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How were Supermassive Black Holes Already Forming and Releasing Powerful Jets Shortly After the Big Bang? – Universe Today

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In the past few decades, astronomers have been able to look farther into the Universe (and also back in time), almost to the very beginnings of the Universe. In so doing, they’ve learned a great deal about some of the earliest galaxies in the Universe and their subsequent evolution. However, there are still some things that are still off-limits, like when galaxies with supermassive black holes (SMBHs) and massive jets first appeared.

According to recent studies from the International School for Advanced Studies (SISSA) and a team of astronomers from Japan and Taiwan provide new insight on how supermassive black holes began forming just 800 million years after the Big Bang, and relativistic jets less than 2 billion years after. These results are part of a growing case that shows how massive objects in our Universe formed sooner than we thought.

Astronomers have known about SMBHs for over half a century. In time, they came to realize that most massive galaxies (including the Milky Way) have them at their cores. The role they play in the evolution of galaxies has also been the subject of study, with modern astronomers concluding that they are directly related to the rate of star formation in galaxies.

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Similarly, astronomers have found that SMBHs have tight accretion disks around them where gas and dust are accelerated to close to the speed of light. This causes the center of some galaxies to become so bright – what are known as active galactic nuclei (AGNs) – that they outshine the stars in their disks. In some cases, these accretion disks also lead to jets of hot material that can be seen from billions of light-years away.

According to conventional models, galaxies didn’t have enough time to develop central black holes when the Universe was less than a billion years old (ca. 13 billion years ago). However, recent observations have shown that black holes were already forming at the center of galaxies at the time. Addressing this, a team of scientists from SISSA proposed a new model that offers a possible explanation.

For their study, which was led by Lumen Boco – a Ph.D. student from the Institute for Fundamental Physics of the Universe (IFPU) – the team started with the well-known fact that SMBHs grow in the central regions of early galaxies. These objects, the progenitors of elliptical galaxies today, had a very high concentration of gas and an extremely intense rate of new star formation.

The first generations of stars in these galaxies was short-lived and quickly evolved into black holes that were relatively small, but significant in number. The dense gas that surrounded them led to significant dynamic friction and caused them to migrate quickly to the center of the galaxy. This is where they merged to create the seeds of supermassive black holes – which slowly grew over time.

Artist’s impression of the path of the star S2 as it passes very close to the supermassive black hole at the center of the Milky Way. Credit: ESO/M. Kornmesser

As the research team explained in recent SISS press release:

“According to classical theories, a supermassive black hole grows at the centre of a galaxy capturing the surrounding matter, principally gas, “growing it” on itself and finally devouring it at a rhythm which is proportional to its mass. For this reason, during the initial phases of its development, when the mass of the black hole is small, the growth is very slow. To the extent that, according to the calculations, to reach the mass observed, billions of times that of the Sun, a very long time would be required, even greater than the age of the young Universe.”

However, the original mathematical model they developed showed that the formation process for central black holes could be very rapid in its initial phases. This not only offers an explanation for the existence of SMBH seeds in the early Universe but also reconciles the timing of their growth with the known age of the Universe.

In short, their study showed that the process of migration and mergers of early black holes can lead to the creation of an SMBH seed of 10,000 to 100,000 solar masses in just 50-100 million years. As the team explained:

“[T]he growth of the central black hole according to the aforementioned direct accretion of gas, envisaged by the standard theory, will become very fast, because the quantity of gas it will succeed in attracting and absorbing will become immense, and predominant on the process we propose. Nevertheless, precisely the fact of starting from such a big seed as envisaged by our mechanism speeds up the global growth of the supermassive black hole and allows its formation, also in the Young Universe. In short, in light of this theory, we can state that 800 million years after the Big Bang the supermassive black holes could already populate the Cosmos.”

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In addition to proposing a working model for observed SMBH seeds, the team also suggested a method for testing it. On the one hand, there are the gravitational waves that these mergers would cause, which could be identifiable using gravitational wave detectors like Advanced LIGO/Virgo and characterized by the future Einstein Telescope.

