The Milky Way’s Supermassive Black Hole Might Have Formed 9 Billion Years Ago

This is the first image of Sgr A*, the supermassive black hole at the center of our galaxy. A reanalysis of EHT data by NAOJ scientist suggests its accretion disk may be more elongated than shown in this image. Image Credit: EHT
This is the first image of Sgr A*, the supermassive black hole at the center of our galaxy. A reanalysis of EHT data by NAOJ scientist suggests its accretion disk may be more elongated than shown in this image. Image Credit: EHT

Large galaxies like ours are hosts to Supermassive Black Holes (SMBHs.) They can be so massive that they resist comprehension, with some of them having billions of times more mass than the Sun. Ours, named Sagittarius A* (Sgr A*), is a little more modest at about four million solar masses.

Astrophysicists have studied Sgr A* to learn more about it, including its age. They say it formed about nine billion years ago.

Continue reading “The Milky Way’s Supermassive Black Hole Might Have Formed 9 Billion Years Ago”

Simulating the Accretion Disk Around a Black Hole

Supercomputer simulations reveals the nature of turbulence in black hole accretion disks

Black holes are by their very nature, challenging to observe and difficult to spot. It’s usually observations of the accretion disk that reveal properties of the hidden black hole. There is often enough material within the accretion disk to make them shine so brightly that they can often be among the brightest objects in space. A wonderful image has been released which shows the highest resolution simulation of a black hole accretion disk ever created. 

Continue reading “Simulating the Accretion Disk Around a Black Hole”

The Surprising Source of Radiation Coming From Black Holes

A visualization of how turbulent plasma moves through a black hole accretion disk threaded with strong magnetic fields. Image credit: Jani Narhi.
A visualization of how turbulent plasma moves through a black hole accretion disk threaded with strong magnetic fields. Image credit: Jani Närhi.

Black holes are famous for sucking in everything that crosses their event horizons, including light. So, why do astronomers see energetic radiation coming from the environment of a black hole in an X-ray binary system? It’s a good question that finally has an answer.

Continue reading “The Surprising Source of Radiation Coming From Black Holes”

Dark Matter Could Have Driven the Growth of Early Supermassive Black Holes

An image from the Event Horizon Telescope shows lines of polarization, a signature of magnetic fields, around the shadow of the Milky Way's central supermassive black hole. Astronomers want to know how massive black holes like this one formed early in cosmic history. (Credit: EHT Collaboration)
An image from the Event Horizon Telescope shows lines of polarization, a signature of magnetic fields, around the shadow of the Milky Way's central supermassive black hole. Astronomers want to know how massive black holes like this one formed early in cosmic history. (Credit: EHT Collaboration)

The James Webb Space Telescope (JWST) keeps finding supermassive black holes (SMBH) in the early Universe. They’re in active galactic nuclei seen only 500,000 years after the Big Bang. This was long before astronomers thought they could exist. What’s going on?

Continue reading “Dark Matter Could Have Driven the Growth of Early Supermassive Black Holes”

A New Test Proves How to Make the Event Horizon Telescope Even Better

This image shows the Atacama Large Millimeter/submillimeter Array (ALMA) looking up at the supermassive black hole at our galactic centre. ALMA is part of the Event Horizon Telescope. Courtesy EHT.
This image shows the Atacama Large Millimeter/submillimeter Array (ALMA) looking up at the supermassive black hole at our galactic centre. ALMA is part of the Event Horizon Telescope. Courtesy EHT and ESO.

Want a clear view of a supermassive black hole’s environment? It’s an incredible observational challenge. The extreme gravity bends light as it passes through and blurs the details of the event horizon, the region closest to the black hole. Astronomers using the Event Horizon Telescope (EHT) just conducted test observations aimed at “deblurring” that view.

Continue reading “A New Test Proves How to Make the Event Horizon Telescope Even Better”

We Know When a Black Hole Will Have its Next Feast

Black holes are notoriously destructive to stars near them. Astronomers often see flashes representing the death throes of stars collapsing past the event horizon, a black hole they got too close to. However, in rare instances, a star isn’t wholly swallowed by its gigantic neighbor and is pulled into an orbit, causing a much slower death, which would probably be more painful if stars could feel anything. A new study using X-ray results from Chandra and some other instruments details a supermassive black hole at the center of a galaxy far, far away that is slowly devouring a star it has captured in an orbit, and it could teach them more about a variety of interest physical processes. 

Continue reading “We Know When a Black Hole Will Have its Next Feast”

Primordial Black Holes Could Kick Out Stars and Replace Them.

This artist's illustration shows what primordial black holes might look like. In reality, the black holes would struggle to form accretion disks, as shown. Image Credit: NASA’s Goddard Space Flight Center

Primordial black holes formed during the earliest stages of the evolution of the universe. Their immense gravity may be playing havoc in stellar systems. They can transfer energy into wide binary systems disrupting their orbits. Like celestial bullies their disruption might lead to extreme outcomes though like the ejection of a star, only to be replaced by the black hole itself! A new paper studies the interactions of systems like these and looks at ways we might be able to detect them. 

Continue reading “Primordial Black Holes Could Kick Out Stars and Replace Them.”

Scientists Develop a Novel Method for Detecting Supermassive Black Holes: Use Smaller Black Holes!

A simulation of two merging black holes. Credit: Simulating eXtreme Spacetimes (SXS) Project

In 1974, astronomers Bruce Balick and Robert L. Brown discovered a powerful radio source at the center of the Milky Way galaxy. The source, Sagittarius A*, was subsequently revealed to be a supermassive black hole (SMBH) with a mass of over 4 million Suns. Since then, astronomers have determined that SMBHs reside at the center of all galaxies with highly active central regions known as active galactic nuclei (AGNs) or “quasars.” Despite all we’ve learned, the origin of these massive black holes remains one of the biggest mysteries in astronomy.

The most popular theories are that they may have formed when the Universe was still very young or have grown over time by consuming the matter around them (accretion) and through mergers with other black holes. In recent years, research has shown that when mergers between such massive objects occur, Gravitational Waves (GWs) are released. In a recent study, an international team of astrophysicists proposed a novel method for detecting pairs of SMBHs: analyzing gravitational waves generated by binaries of nearby small stellar black holes.

Continue reading “Scientists Develop a Novel Method for Detecting Supermassive Black Holes: Use Smaller Black Holes!”

The JWST Reveals the Nature of Dust Around an Active Galactic Nuclei

The James Webb Space Telescope captured this three colour image of the galaxy ESO 428-G14. New research shows how the dust near the galaxy's supermassive black hole is heated up. Image Credit: NASA, ESA, CSA, and STScI

Supermassive Black Holes (SMBHs) are located in the centers of large galaxies like ours. When they’re actively feeding, they produce more light and are called active galactic nuclei (AGN). But their details are difficult to observe clearly because large clouds of gas block our view.

The JWST was built just for circumstances like these.

Continue reading “The JWST Reveals the Nature of Dust Around an Active Galactic Nuclei”