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Steven Spielberg Says He “Burst Into Tears” Seeing Michelle Williams, Paul Dano Dressed as His Parents on ‘The Fabelmans’ Set – Yahoo Entertainment
- Steven Spielberg Says He “Burst Into Tears” Seeing Michelle Williams, Paul Dano Dressed as His Parents on ‘The Fabelmans’ Set Yahoo Entertainment
- Steven Spielberg Tells Colbert He ‘Burst Into Tears’ When He First Saw Michelle Williams and Paul TheWrap
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- Steven Spielberg reveals he burst out crying when he saw Paul Dano and Michelle William as parents Daily Mail
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Steven Spielberg Says He “Burst Into Tears” Seeing Michelle Williams, Paul Dano Dressed as His Parents on ‘The Fabelmans’ Set – Yahoo! Voices
- Steven Spielberg Says He “Burst Into Tears” Seeing Michelle Williams, Paul Dano Dressed as His Parents on ‘The Fabelmans’ Set Yahoo! Voices
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Leonid meteor shower 2022 could see burst of fireballs tonight. How to watch.
The 2022 Leonid meteor showers could light up the sky tonight with massive outbreaks of bright fireballs, numbering in the hundreds, according to astronomy experts.
While the expected peak of the Leonids, known as one of the top meteor showers in the fall season because of its bright fireballs, was actually last night, some experts say there could be a bigger burst of shooting stars early Saturday, Nov. 19, this year.
Weather conditions look favorable for viewing in New Jersey, with much of the state expected to have clear or partly cloudy skies after midnight. But it will be very cold.
“While it might not live up to its historical reputation, it could end up being one of the best astronomy events of the year,” AccuWeather said in a preview of the 2022 Leonids.
AccuWeather says two meteor experts from the American Meteor Society have analyzed the timing of when the Earth will move through different trails of space debris from a comet known as 55P/Tempel-Tuttle, and they believe our planet could see the biggest burst of shooting stars early Saturday morning.
If their analysis is correct, AccuWeather says, sky watchers “could see anywhere from 50 to 200 meteors per hour” during a short period on Saturday. They say the main window for that big burst could be between 1 a.m. and 1:30 a.m. Eastern time Saturday.)
Other experts, however, aren’t convinced that the Leonids will put on a spectacular sky show this year. But they say it’s still worth watching late Friday night into early Saturday.
During an average year, the Leonid shower usually generates 10 to 15 meteors per hour in dark areas away from city lights. And some years this shower has had massive outbreaks of bright fireballs, numbering in the hundreds.
The EarthSky astronomy website agrees the Leonid meteor shower sometimes over-performs, with huge numbers of shooting stars. But, “in most years, the Lion whimpers rather than roars.”
Experts say the Leonids will continue to be visible in smaller numbers through Dec. 2 after the peak ends Saturday.
When and where to look
You can see the Leonid meteors from almost anywhere, but experts say you will increase your chances if you go to a park or open area in a rural place, as far away as possible from bright city lights and street lights.
Bring a blanket or a lawn chair for comfort, and bundle up, because temperatures are running far below normal in our region this week. And give your eyes about 20 minutes to adjust to the dark sky when you’re looking up.
Thrillist.com says “the best time to see the Leonids will be after midnight and toward morning local time” on Friday. “The earlier end of that window may be best, though, because the last quarter moon will be rising after midnight, “possibly obscuring your view of fainter meteors.”
As to which part of the sky to look at, Thrillist recommends looking near the constellation Leo, which is the Leonids’ radiant — the area of the sky where the meteors appear to be originating from as they shoot out.
“However, don’t look right at the radiant,” the website says. “The meteors will be moving away from that point. You’ll see more meteors by looking anywhere else in the sky.”
Space.com says the Leonids are among the fastest meteors of any major shower, “zipping through the sky at 44 miles per second.” Rapid speeds like that “tend to produce bright and colorful meteors with hues of white, blue, aquamarine and even green, which leave long-lasting streaks or trains in their wake,” the space website notes.
