- The Fargo shooter used a binary trigger. Here’s what to know about the device that’s worrying police The Associated Press
- Fargo shooter who killed a police officer used ‘binary trigger’ device, had stockpile of weapons at home CNN
- North Dakota AG: Fargo shooter searched for ‘crowds’ Associated Press
- Forum Editorial: Fargo mourns a fallen police officer and struggles to understand an incomprehensible tragedy INFORUM
- First responders receiving mental health support following Friday’s deadly shooting KVLY
- View Full Coverage on Google News
Tag Archives: Binary
Fargo shooter who killed a police officer used ‘binary trigger’ device, had stockpile of weapons at home – CNN
- Fargo shooter who killed a police officer used ‘binary trigger’ device, had stockpile of weapons at home CNN
- Man who ambushed Fargo officers likely had bigger and bloodier attack in mind, attorney general says The Associated Press
- Man who ambushed Fargo officers searched online for ‘kill fast’ and for crowded area events, AG says Bismarck Tribune
- Forum Editorial: Fargo mourns a fallen police officer and struggles to understand an incomprehensible tragedy INFORUM
- First responders receiving mental health support following Friday’s deadly shooting KVLY
- View Full Coverage on Google News
These Binary Stars Are So Close Together That Their Year Is Only 20.5 Hours Long : ScienceAlert
A team of astrophysicists has discovered a binary pair of ultra-cool dwarfs so close together that they look like a single star.
They’re remarkable because they only take 20.5 hours to orbit each other, meaning their year is less than one Earth day. They’re also much older than similar systems.
We can’t see ultra-cool dwarf stars with the naked eye, but they’re the most numerous stars in the galaxy. They have such low masses that they only emit infrared light, and we need infrared telescopes to see them.
They’re interesting objects because theory shows stars this close together should exist, but this system is the first time astronomers have observed this extreme proximity.
A team of astronomers presented their findings at the 241st Meeting of the American Astronomical Society in Seattle. Chih-Chun “Dino” Hsu, an astrophysicist at Northwestern University, led the research. The system is named LP 413-53AB.
“It’s exciting to discover such an extreme system,” said Chih-Chun “Dino” Hsu, a Northwestern astrophysicist who led the study. “In principle, we knew these systems should exist, but no such systems had been identified yet.”
Nature’s extremes play an important role in calibrating our theoretical models, and that’s true of low-mass binaries. Prior to this discovery, astronomers knew of only three short-period, ultra-cool binaries.
The research team found the pair in archival data. They were combing through data using an algorithm Hsu wrote that models stars based on their spectral data.
But in those earlier images, the stars just happened to be aligned, so they appeared as a single star. The chances of that happening are high for a tight binary pair like this.
But Hsu and his colleagues thought the data was odd, so they observed the star more closely with the Keck Observatory. The observations showed that the light curve changed so quickly there must be two stars.
Eventually, they realized they had found the closest binary pair ever found.
“When we were making this measurement, we could see things changing over a couple of minutes of observation,” said Professor Adam Burgasser of UC San Diego. Burgasser was Hsu’s advisor while Hsu was a PhD student.
“Most binaries we follow have orbit periods of years. So, you get a measurement every few months. Then, after a while, you can piece together the puzzle. With this system, we could see the spectral lines moving apart in real-time. It’s amazing to see something happen in the universe on a human time scale.”
To emphasize just how close the stars are to each other, Hsu compared them to our own Solar System and another well-known system.
The pair are closer together than Jupiter and one of its Galilean moons, Callisto. It’s also closer than the red dwarf star TRAPPIST-1 is to its closest planet, TRAPPIST-1b.
The stars are much older than the other three similar systems astronomers know of. While those three are relatively young at up to 40 million years old, LP 413-53AB is several billions of years old, like our Sun.
Their age is a clue that the stars didn’t start out this close to one another. The researchers think they could have started out in an even tighter orbit.
“This is remarkable because when they were young, something like 1 million years old, these stars would have been on top of each other,” said Burgasser.
Or the stars may have begun as a pair on wider orbits and then become closer over time.
