Spinning Black Holes in Astrophysical Environments.

We present stationary and axially symmetric black hole solutions to the Einstein field equations sourced by an anisotropic fluid, describing rotating black holes embedded in astrophysical environments. We compute their physical properties, including quantities associated with the circular geodesics of massless and massive particles, analyze their shadows and image features, and analyze their energy conditions. Overall, we find that deviations from the Kerr metric grow with spin.