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Remember that amazing “first image” of Sagittarius A* (Sgr A) black hole at the heart of the Milky Way? Well, it may not be completely accurate, according to researchers at the National Astronomical Observatory of Japan (NAOJ). Instead, the accretion disk around Sgr A* may be more elongated, rather than the circular shape we first saw in 2022.

Scientists at NAOJ applied different analysis methods to the data of Sgr A* first taken by the Event Horizon Telescope (EHT) team. The EHT data came from a network of eight ground-based radio telescopes. The original analysis showed a bright ring structure surrounding a dark central region. The re-analysis resulting in a different shape implies something about the motions and distribution of matter in the disk.

In fairness to both teams, radio interferometry data is notoriously complex to analyze. According to NAOJ astronomer Miyoshi Mikato, the rounded appearance may be due to the way the image was constructed. “We hypothesize that the ring image resulted from errors during EHT’s imaging analysis and that part of it was an artifact, rather than the actual astronomical structure,” Miyoshi suggested.

This is the first image of Sgr A*, the supermassive black hole at the center of our galaxy. A reanalysis of EHT data by NAOJ scientists suggests its accretion disk may be more elongated than circular. Credit: EHT Explaining the Black Hole Appearance

So, what does Sgr A* look like in the NAOJ re-analysis? “Our image is slightly elongated in the east-west direction, and the eastern half is brighter than the western half,” said Miyoshi. “We think this appearance means the accretion disk surrounding the black hole is rotating at about 60 percent of the speed of light.”

The accretion disk is filled with superheated material “circling the drain” as it were. It’s funneling into the 4-million-solar-mass black hole. As it cycles through the accretion disk, friction and the action of magnetic fields heat the material. That causes it to glow, mostly in x-rays and visible light as well as giving off radio emissions.

Various factors also influence the shape of the accretion disk, including the spin of the black hole itself. In addition, the accretion rate (that is, how much material falls into the disk), as well as the angular momentum of the material, all affect the shape. The gravitational pull of the black hole also distorts our view of the accretion disk. That sort of “funhouse mirror” distortion makes it incredibly difficult to image. As it turns out, either view of the disk’s actual shape—the original EHT “circular” view or the NAOJ elongated view—could be accurate.

So, Why the Different Views of the Black Hole?

How did the teams come up with two slightly different views of Sgr A* using the same data? “No telescope can capture an astronomical image perfectly,” Miyoshi pointed out. For the EHT observations, it turns out that interferometric data from the widely linked telescopes can have gaps. During data analysis, scientists have to use special techniques to construct a complete image. That’s what the EHT team did, resulting in the “round black hole” image.

Miyoshi’s team published a paper describing their results. In it, they propose that the “ring” structure in the 2022 image released by EHT is an artifact caused by the bumpy point-spread function (PSF) of the EHT data. The PSF describes how an imaging system deals with a point source in the region it’s looking at. It helps give a measure of the amount of blurring that occurs because of imperfections in the optics (or in this case, the gaps in the interferometric data). In other words, it had problems with “filling” in the gaps.

The NAOJ team reanalyzed the data and used a different mapping method to smooth over the gaps in the data. That resulted in an elongated shape for the Sgr A* accretion disk. One-half of the disk is brighter and they suggest it’s due to a Doppler boost as the disk rotates rapidly. They suggest that the newly analyzed data and elongated image shows a portion of the disk that lies a few Schwarzschild radii away from the black hole, rotating extremely fast, and viewed from an angle of 40°-45°.

What’s Next?

This reanalysis should help contribute to a better understanding of what the Sgr A* accretion disk actually looks like. The EHT study of Sgr A* resulting in the 2022 image release was the first detailed attempt to map the region around the black hole. The EHT consortium is working on improvements to produce better and more detailed interferometry images of this and other black holes. Eventually, that should result in more accurate views. Follow-up studies should help fill in any gaps in the observations of the accretion disk. In addition, detailed studies of the near environment around the black hole should give more clues to the black hole hidden inside the disk. I

For More Information

First Picture of Milky Way Black Hole ‘May Not Be Accurate’
An Independent Hybrid Imaging of Sgr A* from the Data in EHT 2017 Observations

The post The Milky Way’s Supermassive Black Hole Photo Might Need a Retake appeared first on Universe Today.

The largest and most ambitious Martian drone yet could carry kilograms of scientific equipment over great distances and set itself down on the Red Planet unassisted

As a megadrought stresses the water supply throughout the Southwest, revolutionary research is answering this problem with a groundbreaking technology that pulls large amounts of water from the air in low humidities.