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Len Melisurgo may be reached at LMelisurgo@njadvancemedia.com.
GRB221009A gamma-ray burst is a once in a century event
All eyes are on the source of the record-breaking gamma-ray burst that lit up the sky last week.
On Oct. 9, a beam of light more energetic than astronomers had ever seen zipped past our planet, temporarily blinding detectors on several NASA satellites. The beam came from a gamma-ray burst, the most energetic type of explosion known to occur in the universe (apart from the Big Bang), which is believed to accompany the birth of some black holes.
Within hours, dozens of telescopes all over the world were pointing in the direction of the burst’s source, confirming that this, indeed, was one for the books. The event, officially named GRB221009A, has since earned the nickname BOAT (“brightest of all time”), and astronomers hope it will help shed light on the mind-boggling physics behind these cataclysmic phenomena.
“It’s a once in a century event, maybe once in 1,000 years,” Brendan O’Connor, an astronomer at the University of Maryland and George Washington University, told Space.com. “We’re just really in awe of this event and feeling very lucky to be able to study it.”
Related: Gamma-ray bursts might be much rarer than we thought, study suggests
Gamma-ray bursts are not rare. About once a day, one flashes briefly at our planet from somewhere in the cosmos. Many more are believed to take place throughout the universe. Some gamma-ray bursts light up for just a fraction of a second, probably triggered by collisions of neutron stars, which are stellar corpses left after supernova explosions of massive stars that have run out of fuel in their cores. Others can last for several minutes, most likely caused when a black hole, just born out of a supernova explosion, swallows up so much of its parent star at once that it has to get rid of some in the form of an extremely powerful jet.
The gamma-ray burst of Oct. 9 stood out even among the long-firing gamma-ray bursts previously observed, its photons bombarding satellite detectors for about 10 minutes. The energy those photons packed was higher than any that had been measured before. At 18 teraelectronvolts, some of the GRB221009A photons outperformed by at least a factor of two the most energetic particles produced by Earth’s most powerful particle generator, the Large Hadron Collider.
The burst’s afterglow, caused by the interaction of gamma-rays with cosmic dust, was out of the ordinary as well, outshining any other seen before despite the fact that GRB221009A emanated from a part of the sky obstructed by the thick band of the Milky Way galaxy. The burst was so powerful that it ionized Earth’s atmosphere and disrupted long wave radio communications.
Astronomers manage to trace the origin of only about 30% of all gamma-ray bursts that skim Earth, said O’Connor, who was part of a team of astronomers who used the Gemini South telescope in Chile to observe the aftermath of GRB221009A on Oct. 14, nearly a week after it first lit up. In the case of GRB221009A, astronomers did find the source: a dust-filled galaxy in the constellation Sagitta, also known as the Arrow. And then came another surprise: The gamma-ray burst occurred much closer to Earth than most others that have been observed before.
“These gamma-ray bursts come from the collapse of massive stars, and these stars have very short lifetimes,” Jillian Rastinejad, an astronomy student at Northwestern University, who took part in the Gemini South measurements, told Space.com. “These stars follow the star formation history of the universe. So where star formation peaks, these long gamma-ray bursts peak, which is at about half the age of the universe. This gamma-ray burst, however, has happened much more recently, much nearer to us.”
Astronomers estimate the source of GRB221009A to lie about 2.4 billion light-years from Earth. Closer gamma-ray bursts have been observed before, but they haven’t been as energetic as GRB221009A, adding to the event’s special status.
“Because this event appears so bright to us, we will be able to study it a lot longer and in a lot better detail,” O’Connor said. “At least 50 telescopes are looking at it right now in all wavelengths, and that will help us maximize the science.”
Although only lasting for a few short minutes at best, gamma-ray bursts trigger effects that can be observed for weeks. Astronomers also look for the supernova explosion that generated the burst, which expels material outward more slowly.
“Our current understanding of these explosions is that you have a massive star and as it implodes, it creates a black hole, which then some of the material from the star falls into,” O’Connor said. “The black hole then spits it out as this jet, which is moving nearly at the speed of light, which is the gamma-ray burst. At the same time, when the star implodes, some of that material rebounds outwards, essentially begins moving away at much slower speeds, but still very fast. And this is the supernova explosion.”
