Most stars are born in clusters, yet direct observational evidence linking neutron stars in the Galactic field to their birth clusters has long been missing. An international team led by Chinese scientists has identified the pulsar PSR J1921+3745 within the tidal tail of the 8-billion-year-old open cluster NGC 6791. FAST detected the pulsar, MeerKAT pinpointed its position, and CFHT mapped the surrounding stellar structure. Combined with direct N-body simulations, these observations show how a low-kick neutron star can remain bound to its host cluster for billions of years before being gradually stripped into the Galactic field. The result provides the first direct observational evidence of a neutron star in the tidal tail of an open cluster, revealing a key stage in the migration of neutron stars from their birth clusters into the Milky Way