Tiangong: Expedition 7

Expedition 7 began with undocking of Shenzhou-17 on April 30, 2024 at 00:43 UTC.

t the beginning of their stay, the astronauts installed an aquarium with four zebrafish. This is a closed ecosystem in which the plants were fertilized with the fish's feces. The plants produce the oxygen needed for the fish. The aquarium contained a pump to circulate water between the plant and fish areas. A sensor in the fish compartment reported when the oxygen level fell below the threshold and switched on a lamp. This triggered photosynthesis.
After 20 days, the fish were still disoriented, but they were doing so well that they spawned after mating. The spawn was collected by the astronauts and frozen for study on Earth.

The unmanned freighter Tianzhou-7 docked with the space station on January 17, 2024. On board were, among other things, materials needed for the production of fiber optic cables.

As a result of strong solar storms, the apogee and perigee of Tiangong had dropped and had to be raised using the engines of Tianzhou-7.

On May 28, 2024 Ye Guangfu and Li Guangsu performed the first spacewalk (8h 23m). Main tasks were the Installation of micrometeorite shields and inspecting equipment outside the spacecraft with precise coordination.
To achieve a range of 14.5 meters, the two robotic arms were coupled together. Ye Guangfu was taken to the solar cell flights with the mechanical arm. Li Guangsu later climbed along Wentian's outer wall to the solar cells. He examined them for damage and discovered discoloration and small craters.

Shenzhou-18 astronauts Ye Guangfu and Li Cong completed the second spacewalk on July 03, 2024 at 14:58 UTC on July 03, 2024. More debris shields on Wentian were installed and checked solar arrays. The spacewalk lasted 6h 39m.

About two weeks after the EVA, a leak with pressure loss caused by space debris was simulated as part of an exercise. Contrary to a previous exercise, the crew searched for the leak. Astronauts Li Guangsu and Li Cong, equipped with tools and wearing breathing masks, searched for the simulated leak, while Ye Guangfu monitored the operation from the Tianhe core module.

A test of the smoke and fire detectors was conducted in the first week of August 2024. An evacuation drill followed one week later.

Expedition 7 concluded with undocking of Shenzhou-17 on November 03, 2024.