In addition, the subsequent development phases of SMBHs is something that could be investigated by missions like the ESA’s Laser Interferometer Space Antenna (LISA), which is expected to launch by around 2034. In a similar vein, another team of astronomers recently used the Atacama Large Millimeter/submillimeter Array (ALMA) to address another mystery about galaxies, which is why some have jets and others don’t.

These fast-moving streams of ionized matter, which travel at relativistic speeds (a fraction of the speed of light), have been observed emanating from the center of some galaxies. These jets have been linked to a galaxy’s rate of star formation because of the way they expel matter that would otherwise collapse to form new stars. In other words, these jets play a role in the evolution of galaxies, much like SMBHs.

For this reason, astronomers have sought to learn more about how black hole jets and gaseous clouds have interacted over time. Unfortunately, it has been difficult to observe these kinds of interactions during the early Universe. Using the Atacama Large Millimeter/submillimeter Array (ALMA), a team of astronomers managed to obtain the first resolved image of disturbed gaseous clouds coming from a very distant quasar.

Reconstructed images of MG J0414+0534, showing emissions from dust and ionized gas around a quasar (red) and carbon monoxide gas (green), which have a bipolar structure along the jets. Credit: ALMA (ESO/NAOJ/NRAO), K. T. Inoue et al.

The study that describes their findings, led by Prof. Kaiki Taro Inoue of Kindai University, recently appeared in the Astrophysical Journal Letters. As Inoue and his colleagues explained, the ALMA data revealed young bipolar jets emanating from MG J0414+0534, a quasar located roughly 11 billion light-years from Earth. These findings show that galaxies with SMBHs and jets existed when the Big Bang was less than 3 billion years old.

In addition to ALMA, the team relied on a technique known as gravitational lensing, where the gravity of an intervening galaxy magnifies light coming from a distant object. Thanks to this “cosmic telescope” and ALMA’s high resolution, the team was able to observe the disturbed gaseous clouds around MG J0414+0534 and determine that they were caused by young jets emanating from an SMBH at the center of the galaxy.

As Kouichiro Nakanishi, a project associate professor at the National Astronomical Observatory of Japan/SOKENDAI, explained in an ALMA press release:

“Combining this cosmic telescope and ALMA’s high-resolution observations, we obtained exceptionally sharp vision, that is 9,000 times better than human eyesight. With this extremely high resolution, we were able to obtain the distribution and motion of gaseous clouds around jets ejected from a supermassive black hole.”

These observations also showed that the gas was impacted where it followed the direction of the jets, causing particles to move violently and become accelerated to speeds of up to 600 km/s (370 mps). What’s more, these impacted gaseous clouds and the jets themselves were much smaller than the size of a typical galaxy at this age.

Artist’s impression of MG J0414+0534, showing the powerful jets that disturb the surrounding gas in the host galaxy. Credit: Kindai University

From this, the team concluded that they were witnessing a very early phase of jet evolution in the MG J0414+0534 galaxy. If true, these observations allowed the team to witness a key evolutionary process in galaxies during the early Universe. As Inoue summarized:

“MG J0414+0534 is an excellent example because of the youth of the jets. We found telltale evidence of significant interaction between jets and gaseous clouds even in the very early evolutionary phase of jets. I think that our discovery will pave the way for a better understanding of the evolutionary process of galaxies in the early Universe.”

Together, these studies demonstrate that two of the most powerful astronomical phenomena in the Universe emerged earlier than expected. This discovery also provides astronomers with the opportunity to explore how these phenomena evolved over time, and the role they played in the evolution of the Universe.

Further Reading: SISSA, ALMA, Astrophysical Journal, Astrophysical Journal Letters

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Take 2 for SpaceX's first astronaut launch with more storms – CTV News

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CAPE CANAVERAL, FLA. —
SpaceX pressed ahead with its second attempt to launch astronauts for NASA — a historic first for a private company — but more stormy weather threatened more delays.

