Tiangong-2 space station separated for five hours to perform rendez vous maneuver.
Tianzhou-1 conducted correct separation yesterday. Maneuver was performed completely without any engagement from Earth - both Tianzhou-1 and Tiangong-2 were relying only on their onboard computers during whole process. After releasing bolts at 01:37 UTC cargo spacecraft was gently pushed away from station by set of springs. It was beginning of the maneuver lasting for five hours for both vehicles. As Tianzhou-1 begun its retreat from Tiangong-2, station was keeping during whole 180 degree flyaround its docking port facing the Tianzhou-1.
Whole maneuver was conducted after Tianzhou-1 reached distance of 5 km from Tiangong-2. Cargo spacecraft remain 90 minutes on this distance controlling it with radio and laser guided navigation system. After 90 minutes Tianzhou-1 begun its approach to Tiangong-2 with onboard thrusters. After another hours it finally reached station's docking port at 05:55 UTC and docked securely.
Tianzhou-1 mission started on April 20th and will finish after five months, probably in September 2017.