As the gamma-rays of the initial burst interact with material in the surrounding universe, they produce an afterglow, which, Rastinejad said, spans the electromagnetic spectrum but is best observed in X-ray and radio wavelengths. Astronomers are still observing the afterglow of GRB221009A, which was first captured by NASA’s gamma-ray-chasing satellite Swift forming colorful rings around the source in the first hours after the burst.
Telescopes are now beginning to see the first signs of the supernova explosion that gave rise to GRB221009A, Rastinejad said, and expect it to “fully develop” over the next few weeks. Due to the position of the source of the burst in the sky, however, they will not be able to observe the supernova throughout its several-month lifetime.
“It’s starting to go behind the sun. So by around the end of November we’re not going to be able to observe it until February,” Rastinejad said
At that time, O’Connor hopes, NASA’s James Webb Space Telescope and Hubble Space Telescope will join the effort, contributing their optical and infrared observing superpowers to the effort.
“This is a remarkable opportunity to look for how much mass was created [in that event],” Rastinejad said. “But also to understand what are the chemical elements that were created in this event. We still don’t know how some of the heaviest elements in the universe have been created, and we think that we might be able to see such processes in supernova explosions.”
Discovered by accident in the 1960s by U.S. military satellites developed to keep an eye on Soviet nuclear testing (which, too, produces gamma-rays), gamma-ray bursts remained a complete mystery for decades. It was only in the 1990s that astronomers first realized that these powerful flashes of light coming from all corners of the universe might have something to do with collapsing giant stars.
A lot of the current understanding of gamma-ray bursts, however, is still based on theory and computer modeling, rather than observations, and astronomers hope that GRB221009A will help fine-tune those theories. A slew of research papers on all aspects of this carefully observed event is certain to follow in the coming months as astronomers strive to make the best out of this once-in-a-lifetime opportunity.
While the relative proximity of a burst as powerful as GRB221009A is a boon to science, astronomers are not keen to see a gamma-ray burst much closer to Earth. Especially not in our galaxy. Scientists think that a gamma-ray burst aimed at our planet from a distance of some thousands of light-years would destroy the planet’s protective ozone layers and trigger changes in the atmosphere that might lead to an ice age. In fact, one such gamma-ray burst may have triggered one of the five major extinction events in Earth’s history, the Ordovician mass extinction some 440 million years ago.
“Luckily, the jets that cause the gamma-ray bursts are very narrowly beamed,” O’Connor said. “Only a few degrees wide. But if it were to happen in our galaxy and was pointed at us, it would be really dangerous to us. Luckily, the rate of these events that we expect to happen in every galaxy is incredibly low.”
Follow Tereza Pultarova on Twitter @TerezaPultarova. Follow us on Twitter @Spacedotcom and on Facebook.
Bright, powerful burst of gamma rays detected
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Multiple space and ground-based telescopes witnessed one of the brightest explosions in space when it reached Earth on October 9. The burst may be one of the most powerful ever recorded by telescopes.
Gamma-ray bursts, or GRBs, are the most powerful class of explosions in the universe, according to NASA. Scientists have dubbed this one GRB 221009A, and telescopes around the world continue to observe its aftermath.
“The exceptionally long GRB 221009A is the brightest GRB ever recorded and its afterglow is smashing all records at all wavelengths,” said Brendan O’Connor, a doctoral student at the University of Maryland and George Washington University in Washington, DC, in a statement.
“Because this burst is so bright and also nearby, we think this is a once-in-a-century opportunity to address some of the most fundamental questions regarding these explosions, from the formation of black holes to tests of dark matter models.”
Scientists believe the creation of the long, bright pulse occurred when a massive star in the Sagitta constellation — about 2.4 billion light-years away — collapsed into a supernova explosion and became a black hole. The star was likely many times the mass of our sun.
