Discovery of Optical Filaments in the North Polar Spur/eROSITA Bubble

I report the discovery of optical filaments in H alpha, [O III], and [S II], coincident with 144, MHz structure, associated with the North Polar Spur (NPS) region of the eROSITA bubbles. The optical emission is identified in the Northern Sky Narrowband Survey, and contains distinct structure and potentially elevated[S II]/H alpha relative to typical high- b outflows from the warm ionized medium (WIM). -variance and power spectrum analysis of the NPS H alpha shows a preference for filaments on the scale of lag L about0.6. The optical and 144, MHz emission peaks in intensity in an interior region of the NPS, aligned with surrounding Galactic magnetized structures, and also shows fainter signal at the eROSITA bubble edge. The required power to produce the background-subtracted I H alpha=1.85 plus or minus1.04, R emission is P req about5-12 times10 41, erg,s-1, comfortably exceeded by AGN jet models, plausible for AGN hot accretion flow and star formation ring models, and disfavoring star formation driven winds.