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Researchers Now Say That Black Holes May Form without Collapsing Stars

Source: Interesting Engineering

Supermassive Black Holes (SMBHs) have, until now, traditionally been believed to only form after
the explosion or collapse of a star.

The gravitational force of a star collapsing in on itself at the end of its lifespan — after a hypernova explosion — creates a black hole.

These, in theory, become Supermassive Black Holes by sucking in surrounding matter until they grow to an enormous size.

There is one big problem with this theory, but new research by researchers at Western University in Ontario, Canada, may provide us with an answer.

The problem

The outward pressure of a star’s nuclear fusion is what prevents it from collapsing under the gravitational force created by its own mass. When the energy dissipates, the star collapses in on
itself. Then, a black hole forms and becomes larger by ‘feeding’ on its surroundings.

This takes a very long time — Supermassive Black Holes form over the course of millennia.

The problem is that scientists have observed SMBHs that are too old to have had enough time after the Big Bang, and gradually form into the space giants that they became.

For example, one SMBH was discovered by astronomers in 2017 that was much too large, especially to have been so large 690 million years after the Big Bang.

New research findings

Two researchers at Western University in Ontario, Canada, believe they might have an answer. Their new theory, called ‘direct collapse,’ attempts to provide an explanation for these ancient SMBHs.

The authors are Shantanu Basu and Arpan Das. Basu writes that SMBHs were able to form very quickly in the early universe before the growth was halted by the radiation of forming stars.

In direct-collapse black holes, Universe Today reports, the Eddington Limit regulates mass growth. Ancient black holes could exceed that limit slightly, the researchers say. They call this ‘super-Eddington accretion.’

“Supermassive black holes only had a short time period where they were able to grow fast and then at some point, because of all the radiation in the universe created by other black holes and stars, their production came to a halt,” Basu explained in a press release published on Eurekalert.org.

“That’s the direct-collapse scenario.”

“This is indirect observational evidence that black holes originate from direct-collapses and not from stellar remnants,” Basu continued, putting a spanner in the works for a long-held belief in the
scientific community on the formation of black holes.

Their findings are published in a paper, called ‘The Mass Function of Supermassive Black Holes in the Direct-collapse Scenario,’ found in The Astrophysical Journal Letters.

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Space

A giant explosion recorded on the star Betelgeuse

Betelgeuse is considered a doomed star, and its explosion is only a matter of time. Observations from NASA’s Hubble Space Telescope show that the sudden darkening of the supergiant star Betelgeuse was most likely caused by the enormous amount of hot matter ejected into space, forming a dust cloud that blocked the starlight emanating from Betelgeuse’s surface.

The researchers speculate that the dust cloud was formed when superhot plasma released from the upward flow of a large convection cell on the star’s surface passed through the hot atmosphere into the colder outer layers, where it cooled down and formed dust particles. The resulting dust cloud has blocked light from about a quarter of the star’s surface since late 2019. By April 2020, the star has returned to normal brightness.

Betelgeuse is an aging red supergiant star that has grown in size due to complex evolutionary changes in its fusion furnace at its core. The star is now so huge that if it replaced the Sun at the center of our solar system, its outer surface would extend beyond Jupiter’s orbit.

Betelgeuse’s unprecedented strong blackout phenomenon, visible even to the naked eye, began in October 2019. By mid-February 2020, the monster star has lost more than two-thirds of its brilliance.

This sudden blackout has puzzled astronomers, who have tried to develop several theories of abrupt change. 

Hubble recorded traces of dense, heated matter moving through the star’s atmosphere in September, October, and November 2019. Then, in December, several ground-based telescopes observed a decrease in the star’s brightness in the southern hemisphere.

“With the Hubble Telescope, we see material leaving the visible surface of the star and moving through the atmosphere before the dust was formed, which made the star appear dim,” said Dupree. “We could see the effect of a dense hot region moving in the southeastern part of the star.

“This material was two to four times brighter than the normal brightness of the star. And then, about a month later, the southern part of Betelgeuse became noticeably dimmer as the star became fainter. We think that it is possible that the dark cloud came from an explosion discovered by Hubble “.

The article was published August 13 in the Astrophysical Journal.

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Space

Massive sunspot facing Earth could be bad news as we enter a new 25 solar cycle

A massive sunspot has formed on the Sun, which will be turned towards our planet, which can lead to large and very strong flares aimed at the Earth

The sunspot AR2770, which was recorded earlier this week, will increase in size. This particular sunspot has already emitted several minor flares, which have caused nothing serious, except for “small waves of ionization running through the upper atmosphere of the Earth.”

However, this sunspot, which can be up to 50,000 kilometers in diameter, can release enormous amounts of energy, which in turn can lead to solar flares. 

This phenomenon is called coronal mass ejections (CMEs). These outbreaks can have a serious impact on radio communications, global positioning systems (GPS) communications, power grids and satellites.

