New Simulation Explains how Supermassive Black Holes Grew so Quickly

Supermassive Black Hole Survey. Credit: ESA/XMM-Newton/PSU/F. Zou et al./N.Trehnl/The TNG Collaboration

One of the main scientific objectives of next-generation observatories (like the James Webb Space Telescope) has been to observe the first galaxies in the Universe – those that existed at Cosmic Dawn. This period is when the first stars, galaxies, and black holes in our Universe formed, roughly 50 million to 1 billion years after the Big Bang. By examining how these galaxies formed and evolved during the earliest cosmological periods, astronomers will have a complete picture of how the Universe has changed with time.

As addressed in previous articles, the results of Webb‘s most distant observations have turned up a few surprises. In addition to revealing that galaxies formed rapidly in the early Universe, astronomers also noticed these galaxies had particularly massive supermassive black holes (SMBH) at their centers. This was particularly confounding since, according to conventional models, these galaxies and black holes didn’t have enough time to form. In a recent study, a team led by Penn State astronomers has developed a model that could explain how SMBHs grew so quickly in the early Universe.

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Echoes of Flares from the Milky Way’s Supermassive Black Hole

Michigan State University researcher Grace Sanger-Johnson found nine previously undiscovered flares from Sagittarius A*, the Milky Way’s central supermassive black hole, by sifting through a decade’s worth of X-ray data. Credit: NuSTAR/NASA
Michigan State University researcher Grace Sanger-Johnson found nine previously undiscovered flares from Sagittarius A*, the Milky Way’s central supermassive black hole, by sifting through a decade’s worth of X-ray data. Credit: NuSTAR/NASA

The supermassive black hole at the heart of our Milky Way Galaxy is a quiet monster. However, Sagittarius A* (or Sgr A* for short) is not totally dormant. Occasionally it gobbles down a blob of molecular gas or even a star and then suffers a bit of indigestion. That emits x-ray flares to surrounding space.

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Globular Clusters Should Contain More Intermediate-mass Black Holes

The M15 Globular Cluster (aka. Great Hercules Cluster). Astronomers suspect the existence of one or more intermediate-mass black holes at its heart. Credit: NASA/ESA/HST
The M15 Globular Cluster (aka. Great Hercules Cluster). Astronomers suspect the existence of one or more intermediate-mass black holes at its heart. Credit: NASA/ESA/HST

We live in a Universe studded with black holes. Countless stellar mass and supermassive ones exist in our galaxy and most others. It’s likely they existed as so-called “primordial” black holes in the earliest epochs of cosmic history. Yet, there seems to be a missing link category: intermediate-mass black holes (IMBH). Astronomers have searched for these rare beasts for years and there’s only one possible observation thanks to gravitational-wave data. So, where are they?

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Primordial Black Holes Can Only Explain a Fraction of Dark Matter

This artist's illustration shows what primordial black holes might look like. In reality, the black holes would struggle to form accretion disks. (But without them it would just be an illustration of black space.) Image Credit: NASA’s Goddard Space Flight Center

What is Dark Matter? That question is prominent in discussions about the nature of the Universe. There are many proposed explanations for dark matter, both within the Standard Model and outside of it.

One proposed component of dark matter is primordial black holes, created in the early Universe without a collapsing star as a progenitor.

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Where are All the Primordial Black Holes?

This graphic shows how large-amplitude fluctions on small scales in the cosmic background background could result in primordial black holes. Courtesy: ESA/Planck Collaboration/Jason Kristiano.
This graphic shows how large-amplitude fluctions on small scales in the cosmic background background could result in primordial black holes. Courtesy: ESA/Planck Collaboration/Jason Kristiano.

The earliest black holes in the Universe called primordial black holes (PBHs), are strong contenders to help explain why the Universe is heavier than it looks. There’s only one problem: these miniature monsters haven’t exactly been observed—yet. But, when astronomers do find them, they might turn out to be part of the Universe’s dark matter component.

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Hot Gas is Being Vented Away from the Center of the Milky Way

X-Ray Data Revealing Jets at the Center of the Milky Way Credit: X-ray: NASA/CXC/Univ. of Chicago/S.C. Mackey et al.; Radio: NRF/SARAO/MeerKAT; Image Processing: NASA/CXC/SAO/N. Wolk

Studying gas in the Universe is no easy task. We often look to ‘non-visible’ wavelengths of the electromagnetic spectrum such as X-rays. The Chandra X-Ray observatory has been observing a vent of hot gas blowing away from the centre of the Milky Way. Located about 26,000 light years away, the jet extends for hundreds of light years and is perpendicular to the disk of the Galaxy. It is now thought the gas has been forced away from the centre of the Milky Way because of a collision with cooler gas lying in its path and creating shockwaves. 

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Black Holes: Why study them? What makes them so fascinating?

Simulation of a black hole. (Credit: NASA/ESA/Gaia/DPAC)

Over the last few months, Universe Today has explored a plethora of scientific fields, including impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, planetary geophysics, cosmochemistry, meteorites, radio astronomy, extremophiles, and organic chemistry, and how these various disciplines help scientists and the public better understand our place in the cosmos.

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Hundreds of Massive Stars Have Simply Disappeared

This artist’s impression shows a possible seed for the formation of a supermassive black hole. Two of these possible seeds were discovered by an Italian team, using three space telescopes: the NASA Chandra X-ray Observatory, the NASA/ESA Hubble Space Telescope, and the NASA Spitzer Space Telescope.

The lifecycle of a star is regularly articulated as formation taking place inside vast clouds of gas and dust and then ending either as a planetary nebula or supernova explosion. In the last 70 years however, there seems to be a number of massive stars that are just disappearing! According to stellar evolution models, they should be exploding as supernova but instead, they just seem to vanish. A team of researchers have studied the behaviour of star VFTS 243 – a main sequence star with a black hole companion – and now believe it, like the others, have just collapsed, imploding into a black hole!

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Merging Black Holes Could Give Astronomers a Way to Detect Hawking Radiation

Simulation of merging supermassive black holes. Credit: NASA's Goddard Space Flight Center/Scott Noble

Nothing lasts forever, including black holes. Over immensely long periods of time, they evaporate, as will other large objects in the Universe. This is because of Hawking Radiation, named after Stephen Hawking, who developed the idea in the 1970s.

The problem is Hawking Radiation has never been reliably observed.

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A New Way to Measure the Rotation of Black Holes

Sometimes, astronomers get lucky and catch an event they can watch to see how the properties of some of the most massive objects in the universe evolve. That happened in February 2020, when a team of international astronomers led by Dheeraj (DJ) Pasham at MIT found one particular kind of exciting event that helped them track the speed at which a supermassive black hole was spinning for the first time.

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