A new study has revealed that methane gas may be trapped within the icy surface of Saturn's moon Titan, forming a distinct crust up to six miles thick, which warms the underlying ice shell and may also explain Titan's methane-rich atmosphere.

Researchers have developed a groundbreaking new material poised to advance high-sensitivity recyclable sensor technology. The team created a recyclable high-sensitivity sensor based on the dynamic polymer network. This next-generation material is garnering attention for its ability to combine environmental sustainability with high performance.

Researchers have successfully developed an ultra-sensitive pressure sensor for electronic skin modeled after the nervous system in the human brain. This technology is applicable to future devices, including AI-based digital healthcare devices, and is expected to be utilized across various fields, such as transparent displays and wearable devices, due to its transparency and physical flexibility.

Researchers have successfully developed an ultra-sensitive pressure sensor for electronic skin modeled after the nervous system in the human brain. This technology is applicable to future devices, including AI-based digital healthcare devices, and is expected to be utilized across various fields, such as transparent displays and wearable devices, due to its transparency and physical flexibility.

Researchers have significantly improved the performance of kesterite (CZTSSe) thin-film solar cells. They developed a new method for doping silver (Ag) in solar cells to suppress defects that hinder cell performance and promote crystal growth, thereby dramatically increasing efficiency and paving the way for commercialization.

- DGIST, KAIST, and Korea University collaborated to develop a three-dimensional device with reversible heating/cooling based on the thermal radiation phenomenon -- Research published as a cover article in Advanced Materials

Researchers have developed a miniature soft lithium-ion battery that could be used as a defibrillator to control heart rhythm during surgery. The flexible lithium-ion battery is constructed by assembling biocompatible hydrogel droplets. The state-of-the-art device is the smallest soft lithium-ion battery with the highest energy density. The research opens the way to developing tiny bio-integrated devices, with a range of applications in robotics, biology, and medicine.

Researchers have exclusively observed molecules participating in hydrogen bonds in liquid water, measuring electronic and nuclear quantum effects that were previously accessible only via theoretical simulations.

Art and science are sometimes poles apart, but that isn't the case in a new research project. For this work, an interdisciplinary team merged scientific research, technological advancements and artistic exploration to experiment with the production, properties and application of a new kind of ceramic.

A researcher has developed a new technique using light which could revolutionize non-invasive medical diagnostics and optical communication. The research showcases how a type of light called the Orbital Angular Momentum (OAM) can be harnessed to improve imaging and data transmission through skin and other biological tissues.

Climate change-related extreme weather, such as massive flooding and prolonged drought, often result in dangerous outbreaks of diarrheal diseases particularly in less developed countries, where diarrheal diseases is the third leading cause of death among young children. Now a study offers a way to predict the risk of such deadly outbreaks using AI modeling, giving public health systems weeks or even months to prepare and to save lives.

A new study of a city in the Democratic Republic of Congo finds that the necessary process of decarbonization is repeating and recreating colonial inequalities.

The Sverris saga describes how castle invaders “took a dead man and cast him unto the well, and then filled it up with stones”, in what may have been an early act of biological warfare - and now researchers believe they have found the skeleton of the man in question

Yesterday was quiet, as the CSICon meeting consisted largely of workshops. The talks begin in earnest today, and I speak tomorrow morning, followed at 2:45 by a visit to what is recognized as Vegas’s best buffet.   First, some pictures of the Strip.

The view from the conference venue, on the 26th floor of the Horsehoe Casino, where there’s a convention center. Vegas is located in the middle of nowhere, among the parched Nevada mountains you can see in the distance.

Below: The Strip, otherwise known as S. Las Vegas Boulevard. I haven’t yet seen it in its full glory at night, when it’s bedecked with moving lights, fountains, and other things to catch the eye, but the whole street is lined with large casinos that, of course, contain hotels for vacationers and gamblers: I believe these two are Caesar’s Palace and the Bellagio

Oy. Alcohol is everywhere: it seems that every other store is selling beer or margaritas (apparently a local favorite). “Paris” is a casino with replicas of Parisian monuments (see below):

Some of the buildings are replicas of famous structures elsewhere in the world. To wit,  there’s a pretty good-sized Eiffel Tower, as well as Belle Epoque architecture:

And, of course, an Arc de Triomphe:

If an unlucky Martian traveler happened to land in Vegas to survey America, it would immediately depart for home, freaked out and baffled.  In fact, being in this city, which I see as the Gate to Hell, makes me feel my own mortality even more strongly. Thank goodness I have the CSICon conference to repair to.