Gamma rays and X-rays rippled through the solar system and set off detectors installed on NASA’s Fermi Gamma-ray Space Telescope, the Neil Gehrels Swift Observatory and the Wind spacecraft, as well as ground-based telescopes like the Gemini South telescope in Chile.
Newborn black holes blast out powerful jets of particles that can move at close to the speed of light, releasing radiation in the form of X-rays and gamma rays. Billions of years after traveling across space, the black hole’s detonation finally reached our corner of the universe last week.
Studying an event like this can reveal more details about the collapse of stars, how matter interacts near the speed of light and what conditions may be like in distant galaxies. Astronomers estimate that such a bright a gamma ray burst may not appear again for decades.
The burst’s source sounds distant, but astronomically speaking it’s relatively close to Earth, which is why it was so bright and lasted for so long. The Fermi telescope detected the burst for more than 10 hours.
O’Connor was the leader of a team using the Gemini South telescope in Chile, operated by the National Science Foundation’s National Optical-Infrared Astronomy Research Laboratory, or NOIRLab, to observe the aftermath on October 14.
“In our research group, we’ve been referring to this burst as the ‘BOAT’, or Brightest Of All Time, because when you look at the thousands of bursts gamma-ray telescopes have been detecting since the 1990s, this one stands apart,” said Jillian Rastinejad, a doctoral student at Northwestern University in Illinois who led a second team using Gemini South.
Astronomers will use their observations to analyze the signatures of any heavy elements released by the star’s collapse.
The luminous burst also provided an opportunity for two devices aboard the International Space Station: the NICER (or Neutron star Interior Composition Explorer) X-ray telescope and Japan’s Monitor of All-sky X-ray Image, or MAXI. Combined, the two devices are called the Orbiting High-energy Monitor Alert Network, or OHMAN.
It was the first time the two devices, installed on the space station in April, were able to work together to detect a gamma-ray burst, and meant the NICER telescope was able to observe GRB 221009A three hours after it was detected.
“Future opportunities could result in response times of a few minutes,” said Zaven Arzoumanian, NICER science lead at Goddard Space Flight Center in Greenbelt, Maryland, in a statement.
It’s the BOAT: Astronomers observe “brightest of all time” gamma-ray burst
Astronomers think the gamma-ray burst GRB 221009A represents the birth of a new black hole formed within the heart of a collapsing star. Credit: NASA/Swift/Cruz deWilde
On the morning of October 9, multiple space-based detectors picked up a powerful gamma-ray burst (GRB) passing through our solar system, sending astronomers around the world scrambling to train their telescopes on that part of the sky to collect vital data on the event and its afterglow. Dubbed GRB 221009A, astronomers say the gamma-ray burst is the most powerful yet recorded and likely could be the “birth cry” of a new black hole. The event was promptly published in the Astronomer’s Telegram, and observations are still ongoing.
“In our research group, we’ve been referring to this burst as the ‘BOAT,’ or Brightest Of All Time, because when you look at the thousands of bursts gamma-ray telescopes have been detecting since the 1990s, this one stands apart,” said Jillian Rastinejad, a graduate student at Northwestern University. Rastinejad led one of two independent teams using the Gemini South telescope in Chile to study the event’s afterglow.
“This burst is much closer than typical GRBs, which is exciting because it allows us to detect many details that otherwise would be too faint to see,” said Roberta Pillera, a graduate student at the Polytechnic University of Bari, Italy, and member of the Fermi Large Area Telescope (LAT) Collaboration. “But it’s also among the most energetic and luminous bursts ever seen regardless of distance, making it doubly exciting.”
Gamma-ray bursts are extremely high-energy explosions in distant galaxies lasting between mere milliseconds to several hours. The first gamma-ray bursts were observed in the late 1960s, thanks to the launching of the Vela satellites by the US. They were meant to detect telltale gamma-ray signatures of nuclear weapons tests in the wake of the 1963 Nuclear Test Ban Treaty with the Soviet Union. The US feared that the Soviets were conducting secret nuclear tests, in violation of the treaty. In July 1967, two of those satellites picked up a flash of gamma radiation that was clearly not the signature of a nuclear weapons test.