Another possibility is the stars started out as a triple-star system. Gravitational interactions could’ve simultaneously ejected one star and drawn the remaining two into a tighter orbit.
More observations of the unique system might help answer that.
Astronomers are interested in stars like these because of what they might tell us about habitable worlds. Since ultracool dwarfs are so dim and cool, their habitable zones are tight regions.
That’s the only way they could warm the planets enough to sustain liquid surface water. But in LP 413-53AB’s case, the habitable zone distance is the same as the stellar orbit, eliminating the possibility of habitable exoplanets.
“These ultracool dwarfs are neighbors of our sun,” Hsu said. “To identify potentially habitable hosts, it’s helpful to start with our nearby neighbors. But if close binaries are common among ultracool dwarfs, there may be few habitable worlds to be found.”
Now that astronomers have found one system as tight as this, they want to know if there are more. That’s the only way to understand all these different scenarios.
It’s difficult to even approach any conclusions when you only have one data point.
But astronomers don’t know if they’ve only found one because they’re so rare or because they’re so difficult to spot.
“These systems are rare,” said Chris Theissen, study co-author and a Chancellor’s Postdoctoral Fellow at UC San Diego.
“But we don’t know whether they are rare because they rarely exist or because we just don’t find them. That’s an open-ended question. Now we have one data point that we can start building on. This data had been sitting in the archive for a long time. Dino’s tool will enable us to look for more binaries like this.”
This article was originally published by Universe Today. Read the original article.
The Origins of Binary Black Holes May Be Hidden in Their Spins, Study Suggests : ScienceAlert
In a recent study published in Astronomy and Astrophysical Letters, a team of researchers at the Massachusetts Institute of Technology (MIT) used various computer models to examine 69 confirmed binary black holes to help determine their origin and found their data results changed based on the model’s configurations.
Essentially, the input consistently altered the output, and the researchers wish to better understand both how and why this occurs and what steps can be taken to have more consistent results.
“When you change the model and make it more flexible or make different assumptions, you get a different answer about how black holes formed in the universe,” Sylvia Biscoveanu, an MIT graduate student working in the LIGO Laboratory, and a co-author on the study, said in a statement.
“We show that people need to be careful because we are not yet at the stage with our data where we can believe what the model tells us.”
Like binary stars, binary black holes are two massive objects orbiting each other, with both having the ability to potentially collide – or merge – together, with another shared characteristic being black holes are sometimes born from the collapse of dying massive stars, also known as a supernova.
But how binary black holes originated remains a mystery, as there are two current hypotheses regarding their formation: “field binary evolution” and “dynamical assembly”.
Field binary evolution involves when a pair of binary stars explode, resulting in two black holes in their place, which continue orbiting each other the same as before.
Since they initially orbited each other as binary stars, it is believed their spins and tilts should be aligned, as well.
Scientists also hypothesize that their aligned spins indicate they originated from a galactic disk, given its relatively peaceful environment.
Dynamical assembly involves when two individual black holes, each with their own unique tilt and spin, are eventually brought together by extreme astrophysical processes, to form their own binary black hole system.
It is currently hypothesized that this pairing would likely happen in a dense environment such as a globular cluster, where thousands of stars in close proximity could force two black holes together.
The real question is: What fraction of binary black holes originate from each respective method? Astronomers believe this answer lies in the data, specifically black hole spin measurements.
Using the 69 confirmed binary black holes, astronomers have determined these massive objects could originate from both globular clusters and galactic disks.
The LIGO Laboratory in the United States has worked with its Italian counterpart, Virgo, to ascertain the spins (rotational periods) of the 69 confirmed binary black holes.
“But we wanted to know, do we have enough data to make this distinction?” said Biscoveanu. “And it turns out, things are messy and uncertain, and it’s harder than it looks.”
For the study, the researchers continuously tweaked a series of computer models to ascertain whether their results agreed with each model’s predictions.
One such model was configured to assume only a fraction of binary black holes were produced with aligned spins, where the remainder have random spins. Another model was configured to predict a moderately contrasting spin orientation.
In the end, their findings indicated the results consistently changed in accordance with the tweaked models.
