Did you know supermassive black holes shoot UFOs out into space? Not the UFOs you are thinking about, but ultra-fast outflows.
Hot ionized gas streams out of the accretion disk of supermassive black holes and slams into their surroundings at speeds up to 40% of the speed of light. And this kind of ultra-fast outflow (UFO) might explain the nearly empty darkness that surrounds the center of many galaxies.
Most big galaxies contain a central black hole millions of times more massive than the Sun. But galaxies hosting more massive black holes also possess bulges that contain, on average, faster-moving stars.
This link suggested some sort of feedback mechanism between a galaxy’s black hole and its star-formation processes.
In 2019, astronomers observed galaxy PG 1114+445 using the European Space Agency’s X-ray Multi-Mirror Mission (XMM-Newton) telescope. For the first time, they snapped an image of UFOs pushing other material around at the heart of a galaxy.
The study found these black hole winds impact the galaxy on a larger scale, possibly providing the missing link.
The gigantic outflows have a huge effect on the ‘interstellar’ matter surrounding holes and ‘sweeps it away like a snowplow’. This matter can be involved in the formation of stars.
You Might Like This: The Supermassive Black Hole That Burps
These observations suggest the bigger the supermassive black hole, the faster the inner stars in its host galaxy move.
Gravity alone can’t explain this relationship. But if the larger black holes spew more intense outflows that shove out gas at higher speeds, they could also be sweeping away nearby stars and accelerating them to higher speeds.
Scientists already knew about UFO blasts. However, this discovery relates a different type of outflow that has the speed of a UFO but the properties of a slower outburst called a ‘warm absorber’.
To measure the temperatures of these winds, scientists studied X-rays coming from the edge of the black hole. As they travel towards Earth, these X-rays pass through the outflows. Elements such as iron or magnesium present in the outflows can absorb specific parts of the X-ray spectrum. Thus, creating signature “dips” in the X-ray signal.
By observing these dips, called absorption features, astronomers can learn what elements exist in the wind.
Astronomers have spotted six of these outbursts of wind before. Studying them brings us closer to understanding how they affect the formation of stars and galaxies.
These forces push around the interstellar matter like wind pushing boats in the sea, cleaning away gas, and stopping it from gathering around the black holes.
Active black holes acquire their power by gradually accreting – or “feeding” on – million-degree gas stored in a vast surrounding disk.
Near the inner edge of the disk, a fraction of the matter orbiting a black hole often is redirected into an outward particle jet.
ESA said supermassive black holes transfer their energy into the surrounding environment through these outflows and gradually clear the central regions of the galaxy from gas, which could then halt star formation.
When galaxies are young, they have a lot of available gas to form stars, which are birthed when the gas cools, contracts, and ultimately collapses into stars.
But winds can stop star formation by either heating the gas so it can’t cool and collapse, or by simply pushing the gas out of the galaxy entirely, removing the raw materials from which stars are born.
Galaxies today produce stars far less frequently than they used to in the early stages of their evolution. Compared to the average galaxy today, which produces stars at rates equaling about 10 times the mass of our sun per year, the rate of star formation in those same galaxies appears to have been up to 10 times higher when they were younger. Our galaxy, The Milky Way produces stars weighing about 3 solar masses (equivalent to 3 Suns) per year. And, stars equivalent to 1 solar mass die every year.
Bottom line is that these winds may have a strong influence on regulating the growth of the host galaxy by clearing the surrounding gas away and suppressing star formation.