Enlarge / Swift’s X-ray Telescope captured the afterglow of GRB 221009A about an hour after it was first detected.
NASA/Swift/A. Beardmore (University of Leicester)
That data was filed away, but later Vela satellites with improved instruments recorded several more gamma-ray bursts. A team at Los Alamos National Laboratory analyzed when each burst was detected by different satellites to estimate the sky position of 16 such bursts. And they determined that the bursts weren’t from Earth or our Solar System, publishing their conclusions in a 1973 paper in Astrophysical Journal.
There are two classes of gamma-ray bursts. Most (70 percent) are long bursts lasting more than two seconds, often with a bright afterglow. These are usually linked to galaxies with rapid star formation. Astronomers think that long bursts are tied to the deaths of massive stars collapsing to form a neutron star or black hole (or, alternatively, a newly formed magnetar). The baby black hole would produce jets of highly energetic particles moving near the speed of light, powerful enough to pierce through the remains of the progenitor star, emitting X-rays and gamma rays.
Those gamma-ray bursts lasting less than two seconds (about 30 percent) are deemed short bursts, usually emitting from regions with very little star formation. Astronomers think these gamma-ray bursts are the result of mergers between two neutron stars, or a neutron star merging with a black hole, comprising a “kilonova.”
That hypothesis was confirmed in 2017, when the LIGO collaboration picked up the gravitational wave signal of two neutron stars merging, accompanied by the powerful gamma-ray bursts associated with a kilonova. Earlier this year, astrophysicists spotted mysterious X-rays they believed could be the very first detection of a kilonova “afterglow” from that same merger. (Alternatively, it could be the first observation of matter falling into the black hole that formed after the merger.)
Record-breaking gamma-ray burst possibly most powerful explosion ever recorded
In the early-morning hours of today, 14 October 2022, astronomers using the Gemini South telescope in Chile operated by NSF’s NOIRLab observed the unprecedented aftermath of one of the most powerful explosions ever recorded, Gamma-Ray Burst GRB221009A. This record-shattering event, which was first detected on 9 October 2022 by orbiting X-ray and gamma-ray telescopes, occurred 2.4 billion light-years from Earth and was likely triggered by a supernova explosion giving birth to a black hole.
A titanic cosmic explosion triggered a burst of activity from astronomers around the world as they raced to study the aftermath from what is one of the nearest and possibly the most-energetic gamma-ray burst (GRB) ever observed. Just-released observations by two independent teams using the Gemini South telescope in Chile—one of the twin telescopes of the International Gemini Observatory operated by NSF’s NOIRLab—targeted the bright, glowing remains of the explosion, which likely heralded a supernova giving birth to a black hole.
The GRB, identified as GRB 221009A, occurred approximately 2.4 billion light-years away in the direction of the constellation Sagitta. It was first detected the morning of 9 October by X-ray and gamma-ray space telescopes, including NASA’s Fermi Gamma-ray Space Telescope, Neil Gehrels Swift Observatory, and the Wind spacecraft.
As word of this detection quickly spread, two teams of astronomers worked closely with staff at the Gemini South to obtain the earliest-possible observations of the afterglow of this historic explosion.
In the early-morning hours of Friday, 14 October, two Rapid Target of Opportunity imaging observations were conducted by two independent teams of observers led by graduate students Brendan O’Connor (University of Maryland/George Washington University) and Jillian Rastinejad (Northwestern University). The observations occurred mere minutes apart. The first observation used the FLAMINGOS-2 instrument, a near-infrared imaging spectrograph. The other observation used the Gemini Multi-Object Spectrograph (GMOS).
The teams now have access to both datasets for their analyses of this energetic and evolving event.
“The exceptionally long GRB 221009A is the brightest GRB ever recorded and its afterglow is smashing all records at all wavelengths,” said O’Connor. “Because this burst is so bright and also nearby, we think this is a once-in-a-century opportunity to address some of the most fundamental questions regarding these explosions, from the formation of black holes to tests of dark matter models.”
