Connect with us

Space

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.

Read More On This At ScienceAlert – Latest

Comments

Space

“Decision not made”: Head of NASA admitted that the US may not be able to land at the moon’s pole

The head of NASA is unsure about the ability of the United States to land at the Moon’s South Pole. The director of the agency admitted this to the scientists, admitting that instead of the pole, the astronauts can fly to the places of the previous Apollo landings.

NASA Director Jim Bridenstine made an unexpected statement, talking about plans for the first landing of American astronauts on the moon in 50 years. As you know, during the Artemis 3 mission, in accordance with the plans of President Donald Trump, the United States plans to carry out a manned launch to the Moon in 2024 and, for the first time since 1972, land astronauts on it in the region of the Moon’s South Pole.

During this mission, a week-long landing of “the first woman and another man” is planned on the surface of the Earth’s satellite.

Until recently, the fact that the landing is planned precisely in the polar region was not questioned – this is the most unexplored region of the Moon, scientists assume there are water deposits, and it is there that the Russian automatic station “Luna-25” will be launched in 2021.

However, the day before, speaking at an online conference of the Lunar Exploration Analysis Group, the head of NASA admitted that the flight to the South Pole would not take place. Answering the question whether it is possible in the future for astronauts to fly to the sites of past Apollo missions, the official not only answered in the affirmative, but also made it clear that this option is being considered for 2024.

“For the first Artemis 3 mission, our goal is to reach the South Pole, and of course, this is the most interesting place right now, because there is water ice, we need to study it, understand how to get it and use it,” Bridenstine said. “But I can imagine that these places (of the Apollo landings) can be interesting too.

If we decide that the South Pole is out of reach for Artemis-3, then perhaps we will learn more by going to where we left our instruments in the past … There may be scientific discoveries, and, of course, the very inspiration from the return to the Apollo landing sites will be amazing. However, these decisions have not yet been made”.

In doing so, the official added, the United States needs to develop “codes of conduct” to protect these historic sites from subsequent expeditions.

The Moon’s South Pole was designated the target of the first American astronaut landing in many years in 2019 in a speech by US Vice President Mike Pence at the National Space Council. “To reach the moon in the next five years, we must choose our goals now. NASA already knows that the South Pole is of great scientific, economic and strategic value, and now is the time to decide to go there,” the official said.

Now Bridenstein’s statement says that NASA may abandon its previous plans. Landing near the poles of the Moon is technically more difficult than in the equatorial or mid-latitudes, and neither automatic nor manned missions have landed near the poles before.

And although Bridenstein’s statement about the possible refusal to fly to the Pole is still vague, it has already worried the scientists attending the conference: at subsequent sessions they began to seek clarifications from NASA representatives.

This is due to the fact that the scientific tasks that must be set before scientists depend on the selected region. Just recently, NASA asked specialists to participate in the development of scientific problems that American astronauts could solve during the first landing on the moon in several decades.

“At this point, we are instructed to do our job with a polar landing in mind,” said Renee Weber of the Marshall Space Center when asked about a possible relocation of the landing site. According to representatives of NASA, the department has just begun to select certain areas. “The scientific community will be involved in this process,” said Jake Bleacher, head of one of the NASA divisions.

And while NASA continues to hope for a long-term base camp on the moon, agency officials have made it clear that it is not yet known whether a second manned mission, Artemis 4, will follow in the footsteps of the first. “We really need to assess the ability of our landers and what areas they can go to,” Bleacher said, adding that “it’s not clear” about how long after the first mission the second will go.

In the spring, it became known that Boeing had lost the competition for the design of lander, and Blue Origin, SpaceX and Dynetics were among the winners. Three winners of the competition were announced in April, under the initial contract SpaceX will receive $ 135 million, Blue Origin – $ 579 million, Dynetics – $ 253 million.

Continue Reading

Space

An amateur astronomer from Brazil discovered a large near-Earth asteroid

Brazilian amateur astronomer Leonardo Amaral discovered a large asteroid 2020 QU6 with a diameter of about 700 meters. He approached the Earth on Thursday and flew 40 million kilometers from its surface, the Planetary Society writes.

“This event was another reminder of what we have discovered, not all large near-Earth asteroids, we must continue to support the ground-based astronomy and invest in space projects, like the telescope NEOSM from cosmic threats to the full protection of the Earth.” – said  a leading adviser on space Casey Dreyer Planetary Society Policy.

Asteroid 2020 QU6, which Leonardo Amaral discovered at the end of August this year, has become one of the largest near-Earth asteroids in recent years. At the same time, he was not potentially dangerous for humanity and life on Earth, since in the foreseeable future he would not approach it at a dangerous distance.

It makes a revolution around the Sun in about 3.2 years, moving away from it twice as far as the Earth’s orbit is located. 2020 QU6 crosses the orbit of Mars and reaches the inner boundary of the main asteroid belt. At the maximum point of approach to the Sun, the asteroid almost reaches the Earth’s orbit, approaching the star by 1.1 astronomical units (the average distance between the star and our planet).

