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Walmart Black Friday: Stores limited to 20% capacity for 3-day event

  • Walmart said Wednesday it would stagger the launch of in-store Black Friday sales across three days in November to avoid crowds.
  • It will also limit store capacity to just 20% during its Black Friday sales, Bloomberg reported.
  • The first Black Friday event will focus on toys, electronics, and home products.
  • The retailer will launch discounts online first, and then bring them to stores at least two days later, it said.
  • Visit Business Insider’s homepage for more stories.

Walmart will split its Black Friday in-store sales over three days in November to avoid overcrowding, it said Wednesday.

It will also limit the number of Black Friday shoppers to just 20% of store capacity, Bloomberg reported.

The retailer said it would launch in-store sales events on November 7, 14, and 27, when stores will open at 5 a.m..

To avoid shoppers rushing to stores, Walmart is launching each set of discounts online at least two days early, it said in a press release.

It is also offering contact-free curbside pickup for online Black Friday orders.

The first Black Friday sale, starting online on November 4 and in stores on November 7, will focus on toys, electronics, and home products.

The second event will be for TVs, smartphones, and tablets. It will launch online on November 11, and in stores on November 14. 

The third event will offer discounts on a range of goods, from apparel to electronics. It will begin online on November 25, and in stores on November 27.

Walmart said it would separately hold its biggest phone sale event in-store and online on November 14, with deals on iPhones and Samsung phones.

Other deals available over the Black Friday period include an 42-inch UHD Roku TV for $88.

Read more: Retailers are struggling to attract seasonal workers for what experts anticipate will be a ‘tough holiday season’

On the Black Friday in-store event days, customers will have to form a line to enter the store. Staff will sanitize shopping carts and remind customers to wear masks, it said.

Spreading out in-store deals and making them available online earlier should make stores “safer and more manageable for both our customers and our associates,” Scott McCall, executive vice-president and chief merchandising officer at Walmart, said.

Walmart will also hold its annual Black Friday discount tire event both in-store and online between November 7 and 13, it said. 

Walmart announced in July it would keep all its stores closed on Thanksgiving Day for the first time since the 1980s. The day typically draws huge crowds to Walmart’s stores, with some Black Friday deals launching on that day.

Nearly two in five Americans plan to reduce their budget for Black Friday shopping this year, according to a survey released Tuesday by market research firm Piplsay.

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

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 handy 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 facilities. Astronomers tracked the fading flare for six months. The new paper was led by Matt Nicholl, a research fellow at the University of Birmingham.

Spaghettified stars tend to be hard to study because they’re often clouded by copious amounts of dust and debris. Thankfully, that was not the case with AT2019qiz.

The researchers found that, “when a black hole devours a star, it can launch a powerful blast of material outwards that obstructs our view,” explained Samantha Oates, an astronomer at the University of Birmingham, in an ESO statement. In this case, however, AT2019qiz was spotted shortly after the star was ripped apart, providing a clear view of the phenomenon.

“Because we caught it early, we could actually see the curtain of dust and debris being drawn up as the black hole launched a powerful outflow of material with velocities up to 10,000 km/s [6,200 miles/second],” said study co-author and Northwestern University astronomer Kate Alexander in a Harvard & Smithsonian press release. “This is a unique ‘peek behind the curtain’ that provided the first opportunity to pinpoint the origin of the obscuring material and

Scientists Watch a Black Hole Eat a Star

  • Astronomers have witnessed a tidal disruption event, where a star whose material was shredded by a nearby supermassive black hole releases an bright flash of light.
  • The TDE is helping scientists understand more about the gruesome spaghettification process.
  • The flare occurred just 215 million light-years away from Earth, closer than any other previously observed tidal disruption event.

    Astronomers have spotted a rare and radiant pulse of light—the last gasp of a dying star that has been sucked toward the center of a supermassive black hole and shredded into sinuous strings of stardust. This process is delightfully called spaghettification, but make no mistake: it’s gruesome.

    🌌 You love our badass universe. So do we. Let’s nerd out over it together.

    “When a black hole devours a star, it can launch a powerful blast of material outwards that obstructs our view,” Samantha Oates, an astronomer at the University of Birmingham, said in a statement. “This happens because the energy released as the black hole eats up stellar material propels the star’s debris outwards.”