Essentially, results were consistently altered based on the model’s tweaks, meaning more data than the 69 confirmed binary black holes is likely needed to have more consistent results.
“Our paper shows that your result depends entirely on how you model your astrophysics, rather than the data itself,” said Biscoveanu.
“We need more data than we thought, if we want to make a claim that is independent of the astrophysical assumptions we make,” said Salvatore Vitale, who is an associate professor of physics, a member of the Kavli Institute of Astrophysics and Space Research at MIT, and lead author of the study.
But how much more data will the astronomers require? Vitale estimates the LIGO network will be able to detect one new binary black hole every few days, once the network returns to service in early 2023.
“The measurements of the spins we have now are very uncertain,” said Vitale.
“But as we build up a lot of them, we can gain better information. Then we can say, no matter the detail of my model, the data always tells me the same story – a story that we could then believe.”
This article was originally published by Universe Today. Read the original article.
Binary Haze Interactive and Adglobe announce strategy RPG Redemption Reapers for PS4, Switch, and PC
Published by Binary Haze Interactive [8 articles]” href=”https://www.gematsu.com/companies/binary-haze-interactive”>Binary Haze Interactive and developer Adglobe [8 articles]” href=”https://www.gematsu.com/companies/adglobe”>Adglobe have announced Strategy RPG [150 articles]” href=”https://www.gematsu.com/genres/rpg/strategy-rpg”>strategy RPG Redemption Reapers [1 article]” href=”https://www.gematsu.com/games/redemption-reapers”>Redemption Reapers for PS4 [24,361 articles]” href=”https://www.gematsu.com/platforms/playstation/ps4″>PlayStation 4, Switch [12,692 articles]” href=”https://www.gematsu.com/platforms/nintendo/switch”>Switch, and PC [16,526 articles]” href=”https://www.gematsu.com/platforms/pc”>PC (Steam). It will launch in February 2023 with English and Japanese voice-over options, and English, Japanese, French, Italian, German, Spanish, Portuguese, Russian, Chinese (Simplified and Traditional), and Korean language support.
Here is an overview of the game, via Binary Haze Interactive:
Redemption Reapers is being brought to life by industry luminaries, including tactical RPG [14,721 articles]” href=”https://www.gematsu.com/genres/rpg”>RPG veteran Masayuki Horikawa (Fire Emblem series director and scenario / level designer; Kingdom Hearts III [130 articles]” href=”https://www.gematsu.com/games/kingdom-hearts-iii”>Kingdom Hearts III planning), as well as a star-studded voice cast featuring Kyle McCarley ( 13 Sentinels: Aegis Rim [52 articles]” href=”https://www.gematsu.com/games/13-sentinels-aegis-rim”>13 Sentinels: Aegis Rim, NieR: Automata [112 articles]” href=”https://www.gematsu.com/games/nier-automata”>NieR: Automata), Allegra Clark (Apex Legends, Dragon Age: Inquisition), David Lodge ( Persona 5 [148 articles]” href=”https://www.gematsu.com/games/persona-5″>Persona 5, Final Fantasy [44 articles]” href=”https://www.gematsu.com/series/final-fantasy”>Final Fantasy XV), and Lucien Dodge (Fire Emblem: Three Houses, Trails [28 articles]” href=”https://www.gematsu.com/series/trails”>The Legend of Heroes: Trails of Cold Steel series).
Hope fades across the land following the sudden appearance of the ruthless Mort armies. Efficient as they are brutal, the macabre forces descend upon civilizations, leaving destruction in the wake of their nightly raids. As entire nations fall to the Mort onslaught, the Ashen Hawk Brigade, a contingent of mercenaries specializing in surprise tactics, band together to fight back against the invading legions.
Lead the Ashen Hawk Brigade in tactical skirmishes on 3D maps. Employ strategic moves, directing units across the battlefield before issuing commands to attack, defend, or deploy skills during each turn. Overcome seemingly insurmountable odds by mastering sneak attacks for extra damage or powerful combo strikes from multiple Brigade members.
