This image of the core of the nearby spiral galaxy M51, taken with the Wide Field Planetary Camera shows a striking, dark "x" silhouetted across the galaxy's nucleus. The "x" is due to absorption by dust and marks the exact position of a suspected black hole which may have a mass equivalent to one million stars like the Sun. The darkest bar may be an edge-on dust ring which is 100 light-years in diameter. The edge-on torus not only hides the black hole and accretion disk from being viewed directly from Earth, but also determines the axis of a jet of high speed plasma and confines radiation from the accretion disk to a pair of oppositely directed cones of light, which ionize gas caught in their beam. The second bar of the "x" could be a second disk seen obliquely, or possibly rotating gas and dust in M51 interacting with the jets and ionization cones.
Image use statement at the time this image was obtained.
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