Gamma Ray Bursts 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.

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.

October 27, 2023October 27, 2023 by Laurence Tognetti

JWST Confirms the Formation of Heavy Elements in a Kilonova

Image from JWST’s Near-Infrared Camera (NIRCam) instrument displaying GRB 230307A’s kilonova and its former home galaxy, the former of which was found to possess heavy elements. (Credit: NASA, ESA, CSA, STScI, A. Levan (IMAPP, Warw), A. Pagan (STScI))

A recent study published in Nature investigates recent observations from NASA’s James Webb Space Telescope (JWST) and ground-based telescopes of heavy elements within the ejected material of a recent gamma-ray burst (GRB), classified as GRB 230307A, that was likely produced by a kilonova with GRB 230307A being designated as the second-brightest GRB ever detected. The heavy element in question is the chemical element tellurium, which is classified as a metalloid on the periodic table. However, scientists also hypothesize that the element iodine, which is a requirement for most of life on the Earth and classified as a reactive nonmetal, could also exist within the kilonova’s explosion, with both elements residing side-by-side on the periodic table.

April 6, 2023April 6, 2023 by David Dickinson

Brightest Gamma-ray Burst Shines Light on Milky Way Structure

GRB Burst — XMM Newton's view of the remnant of the record-setting gamma-ray burst 221009A. ESA

The brightest gamma-ray burst ever seen in 2022 still puzzles astronomers.

The more researchers look at a recent record-setting event, the stranger it gets.

The story begins on the evening of October 9^th, 2022, when NASA’s Neil Gehrels Swift orbiting observatory detected a strong X-ray outburst. The source was in the direction of the constellation of Sagitta the Arrow along the galactic plane, suggesting a source in our own Milky Way galaxy. Follow-up observations from NASA’s Fermi Gamma-Ray Space Telescope and the Earth-based European Southern Observatory’s Very Large Telescope however, soon revealed that the source was much more distant, emanating from a gamma-ray burst lying beyond our galaxy. This outburst only appeared to have happened along our line of sight as seen through the plane own galaxy from our Earthbound perspective.

December 7, 2022December 7, 2022 by Evan Gough

Colliding Neutron Stars can Generate Long Gamma-ray Bursts

Artist's illustration of a bright gamma-ray burst occurring in a star-forming region and beaming out energy into two narrow, oppositely directed jets. Image Credit: By NASA/Swift/Mary Pat Hrybyk-Keith and John Jones - http://imagine.gsfc.nasa.gov/docs/features/news/10sep08.html [1]Transferred from en.wikipedia to Commons by TheDJ using CommonsHelper., Public Domain, https://commons.wikimedia.org/w/index.php?curid=8807284

Gamma-Ray Bursts (GRBs) are the most energetic recurring events in the Universe. Only the Big Bang was more energetic, and it was a singularity. Astronomers see GRBs in distant Universes, and a lot of research has gone into understanding them and what causes them.

A new paper is upending some of what scientists thought they knew about these extraordinary explosions.

December 7, 2022December 7, 2022 by Paul M. Sutter

How Artificial Intelligence Can Find the Source of Gamma-Ray Bursts

Gamma-ray bursts (GRBs) are powerful flashes of energetic gamma-rays lasting from less than a second to several minutes. They release a tremendous amount of energy in this short time making them the most powerful events in the Universe. They are thought to be mostly associated with the explosion of stars that collapse into black holes. In the explosion, two jets of very fast-moving material are ejected, as depicted in this artist’s illustration. If a jet happens to be aimed at Earth, we see a brief but powerful gamma-ray burst. Credit: ESO/A. Roquette

Gamma-ray bursts come in two main flavors, short and long. While astronomers believe that they understand what causes these two kinds of bursts, there is still significant overlap between them. A team of researchers have proposed a new way to classify gamma-ray bursts using the aid of machine learning algorithms. This new classification scheme will help astronomers better understand these enigmatic explosions.

December 6, 2022December 7, 2022 by Seth Lockman

A new Hubble Image Reveals a Shredded Star in a Nearby Galaxy

The latest composite image of supernova remnant DEM L 190, released in November 2022. Credit: ESA/Hubble & NASA, S. Kulkarni, Y. Chu

The Hubble Space Telescope, to which we owe our current estimates for the age of the universe and the first detection of organic matter on an exoplanet, is very much doing science and still alive. It’s latest masterpiece remixes an old hit – apparently a growing trend in space science as well as space music.

October 19, 2022October 19, 2022 by Matt Williams

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.

July 28, 2022July 28, 2022 by Matt Williams

A Black Hole can Tear a Neutron Star Apart in Less Than 2 Seconds

Numerical simulation of a black hole-neutron star merger. Credit and ©: K. Hayashi (Kyoto University)

Almost seven years ago (September 14th, 2015), researchers at the Laser Interferometer Gravitational-wave Observatory (LIGO) detected gravitational waves (GWs) for the first time. Their results were shared with the world six months later and earned the discovery team the Noble Prize in Physics the following year. Since then, a total of 90 signals have been observed that were created by binary systems of two black holes, two neutron stars, or one of each. This latter scenario presents some very interesting opportunities for astronomers.

If a merger involves a black hole and neutron star, the event will produce GWs and a serious light display! Using data collected from the three black hole-neutron star mergers we’ve detected so far, a team of astrophysicists from Japan and Germany was able to model the complete process of the collision of a black hole with a neutron star, which included everything from the final orbits of the binary to the merger and post-merger phase. Their results could help inform future surveys that are sensitive enough to study mergers and GW events in much greater detail.

July 23, 2022July 23, 2022 by Brian Koberlein

Gamma-ray Bursts can Help Astronomers Measure Vast Distances Across the Universe

An illustration of a powerful gamma ray burst. Credit: NAOJ

Now that the James Webb Space Telescope is operational, astronomers can study some of the most faint and distant galaxies ever seen. By some accounts, we may have already captured the image of a galaxy from when the universe was just 300 million years old. But we can’t be entirely sure of its distance, and that is a big problem for astronomers.