Elon Musk’s company came within 17 minutes Wednesday of launching a pair of NASA astronauts for the first time in nearly a decade from the U.S., before the threat of lightning forced a delay.

NASA Administrator Jim Bridenstine said managers were debating whether to bump the next launch attempt from Saturday to Sunday to take advantage of a slightly improved forecast at Kennedy Space Center.

At an outdoor news conference Friday, Bridenstine stressed the need for safety for astronauts Doug Hurley and Bob Behnken — no matter how many times it takes to launch them in a SpaceX Dragon capsule atop a SpaceX Falcon 9 rocket to the International Space Station.

“We cannot forget this is a test flight. This — is — a — test — flight,” he repeated. “We will go when everything is as safe as we can possibly make it.”

Forecasters put the odds of acceptable weather conditions Saturday at 50-50, with the outlook improving to 60% favourable on Sunday. Rain and clouds were the main concerns for both days.

While NASA urged spectators to stay home because of the pandemic, prime viewing spots at area parks and beaches were packed Wednesday. A weekend launch could draw even bigger crowds. The Kennedy Space Center Visitor Complex reopened Thursday, after a 2 1/2-month shutdown, and within a few hours, all 4,000 tickets were snapped up for Saturday’s launch attempt.

President Donald Trump and Vice-President Mike Pence were expected to return for the Saturday attempt. The number of employees, journalists and guests inside remained extremely limited because of the pandemic.

Whether an attempt is made Saturday or Sunday, “There will be no pressure. We will launch when we’re ready,” Bridenstine said.

The last time astronauts launched to orbit from the U.S. was in 2011 when Atlantis closed out the 30-year space shuttle program. Hurley was on that mission as well.

NASA hired SpaceX and Boeing in 2014 to get the ball rolling again — kicking off a commercial revolution for getting people to low-Earth orbit, according to officials. In the meantime, NASA has spent billions of dollars to buy seats on Russian Soyuz capsules for U.S. astronauts, in order to keep the space station staffed.

Boeing’s first astronaut flight, on the company’s Starliner capsule, is not expected until next year.

Bridenstine offered high praise for Musk on Friday and all his personal touches: spiffy spacesuits, Tesla rides to the launch pad, a colour-co-ordinated rocket and capsule — and more.

Musk has brought “vision and inspiration” to the American space program, Bridenstine said. While there’s occasionally a little tension between NASA and SpaceX, “he gives me a commitment and he delivers on that commitment. That has happened every single time.”

——

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

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Proxima b, a confirmed — potentially habitable — Earth-sized planet, is a mere 4.2 light years away – The Post – Ontario

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At 1.17 Earth masses and in the habitable zone, scientists says it’s orbiting the nearest star to our sun

An artist’s depiction of what the surface of Proxima b might look like.

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A team of scientists from the University of Geneva has confirmed the existence of an Earth-sized planet orbiting the star closest to the sun. The planet, called Proxima b, is 1.17 times the mass of Earth and is located in the habitable zone of Promixa Centauri, 4.2 light years away.

Because Proxima Centauri is a red dwarf, much smaller and cooler than the sun, its habitable zone or Goldilocks zone — neither too hot nor too cold for liquid water to exist — is very close to the star. Proxima b orbits about 20 times closer to its star than Earth does to the sun, and a year on the planet is just over 11 Earth days long.

Red dwarf stars emit huge quantities of X-rays, and the scientists estimate the planet gets 400 times as much radiation as Earth. But Christophe Lovis, a researcher in the astronomy department of the university, was optimistic that this might not rule out the possibility of life, or at least habitability.

“Is there an atmosphere that protects the planet from these deadly rays?” he asks. “And if this atmosphere exists, does it contain the chemical elements that promote the development of life — oxygen, for example? How long have these favourable conditions existed?”

Proxima b could have a moon-sized neighbour.

Such questions will, he hopes, be answered in the next few years by the next generation of spectrometers, which will tease out data from the light of the star and its planet. The recent confirmation of Proxima b came from data from a spectrograph called ESPRESSO (Echelle Spectrograph for Rocky Exoplanet and Stable Spectroscopic Observations) mounted on the Very Large Telescope (yep, that’s its name) in Chile.