In the past few decades, scientists around the world have been actively monitoring near-Earth asteroids and conducting a kind of space “census” among them, trying to understand how dangerous they are for humanity. Now astronomers know about 22 thousand asteroids, which periodically approach the Earth at a relatively short distance.

Almost two thousand of them are included in the PHA (Potentially hazardous asteroids) catalog – a list of small celestial bodies that are potentially dangerous to life on Earth. To get on this list, an asteroid must approach our planet at a distance of no more than 8 million km, and also be large enough so as not to collapse when passing through the atmosphere and cause a regional catastrophe.

Continue Reading

Space

Australian astronomers were scanning alien FM radio broadcasts for 17 hours

Terrestrial receiving antennas were directed towards the constellation Vela.

Australian astronomers from the International Center for Radio Astronomy Research (ICRAR) at Curtin University caught FM radio transmissions from aliens for 17 hours in a row, aiming the antennas of their new Murchison Widefield Array (MWA) radio telescope at Vela – a constellation of the southern firmament. 

We searched and searched, but we never caught anything, as reported in the specialized journal Publications of the Astronomical Society of Australia, referred to by the ScienceAlert portal. 

They say, they did not find a single meaningful or even ordered low-frequency signal – from technosignatures, scientifically opposing, which could belong to representatives of some extraterrestrial civilization.

Antenna field of the Australian radio telescope.  Photo: www.mwatelescope.org

Antenna field of the Australian radio telescope. Photo: www.mwatelescope.org

The “radio listeners” – Chenoa Tremblay and Steven Tingay – for some reason we decided that if they exist by reason, they should broadcast at low frequencies. Therefore, we used the MWA radio telescope operating in the 72-240 MHz range. In total, astronomers surveyed an area containing approximately 10 million stars. But nothing. Deaf. 

Technosignatures were not revealed, and 75 exoplanets already discovered in that direction. Either the aliens are not there at all, or they are very far away – so much so that their “broadcasting” has not yet reached us, or their radio transmitters are very weak and the signals propagated by them merge with the general background.

Researchers are not discouraged. On the contrary, they were inspired. Since we were convinced that it is possible to search for signals of extraterrestrial intelligence, as they say, in passing – simultaneously solving more serious scientific problems.

A more sensitive low-frequency radio telescope, the Square Kilometer Array (SKA), will soon be erected in western Australia, which will be able to listen to billions of star systems. Not a single alien radio will hidden from it.

By the way, radio transmissions from Earth are now being heard in a sphere just over 200 light-years across. Such a distance has spread the electromagnetic waves that humanity has been emitting into the surrounding space since the invention of radio.  These waves, moving at the speed of light, “washed” more than 6 thousand star systems. 

They may already know about us there. And in the worlds located beyond the sphere, which astronomers call the “bubble of humanity”, the existence of intelligent humanity is not even suspected. But over time, they will be revealed to us, as we do to them.

Drake's equation began to give positive results.  Photo: NASA exoplanet research program.

Drake’s equation began to give positive results. Photo: NASA exoplanet research program.

No, there is someone

If you believe the American astronomers Louis Anchordoqui, Susanna Weber and Jorge Soriano, then in the foreseeable space there is someone to broadcast. In their opinion, within 10 kiloparsecs – this is about 30 thousand light years – there is at least one developed civilization that possesses the technology that allows the propagation of radio signals.

The astronomers presented their arguments in a work called ” Is there anybody out there? “

Anchordoqui and his colleagues came to the conclusion about the existence of alien civilizations by analyzing the famous Drake equation, which allows calculating the probable number of extraterrestrial civilizations. This equation was compiled in 1960 by the professor of astronomy and astrophysics at the University of California, Frank Donald Drake.

In the equation named after the scientist, there are seven members: the number of stars formed per year, the proportion of stars with planets, the number of planets or their satellites with conditions suitable for life, the probability of the birth of any life, the probability of its transformation into a reasonable one, the proportion of planets with highly developed creatures, the lifetime of a civilization that lives on the planet.

Calculations using the Drake equation, carried out many times already, gave a different number of alien life: from zero to 5 thousand. Such a wide spread arose from the fact that scientists differently estimated the values ​​of the parameters included in the equation. They were based, of course, on the ideas and observations of their time.

Now, as it turned out, there are much more stars in the Universe than it seemed before, and there are so many planets, including those that seem to be livable.

New calculations have led to an encouraging result: the number of civilizations in the foreseeable space is greater than zero.

The bubble of humanity is roughly 200 light-years in diameter.  Photo: wikipedia.org

The bubble of humanity is roughly 200 light-years in diameter. Photo: wikipedia.org

Our galaxy alone may contain 6 billion Earth-like planets

Canadian astronomers from the University of British Columbia (UBC) are also encouraging. In an article published in The Astronomical Journal, they prove that planets similar to ours – a kind of Second Earths – are by no means uncommon in the Milky Way, containing a myriad of stars – more than 400 billion. 

Our Earth is not alone.  Photo: wikipedia.orgOur Earth is not alone. Photo: wikipedia.org

Continue Reading
Advertisement

DO NOT MISS

Trending