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    The researchers used the European Southern Observatory’s Very Large Telescope and New Technology Telescope in Chile, the Las Cumbres Observatory global telescope network, and the Neil Gehrel’s Swift Satellite to monitor the flare, which they dubbed AT2019qiz. They tracked AT2019qiz for six months, making observations in optical, ultraviolet, X-ray, and radio, as it brightened and then eventually faded. The scientists published their findings in Monthly Notices of the Royal Astronomical Society.

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    At just 215 million light-years from Earth, AT2019qiz is the closest such flare ever observed. The scientists believe the star at the center of the cataclysmic event was at one point roughly the same mass as our sun. It lost about half its mass once the supermassive black hole, which is around a million times more massive than the star, began slurping it up.

    As the stellar material is pulled from the star, it begins to wrap around the black hole, surrounding it in a curtain of dust. In some cases, the swirling debris can reach speeds of up to 10,000 kilometers per second. When the material is finally devoured by the black hole, it generates a powerful flare observable to Earth’s powerful telescopes.

    The new event could provide scientists with an especially critical view of this incredibly destructive process.

    “This unique ‘peek behind the curtain’ provided the first opportunity to pinpoint the origin of the obscuring material and follow in real time how it engulfs the black hole,” Kate Alexander, a NASA Einstein Fellow at Northwestern University, said in the statement.

    Tidal disruption events like AT2019qiz are extremely rare. Scientists have only observed around 100

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

    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 could actually see the curtain of dust and debris being drawn up as the black hole launched a powerful outflow of material with velocities up to 10,000 km/s (22 million miles per hour),” explained Kate Alexander, a NASA Einstein Fellow at Northwestern University. “This is a unique ‘peek behind the curtain’ that provided the first opportunity to pinpoint the origin of the obscuring material and follow in real time how it engulfs the black hole.”

    A paper on the discovery was published Monday in Monthly Notices of the Royal Astronomical Society. 

    The event is so close and clear that Berger says it will help scientists learn more about the powerful forces at work, particularly the simultaneous pull of the shredded star into the black hole and the outward explosion of material from the star. 

    “Until now, the nature of these emissions has been heavily debated, but here we see that the two regimes are connected through a single process.”

    The hope is that AT2019qiz could be a sort of Rosetta stone for studying and interpreting what black holes have for lunch in the future. One distant day, intergalactic space travelers may even give thanks that this discovery regularly allows them

    Astronomers capture a black hole shredding star into spaghetti strands

    • Astronomers at the European Southern Observatory observed a black hole sucking in a faraway star, shredding it into thin strands of stellar material.
    • This process, known as “spaghettification,” happens because of black holes’ powerful gravitational force.
    • At 215 million light-years away, this spaghettification process is the closest ever observed by astronomers. 
    • Visit Business Insider’s homepage for more stories.

    Astronomers have captured a rarely-seen event: a flare of light caused by a black hole devouring a nearby star like spaghetti.

    Observed in the Eridanus constellation, about 215 million light-years away from Earth, the star’s destruction is the closest such event astronomers have ever observed. 

    “When an unlucky star wanders too close to a supermassive black hole in the center of a galaxy, the extreme gravitational pull of the black hole shreds the star into thin streams of material,” study author Thomas Wevers, a fellow at the European Southern Observatory in Santiago, Chile, said in a press release about the discovery.

    This process is called a tidal disruption event – or, more colloquially, “spaghettification,” a nod to the long, thin strands a star becomes as the black hole’s gravity stretches it thinner and thinner. 

    When these strands get sucked into the black hole, they release a powerful flare of energy that astronomers can detect, even from hundreds of millions of light-years away. 

    spaghettification

    A screenshot taken from a video zooming in on the AT2019qiz tidal disruption event, 215 million light-years away. This phenomenon, a blast of light from a star being ripped apart by a supermassive black hole, has been studied by ESO telescopes.

    N. Risinger/ESO/Digitized Sky Survey 2


    The researchers studied the dying star over a six-month period, using tools including ESO’s Very Large Telescope and its New Technology Telescope, and published their findings in Monthly Notices of the Royal Astronomical Society.

    Examining spaghettification in ‘unprecedented detail’

    The research team discovered the star soon after it started getting ripped apart, and observed it through ultraviolet, optical, X-ray and radio wavelengths. The combination of the star’s proximity and timing allowed the astronomers to study it in “unprecedented detail,” according to the press release.