Proxima b was first detected by an earlier instrument called HARPS, or High Accuracy Radial Velocity Planet Searcher. “We were already very happy with the performance of HARPS, which has been responsible for discovering hundreds of exoplanets over the last 17 years”, says lead researcher Francesco Pepe. “We’re really pleased that ESPRESSO can produce even better measurements.”

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In addition, data from ESPRESSO included a second signal that could indicate yet another planet orbiting even closer to the star. “If the signal was planetary in origin, this potential other planet accompanying Proxima b would have a mass less than one third of the mass of the Earth. It would then be the smallest planet ever measured using the radial velocity method,” says Pepe. Proxima b could have a moon-sized neighbour.

Despite the relative nearness of Proxima Centauri as the sun’s closest stellar neighbour, we will have to rely on spectrographic data for the foreseeable future. Our fastest interplanetary probes, the Voyagers and New Horizons, would take tens of thousands of years to reach Proxima Centauri, even if they were headed in that direction. A plan called Breakthrough Starshot imagines a tiny probe travelling at 20 per cent of light speed, and making the journey in 20 years, but it’s still very much on the drawing board.

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Proxima b, a confirmed Earth-sized planet, is a mere 4.2 light year away Scientists confirm Earth-sized planet orbiting nearest star to our sun – National Post

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A team of scientists from the University of Geneva has confirmed the existence of an Earth-sized planet orbiting the star closest to the sun. The planet, called Proxima b, is 1.17 times the mass of Earth and is located in the habitable zone of Promixa Centauri, 4.2 light years away.

Because Proxima Centauri is a red dwarf, much smaller and cooler than the sun, its habitable zone or Goldilocks zone — neither too hot nor too cold for liquid water to exist — is very close to the star. Proxima b orbits about 20 times closer to its star than Earth does to the sun, and a year on the planet is just over 11 Earth days long.

Red dwarf stars emit huge quantities of X-rays, and the scientists estimate the planet gets 400 times as much radiation as Earth. But Christophe Lovis, a researcher in the astronomy department of the university, was optimistic that this might not rule out the possibility of life, or at least habitability.

“Is there an atmosphere that protects the planet from these deadly rays?” he asks. “And if this atmosphere exists, does it contain the chemical elements that promote the development of life — oxygen, for example? How long have these favourable conditions existed?”

Proxima b could have a moon-sized neighbour.

Such questions will, he hopes, be answered in the next few years by the next generation of spectrometers, which will tease out data from the light of the star and its planet. The recent confirmation of Proxima b came from data from a spectrograph called ESPRESSO (Echelle Spectrograph for Rocky Exoplanet and Stable Spectroscopic Observations) mounted on the Very Large Telescope (yep, that’s its name) in Chile.

Proxima b was first detected by an earlier instrument called HARPS, or High Accuracy Radial Velocity Planet Searcher. “We were already very happy with the performance of HARPS, which has been responsible for discovering hundreds of exoplanets over the last 17 years”, says lead researcher Francesco Pepe. “We’re really pleased that ESPRESSO can produce even better measurements.”

In addition, data from ESPRESSO included a second signal that could indicate yet another planet orbiting even closer to the star. “If the signal was planetary in origin, this potential other planet accompanying Proxima b would have a mass less than one third of the mass of the Earth. It would then be the smallest planet ever measured using the radial velocity method,” says Pepe. Proxima b could have a moon-sized neighbour.

Despite the relative nearness of Proxima Centauri as the sun’s closest stellar neighbour, we will have to rely on spectrographic data for the foreseeable future. Our fastest interplanetary probes, the Voyagers and New Horizons, would take tens of thousands of years to reach Proxima Centauri, even if they were headed in that direction. A plan called Breakthrough Starshot imagines a tiny probe travelling at 20 per cent of light speed, and making the journey in 20 years, but it’s still very much on the drawing board.

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