Ensure each Brigade member is fit for the trials ahead by outfitting the party with powerful gear. Turn hard-earned spoils of victory into resources for crafting mighty weapons and armor. Upgrade skills to unlock combat abilities capable of turning a ragtag troop of underdogs into courageous champions.
Carve through the Mort and uncover a gripping, mature story of wartime struggles. Witness powerful moments unfold between members of the Brigade during fully voiced cutscenes (recorded in English and Japanese audio) as fighters learn more about their allies and the world around them. Guide the Ashen Hawk Brigade’s rise from obscurity to folk heroes as members grapple with their dark past as a deadly—and despised—organization dubbed “Faithless Reapers.”
“Following the success of ENDER LILIES, we aimed to approach a new genre ideal for sharing our love of dark fantasy stories,” said Binary Haze Interactive CEO Hiroyuki Kobayashi in a press release. “Redemption Reapers‘ tactical RPG combat and emotional storytelling combine for a memorable experience we cannot wait to share with the world in early 2023.”
Watch the announcement trailer below. View the first screenshots at the gallery.
Announce Trailer
English
Japanese
This Record-Breaking ‘Black Widow’ Pulsar Is The Most Massive Neutron Star Yet
One of the most extreme stars in the Milky Way just got even more wack.
Scientists have measured the mass of a neutron star named PSR J0952-0607, and found that it’s the most massive neutron star discovered yet, clocking in at a whopping 2.35 times the mass of the Sun.
If true, this is very close to the theorized upper mass limit of around 2.3 solar masses for neutron stars, representing an excellent laboratory for studying these ultra-dense stars at what we think is the brink of collapse, in the hope of better understanding the weird quantum state of the matter of which they are made.
“We know roughly how matter behaves at nuclear densities, like in the nucleus of a uranium atom,” said astrophysicist Alex Filippenko of the University of California, Berkeley.
“A neutron star is like one giant nucleus, but when you have one-and-a-half solar masses of this stuff, which is about 500,000 Earth masses of nuclei all clinging together, it’s not at all clear how they will behave.”
Neutron stars are the collapsed cores of massive stars that were between around 8 and 30 times the mass of the Sun, before they went supernova and blew most of their mass off into space.
These cores, tending to be around 1.5 times the mass of the Sun, are among the densest objects in the Universe; the only thing denser is a black hole.
Their mass is packed into a sphere just 20 kilometers (12 miles) or so across; at that density, protons and electrons can combine into neutrons. The only thing keeping this ball of neutrons from collapsing into a black hole is the force it would take for them to occupy the same quantum states, described as degeneracy pressure.
In some ways this means neutron stars behave like massive atomic nuclei. But what happens at this tipping point, where neutrons form exotic structures or blur into a soup of smaller particles, is hard to say.
PSR J0952-0607 was already one of the most interesting neutron stars in the Milky Way. It’s what is known as a pulsar – a neutron star that is spinning very fast, with jets of radiation emitting from the poles. As the star spins, these poles sweep past the observer (us) in the manner of a cosmic lighthouse so that the star appears to pulse.
These stars can be insanely fast, their rotation rate on millisecond scales. PSR J0952-0607 is the second-fastest pulsar in the Milky Way, rotating a mind-blowing 707 times per second. (The fastest is only slightly faster, with a rotation rate of 716 times per second.)
It’s also what is known as a “black widow” pulsar. The star is in a close orbit with a binary companion – so close that its immense gravitational field pulls material from the companion star. This material forms an accretion disk that whirls around and feeds into the neutron star, a bit like water swirling around a drain. Angular momentum from the accretion disk is transferred to the star, causing its spin rate to increase.
A team led by astrophysicist Roger Romani of Stanford University wanted to understand better how PSR J0952-0607 fit into the timeline of this process. The binary companion star is tiny, less than 10 percent of the mass of the Sun. The research team made careful studies of the system and its orbit and used that information to obtain a new, precise measurement for the pulsar.
Their calculations returned a result of 2.35 times the mass of the Sun, give or take 0.17 solar masses. Assuming a standard neutron star starting mass of around 1.4 times the mass of the Sun, that means that PSR J0952-0607 has slurped up to an entire Sun’s worth of matter from its binary companion. This, the team says, is really important information to have about neutron stars.
