Radio and optical specific intensity function details around the SDSS DR12 source J081421.68+522410.0, Alcyoneus’s host galaxy. The panels cover a 2.5′×2.5′ region around the host, an elliptical galaxy with spectroscopic redshift z_spec = 0.24674  ±  6 × 10⁻⁵. From top to bottom: we show the LoTSS DR2 6″, the VLASS 2.2″, and the Pan-STARRS DR1 i band relative to the host’s specific intensity with LoTSS contours (white) as in Fig. 3 and a VLASS contour (gold) at 5σ.