Black Holes Archives

November 21, 2024November 21, 2024 by Matt Williams

New Study Suggests Black Holes Get their “Hair” from their Mothers

This artist’s impression of a supermassive black hole and accretion disk, along with a relativistic jet emanating from its poles. Credit & ©: ESO/L. Calçada

Despite decades of study, black holes are still one of the most puzzling objects in the Universe. As we know from Einstein’s Theory of General Relativity, the gravitational force of these stellar remnants alters the curvature of spacetime around them. This causes gas, dust, and even photons (light) in their vicinity to fall inwards and form disks that slowly accrete onto their faces, never to be seen again. However, astronomers have also noted that they can produce powerful jets that accelerate charged particles to close to the speed of light (aka. relativistic jets).

These jets lead to powerful gamma-ray bursts (GRBs), which have been observed with black holes that have powerful magnetic fields. However, where these magnetic fields come from has remained a mystery to astrophysicists for some time. According to new research led by scientists from the Flatiron Institute, the source of these fields may have finally been revealed. Based on a series of simulations they conducted that modeled the life cycle of stars from birth to collapse, they found that black holes inherit their magnetic fields from the parent stars themselves.

November 1, 2024November 1, 2024 by Mark Thompson

The Connection Between Black Holes and Dark Energy is Getting Stronger

JWST NIRCam imaging of star-forming protocluster PHz G191.24+62.04, 11 billion years ago as the universe was approaching the peak of star formation. These early galaxies are among the most active star-forming galaxies observed between 10.5 and 11.5 billion years ago. Each galaxy seen in this image is therefore producing many black holes, which are converting matter into dark energy according to the cosmologically coupled black hole hypothesis. This image shows the two "modules" of JWST NIRCam: The leftmost module contains the protocluster, and the rightmost module is an adjacent blank field. Each module sees thousands of galaxies.

The discovery of the accelerated expansion of the Universe has often been attributed to the force known as dark energy. An intriguing new theory was put forward last year to explain this mysterious force; black holes could be the cause of dark energy! The theory goes on to suggest as more black holes form in the Universe, the stronger the pressure from dark energy. A survey from the Dark Energy Spectroscopic Instrument (DESI) seems to support the theory. The data from the first year of operation shows the density of dark energy increases over time and seems to correlate with the number and mass of black holes!

September 4, 2024September 4, 2024 by Mark Thompson

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.

August 22, 2024August 22, 2024 by Matt Williams

New Study Proposes how a Black Hole in Orbit Around a Planet Could be a Sign of an Advanced Civilization.

Ray traced shadow of a spinning and charged black hole. Credit: Simon Tyran, CC BY-SA 4.0

In 1971, English mathematical physicist and Nobel-prize winner Roger Penrose proposed how energy could be extracted from a rotating black hole. He argued that this could be done by building a harness around the black hole’s accretion disk, where infalling matter is accelerated to close to the speed of light, triggering the release of energy in multiple wavelengths. Since then, multiple researchers have suggested that advanced civilizations could use this method (the Penrose Process) to power their civilization and that this represents a technosignature we should be on the lookout for.

Examples include John M. Smart’s Transcension Hypothesis, a proposed resolution to the Fermi Paradox where he suggested advanced intelligence may migrate to the region surrounding black holes to take advantage of the energy available. The latest comes from Harvard Professor Avi Loeb, who proposed in a recent paper how advanced civilizations could rely on a “Black Hole Moon” to provide their home planet with power indefinitely. The way this black hole would illuminate the planet it orbits, he argues, would constitute a potential technosignature for future SETI surveys.

August 13, 2024August 13, 2024 by Mark Thompson

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.

August 8, 2024August 8, 2024 by Evan Gough

The Aftermath of Neutron Star Mergers

An artistic rendering of two neutron stars merging. Credit: NSF/LIGO/Sonoma State/A. Simonnet

Neutron stars (NS) are the collapsed cores of supermassive giant stars that contain between 10 and 25 solar masses. Aside from black holes, they are the densest objects in the Universe. Their journey from a main sequence star to a collapsed stellar remnant is a fascinating scientific story.

Sometimes, a binary pair of NS will merge, and what happens then is equally as fascinating.

June 30, 2024June 30, 2024 by Mark Thompson

What’s Next for the Event Horizon Telescope? Twelve Possible New Targets

Both the Milky Way and a galaxy known as M87 have supermassive black holes at their core. These are the two largest black holes we know about and the Event Horizon Telescope has just captured stunning images of their event horizons. A new paper looks at what we might expect from a next generation EHT and highlights twelve targets that should be top of the list.

June 17, 2024June 17, 2024 by Andy Tomaswick

Baby Stars are Swarming Around the Galactic Center

The vicinity of Sagittarius A* (Sgr A*), the supermassive black hole at the Milky Way’s center, is hyperactive. Stars, gas, and dust zip around the black hole’s gravitational well at thousands of kilometers per hour. Previously, astronomers thought that only mature stars had been pulled into such rapid orbits. However, a new paper from the University of Cologne and elsewhere in Europe found that some relatively young stars are making the rounds rather than older ones, which raises some questions about the models predicting how stars form in these hyperactive regions.

June 5, 2024June 5, 2024 by Evan Gough

The JWST is Re-Writing Astronomy Textbooks

The first JWST Deep Field Image, showing large distant galaxies. The telescope's observations are revealing the previously unseen and are forcing a re-write of astronomy textbooks. Image Credit: NASA, ESA, CSA, STScI

When the James Webb Space Telescope was launched at the end of 2021, we expected stunning images and illuminating scientific results. So far, the powerful space telescope has lived up to our expectations. The JWST has shown us things about the early Universe we never anticipated.

Some of those results are forcing a rewrite of astronomy textbooks.

May 29, 2024May 29, 2024 by Laurence Tognetti

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.