first evidence of winds outside black holes throughout their mealtimes

New research shows the first evidence of strong winds around black holes throughout bright outburst events when a black hole rapidly consumes mass.

The study, published in Nature, sheds new light on how mass transfers to black holes and how black holes can affect the environment around them. The research was conducted by an international team of researchers, led by scientists in the University of Alberta's Department of Physics.

Using data from three international space agencies spanning 20 years, the scientists used new statistical techniques to study outbursts from stellar-mass black hole X-ray binary systems. Their results show evidence of consistent and strong winds surrounding black holes throughout outbursts. Until now, strong winds had only been seen in limited parts of these events.

"Winds must blow away a large fraction of the matter a black hole could eat,'' described Bailey Tetarenko, PhD student and lead author on the study. "In one of our models, the winds removed 80 per cent of the black hole's potential meal."

Source

 

Credit: NASA/Swift/A. Simonnet, Sonoma State University

Artistic rendition of strong winds disrupting the outer disc of material surrounding a stellar-mass black hole. The disk material (mostly in yellow) is first pulled from the outer parts of a nearby star (upper right-hand). The stellar-mass black hole sits at the center of the approximately 5 million kilometer disc, but it only consumes the material if and when it reaches the central 30 kilometers.

Source / Image Courtesy

Observations using ESO’s Very Large Telescope have revealed stars forming within powerful outflows of material blasted out from supermassive black holes at the cores of galaxies.

These are the first confirmed observations of stars forming in this kind of extreme environment. The discovery has many consequences for understanding galaxy properties and evolution. The results are published in the journal Nature.

A UK-led group of European astronomers used the MUSE and X-shooter instruments on the Very Large Telescope (VLT) at ESO’s Paranal Observatory in Chile to study an ongoing collision between two galaxies, known collectively as IRAS F23128-5919, that lie around 600 million light-years from Earth. The group observed the colossal winds of material — or outflows — that originate near the supermassive black hole at the heart of the pair’s southern galaxy, and have found the first clear evidence that stars are being born within them.

Such galactic outflows are driven by the huge energy output from the active and turbulent centres of galaxies. Supermassive black holes lurk in the cores of most galaxies, and when they gobble up matter they also heat the surrounding gas and expel it from the host galaxy in powerful, dense winds.