Group 1 - The Shenzhou-20 mission has completed its final comprehensive rehearsal before launch, with all systems checked and personnel ready [1][3][12] - This rehearsal is the last full-scale practice closely simulating the actual launch process [3] - The mission includes a unique passenger, the planarian, known for its remarkable regenerative abilities [3][5] Group 2 - The planarian, specifically the East Asian three-striped planarian, is a model organism in biological research due to its powerful regeneration capabilities [7] - Research on planarians aims to explore the effects of the space environment on regeneration processes and physiological changes, potentially revealing molecular mechanisms [9][10] - The experiments conducted in the Chinese space station are expected to provide critical insights for future space medicine and human cell aging research [10][12]