2026RNAAS..10....5J

Using the Vera C. Rubin Observatory Data Preview 1, we present the detection and photometric analysis of a stellar stream extending along the minor axis of a massive disk-galaxy, LEDA 751050, at a redshift of z = 0.1 in the Extended Chandra Deep Field-South. This feature appears to be an analog of the M31 Giant Stellar Stream, spanning around 130 kpc by 15 kpc, with an estimated stellar mass of M_⋆ = 6 × 10⁸M_⊙, and a mean g-band surface brightness (SB) of μ_g = 28.6 mag arcsec^–2. This discovery demonstrates Rubin's ability to reveal low-SB substructures and foreshadows the future capabilities when the full Legacy Survey of Space and Time dataset is actualized.