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marketrent OP t1_j31n5cf wrote

Andrea Gianopoulos, 4 Jan. 2023, NASA.

Excerpt:

>In giant clusters of hundreds or thousands of galaxies, innumerable stars wander among the galaxies like lost souls, emitting a ghostly haze of light. These stars are not gravitationally tied to any one galaxy in a cluster.

>The nagging question for astronomers has been: how did the stars get so scattered throughout the cluster in the first place?

>A recent infrared survey from NASA's Hubble Space Telescope, which looked for this so-called "intracluster light," sheds new light on the mystery.

>The new Hubble observations suggest that these stars have been wandering around for billions of years, and are not a product of more recent dynamical activity inside a galaxy cluster that would strip them out of normal galaxies.

>The survey included 10 galaxy clusters as far away as nearly 10 billion light-years. These measurements must be made from space because the faint intracluster light is 10,000 times dimmer than the night sky as seen from the ground.

>The survey reveals that the fraction of the intracluster light relative to the total light in the cluster remains constant, looking over billions of years back into time.

>"This means that these stars were already homeless in the early stages of the cluster's formation," said James Jee of Yonsei University in Seoul, South Korea.

Nature, 4 Jan. 2023, DOI: 10.1038/s41586-022-05396-4

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jonathanrdt t1_j331dz6 wrote

Would the night sky on a world orbiting such a star be fundamentally different? It would be mostly black, wouldn’t it?

Edit: Copied text from the link below:

>They could see the nebulae, beautiful and distant and beckoning, and could tell that those faraway galaxies were composed of suns, other stars like Thrial, and even guess that some of those suns too might have planets round them… but they looked in vain for stars anywhere near their own.

>The sky was full of darkness. There were planets and moons and the tiny feathery whorls of the dim nebulae, and they had themselves filled it with junk and traffic and emblems of a thousand different languages, but they could not create the skies of a planet within a galaxy, and they could not ever hope, within any frame of likelihood they could envisage existing, to travel to anywhere beyond their own system, or the everywhere-meaningless gulf of space surrounding their isolated and freakish star.

>For a distance that was never less than a million light years in any direction around it, Thrial-for all its flamboyant dispersion of vivifying power and its richly fertile crop of children planets-was an orphan.

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018118055 t1_j33aser wrote

This is a fictional account of such a situation from the book Against a Dark Background by Iain M. Banks.

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