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For The First Time Ever, Astronomers Have Observed a Black Hole Ejecting Matter Twice

Black holes don’t just sit there munching away constantly on the space around them. Eventually they run out of nearby matter and go quiet, lying in wait until a stray bit of gas passes by.

Then a black hole devours again, belching out a giant jet of particles. And now scientists have captured one doing so not once, but twice – the first time this has been observed.

The two burps, occurring within the span of 100,000 years, confirm that supermassive black holes go through cycles of hibernation and activity.

It’s actually not as animalistic as all that, since black holes aren’t living or sentient, but it’s a decent-enough metaphor for the way black holes devour material, drawing it in with their tremendous gravity.

But even though we’re used to thinking how nothing ever comes back out of a black hole, the curious thing is that they don’t retain everything they capture.

When they consume matter such as gas or stars, they also generate a powerful outflow of high-energy particles from close to the event horizon, but not beyond the point of no return.

“Black holes are voracious eaters, but it also turns out they don’t have very good table manners,” said lead researcher Julie Comerford, an astronomer at the University of Colorado Boulder.

“We know a lot of examples of black holes with single burps emanating out, but we discovered a galaxy with a supermassive black hole that has not one but two burps.”

The black hole in question is the supermassive beast at the centre of a galaxy called SDSS J1354+1327 or just J1354 for short. It’s about 800 million light-years from Earth, and it showed up in Chandra data as a very bright point of X-ray emission – bright enough to be millions or even billions of times more massive than our Sun.

The team of researchers compared X-ray data from the Chandra X-ray observatory to visible-light images from the Hubble Space Telescope, and found that the black hole is surrounded by a thick cloud of dust and gas.

“We are seeing this object feast, burp, and nap, and then feast and burp once again, which theory had predicted,” Comerford said. “Fortunately, we happened to observe this galaxy at a time when we could clearly see evidence for both events.”

That evidence consists of two bubbles in the gas – one above and one below the black hole, expulsions particles following a meal. And they were able to gauge that the two bubbles had occurred at different times.

The southern bubble had expanded 30,000 light-years from the galactic centre, while the northern bubble had expanded just 3,000 light-years from the galactic centre. These are known as Fermi bubbles, and they are usually seen after a black hole feeding event.

From the movement speed of these bubbles, the team was able to work out they occurred roughly 100,000 years apart.

So what’s the black hole eating that’s giving it such epic indigestion? Another galaxy. A companion galaxy is connected to J1354 by streams of stars and gas, due to a collision between the two. It is clumps of material from this second galaxy that swirled towards the black hole and got eaten up.

“This galaxy really caught us off guard,” said 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.”

The Milky Way also has Fermi bubbles following a feeding event by Sagittarius A*, the black hole in its centre. And, just as J1354’s black hole fed, slept, then fed again, astronomers believe Sagittarius A* will wake to feed again too.

The research was presented at the 231st meeting of the American Astronomical Society, and has also been published in The Astrophysical Journal.

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Unusual signals come from the GJ 1151 system

Most likely, radio emission is created by the interaction of a planet the size of the Earth with the strong magnetic fields of its star.

Using the LOFAR low-frequency radio telescope, astronomers recorded unusual radio emission coming from the red dwarf GJ 1151, which is located at a distance of about 28 light-years from Earth, these signals, according to scientists, contain evidence of the auroras created by the interaction of the planet with the strongest magnetic fields of the star. The results of the study are presented in the journal Nature Astronomy.

“Radio emission from the interaction of a star and a planet was predicted more than thirty years ago, but only now we were able to identify its signature in the data. Success achieved paves the way for a new way to detect exoplanets in the habitable zone and study their surroundings, ”the authors of the study say.

Red dwarfs are the most common type of star in the Milky Way. They are much smaller and colder than the Sun and have extremely strong magnetic fields. This means that any potentially inhabited planet in the system of such a star, due to its proximity to it, is subjected to intense magnetic activity, which can heat it and even destroy the atmosphere. The radio emission associated with this process is one of the few tools available to evaluate this effect.