“This provides some of the strongest constraints on the property of matter at several times the density seen in atomic nuclei. Indeed, many otherwise popular models of dense-matter physics are excluded by this result,” Romani explained.
“A high maximum mass for neutron stars suggests that it is a mixture of nuclei and their dissolved up and down quarks all the way to the core. This excludes many proposed states of matter, especially those with exotic interior composition.”
The binary also shows a mechanism whereby isolated pulsars, without binary companions, can have millisecond rotation rates. J0952-0607’s companion is almost gone; once it’s entirely devoured, the pulsar (if it’s not tipped over the upper mass limit and collapses further into a black hole) will retain its insanely fast rotation speed for quite some time.
And it will be alone, just like those all the other isolated millisecond pulsars.
“As the companion star evolves and starts becoming a red giant, material spills over to the neutron star, and that spins up the neutron star. By spinning up, it now becomes incredibly energized, and a wind of particles starts coming out from the neutron star. That wind then hits the donor star and starts stripping material off, and over time, the donor star’s mass decreases to that of a planet, and if even more time passes, it disappears altogether,” Filippenko said.
“So, that’s how lone millisecond pulsars could be formed. They weren’t all alone to begin with – they had to be in a binary pair – but they gradually evaporated away their companions, and now they’re solitary.”
The research has been published in The Astrophysical Journal Letters.
Made in Abyss: Binary Star Falling into Darkness details ‘Deep in Abyss’ mode
Get the details below.
The Story Begins
The main character joins Belchero Orphanage as a fledgling “Bell” CAVE Interactive [52 articles]” href=”https://www.gematsu.com/companies/cave-interactive”>Cave Raider. For classes and training, the main character joins the three other students, Raul, a boy who’s always full of energy, the quiet and inconspicuous Tiare, and Dorothea, who’s a bit of an airhead, A few months later, the four finally see the day of their first exploration as “Red Whistles,” but there they are already confronted with the harsh reality of the Abyss…
The Game Cycle
In “Deep in Abyss” mode, players will challenge the Abyss as a new Cave Raider. While enjoying an original story advance through the main quests, collect relics, and complete various quests to earn rewards such as money and experience to develop your character. As you accumulate experience, the Cave Raider’s level will increase, and the player will be able to challenge deeper levels of the Abyss.
Prepare for Raiding / The Town of Orth
In the town of Orth, the base for Cave Raiders, prepare to challenge the Abyss by taking on quests and buying the necessities for your raid. As an apprentice “Red Whistle,” you will mainly receive your assignments from Jiruo at Belchero Orphanage, but as your Whistle level increases, the number of assignments you can receive will also increase. The town of Orth has the following facilities.
- Guild HQ – This is the headquarters of the organization that provides work to Cave Raiders. Various quests can be accepted.
- Supply Shop – A store that sells cave raiding essentials. Besides pickaxes, clothes and consumables are sold here.
- Relic Appraisal – A store that appraises and buys relics brought back from The Abyss. Obtain money and experience here.
- Laffi’s Store – A spice store run by Hablog’s wife Laffi. Purchase food and spices here.
Raiding the Abyss
The main objectives within the Abyss are main quests where an original story unfolds, guild quests accepted at the Guild HQ, and the collection of relics. The main character has three attributes: “physical strength”, “fullness”, and “stamina”. Both fullness and stamina are reduced when taking Action [489 articles]” href=”https://www.gematsu.com/genres/action”>action. Stamina recovers automatically, but to recover fullness you’ll need to eat. It is important to eat regularly to maintain fullness, as stamina cannot be restored while fullness is at zero.
—Raiding the Abyss involves avoiding hazards such as ferocious creatures and unstable terrain. When defeated by a large creature, they give a devastating “game-over” performance.
In addition to the three statuses, the player must consider numerous other factors when raiding the Abyss, including the surrounding environment, the health of the main character, the amount of remaining food, the durability of tools, and the weight of supplies. The player must pay attention to these factors and act appropriately, whether deciding to proceed with the raid, return to the surface, and sometimes even what to bring back.
