A Black Hole is Savoring its Meal, Feeding on the Same Star Over and Over Again

This illustration shows a glowing stream of material from a star, being devoured and torn to shreds by a supermassive black hole. Credit: NASA/JPL-Caltech

Something extraordinary happens about every 10,000 to 100,000 years in galaxies like the Milky Way. An unwary star approaches the supermassive black hole (SMBH) at the galaxy’s center and is torn apart by the SMBH’s overpowering gravity. Astronomers call the phenomenon a tidal disruption event (TDE.)

Usually, a TDE spells doom for the star as its gas is torn away into the black hole’s accretion ring, causing a bright flaring visible for hundreds of millions of light years. But researchers have found one black hole that’s playing with its food.

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The JWST is the Shiny New Space Telescope, but the Dependable Hubble is Still Going Strong

The scattered stars of the globular cluster NGC 6355 are strewn across this image from the NASA/ESA Hubble Space Telescope. This globular cluster lies less than 50,000 light-years from Earth in the Ophiuchus constellation. Image Credit: ESA/Hubble & NASA, E. Noyola, R. Cohen

The Venerable Hubble Space Telescope has cemented its place in history. Some call it the most successful science experiment ever. And while the James Webb Space Telescope might vie for that title, the Hubble does things that even the powerful JWST can’t do.

Exhibit A: this stunning image of NGC 6355.

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What Does it Take to Make Black Holes Collide?

Simulation of the emitted light from a supermassive black hole binary system. (Credit: NASA’s Goddard Space Flight Center)

In a recent study published in Astronomy and Astrophysical Letters, a team of researchers at the Massachusetts Institute of Technology (MIT) used various computer models to examine 69 confirmed binary black holes to help determine their origin, and found their data results changed based on the model’s configurations, and the researchers wish to better understand both how and why this occurs and what steps can be taken to have more consistent results.

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Did Supermassive Black Holes Collapse Directly out of Giant Clouds of gas? It Could Depend on Magnetic Fields

This artist’s impression shows a possible seed for the formation of a supermassive black hole. Credit: NASA/CXC/M. Weiss

Roughly half a century ago, astronomers realized that the powerful radio source coming from the center of our galaxy (Sagitarrius A*) was a “monster” black hole. Since then, they have found that supermassive black holes (SMBHs) reside at the center of most massive galaxies. This leads to what is known as Active Galactic Nuclei (AGN) or quasars, where the central region of a galaxy is so energetic that it outshines all of the stars in its galactic disk. In all that time, astronomers have puzzled over how these behemoths (which play a crucial role in galactic evolution) originated.

Astronomers suspect that the seeds that formed SMBHs were created from giant clouds of dust that collapsed without first becoming stars – aka. Direct Collapse Black Holes (DCBHs). However, the role of magnetic fields in the formation of DCBHs has remained unclear since none of the previous studies have been able to simulate the full accretion periods. To investigate this, an international team of astronomers ran a series of 3D cosmological magneto-hydrodynamic (MHD) simulations that accounted for DCBH formation and showed that magnetic fields grow with the accretion disks and stabilize them over time.

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A Black Hole is Hurling a jet of Material at its Neighboring Galaxy

Artist view of an active supermassive black hole. Credit: ESO/L. Calçada

It’s been a banner time for black hole research! In recent months, astrophysicists have announced the discovery of the most powerful gamma-ray burst ever recorded (due to the formation of a black hole), a monster black hole in our cosmic backyard, the frame-dragging effects of a binary black hole, and the remains of the 2017 Kilonova event (spoiler alert: it was a black hole). And with the help of citizen scientists, a team of astronomers recently discovered a unique black hole in a galaxy roughly one billion light-years away that’s hurling a relativistic jet at another galaxy.

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A Monster Black Hole has Been Found Right in our Backyard (Astronomically Speaking)

The cross-hairs mark the location of the newly discovered monster black hole. Credit: Sloan Digital Sky Survey/S. Chakrabart et al.

Black holes are among the most awesome and mysterious objects in the known Universe. These gravitational behemoths form when massive stars undergo gravitational collapse at the end of their lifespans and shed their outer layers in a massive explosion (a supernova). Meanwhile, the stellar remnant becomes so dense that the curvature of spacetime becomes infinite in its vicinity and its gravity so intense that nothing (not even light) can escape its surface. This makes them impossible to observe using conventional optical telescopes that study objects in visible light.