    Even though a spaghettifying star releases a bright energy flare, researchers have often had trouble in the past examining such flares because dust and debris obscure them. Now they know the debris comes from the spaghettification process itself.

    “We found that, when a black hole devours a star, it can launch a powerful blast of material outwards that obstructs our view,” Samantha Oates, an astronomer at the University of Birmingham and a coauthor of the study, said in the press release.

    In other words, as the black hole gobbles up the star, it releases energy that flings chunks of star-debris outwards. 

    The team also estimated the size of the dying star: It was about the mass of our own Sun, which is 2×1030 kg, or about 330,000 Earths. 

    By the end of the study period, “it lost about half of that to the monster black hole, which is over

    Astronomers witness star being “turned into spaghetti” by black hole

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    Researchers found that when a star is "spaghettified" a blast of material is launched outwards (ESO)
    Researchers found that when a star is “spaghettified” a blast of material is launched outwards (ESO)

    Astronomers have witnessed the final moments of a star being devoured by a supermassive black hole – and it’s not pretty.

    A blast of light from 215 million light years away from Earth allowed astronomers to study the “tidal disruption event” in unprecedented detail. 

    Stars which wander too close to vast supermassive black holes are shredded (“spaghettified”) into thin streams of material, which are in turn devoured, releasing flashes of light. 

    Matt Nicholl, a lecturer and Royal Astronomical Society research fellow at the University of Birmingham, UK said, “The idea of a black hole ‘sucking in’ a nearby star sounds like science fiction. 

    “But this is exactly what happens in a tidal disruption event.”

    Read more: Astronomers find closest black hole to Earth

    Thomas Wevers, an ESO Fellow in Santiago, Chile says, “When an unlucky star wanders too close to a supermassive black hole in the centre of a galaxy, the extreme gravitational pull of the black hole shreds the star into thin streams of material.”

    Although powerful and bright, up to now astronomers have had trouble investigating this burst of light, which is often obscured by a curtain of dust and debris. 

    The researchers say that when a black hole devours a star, it launches a powerful blast of material outwards, that can obstruct our view. 

    The researchers were able to get a clear, unobstructed view, as they caught the event extremely early. 

     “Because we caught it early, we could actually see the curtain of dust and debris being drawn up as the black hole launched a powerful outflow of material with velocities up to 10,000 km/s,” says Kate Alexander, NASA Einstein Fellow at Northwestern University in the US. 

    “This unique ‘peek behind the curtain’ provided the first opportunity to pinpoint the origin of the obscuring material and follow in real time how it engulfs the black hole.”

    Read more: What are fast radio bursts, and why do they look like aliens?

    The team carried out observations of AT 2019qiz, located in a spiral galaxy in the constellation of Eridanus, over a 6-month period as the flare grew in luminosity and then faded away.

     “Several sky surveys discovered emission from the new tidal disruption event very quickly after the star was ripped apart,” says Wevers. 

    “We immediately pointed a suite of ground-based and space telescopes in that direction to see how the light was produced.”

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    Black hole kills star by ‘spaghettification’ as telescopes watch

    Telescopes have captured the rare light flash from a dying star as it was ripped apart by a supermassive black hole

    This rarely seen “tidal disruption event” — which creates spaghettification in stars as they stretch and stretch – is the closest such known event to happen, at only 215 million light-years from Earth. (For comparison, the nearest star system to Earth – Alpha Centauri — is roughly 4 light-years away, and the Milky Way is roughly 200,000 light years in diameter.) One light-year is the distance light travels in a year, about 6 trillion miles (10 trillion kilometers). 

    “The idea of a black hole ‘sucking in’ a nearby star sounds like science fiction. But this is exactly what happens in a tidal disruption event,” the new study’s lead author Matt Nicholl, a lecturer and Royal Astronomical Society research fellow at the University of Birmingham in the United Kingdom, said in a European Southern Observatory statement. Researchers caught the event in action using numerous telescopes, including ESO’s Very Large Telescope and New Technology Telescope.

    Related: The strangest black holes in the universe

    An artist’s illustration of a star’s death by “spaghettification” as it is ripped to shreds by a supermassive black hole. Scientists using the European Southern Observatory’s Very Large Telescope has spotted such an event. (Image credit: ESO/M. Kornmesser)

    “When an unlucky star wanders too close to a supermassive black hole in the center of a galaxy, the extreme gravitational pull of the black hole shreds the star into thin streams of material,” co-author Thomas Wevers said in the same statement. Wevers is an ESO Fellow in Santiago, Chile and was at the Institute of Astronomy at the United Kingdom’s University of Cambridge when he did the work. 

