Tuesday, 23 January, 2018

Supermassive black gap 'double burps' - then naps

Black holes Supermassive Black Hole is Caught Letting Out Massive 'Burps'
Theresa Hayes | 14 January, 2018, 13:55

While even light can not escape the pull of one of these gravity wells, blacks holes do, very occasionally, "burp" back out chunks of half-consumed gas.

"Black holes are voracious eaters, but it turns out they don't have very good table manners", Julie Comerford, from the University of Colorado, Boulder, told the 231st American Astronomical Society meeting in Washington DC.

Supermassive black holes are the largest form of the space giant and are typically found in the centre of big galaxies.

A paper on the subject was published in a recent issue of The Astrophysical Journal and is available online. The discovery is evidence that black holes can switch their power outputs on and off more repeatedly. "Fortunately, we happened to observe this galaxy at a time when we could clearly see evidence for both events".

Scientists have already spotted black holes burping before, although this time they observed one black hole do it multiple times. For comparison, one light-year is roughly six trillion miles. The Apache Point facility is owned by the Astrophysical Research Consortium, a group of 10 USA research institutions that includes CU Boulder.

The researchers think the black hole erupted twice because it consumed two separate meals.

Ms Comerford stated: "There's a stream of stars and gas connecting these two galaxies".

A super-massive black hole 800 million light-years away just gave evidence of a cyclical feeding cycle, possibly confirming theories about the life cycles of these mysterious celestial objects.

"These are the kinds of bubbles we see after a black hole feeding event", she said.

Meanwhile, another burp must have taken place much more recently, having had less time to fan our across the stars.

This is an image of galaxy SDSS J1354 1327 (lower center) and its companion galaxy SDSS J1354 1328 (upper right). The X-ray spectrum shows the supermassive black hole lies within a heavy veil of dust and gas, said Comerford.

"This galaxy really caught us off guard", said study author and University of Colorado Boulder doctoral student Rebecca Nevin. "We were able to show that the gas from the northern part of the galaxy was consistent with an advancing edge of a shock wave, and the gas from the south was consistent with an older outflow from the black hole".

Our own galaxy, the Milky Way, has experienced at least one burp, Ms Comerford added - noting how "Fermi bubbles" had been detected shining at the extreme end of the electromagnetic spectrum. In 2010, another research team discovered a Milky Way belch using observations from the orbiting Fermi Gamma-ray Observatory to look at the galaxy edge on.

This energy is released in quasars that are seen visible light and X-ray wavelengths.

The observations are important because they support previous theories - not demonstrated until now - that black holes should go through these cycles.