“The movement of the planet through the strong magnetic field of the red dwarf acts like an electric motor. This process generates a huge current that provokes radiance and creates radio emission, ”explained Harish Vedantam, lead author of the study from the Netherlands Institute of Radio Astronomy.

In the solar system, similar currents are not generated due to the weak magnetic field of the sun and the large distance to the planets. However, the interaction of the Io satellite with the magnetic field of Jupiter also creates a fairly bright radio emission, at low frequencies superior to the sun.

“We adapted our knowledge from decades of radio observations of Jupiter to the data on the star GJ 1151. For many years it was predicted that the Jupiter-Io system should exist in a larger version of the star-planet, and the radiation recorded by us from GJ 1151 is very well consistent with theory. Today we know that almost every red dwarf contains terrestrial planets, so there must be other stars showing such radiation,” Joe Cullingham added, the co-author of a study from the Netherlands Institute of Radio Astronomy.

Astronomers note that the sensitivity of modern instruments should allow them to find about a hundred more of such systems in the solar vicinity, and, more importantly, assess the conditions in which exoplanets reside in them.

“The main goal is to determine what effect the magnetic activity of a star has on the habitability of an exoplanet, and radio emission is the most important link in this puzzle,” Harish Vedantam concluded.

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Mankind may face deadly viruses in search of new life in space

Professor Dov Greenbaum hypothesized that humanity’s search for signs of life outside the Earth could lead to an even greater threat of infection than a new kind of coronavirus.

In his material, the scientist notes that in the era of human mobility, new viruses spread very quickly, while bacteria grown in outer space can become even more deadly.

For a more detailed study of this issue, samples of genetically engineered bacteria samples are sent aboard the ISS. Despite the fact that the spread of extraterrestrial viruses in real life is considered a very unlikely scenario, the scientist warns against excessive optimism. The astrobiologist claims that dangerous viruses and infections can live in space on rocks that seem dead to the surface. In connection with these, Greenbaum believes that in the case of the reality of the existence of extraterrestrial life forms, their search without appropriate precautions “can lead to infections that will be even more dangerous and deadly than the acclaimed coronavirus.”

The professor also recalled that life was found in those places that were previously considered impossible for the existence of living organisms. So, NASA is going to deliver stones from the surface of Mars, and the Japanese space mission is already returning from the asteroid Ryugu with samples of its rock. At the end of this year, the Japanese Hayabusa2 will reach Earth. According to Greenbaum, it is likely that one of these missions will deliver a fundamentally new type of space infections to Earth.

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Unknown carbon form found in Chelyabinsk meteorite

Scientists have discovered an unknown form of carbon on Earth in fragments of a meteorite that fell in the Chelyabinsk region in 2013, said Sergei Zamozdra, assistant professor of theoretical physics at the Chelyabinsk State University.

He said that the dean of the Faculty of Physics Sergey Taskaev (now the rector of the university. – Ed.), while studying samples of meteorite dust, noticed something amazing.

“At first he thought it was a diamond, because there were six faces. Later in Germany, this crystal was pulled out using micro-tweezers and when X-rayed – it turned out to be not a diamond, but a carbon crystal. We measured the position of atoms, the planes of interatomic, then Korean specialists on a computer calculated that, indeed, such an arrangement of atoms is possible, “he explained.

According to the scientist, carbon can have many modifications. However, such carbon has not yet been found on Earth, and experts will have to figure out how it came about, calculating different options.

“One option is that it arose in space conditions, because we are talking about a process of billions of years. Another is directly during a flight in the Earth’s atmosphere,” the scientist believes.

According to the press service of Chelyabinsk State University, the study of meteorite fragments was carried out by Sergey Taskaev together with colleagues from the Technical University of Darmstadt (Germany) and the National University of Kengpuk (Republic of Korea).

In the Chelyabinsk region on February 15, 2013, thousands of people watched a very bright object in the sky. In the first minutes, the expansion and twisting of its smoky plume was visible, followed by an air wave strike, similar to the sound of a strong explosion.

Fragments of the meteorite were found in the vicinity of Chebarkul, but the largest – more than 600 kilograms – was raised from the lake of the same name. Now it is stored in Chelyabinsk in the South Ural State Historical Museum under a special dome in the exhibition hall, where everyone can see it.

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