    It has been difficult to see these events in the past because the black hole eating up the star has a tendency to shoot out material from the dying star, such as dust, that obscures the view, ESO officials said.  Luckily, the newly studied event was studied shortly after the star ripped to shreds.

    Related: Black Holes: There’s no escape (infographic)

    Researchers studied the event, known as AT 2019qiz, over six months as the flare became bright and then faded away. Observations took place in ultraviolet, optical, X-ray and radio wavelengths. Looking at the event in this comprehensive way showed how the material leaves the star and the flare  the star sends as its dying gasp, researchers said.

    The team also estimated the size of the doomed star at about the same mass as our own sun. It didn’t have a chance against the black hole, which has a mass of more than 1 million times that of the sun.

    AT 2019qiz also acts as a bellwether for learning about how matter behaves in the extreme environment around supermassive black holes, the team said. A study based on the research was published in the Monthly Notices of the Royal Astronomical Society.

    Follow Elizabeth Howell on Twitter @howellspace. Follow

    We Watched As A Nearby Star Was Sucked In And ‘Spaghettified’ By A Monster Black Hole, Say Scientists

    A star in the act of being devoured by a supermassive black hole. It’s the latest incredible cosmic phenomenon tracked and traced by astronomers using giant telescopes.

    This iconic “tidal disruption event”—named “AT2019qiz”—occurred 215 million light-years away, which makes it the closest observed so far. 

    “The idea of a black hole “sucking in” a nearby star sounds like science fiction, but this is exactly what happens in a tidal disruption event,” said Dr Matt Nicholl, a lecturer and Royal Astronomical Society research fellow at the University of Birmingham in the UK, and lead author of the paper published today in Monthly Notices of the Royal Astronomical Society.

    “We were able to investigate in detail what happens when a star is eaten by such a monster,” he added.

    MORE FROM FORBESStop Looking For An ‘Earth 2.0,’ Say Scientists As They Detect An Even Better ‘Superhabitable’ World

    What is a ‘tidal disruption event?’

    It’s when a star gets too close to a black hole and thus gets pulled apart by the black hole’s extreme gravitational pull. “An unfortunate star in the nucleus of a galaxy can find itself on an orbit that intersects the tidal radius of the central supermassive black hole,” reads the paper. “This destruction can power a very luminous flare.” That’s exactly what the researchers saw.

    What happened to the star?

    It was shredded into a tube of material. The astronomical term used to describe it is “spaghettification.”

    Under the extreme tidal forces of a black hole, stars can be vertically stretched and horizontally compressed into long thin streams of material. “The observations showed that the star had roughly the same mass as our own Sun, and that it lost about half of that to the black hole, which is over a million times more massive,” said Nicholl, who is also a visiting researcher at the University of Edinburgh in the UK.

    MORE FROM FORBESWhat’s That Very Bright Planet In The East? How To See Mars This Week At Its Best Until 2052

    Why is this such a rare sight for astronomers? 

    During the star’s “spaghettification” some of the material fell into the black hole and released a bright flare of energy. Astronomers detected that rare blast of light. It’s a sight described by the researchers as “faint and fast”—such events are usually obscured by a curtain of dust and debris, and it was only because it was detected just after the star was ripped apart that the flare could be detected. 

    “When a black hole devours a star, it

    A mini fractal universe may lie inside charged black holes (if they exist)

    Black holes are perhaps the strangest, least-understood objects in our universe. With so much potential — being linked to everything from wormholes to new baby universes — they have sucked in physicists for decades. 

    But as strange as these known objects are, even stranger types of black holes could be dreamed up. In one upside-down, hypothetical version of the universe, a bizarre type of black hole could exist that is stranger than an M.C. Escher sketch. Now, a team of researchers has plunged into the mathematical heart of so-called charged black holes and found a slew of surprises, including an inferno of space-time and an exotic fractal landscape … and potentially more.

