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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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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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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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Astronomers just spotted a planet floating freely in space without a star

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  • Scientists have used gravitational lensing to detect a so-called ‘rogue planet’ that doesn’t orbit a star and floats freely in space.
  • The planet is relatively small, but researchers can’t tell for certain how far away it is from Earth.
  • It’s possible that the Milky Way is home to trillions of these free planets.

We think of our solar system as typical, or even “normal,” but in the universe, there’s really no such thing as normal. So many circumstances exist with regard to planets, stars, moons, and other objects that there’s no clear arrangement that the cosmos favors over any other, and there are even free-floating “rogue planets” that have escaped the systems they developed in and are just sort of doing their own thing.



fireworks in the night sky: rogue planet


© Provided by BGR
rogue planet


A new discovery of one such rogue planet was just described in a lengthy research paper. The planet was spotted by two teams, one working with OGLE, the Optical Gravitational Lensing Experiment, and KMTN, the Korean Microlensing Telescope Network. The only problem? Nobody really knows how far away the mysterious planet is.

As you may have gleaned from the name of the two projects that yielded the discovery, the planet was found with the help of a technique called gravitational lensing. Gravity acts on everything, including light, and scientists have been able to use this to their advantage by using a distant light source and some object in between it and Earth as a sort of invisible magnifying glass.

Gravity can bend light around a planet, allowing us to see that light even though something in between is blocking our direct line-of-sight. In this case, the mysterious rogue planet acted as the lens, revealing light “behind” it and cluing scientists into its presence. Because the planet in this particular case