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Astronomers Observe Star Being ‘Spaghettified’ by a Supermassive Black Hole

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Artist’s impression of a star undergoing spaghettification near a supermassive black hole.

Artist’s impression of a star undergoing spaghettification near a supermassive black hole.
Image: ESO

A star 215 million light-years away has been obliterated by a supermassive black hole, making it the closest observation to date of stellar spaghettification.

Spaghettification doesn’t sound very scientific, but it’s a fairly accurate description of what actually happens.

A doomed star caught in the orbit of a supermassive black hole will eventually hit a kind of gravitational sweet spot that turns everything to shit. No longer capable of keeping its physical integrity, the star begins to rapidly collapse in a process known as a fast-evolving tidal disruption event. When this happens, stellar debris bursts out from the star, forming a long, thin stream, half of which gets sucked toward the black hole; the other half is blown back into space. The thin stream eventually catches up to and slams into itself, releasing energy and forming an accretion disc. If that’s hard to visualize, here’s a video showing the process:

The destruction produces a bright flash of light, which astronomers can observe on Earth. A few of these events are captured each year, but new research published in Monthly Notices of the Royal Astronomical Society describes the nearest case of stellar spaghettification ever recorded, at 215 million light-years away. The event, designated AT2019qiz, was chronicled last year, and it appeared at the core of a spiral galaxy located in the Eridanus constellation. The unfortunate star was roughly the same size as our Sun, and it was torn apart by a supermassive black hole roughly 1 million times the Sun’s mass.

The event was initially captured by the Zwicky Transient Facility, with follow-up observations done with the European Southern Observatory’s Very Large Telescope, the ESO New Technology Telescope, and Harvard & Smithsonian’s MMT Observatory, among other

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New research suggests innovative method to analyse the densest star systems in the Universe

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New research suggests innovative method to analyse the densest star systems in the Universe
Artist’s illustration of supernova remnant Credit: Pixabay

In a recently published study, a team of researchers led by the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav) at Monash university suggests an innovative method to analyse gravitational waves from neutron star mergers, where two stars are distinguished by type (rather than mass), depending on how fast they’re spinning.


Neutron stars are extremely dense stellar objects that form when giant stars explode and die—in the explosion, their cores collapse, and the protons and electrons melt into each other to form a remnant neutron star.

In 2017, the merging of two neutron stars, called GW170817, was first observed by the LIGO and Virgo gravitational-wave detectors. This merger is well-known because scientists were also able to see light produced from it: high-energy gamma rays, visible light, and microwaves. Since then, an average of three scientific studies on GW170817 have been published every day.

In January this year, the LIGO and Virgo collaborations announced a second neutron star merger event called GW190425. Although no light was detected, this event is particularly intriguing because the two merging neutron stars are significantly heavier than GW170817, as well as previously known double neutron stars in the Milky Way.

Scientists use gravitational-wave signals—ripples in the fabric of space and time—to detect pairs of neutron stars and measure their masses. The heavier neutron star of the pair is called the ‘primary’; the lighter one is ‘secondary’.

The recycled-slow labelling scheme of a binary neutron star system

A binary neutron star system usually starts with two ordinary stars, each around ten to twenty times more massive than the Sun. When these massive stars age and run out of ‘fuel’, their lives end in supernova explosions that leave behind compact remnants, or neutron stars. Each remnant neutron star weighs around

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Astronomers see a black hole ‘spaghettify’ a star in real time

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Artist’s impression of star being tidally disrupted by a supermassive black hole.  


ESO/M. Kornmesser

It’s one of those astounding events that sounds like science fiction, but is just plain science. Astronomers say they were able to capture in unprecedented detail the process of a star being ripped into strips and devoured by a black hole. 

The powerful phenomenon caught the attention of scientists when a new blast of light near a known supermassive black hole was spotted by telescopes around the world. Months worth of follow-up observations made it clear they were seeing the destruction of a far-off sun as it happened.

