Kippenhahn diagrams showing the evolution of the interior of the Sun with and without a central BH. The left panels show the mass distribution, with regions of energy generation and transport indicated. The right panels show the radial distribution, with the radius of the photosphere (black line) and the solar radius (horizontal dashed line) indicated. The top panels correspond to a normal solar evolution model evolved through the MS until core hydrogen exhaustion and up through hydrogen shell burning as a red giant. The bottom panels show a model that is consistent with the present Sun with a BH growing at its center. Nuclear fusion (red) provides the bulk of the solar luminosity until the BH is of sufficient mass to quench the reactions. The BH drives convection (hatches), which mixes the innermost parts of the core, and eventually the entire star. Note the differences in the y-axis scale between the panels. Credit: The Astrophysical Journal (2023). DOI: 10.3847/1538-4357/ad04de