Black Holes Archives

April 8, 2021April 8, 2021 by Brian Koberlein

An Intermediate-Mass Black Hole Discovered Through the Gravitational Lensing of a Gamma-ray Burst

An intermediate mass black hole lenses light around it. Credit: Carl Knox, OzGrav

Black holes come in three sizes: small, medium, and large. Small black holes are of stellar mass. They form when a large star collapses at the end of its life. Large black holes lurk in the centers of galaxies and are millions or billions of solar masses. Middle-sized black holes are those between 100 to 100,000 solar masses. They are known as Intermediate Mass Black Holes (IMBHs), and they are the kind we least understand.

March 27, 2021March 27, 2021 by Brian Koberlein

The Event Horizon Telescope has Revealed the Magnetic Field Lines Around M87's Central Black Hole

Computer simulation of plasma near a black hole. Credit: Hotaka Shiokawa / EHT

In 2019 astronomers captured the first direct image of a black hole. It was an image of the supermassive black hole at the heart of M87. And when many folks saw it, their reaction was “that’s it?” Which is understandable, given that the image is just a blurry, donut-shaped smudge. It isn’t much to look at. But an astronomical image is a small fraction of the data gathered by astronomers. Recently more of that data has been analyzed, including both the polarization of the light and the magnetic field surrounding the black hole.

March 11, 2021March 11, 2021 by Brian Koberlein

What's the Connection Between Stellar-Mass Black Holes and Dark Matter?

Artist view of a black hole in the middle of solar system. Credit: Petr Kratochvil/PublicDomainPictures CC0

Imagine you are a neutron star. You’re happily floating in space, too old to fuse nuclei in your core anymore, but the quantum pressure of your neutrons and quarks easily keeps you from collapsing under your own weight. You look forward to a long stellar retirement of gradually cooling down. Then one day you are struck by a tiny black hole. This black hole only has the mass of an asteroid, but it causes you to become unstable. Gravity crushes you as the black hole consumes you from the inside out. Before you know it, you’ve become a black hole.

March 10, 2021March 8, 2021 by Paul M. Sutter

Did Supermassive Black Holes Form Directly From Dark Matter?

This illustration depicts a gas halo surrounding a quasar in the early Universe. The quasar, in orange, has two powerful jets and a supermassive black hole at its centre, which is surrounded by a dusty disc. The gas halo of glowing hydrogen gas is represented in blue. A team of astronomers surveyed 31 distant quasars, seeing them as they were more than 12.5 billion years ago, at a time when the Universe was still an infant, only about 870 million years old. They found that 12 quasars were surrounded by enormous gas reservoirs: halos of cool, dense hydrogen gas extending 100 000 light years from the central black holes and with billions of times the mass of the Sun. These gas stashes provide the perfect food source to sustain the growth of supermassive black holes in the early Universe.

Supermassive black holes are just a little bit too supermassive – astronomers have difficulty explaining how they got so big so quickly in the early universe. So maybe it’s time for a new idea: perhaps giant black holes formed directly from dark matter.

February 24, 2021February 24, 2021 by Brian Koberlein

Cygnus X-1 was the First Black Hole Ever Found. New Measurements Show it's Much More Massive Than Previously Believed

An artist’s impression of the Cygnus X-1 system. Credit: International Centre for Radio Astronomy Research

In 1964 two Aerobee suborbital rockets were launched with the goal of mapping x-ray sources in the sky. Each rocket contained a directed Geiger counter, so that as the rocket rotated at the peak of its trajectory to measure the direction of x-ray sources. The project discovered eight x-ray sources, including a particularly bright one in the constellation Cygnus. It became known as Cygnus X-1.

Cygnus X-1 as imaged by a balloon bourne telescope. Credit: NASA/Marshall Space Flight Center

February 15, 2021February 15, 2021 by Brian Koberlein

A Cluster of Black Holes Found Inside a Globular Cluster of Stars

This image from the NASA/ESA Hubble Space Telescope shows the central region of the rich globular star cluster NGC 3201 in the southern constellation of Vela (The Sails). A star that has been found to be orbiting a black hole with four times the mass of the Sun is indicated with blue circle. Credit: ESA/NASA

Black holes come in at least two sizes: small and large. Small black holes are formed from stars. When a large star reaches the end of its life, it typically ends in a supernova. The remnant core then collapses under its own weight, forming a black hole or neutron star. Small stellar-mass black holes are typically tens of solar masses. Large black holes lurk in the centers of galaxies. These supermassive black holes can be millions or billions of solar masses. They formed during the early universe and triggered the formation and evolution of galaxies around them.

February 3, 2021February 3, 2021 by Brian Koberlein

Black Holes Simulated in a Tank of Water Reveals “Backreaction” for the First Time

This artist's concept shows the most distant supermassive black hole ever discovered. It is part of a quasar from just 690 million years after the Big Bang. Credit: Robin Dienel/Carnegie Institution for Science

It’s hard to make a black hole in the lab. You have to gather up a bunch of mass, squeeze it until it gravitationally collapses on itself, work, work, work. It’s so hard to do that we’ve never done it. We can, however, make a simulated black hole using a tank of water, and it can tell us interesting things about how black holes work.

February 2, 2021February 2, 2021 by Evan Gough

When Galaxies Collide, Black Holes Don’t Always Get the Feast They Were Hoping for

What happens when galaxies collide? Well, if any humans are around in about a billion years, they might find out. That’s when our Milky Way galaxy is scheduled to collide with our neighbour the Andromeda galaxy. That event will be an epic, titanic, collision. The supermassive black holes at the center of both galaxies will feast on new material and flare brightly as the collision brings more gas and dust within reach of their overwhelming gravitational pull. Where massive giant stars collide with each other, lighting up the skies and spraying deadly radiation everywhere. Right?

Maybe not. In fact, there might be no feasting at all, and hardly anything titanic about it.

January 23, 2021January 23, 2021 by Brian Koberlein

In Theory, Supermassive Black Holes Could get Even More Supermassive

Artist view of a stupendously large black hole. Credit: NASA, ESA, and D. Coe, J. Anders

Our universe contains some enormous black holes. The supermassive black hole in the center of our galaxy has a mass of 4 million Suns, but it’s rather small as galactic black holes go. Many galactic black holes have a billion solar masses, and the most massive known black hole is estimated to have a mass of nearly 70 billion Suns. But just how big can a black hole get?

January 5, 2021January 5, 2021 by Paul M. Sutter

Missing: Supermassive Black Hole With up to 100 BILLION Times the Mass of the Sun

The massive galaxy cluster Abell 2261 should have a supermassive black hole in its center. But it doesn’t. Astronomers have looked everywhere – even between the couch cushions. What’s going on?