Thanks to the fast reaction of observers and staff, combined with the use of Gemini Director’s Discretionary Time and efficient data-reduction software like Gemini’s DRAGONS “FIRE” (Fast Initial Reduction Engine), this image was quickly produced soon after the observations.
“The agility and responsiveness of Gemini’s infrastructure and staff are hallmarks of our observatory and have made our telescopes go-to resources for astronomers studying transient events,” said Gemini Chief Scientist Janice Lee.
Already communications have gone out to fellow astronomers through the NASA Gamma-ray Coordinates Network, the archive of which is now filling up with reports from around the world. Astronomers think it represents the collapse of a star many times the mass of our Sun, which in turn launches an extremely powerful supernova and gives birth to a black hole 2.4 billion light-years from Earth.
“In our research group, we’ve been referring to this burst as the ‘BOAT’, or Brightest Of All Time, because when you look at the thousands of bursts gamma-ray telescopes have been detecting since the 1990s, this one stands apart,” said Rastinejad. “Gemini’s sensitivity and diverse instrument suite will help us to observe GRB221009A’s optical counterparts to much later times than most ground-based telescopes can observe. This will help us understand what made this gamma-ray burst so uniquely bright and energetic.”
When black holes form, they drive powerful jets of particles that are accelerated to nearly the speed of light. These jets then piece through what remains of the progenitor star, emitting X-rays and gamma rays as they stream into space. If these jets are pointed in the general direction of Earth, they are observed as bright flashes of X-rays and gamma rays.
Another gamma-ray burst this bright may not appear for decades or even centuries and the case is still evolving. Of note are other extraordinary reports of disturbances in the Earth’s ionosphere affecting long wave radio transmissions from the energetic radiation from the GRB221009A event. Scientists are also wondering how very-high-energy 18 TeV (tera-electron-volt) photons observed with the Chinese Large High Altitude Air Shower Observatory could defy our standard understanding of physics and survive their 2.4 billion year journey to Earth.
This event, because of its relative proximity to Earth, is also a unique opportunity to better understand the origin of the elements heavier than iron and whether they all come solely from neutron-star mergers or also from collapsing stars that trigger GRBs.
“The Gemini observations will allow us to utilize this nearby event to the fullest and seek out the signatures of heavy elements formed and ejected in the massive star collapse,” said O’Connor.
NASA’s Swift and Fermi missions detect exceptional cosmic blast
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Most powerful gamma-ray burst ever seen spotted by astronomers
Astronomers just detected what may be the most powerful flash of light ever seen.
The so-called gamma-ray burst, the most energetic type of electromagnetic explosion known to exist in the universe, was first spotted by telescopes Sunday (Oct. 9).
Gamma-ray bursts, which were discovered accidentally by U.S. military satellites in the 1960s, are likely produced when giant stars explode at the ends of their lives before collapsing into black holes, or when ultradense stellar remnants known as neutron stars collide. Within seconds, these explosions unleash as much energy as the sun will emit during its entire 10-billion-year lifetime.
The flash detected Sunday was the strongest one ever observed, releasing 18 teraelectronvolts of energy. Scientists are still analyzing the measurements, but if the findings are confirmed, the gamma-ray burst would be the first gamma-ray burst ever found to carry more than 10 teraelectronvolts of energy.
Related: Gamma-ray bursts might be much rarer than we thought, study suggests
At first, the strength of the flash confused astronomers; they thought it must have been produced by a relatively close source. They also initially believed that the energy was coming in X-rays, rather than in gamma-rays. Subsequent analyses of the signal confirmed that it was indeed a gamma-ray burst coming from a source some 2.4 billion light-years away. While not exactly nearby, the gamma-ray burst is still the closest ever seen.
Although this gamma-ray burst was within a safe distance from Earth, a much closer one would be catastrophic to our planet. Such an energetic flash within thousands of light-years from Earth would strip the planet of its protective ozone layer and likely cause mass extinction. In fact, scientists think one of the biggest mass-extinction events in Earth’s history — the Ordovician extinction, which occurred 450 million years ago — may have been triggered by such a blast, according to NASA (opens in new tab).
