Visible Light Has Been Detected From Black Holes For The First Time

A Nasa illustration of a supermassive black hole. Before the V404 Cygni observations, similar outbursts had only been seen as intense flashes of x-rays and gamma-rays, using high-spec telescopes. Photograph: Nasa/Reuters

The Guardian: Visible light from black holes detected for first time

Scientists observing V404 Cygni discovered that even amateur telescopes are capable of capturing violent outburst from black holes closest to Earth.

Astronomers have discovered that black holes can be observed through a simple optical telescope when material from surrounding space falls into them and releases violent bursts of light.

The apparent contradiction emerges when a black hole’s gravity pulls in matter from nearby stars, producing light that can be viewed from a modest 20cm telescope.

Japanese researchers detected light waves from V404 Cygni - an active black hole in the constellation of Cygnus, the Swan - when it awoke from a 26-year-long slumber in June 2015.

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CSN Editor: More proof that black holes do exist.

Did 'Dark Stars' Spawn Supermassive Black Holes?

A massive dark star voraciously eating matter and dark matter until it is well over 100,000 times the mass of the sun (NASA/Ian O'Neill).

From Discover Magazine:

Approximately 200 million years after the Big Bang, the universe was a very different place.

For starters, there was no starlight as there were no stars. This period was known descriptively as the "Dark Ages." As there were no stars, only clouds of the most basic elements persisted, fogging up the cosmos.

Although it's believed the first stars (known as "Population III stars") were sparked when hydrogen and helium gases cooled enough to clump together, collapsing under gravity and initiating nuclear fusion in the star cores (thus generating heavier elements), there's another possibility.

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Suzaku Catches Retreat Of A Black Hole's Disk

Image: GX 339-4, illustrated here, is among the most dynamic binaries in the sky, with four major outbursts in the past seven years. In the system, an evolved star no more massive than the sun orbits a black hole estimated at 10 solar masses. (Credit: ESO/L. Calçada)

From Science Daily:

ScienceDaily (Dec. 12, 2009) — Studies of one of the galaxy's most active black-hole binaries reveal a dramatic change that will help scientists better understand how these systems expel fast-moving particle jets.

Binary systems where a normal star is paired with a black hole often produce large swings in X-ray emission and blast jets of gas at speeds exceeding one-third that of light. What fuels this activity is gas pulled from the normal star, which spirals toward the black hole and piles up in a dense accretion disk.

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