—Carrying too much will greatly reduce speed of movement, and cost the ability to mine or attack.
Returning
After reaching their objective in the Abyss, the Raider must return to the surface. However, the further the Raider descends, the effects of “The Curse of the Abyss,” physical and mental burdens, become more intense as they return to the surface. The Raider may vomit, experience a significant decrease in fullness, or have blood gush from their body resulting in a decrease in fullness and stamina. In addition to “The Curse of the Abyss”, they may be attacked by creatures, the terrain may have changed or features that were present on the way down may not be available on the way back, forcing them to find a different route back.
Made in Abyss: Binary Star Falling into Darkness is due out for PS4 [23,470 articles]” href=”https://www.gematsu.com/platforms/playstation/ps4″>PlayStation 4, Switch [11,790 articles]” href=”https://www.gematsu.com/platforms/nintendo/switch”>Switch, and PC [15,412 articles]” href=”https://www.gematsu.com/platforms/pc”>PC via Steam on September 1 in Japan and September 2 in North America and Europe.
Astronomers Announce Discovery of Supermassive Binary Black Holes
Two supermassive black holes orbit one another in a binary system. They are 10 times closer to each other than the black holes in the only other known supermassive binary black hole system. Credit: Caltech/R. Hurt (IPAC)
A team of researchers from Purdue University and other institutions has discovered a supermassive
The close separation is significant because such systems are expected to merge eventually. That event will release a massive amount of energy in the form of gravitational waves, causing ripples in space in every direction (and oscillations in matter) as the waves pass through.
Finding systems like this is also important for understanding the processes by which galaxies formed and how they ended up with massive black holes at their centers.
Brief summary of methods
Researchers serendipitously discovered the system when they noticed a repeating sinusoidal pattern in its radio brightness emission variations over time, based on data taken after 2008. A subsequent search of historical data revealed that the system also was varying in the same manner in the late 1970s to early 1980s. That type of variation is exactly what researchers would expect if the jetted emission from one black hole is affected by the Doppler effect due to its orbital motion as it swings around the other black hole. Matthew Lister in the College of Science at Purdue University and his team imaged the system from 2002 to 2012, but the team’s radio telescope lacks the resolution to resolve the individual black holes at such a large distance. His imaging data supports the binary black hole scenario and also provides the orientation angle of the jetted outflow, which is a critical component in the paper’s model for the Doppler-induced variations.
Two supermassive black holes are seen orbiting each other in this artist’s loopable animation. The more massive black hole, which is hundreds of millions times the mass of our sun, is shooting out a jet that changes in its apparent brightness as the duo circles each other. Astronomers found evidence for this scenario in a quasar called PKS 2131-021 after analyzing 45-years-worth of radio observations that show the system periodically dimming and brightening. The observed cyclical pattern is thought to be caused by the orbital motion of the jet. Credit: Caltech/R. Hurt (IPAC)
Purdue professor’s expertise
Matthew Lister, professor of physics and astronomy, Purdue University College of Science, specializes his research in the following areas: active galactic nuclei, astrophysical jets and shocks, quasars and BL Lacertae objects, narrow-line Seyfert I galaxies, very long baseline interferometry.
For more on this study:
Reference: “The Unanticipated Phenomenology of the Blazar PKS 2131–021: A Unique Supermassive Black Hole Binary Candidate” by S. O’Neill, S. Kiehlmann, A. C. S. Readhead, M. F. Aller, R. D. Blandford, I. Liodakis, M. L. Lister, P. Mróz, C. P. O’Dea, T. J. Pearson, V. Ravi, M. Vallisneri, K. A. Cleary, M. J. Graham, K. J. B. Grainge, M. W. Hodges, T. Hovatta, A. Lähteenmäki, J. W. Lamb, T. J. W. Lazio, W. Max-Moerbeck, V. Pavlidou, T. A. Prince, R. A. Reeves, M. Tornikoski, P. Vergara de la Parra and J. A. Zensus, 23 February 2022, The Astrophysical Journal Letters.