    Related: 9 ideas about black holes that will blow your mind

    Welcome to a holographic superconductor

    There are all sorts of potential, hypothetical black holes: ones with or without electric charge, ones spinning or stationary, ones surrounded by matter or those floating in empty space. Some of these hypothetical black holes are known for certain to exist in our universe; for example, the rotating black hole surrounded by infalling matter is a pretty common presence. We’ve even taken a picture of one.

    But some other kinds of black holes are purely theoretical. Even so, physicists are still interested in exploring them — by diving into their mathematical foundations, we can realize new relationships and implications of our physical theories, which can have real-world consequences. 

    One such theoretical black hole is an electrically charged black hole surrounded by a certain kind of space known as anti-de Sitter. Without getting into too much of the nitty-gritty, this kind of space has constant negative geometric curvature, like a horse saddle, which we know is not a good description of our universe. (A cosmos with anti-de Sitter space, all else being the same, would have a negative cosmological constant, which means that any matter would tend to condense into a black hole, versus the known accelerating expansion that is flinging the universe apart. 

    This horse-saddle space doesn’t exist in our universe, But that’s okay: It turns out that these exotic black holes still have surprisingly intricate structures worth exploring.

    Related: The 18 biggest unsolved mysteries in physics

    One of the reasons it’s worth exploring is that charged black holes share a lot of similarities with rotating black holes, which certainly do exist in our universe, but charged black holes are mathematically simpler to grapple with. So by studying charged black holes we can gain some insights into real-world rotating black holes. 

    Also, physicists have found that when these black holes become relatively cool, they build up a “haze” of quantum fields around their surfaces. This haze sticks to the surface, pulled inward by the never-tiring gravity of the black hole itself, but pushed outward by the electric repulsion of the same black hole. A haze of quantum fields operating in stability on a surface is also known as a superconductor. Superconductors have real-world applications (namely, they can transmit electric current with

    Black hole-sized magnetic fields could be created on Earth, study says

    Scientists should be able to create magnetic fields on Earth that rival the strength of those seen in black holes and neutron stars, a new study suggests. 

    Such strong magnetic fields, which would be created by blasting microtubules with lasers, are important for conducting basic physics, materials science and astronomy research, according to a new research paper authored by Osaka University engineer Masakatsu Murakami and colleagues. The paper was published Oct. 6 in the open-access journal Scientific Reports.

    Most magnetic fields on Earth, even artificial ones, are not particularly strong. The magnetic resonance imaging (MRI) used in hospitals typically produces fields of around 1 tesla, or 10,000 gauss. (For comparison, the geomagnetic field that swings compass needles to the north registers between 0.3 and 0.5 gauss.) Some research MRI machines use fields as high as 10.5 tesla, or 105,000 gauss, and a 2018 lab experiment involving lasers created a field of up to about 1,200 tesla, or just over 1 kilotesla. But no one has successfully gone higher than that. 

    Related: 9 cool facts about magnets

    Now, new simulations suggest that generating a megatesla field — that is, a 1 million tesla field — should be possible. Murakami and his team used computer simulations and modeling to find that shooting ultra-intense laser pulses at hollow tubes just a few microns in diameter could energize the electrons in the tube wall and cause some to leap into the hollow cavity at the center of the tube, imploding the tube. The interactions of these ultra-hot electrons and the vacuum created as the tube implodes leads to the flow of electric current. The flow of electric charges is what creates a magnetic field. In this case, the current flow can amplify a pre-existing magnetic field by two to three orders of magnitude, the researchers found.

    The megatesla magnetic field wouldn’t last long, fading after about 10 nanoseconds. But that’s plenty of time for modern physics experiments, which frequently work with particles and conditions that wink out of existence in far less than the blink of an eye. 

    Murakami and his team further used supercomputer simulations to confirm that these ultra-strong magnetic fields are in reach for modern technology. They calculated that creating these magnetic fields in the real world would require a laser system with a pulse energy of 0.1 to 1 kilojoule and a total power of 10 to 100 petawatts. (A petawatt is a million billion watts.) Ten-petawatt lasers are already being deployed as part of the European Extreme Light Infrastructure, and Chinese scientists are planning to build a 100 petawatt laser called the Station of Extreme Light, Science Magazine reported in 2018.

    Ultrastrong magnetic fields have multiple applications in fundamental physics, including in the search for dark matter. Superstrong magnets can also confine plasma inside nuclear fusion reactors into a smaller area, paving the way for viable fusion energy in the future, Live Science previously reported.

    Originally published on Live Science.

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