Although the recently spotted gamma-ray burst, dubbed GRB221009A, appeared 20 times closer to Earth than an average gamma-ray burst, it is still far enough away to cause more excitement than concern.
“This is indeed a very exciting event!” Gemma Anderson, an astronomer at Curtin University in Australia, who studies similar phenomena, told ScienceAlert (opens in new tab). “This event being so nearby but also very energetic means the radio, optical, X-ray and gamma-ray light it produces is extremely bright and therefore easy to observe. We can therefore study this gamma ray burst with lots of big and small telescopes around the world and collect very comprehensive datasets as it first brightens and then fades away.”
Gamma-ray bursts come in two varieties. Short gamma-ray bursts are rarer and last no longer than two seconds. These bursts make up about 30% of all such events and are believed to be caused by collisions of neutron stars. The other type, long gamma-ray bursts, can last up to several minutes and are likely produced by hypernovas, stellar explosions that are 100 times brighter than supernovas, in which supermassive stars die after running out of the hydrogen fuel in their cores.
Astronomers mostly see the afterglow of these explosions that comes from electrons energized by the blast. GRB221009A appears to be a long gamma-ray burst, but astronomers don’t know yet what gave rise to it.
“It is still too early to tell,” Anderson told ScienceAlert. “The light from an underlying supernova will take days to brighten. However, given this gamma-ray burst’s long duration, it may be a very powerful type of supernova.”
Telescopes all over the world (and in Earth’s orbit) are now pointing at the dusty galaxy from which the flash emerged. They will try to observe the light generated by the explosion in as many wavelengths as possible to get the most complete picture of its origin.
“When you are dealing with cosmic explosions that blast out stellar remains at near the speed of light, leaving a black hole behind, you are watching physics occurring in the most extreme environments that are impossible to recreate on Earth,” Anderson told ScienceAlert. “We still don’t fully understand this process. Such a nearby explosion means we can collect very high quality data to study and understand how such explosions occur.”
The observations were first published in the Astronomer’s Telegram (opens in new tab) on Sunday, Oct. 9.
Follow Tereza Pultarova on Twitter @TerezaPultarova. Follow us on Twitter @Spacedotcom and on Facebook.
Scientists Have Detected a ‘Completely Unprecedented’ Burst of Energy in Space
Image: Science Photo Library – MEHAU KULYK via Getty Images
Scientists have spotted an “unprecedented” explosion of energy in space, known as a gamma ray burst (GRB), which appears brighter at some wavelengths than any event of this kind observed so far.
Gamma ray bursts are enormous eruptions fueled by intense cosmic phenomena, such as the deaths of huge stars, and they produce some of the brightest spectacles in the universe. News of this particular burst began rippling across social media following its detection on Sunday by the Fermi Gamma-ray Space Telescope and the Neil Gehrels Swift Observatory, both NASA missions, with some astronomers describing it as “an extraordinary event” and potentially “the brightest GRB ever.”
Phil Evans, an astronomer at the University of Leicester who works on Swift’s X-ray telescope, colorfully described the burst, known as GRB 221009A, as “stupidly really bright” in a tweet on Monday.
In an email to Motherboard, Evans emphasized that the discovery is so fresh that it will take a while to unpack its significance, but he noted that the burst is “clearly the brightest GRB we’ve seen in X-rays, at least at the time after the initial explosion that we’ve observed it.”
“The new GRB 221009A is something around 1,000 times brighter than the typical GRB and a few hundred times brighter than the brightest ones seen before—but this is only true in X-rays,” Evans said. “In gamma-rays it is one of the brightest seen (according to the report from the Fermi telescope team).”
Marcos Santander, an astronomer at the University of Alabama, noted in an email that the Fermi satellite’s Gamma-ray Burst Monitor (GBM) was the first to detect the event, and immediately flagged it as exceptional.
“GBM is the most prolific GRB detector and on average it detects a GRB roughly every day, and it has collected thousands of GRBs in more than 14 years of operation since the launch of Fermi in 2008,” Santander told Motherboard. “Of those thousands, the one on Oct 9th was by far the brightest”—so bright, in fact, that it “blinded the instruments for a bit given how many gamma rays were arriving over a very short time.”