As a result, astronomers typically search for black holes in non-visible wavelengths or by observing their effect on objects in their vicinity. After consulting the Gaia Data Release 3 (DR3), a team of astronomers led by the University of Alabama Huntsville (UAH) recently observed a black hole in our cosmic backyard. As they describe in their study, this monster black hole is roughly twelve times the mass of our Sun and located about 1,550 light-years from Earth. Because of its mass and relative proximity, this black hole presents opportunities for astrophysicists.

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Astronomers Just saw the Most Powerful Gamma-ray Burst Ever Recorded

Artist’s impression of a gamma-ray burst. Credit: ESO/A. Roquette

Gamma-ray bursts (GRBs) are one of the most mysterious transient phenomena facing astronomers today. These incredibly energetic bursts are the most powerful electromagnetic events observed since the Big Bang and can last from a few milliseconds to many hours. Whereas longer bursts are thought to occur during supernovae, when massive stars undergo gravitational collapse and shed their outer layer to become black holes, shorter events have also been recorded when massive binary objects (black holes and neutron stars) merge.

These bursts are characterized by an initial flash of gamma rays and a longer-lived “afterglow” typically emitted in X-ray, ultraviolet, radio, and other longer wavelengths. In the early-morning hours on October 14th, 2022, two independent teams of astronomers using the Gemini South telescope observed the aftermath of a GRB designated GRB221009A. Located 2.4 billion light-years away in the Sagitta constellation, this event was perhaps the closes and most powerful explosion ever recorded and was likely triggered by a supernova that gave birth to a black hole.

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A Black Hole Burps out Material, Years After Feasting on a Star

. Credit: DESY/Science Communication Lab

Originally predicted by Einstein’s Theory of General Relativity, black holes are the most extreme object in the known Universe. These objects form when stars reach the end of their life cycle, blow off their outer layers, and are so gravitationally powerful that nothing (not even light) can escape their surfaces. They are also of interest because they allow astronomers to observe the laws of physics under the most extreme conditions. Periodically, these gravitational behemoths will devoir stars and other objects in their vicinity, releasing tremendous amounts of light and radiation.

In October 2018, astronomers witnessed one such event when observing a black hole in a galaxy located 665 million light-years from Earth. While astronomers have witnessed events like this before, another team from the Harvard & Smithsonian Center for Astrophysics noticed something unprecedented when they examined the same black hole three years later. As they explained in a recent study, the black hole was shining very brightly because it was ejecting (or “burping”) leftover material from the star at half the speed of light. Their findings could provide new clues about how black holes feed and grow over time.

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The Milky Way is Surrounded by a Vast Graveyard of Dead Stars

Distribution of stellar remains in the Milky Way. Credit: University of Sydney

Everything dies in the end, even the brightest of stars. In fact, the brightest stars are the ones that live the shortest lives. They consume all the hydrogen they have within a few million years, then explode as brilliant supernovae. Their core remains collapse into a neutron star or black hole. These small, dark objects litter our galaxy, like a cosmic graveyard.

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Astronomers Find a Sun-like Star Orbiting a Nearby Black Hole

Gaia BH1 is a Sun-like star co-orbiting with a black hole estimated at 10 times the Sun's mass. Credit: ESO/L. Calcada

In 1916, Karl Schwarzchild theorized the existence of black holes as a resolution to Einstein’s field equations for his Theory of General Relativity. By the mid-20th century, astronomers began detecting black holes for the first time using indirect methods, which consisted of observing their effects on surrounding objects and space. Since the 1980s, scientists have studied supermassive black holes (SMBHs), which reside at the center of most massive galaxies in the Universe. And by April 2019, the Event Horizon Telescope (EHT) collaboration released the first image ever taken of an SMBH.

These observations are an opportunity to test the laws of physics under the most extreme conditions and offer insights into the forces that shaped the Universe. According to a recent study, an international research team relied on data from the ESA’s Gaia Observatory to observe a Sun-like star with strange orbital characteristics. Due to the nature of its orbit, the team concluded that it must be part of a black hole binary system. This makes it the nearest black hole to our Solar System and implies the existence of a sizable population of dormant black holes in our galaxy.

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