According to the National Oceanic and Atmospheric Administration (NOAA), CMEs can “oscillate electrical currents in space and excite electrons and protons trapped in Earth’s changing magnetic field.” Solar flares caused by these CMEs can also cause intense light in the sky called auroras.

On the Sun, the active zone was transformed into an ideal number 2


What is a sunspot?

A spot is a dark area in the sun that appears dark on the surface and is relatively cooler than other parts. These sunspots contain electrically charged gases that create areas of powerful magnetic forces. Gases on our Sun are constantly moving, which causes irregularities in this “magnetic field”. This activity is also called “solar activity”. The levels of solar activity do not remain the same and differ from one solar cycle to the next.

What is a solar flare?

Solar flares are the result of changes in the magnetic fields at sunspots that cause a huge explosion. These solar flares are often thrown into space. The energy of the explosion of solar flares can be equivalent to a trillion atomic bombs dropped on Hiroshima and Nagasaki in 1945.

Is a new 25 cycle starting?

At the moment, there is no complete confidence in the beginning of the 25th solar cycle, which will mark a gradual increase in solar activity. Only one thing is clear – the solar minimum, if suddenly it continues, nothing good for our planet and, accordingly, will not bring us all.

Due to the practically zero activity of the Sun on Earth, record levels of cosmic radiation are recorded. To put it simply, our entire planet is essentially turned into a huge microwave.

But the resumption of solar activity after a long period of calm is also not good, since no one can predict the levels of this activity, and if it is high, this could potentially lead to a powerful super-flash that will cover the Earth.

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What did Mars look like millions of years ago? New theory

At the moment, Mars is considered the most suitable planet for human life. It is in many ways similar to our native Earth: the surface is solid, the day lasts almost the same 24 hours and periodically there is a change of seasons. 

Scientists are sure that millions of years ago between our planet and Mars there were even more similarities, such as the presence of water and living organisms. He has one snag – in time immemorial the sun was much weaker than it is now, and Mars was quite far from it and was not going to approach. It turns out that the planet was cold and there could not be rivers and oceans on it. 

But how, then, can explain the presence of valleys and depressions on its surface, which were clearly formed as a result of the flow of water? Canadian scientists have started looking for an explanation for this mysterious phenomenon. 

In the course of scientific work, they managed to put forward a theory that greatly changes the idea of ​​scientists about the past of the Red Planet. Perhaps Mars looked like a giant snowball.

Millions of years ago, Mars was hardly a warm place

Water on Mars

The essence of the theory was published in the scientific journal Nature Geoscience . According to one of the study’s authors, Anna Grau Galofre , over the past 40 years, the scientific community has believed that irregularities on the surface of Mars were formed by the movement of rivers. 

However, there are distinctive features between valleys and depressions in different regions of the planet. To find out what factors could affect the structure of the irregularities, scientists decided to find a place on Earth, the surface of which is as close as possible to the Martian landscape. However, researchers have long known about the existence of such a place.

Mars on Earth

One of the most Mars-like places on our planet is considered the uninhabited island of Devon, located in northern Canada. Almost all of its surface is a cold and dry desert. If you look at the island from a bird’s eye view or even from a satellite, you will notice that its surface is really very similar to the vastness of the Red Planet. 

It is also full of all kinds of irregularities and scientists are well aware of how they were formed. Since Devon Island is a rather cold place, most of the rivers there flow under a layer of ice. Part of the ice sheet melted over time and the valleys left by the rivers are now clearly visible to us. In their structure, they are very different from the valleys formed by rivers that flow in the open.

The surface of Devon Island is very similar to the Martian landscape

So, scientists became aware of the distinctive features of the two types of valleys. Based on this data, they developed an algorithm that was able to quickly study photographs of 10,000 Martian irregularities. 

Among them, the researchers found many valleys, which clearly formed under a thick layer of ice. Most of them were formed about 3.8 billion years ago. It turns out that once upon a time, although not all, but most of Mars, was covered with ice and snow. But scientists assumed that it was very similar to our blue-green Earth.

Above is the surface of Mars, and below is the surface of Devon Island

Life on Mars

If Mars really was covered with layers of ice, then the probability of the existence of living organisms on it increases markedly. The fact is that microorganisms could well inhabit the waters hidden under the ice sheet. And this shield, in turn, could perfectly protect them from cosmic radiation. 

Indeed, the Red Planet has a very weak magnetic field, which is precisely what serves to protect against harmful radiation. So, despite the changes in the idea of ​​the appearance and conditions of ancient Mars, the probability that at least primitive creatures lived on it remained. Maybe someday their traces will be discovered by devices like InSight and we will gain confidence that life on other planets can exist.

According to the new theory, 3.8 billion years ago Mars looked something like this

The computer algorithm created within the framework of scientific work will not disappear. According to the developers, it can be useful for studying the past of the Earth. 

Technologies existing at the moment allow us to look at history no further than 5 million years, and a new algorithm can reconstruct the history of glaciations on our planet over the past 35 million years. It sounds intriguing, so we can only hope that new discoveries will not be long in coming.

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