“In this case the star was torn apart with about half of its mass feeding — or accreting — into a black hole of one million times the mass of the sun, and the other half was ejected outward,” explained astronomer Edo Berger from the Harvard-Smithsonian Center for Astrophysics, in a statement.  

The violent scene is what astronomers call a tidal disruption event, which happens when a star comes too close to a black hole and gets shredded through a process of spaghettification — basically, the gravity of the black hole is so intense that it stretches whatever comes near vertically into long, thin shapes like pieces of spaghetti as it swallows it all up. 

The event, which goes by the catalog entry AT2019qiz and is the closest such flare ever seen at just 215 million light-years away, was caught early enough that scientists have been able to get a relatively unobscured view of the cosmic carnage before a cloud of star guts pulls a veil over the region.

“We

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Walter Ashcraft, College Football Star and a Coach, Dies at 91

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Walter Ashcraft Jr., 6-foot-7 and 250 pounds by his early 20s, drew on his physique to excel in the Southern California sports world of the mid-20th century.

He placed third in the 1947 California high school shot-put championships, competing for Long Beach Polytechnic, finishing two places above Bob Mathias of Tulare High School, who captured a gold medal in the decathlon at the 1948 London Olympics.

Mr. Ashcraft also played at tackle for the University of Southern California football team. In his senior season, the Trojans, coached by Jess Hill, went 10-1, losing only to Notre Dame, and defeated Wisconsin, 7-0, in the 1953 New Year’s Day Rose Bowl game.

The N.F.L.’s Washington Redskins drafted him in 1953, one of 15 U.S.C. players who were selected.

He received a $5,000 signing bonus from the Redskins, but incurred a knee injury in training camp and never played in an N.F.L. game. Since pro football salaries were modest, he decided to pursue a career elsewhere.

He obtained a master’s degree in education and devoted himself to coaching and hospitality work.

Mr. Ashcraft died on Aug. 18 in Anderson, S.C., of pneumonia stemming from Covid-19, his family said. He was 91.

He had been living at a military veterans’ retirement home with his wife, Betty Jo (Carrera) Ashcraft. During the Korean War, he interrupted his time at U.S.C. to enlist in the Marine Corps, played for a Marine football team in California and was discharged as a sergeant.

Walter White Ashcraft, Jr. was born on Aug. 11, 1929, in Amory, Miss., where his father owned a gas station. His mother, Corinne (Austin) Ashcraft, was a homemaker. One day, when he was 11 or so, his father came upon the aftermath of a lynching — three Black men hanging from a tree.

“He couldn’t

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Astronomers find x-rays lingering years after landmark neutron star collision

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UMD astronomers find x-rays lingering years after landmark neutron star collision
Researchers have continuously monitored the radiation emanating from the first (and so far only) cosmic event detected in both gravitational waves and the entire spectrum of light. The neutron star collision detected on August 17, 2017, is seen in this image emanating from galaxy NGC 4993. New analysis provides possible explanations for X-rays that continued to radiate from the collision long after other radiation had faded and way past model predictions. Credit: E. Troja

It’s been three years since the landmark detection of a neutron star merger from gravitational waves. And since that day, an international team of researchers led by University of Maryland astronomer Eleonora Troja has been continuously monitoring the subsequent radiation emissions to provide the most complete picture of such an event.


Their analysis provides possible explanations for X-rays that continued to radiate from the collision long after models predicted they would stop. The study also reveals that current models of neutron stars and compact body collisions are missing important information. The research was published on October 12, 2020, in the journal Monthly Notices of the Royal Astronomical Society.

“We are entering a new phase in our understanding of neutron stars,” said Troja, an associate research scientist in UMD’s Department of Astronomy and lead author of the paper. “We really don’t know what to expect from this point forward, because all our models were predicting no X-rays and we were surprised to see them 1,000 days after the collision event was detected. It may take years to find out the answer to what is going on, but our research opens the door to many possibilities.

The neutron star merger that Troja’s team studied—GW170817—was first identified from gravitational waves detected by the Laser Interferometer Gravitational-wave Observatory and its counterpart Virgo on August 17, 2017. Within hours, telescopes

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