DOI: 10.3847/2041-8213/ac504b
Funding: Support for the MOJAVE program includes
MIT Astronomers Discover Mysterious “Black Widow” Binary System
Animation depicting a black widow pulsar and its small stellar companion. Credit: NASA’s Goddard Space Flight Center/Cruz deWilde
The system, which may have originated near the center of the
There are about two dozen black widow binaries in the Milky Way that astronomers know of. This newest candidate, named ZTF J1406+1222, has the shortest orbital period of any yet identified, with the pulsar and companion star circling each other every 62 minutes. The system is especially unusual in that it appears to host a third, far-flung star that orbits around the two inner stars every 10,000 years.
This likely triple black widow is raising questions about how such a system could have formed. Based on its observations, the MIT team proposes an origin story: As with most black widow binaries, the triple system likely arose from a dense constellation of old stars known as a globular cluster. This particular cluster may have drifted into the Milky Way’s center, where the gravity of the central 
An illustrated view of a black widow pulsar and its stellar companion. The pulsar’s gamma-ray emissions (magenta) strongly heat the facing side of the star (orange). The pulsar is gradually evaporating its partner. Credit: NASA’s Goddard Space Flight Center/Cruz deWilde
“It’s a complicated birth scenario,” says Kevin Burdge, a Pappalardo Postdoctoral Fellow in MIT’s Department of Physics. “This system has probably been floating around in the Milky Way for longer than the sun has been around.”
Burdge is the author of a study that was published today (May 4, 2022) in the journal Nature that details the team’s discovery. The researchers used a new approach to detect the triple system. While most black widow binaries are found through the gamma and X-ray radiation emitted by the central pulsar, the team used visible light, and specifically the flashing from the binary’s companion star, to detect ZTF J1406+1222.
“This system is really unique as far as black widows go, because we found it with visible light, and because of its wide companion, and the fact it came from the galactic center,” Burdge says. “There’s still a lot we don’t understand about it. But we have a new way of looking for these systems in the sky.”
The study’s co-authors are collaborators from multiple institutions, including the
Day and night
Black widow binaries are powered by pulsars — rapidly spinning neutron stars that are the collapsed cores of massive stars. Pulsars have a dizzying rotational period, spinning around every few milliseconds, and emitting flashes of high-energy gamma and X-rays in the process.
Normally, pulsars spin down and die quickly as they burn off a huge amount of energy. But every so often, a passing star can give a pulsar new life. As a star nears, the pulsar’s gravity pulls material off the star, which provides new energy to spin the pulsar back up. The “recycled” pulsar then starts reradiating energy that further strips the star, and eventually destroys it.
“These systems are called black widows because of how the pulsar sort of consumes the thing that recycled it, just as the spider eats its mate,” Burdge says.
Every black widow binary to date has been detected through gamma and X-ray flashes from the pulsar. In a first, Burdge came upon ZTF J1406+1222 through the optical flashing of the companion star.
It turns out that the companion star’s day side — the side perpetually facing the pulsar — can be many times hotter than its night side, due to the constant high-energy radiation it receives from the pulsar.
“I thought, instead of looking directly for the pulsar, try looking for the star that it’s cooking,” Burdge explains.
He reasoned that if astronomers observed a star whose brightness was changing periodically by a huge amount, it would be a strong signal that it was in a binary with a pulsar.
Star motion
To test this theory, Burdge and his colleagues looked through optical data taken by the Zwicky Transient Facility, an observatory based in California that takes wide-field images of the night sky. The team studied the brightness of stars to see whether any were changing dramatically by a factor of 10 or more, on a timescale of about an hour or less — signs that indicate the presence of a companion star orbiting tightly around a pulsar.
The team was able to pick out the dozen known black widow binaries, validating the new method’s
The team plans to continue observing the new system, as well as apply the optical technique to illuminate more neutron stars and black widows in the sky.
