Combined effects of spectral and spatial resolution on CGM kinematic observability for the Maelstrom halo using O VI emission. Each row corresponds to a different spatial resolution (0.18, 1, 3, and 6 kpc, which correspond at z = 0.5 (z = 0) to ∼ 0.04 (5.6), 0.16 (20), 0.5 (61), and 1 (120) arcsec, respectively). Left column: maps of absolute projected velocity differences (Δv) between inflowing and outflowing gas (defined as v_rad < − 100 km s⁻¹ and v_rad > 200 km s⁻¹, respectively). Gray pixels are unresolved (Δv < 30 km s⁻¹); colored pixels indicate increasing Δv detectable at different kinematic resolutions: blue-purple (30–100 km s⁻¹), purple-orange (100–200 km s⁻¹), and orange-yellow (>200 km s⁻¹). Middle column: surface brightness maps showing detectable regions above a sensitivity threshold of 100 photons s⁻¹ cm⁻² sr⁻¹ (cyan, purple, and yellow). Right column: pixels that are resolved in both surface brightness and velocity (using Δv = 30 km s⁻¹ and SB=100 photons s⁻¹ cm⁻² sr⁻¹ thresholds), color coded by velocity difference. This panel shows how improved kinematic resolution enables separation of inflows and outflows in regions already observable in emission. At 30 km s⁻¹ resolution, over 90% of the emission-resolved gas can be kinematically distinguished; at 200 km s⁻¹, this fraction drops to ∼40%–50%.