Shadows in space?

This Hubble Space Telescope image of the heart of the active galaxy IC 5063, 156 million light-years from Earth, reveals a mixture of bright rays and dark shadows coming from its blazing core, the home of a supermassive black hole.

Astronomers suggest that a ring of dusty material surrounding the black hole may be casting its shadow into space.

According to their scenario, this interplay of light and shadow may occur when light blasted by the monster black hole strikes the dust ring, which is buried deep inside the core. Light streams through gaps in the ring, creating the brilliant cone-shaped rays. However, denser patches in the disc block some of the light, casting long, dark shadows through the galaxy.

This phenomenon is similar to sunlight piercing Earthly clouds at sunset – such as in the image below from Grand Tetons National Park in the US – creating a mixture of bright rays and dark shadows formed by beams of light scattered by the atmosphere. The darker regions represent the clouds casting shadows where sunlight could not pass through.

The big difference, of course, is that the bright rays and dark shadows appearing in IC 5063 are happening on a much larger scale – shooting across at least 36,000 light-years.

It’s usually pretty near impossible to discern any details at these kind of distance, but what NASA calls “a quirk of alignment” allowed astronomers to get a glimpse of the structure of the disc around the black hole in this relatively nearby galaxy.

201121 sunset
Credit: Z Levay

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