Reference: “A 62-minute orbital period black widow binary in a wide hierarchical triple” by Kevin B. Burdge, Thomas R. Marsh, Jim Fuller, Eric C. Bellm, Ilaria Caiazzo, Deepto Chakrabarty, Michael W. Coughlin, Kishalay De, V. S. Dhillon, Matthew J. Graham, Pablo Rodríguez-Gil, Amruta D. Jaodand, David L. Kaplan, Erin Kara, Albert K. H. Kong, S. R. Kulkarni, Kwan-Lok Li, S. P. Littlefair, Walid A. Majid, Przemek Mróz, Aaron B. Pearlman, E. S. Phinney, Jan van Roestel, Robert A. Simcoe, Igor Andreoni, Andrew J. Drake, Richard G. Dekany, Dmitry A. Duev, Erik C. Kool, Ashish A. Mahabal, Michael S. Medford, Reed Riddle and Thomas A. Prince, 4 May 2022, Nature.
DOI: 10.1038/s41586-022-04551-1
This research was supported, in part, by the National Science Foundation.
Binary star system captured by two MAGIC telescopes
A binary star system, 5,000 light-years from Earth, that explodes in a dramatic nova every 15 years has been seen by a pair of MAGIC telescopes.
RS Ophiuchi (RS Oph) is in the constellation of the Serpent Bearer and is made up of a white dwarf and a red giant that is on the cusp of burning up in a supernova.
Astronomers from the Max Planck Institute in Germany studied the binary pair using the MAGIC telescope, a system of two Imaging Atmospheric Cherenkov telescopes at the Roque de los Muchachos Observatory on La Palma, Canary Islands.
Every 15 yeas a dramatic explosion comes from this binary pair, as the red giant sheds its material, pulled on to the surface of the White Dwarf, a dead star.
A binary star system, 5,000 light-years from Earth, that explodes in a dramatic nova every 15 years has been seen by a pair of MAGIC telescopes
Birthplaces of a nova are systems in which two very different stars live in a parasitic relationship, usually a smaller and a larger star.
In this case a white dwarf, which is a small, burned-out and dense star , where a teaspoon of matter weighs 1 ton, orbits a red giant, an old star that will soon burn up.
The dying giant star feeds the white dwarf with matter shedding its outer hydrogen layer as the gas flows onto the nearby white dwarf. This flow of matter continues, until the white dwarf overeats itself and explodes.
The temperature and pressure in the newly gained stellar shells become too large and are flung away in a gigantic thermonuclear explosion. The dwarf star remains intact and the cycle begins again – until the spectacle repeats itself.
RS Ophiuchi (RS Oph) is in the constellation of the Serpent Bearer and is made up of a white dwarf and a red giant that is on the cusp of burning up in a supernova
It had been speculated that such explosions involve high energies, but the exact details were unclear – especially for this particular nova.
The two MAGIC telescopes recorded gamma rays with the value of 250 gigaelectronvolts (GeV), among the highest energies ever measured in a nova.
In comparison, radiation is a hundred billion times more energetic than visible light.
The team were able to make the observations, of gamma rays, following initial alerts from other instruments measuring at different wavelengths.
The spectacular eruption of the RS Ophiuchi shows that the MAGIC telescopes’ fast response really pays off, the team explained.
‘It takes them no more than 30 seconds to move to a new target,’ said David Green, a scientist at the Max Planck Institute for Physics and one of the authors of the paper.
After the explosion, several shock fronts propagated through the stellar wind from the Red Giant and the interstellar medium surrounding the binary system.
These shock waves work like a giant power plant in which particles are accelerated to near the speed of light.
A combination of measurements taken by Earth-based telescopes, suggest the gamma rays come from energetic protons – nuclei of hydrogen atoms.
‘This also makes nova outbursts a source of cosmic rays,’ explained Green.
‘However, they tend to play the role of local heroes – meaning to only contribute to the cosmic rays in the close neighborhood.’
The big players for cosmic rays are supernova remnants. The shock fronts created from stellar explosions are far more violent compared to novae.
To fully understand the complicated interplay of violent events with the interstellar medium in the Milky Way, more observations like those of RS Ophiuchi will be necessary.
The MAGIC collaboration will continue to look for ‘restless’ objects in our Galaxy and beyond, according to the team.
The findings have been published in the journal Nature Astronomy.