Four zebrafish launched to the China Space Station during the Shenzhou-18 mission last month are thriving, according to a video obtained by China Media Group. However, the fish appear to be experiencing some challenges with spatial orientation.

Taikonauts residing on the station have reported observing the fish occasionally swimming upside down, making circular motions, or even spinning for the past three weeks.

Scientists involved in China's human spaceflight program are closely monitoring this unusual behavior to gain insight into the development of vertebrates in microgravity. Their goal is to establish a self-sustaining ecosystem within a confined space environment.

The Shenzhou-18 manned spacecraft was launched in late April, sending three taikonauts to the China Space Station for a half-year stay.