“GRBs are also the most luminous events in the Universe,” he continued. “This one could have an intrinsic brightness of 10^22 times that of the Sun, or around a trillion times the entire energy output of all the stars in the Milky Way combined over that short period that the GRB was on if I have the numbers right.”
The cosmic light show probably marks the energetic death of a massive star and its subsequent transformation into a black hole. It is unparalleled at some wavelengths in part because it took place about two billion light years from Earth. This is objectively a huge distance, but it is relatively close for a GRB.
“Bear in mind of course that this event is very new, and it will take time before we have the full picture, so this is somewhat preliminary,” Evans said. “However…it appears to be a ‘long GRB,’ and these are fairly well understood. What happens is that a very massive, rapidly rotating star, reaches the point where its nuclear reactions can no longer produce enough energy to support the weight of the star. The center of it collapses and forms a new black hole, and this releases lots of energy.”
“This causes some of the material making up the star to be fired out in narrow ‘jets’ from the top and bottom of the star—jets of material moving at nearly the speed of light,” he continued. “If one of these jets is pointed towards the Earth, we see the GRB. So that is what has happened here. Why this one is so bright compared to others is not yet clear” though “part of it is just that it’s nearby.”
Swift, which has been in orbit around Earth since 2004, didn’t spot the initial eruption of GRB 221009A because our planet was blocking that part of the sky. But the observatory’s Burst Alert Telescope (BAT) picked up the brilliant aftermath of the blast nearly an hour later, when its fallout came into view.
“This is completely unprecedented—the explosion itself only lasted about 5 minutes (which is fairly typical for a GRB), but GRB explosions are followed by an ‘afterglow’ that usually fades relatively quickly,” Evans said. “We’ve never before had a GRB where the afterglow was so bright that it triggered BAT.”
The GRB did not appear to be very bright at optical wavelengths, but this could be a result of its location in the sky as well as a lack of immediate observations with optical instruments.
“Because of where this GRB is, we have to look right through the disc of our Galaxy to see it,” Evans said. “That disc absorbs a *lot* of the optical light, so if it had been in a ‘better’ bit of sky it would have been a lot brighter.”
“The other thing is that, as far as I can tell, no-one observed it with an optical telescope until after Swift had detected it, so 55 minutes after the GRB (this is because Fermi does not give very good positions of where a GRB is; Swift does). If people had observed it when it first occurred, I would not personally be surprised if it had broken all optical records… But as they didn’t, we can’t say that it did.”
Given its impressive luminosity and mind-boggling possible origin, Evans and many other scientists will be keeping tabs on the evolution of GRB 221009A as it fades into lower-energy forms of light.
“I think the first step is to piece together all the data collected by all the instruments that observed the burst and start to look at the details of how this event actually happened,” Santander said. “These are in the end the most energetic explosions in the Universe so you want to understand what kind of object could produce such an event, what powered this extreme emission, the types of particles that are accelerated and so on.”
“Not only that, being so distant these GRBs can be used as a probe to study the properties of the intervening space, from the amount of light left over from earlier generations of stars, to studying dust clouds in our galaxy and even tests of fundamental physics,” he added. “There will be many papers written about this burst, the first step is to put together all the information and different observatories provide different perspectives so there will be more information as analyses are performed and published.”
All of this new research will help to explain why the birth of this distant black hole produced such blinding cosmic fireworks, a question that can open a window into the most energetic phenomena in the cosmos.
“The key science here is that we are looking at really extreme physics—very strong gravity, large masses moving at very high velocity while extremely hot—conditions you can never create in a lab, so the only way we can start to understand this is through studying extreme astronomical objects like GRBs,” Evans concluded. “A lot of the open questions are pretty detailed physics (and I don’t claim to understand all of them!), particularly about what goes on inside those jets—how particles are accelerated, interact, radiate energy and so on. And because this event is so bright, it really represents an awesome dataset with which to probe that physics.”