Black Holes Archives

November 4, 2024November 4, 2024 by Brian Koberlein

Another Way to Extract Energy From Black Holes?

Illustration of a powerful black hole and its magnetic field. Credit: L. Calçada/ESO

The gravitational field of a rotating black hole is powerful and strange. It is so powerful that it warps space and time back upon itself, and it is so strange that even simple concepts such as motion and rotation are turned on their heads. Understanding how these concepts play out is challenging, but they help astronomers understand how black holes generate such tremendous energy. Take, for example, the concept of frame dragging.

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!

October 25, 2024October 25, 2024 by Carolyn Collins Petersen

The Milky Way’s Supermassive Black Hole Photo Might Need a Retake

Radio image of Sagittarius A* black hole in the center of the Milky Way galaxy, obtained from re-analysis by new research. The structure is elongated from east to west. The east side is bright and the west side is dark, which the research team interprets to mean that the east side is moving towards us. Credit Miyoshi et al. — Radio image of Sagittarius A* black hole in the center of the Milky Way galaxy, obtained from re-analysis by new research. The structure is elongated from east to west. The east side is bright and the west side is dark, which the research team interprets to mean that the east side is moving towards us. Credit: Miyoshi et al.

Remember that amazing “first image” of Sagittarius A* (Sgr A) black hole at the heart of the Milky Way? Well, it may not be completely accurate, according to researchers at the National Astronomical Observatory of Japan (NAOJ). Instead, the accretion disk around Sgr A* may be more elongated, rather than the circular shape we first saw in 2022.

October 24, 2024October 24, 2024 by Brian Koberlein

The First Triple Star System Found Containing a Black Hole

V404 Cygni in the process of consuming a nearby star while a second star orbits at a distance. Credit: Jorge Lugo

Neutron stars and black holes are the remnants of dead stars. They typically form as part of a supernova explosion, where the outer layers of an old star are violently cast off while the core of the star collapses to form the remnant. This violent origin can have significant consequences for both the remnant and the surrounding environment.

October 11, 2024October 11, 2024 by Brian Koberlein

A Black Hole has Destroyed a Star, and Used the Wreckage to Pummel Another Star

Illustration of a tidal disruption event. Credit: NASA/CXC/SAO and Soheb Mandhai/The Astro Phoenix

When a supermassive black hole consumes a star, it doesn’t just swallow it whole. It shreds the star, ripping it apart bit by bit before consuming the remains. It’s a messy process known as a tidal disruption event (TDE). Astronomers occasionally catch a glimpse of TDEs, and one recent one has helped solve a mystery about a type of transient X-ray source.

October 6, 2024October 6, 2024 by Matt Williams

Primordial Holes Could be Hiding in Planets, Asteroids, and Here on Earth

An artistic take on primordial black holes. Credit: NASA’s Goddard Space Flight Center

Small primordial black holes (PBHs) are one of the hot topics in astronomy and cosmology today. These hypothetical black holes are believed to have formed soon after the Big Bang, resulting from pockets of subatomic matter so dense that they underwent gravitational collapse. At present, PBHs are considered a candidate for dark matter, a possible source of primordial gravitational waves, and a resolution to various problems in physics. However, no definitive PBH candidate has been observed so far, leading to proposals for how we may find these miniature black holes.

Recent research has suggested that main-sequence neutron and dwarf stars might contain small PBHs in their interiors that are slowly consuming their gas supply. In a recent study, a team of physicists extended this idea to include a new avenue for potentially detecting PBHs. Basically, we could search inside objects like planets and asteroids or employ large plates or slabs of metal to detect PBHs for signs of their passage. By detecting the microchannels these bodies would leave, scientists could finally confirm the existence of PBHs and shed light on some of the greatest mysteries in cosmology today.

September 22, 2024September 22, 2024 by Brian Koberlein

Researchers Mimic Extracting Energy From Black Holes in the Lab

Illustration of a rapidly rotating black hole. Credit: ESO, ESA/Hubble, M. Kornmesser

When you get close to a black hole, things can get pretty intense. The tremendous gravity can squeeze gas to ionizing temperatures, and fierce magnetic fields can accelerate plasma into jets speeding at nearly the speed of light. That’s a lot of power, and wherever there is power someone will figure out how to harness it.

September 21, 2024September 21, 2024 by Mark Thompson

Astronomers Find the Longest Black Hole Jets Ever Seen

An artist's illustration of the longest black hole jet system ever observed.

Black holes often appear in science fiction movies, largely because elements of their existence are still a mystery. They have fascinating impacts on the surrounding region of space too with distortions in space and time high on the list. A team of astronomers have found a supermassive black hole with twin jets blasting out an incredible 23 million light years, the longest yet. To put this into context, if you lined up 140 Milky Way galaxies side by side, then that’s the length of the jet!

September 18, 2024September 18, 2024 by Evan Gough

The Early Universe Had a Lot of Black Holes

The Hubble Ultra Deep Field seen in ultraviolet, visible, and infrared light. Image Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)

The Hubble Deep Field and its successor, the Hubble Ultra-Deep Field, showed us how vast our Universe is and how it teems with galaxies of all shapes and sizes. They focused on tiny patches of the sky that appeared to be empty and revealed the presence of countless galaxies. Now, astronomers are using the Hubble Ultra-Deep Field and follow-up images to reveal the presence of a large number of supermassive black holes in the early Universe.

This is a shocking result because, according to theory, these massive objects shouldn’t have been so plentiful billions of years ago.

September 18, 2024September 20, 2024 by Evan Gough

A Star Was Kicked Out of a Globular Cluster by an Intermediate-Mass Black Hole

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

Astronomers have solid evidence for the existence of stellar-mass black holes and supermassive black holes. However, evidence for Intermediate Black Holes (IMBHs) is more elusive. Their existence remains hypothetical.

However, study by study, evidence is accumulating for IMBHs. The latest comes from the globular cluster M15, where a fast-moving star suggests the presence of something massive. Could it be an elusive IMBH?