Figure 12-43 Supermassive Black Hole The bright region in the center of galaxy M87 has stars and gas held in tight orbits by a black hole. M87’s bright nucleus (center of the region in the white box) is only about the size of the solar system but it pulls on the nearby stars with so much force that astronomers calculate that it is a 3 × 109 M⊙ black hole. One of the bright jets of gas shooting out perpendicular to the black hole’s accretion disk (discussed in Section 12–14) is visible at the upper right on this image.