But I also found a duck-themed donut store. Those are small rubber ducks in the window.

The Big Event of last evening was the award of this year’s Richard Dawkins Prize (for the public promulgation of science), which went to British physicist Brian Cox.

The ceremony began with a video filmed in Oxford of Richard describing Cox’s achievements, not neglecting his musical achievements as  keyboard player for the rock band Dare (they released two albums). Richard showed a clip of Cox at a recent performance with the band D:Ream at the Glastonbury Festival, playing keyboard on the hit “Things Can Only Get Better“.  Neil deGrasse Tyson, who made the formal presentation of the award to Cox, pointed out that the song title meant that, at the time, things were at their absolute rock bottom.

Here’s that Glastonbury video from June of this year. Click on “Watch on YouTube:

Tyson’s introduction was, as expected, lively and hilarious, and he wrote it just yesterday, as I learned from dinner on Wednesday. I wasn’t close enough to see the award (it’s always an appropriate statuette, this time made of glass), but here are a couple of lousy, long-distance iPhone photos of the two of them, with Cox getting the award:

The Presentation:

As usual, the recipient then gives an hour lecture on their work, and Cox chose to talk about black holes. It was an absorbing talk with only a couple of slides. The center of attention was the speaker Cox, delivering a perfect talk without notes and without saying “uh” once. This is a man of eloquence, and one who knows how to speak without notes (humanties professors: please learn at least the latter skill).

Da Nooz:

There may be more nooz later as I slept late (hooray!) and must get coffee and hie myself to the conference.

*First, however, I’ll steal my usual three items from Nellie Bowles’s weekly news summary at The Free Press, called this week “TGIF: The McDonald’s Election” (this refers to Trump’s stunt of serving fries at a drive-through McDonald’s). The TGIF is archived here.

I was going to write about this first one, but I’ll let Nellie do it:

→ We hide study results we don’t like: Researchers behind a long-term study on the impact of puberty blockers in gender-dysphoric teens announced that after almost a decade of collecting enormous data they. . . will not release the findings. The vibes aren’t right to release them. They’re holding them back because the findings so far are not good for the cause, said the lead researcher, Johanna Olson-Kennedy. I’m totally serious. The cause here is expanding the use of puberty blockers. And more broadly, the cause is that gender-dysphoric minors need hormonal and surgical interventions. This is part of a pattern to hide data on transitioning minors from the public.

Olson-Kennedy put it this way, in explaining why she will not release the study results: “I do not want our work to be weaponized.” Weaponized here means: People looking at the science she did and responding to it. All Olson-Kennedy admits is that: “Puberty blockers did not lead to mental health improvements.” But she won’t say more! You can’t see the data yourself. Puberty blockers don’t help, but that’s all I’ll say, and I refuse to explain myself.

If this was a privately funded study, I’d say fine. But it’s not. This study was funded with tax dollars. This study was done through the National Institutes of Health. You cannot take American taxpayer money and then refuse to release results because it’s politically inconvenient. But actually, if no one is going to hold you to account—if, in fact, your decision is celebrated—then I guess you can.

Oh, but this study that showed high levels of satisfaction with puberty blockers? This one was published. Very good. So everyone can keep saying scientific consensus, evidence-based,and research-backed. With this one weird trick, you can say that the opposing voices have no evidence (by quickly killing anything that could be evidence).

→ Facebook censorship: Just for old times’ sake, Facebook is doing some censoring ahead of the election. This time it’s a little harder, yes, but they’re up to the task. So the new rule is: You are not allowed to write about the Biden administration’s inefficiencies. Yes, Facebook will block you for trying. Specifically: You cannot point out that the administration set aside $42 billion in 2021 to set up rural broadband and has so far connected zero people. Nor can you point out that they set aside $7.5 billion for electric vehicle charging stations and have, after two and a half years, built eight charging stations. Post about it and it’ll be blacked out as FALSE INFORMATION. This paragraph you just read is forbidden knowledge.

When Facebook was busted for this—this being blocking negative content about Kamala Harris ahead of the election—Facebook said oops! Whoops! Boop! Heard blasting in Facebook HQ: the old Britney anthem. Old habits die hard. Let’s just hope Ella Emhoff doesn’t have a weird laptop floating around!

This is pretty funny:

→ No, Trump does not work at McDonald’s: Donald J. Trump this week took a break from selling Trump Coins and Trump Bibles to do a campaign stunt at a McDonald’s in Feasterville, Pennsylvania. There, he donned a blue apron and learned fry frying techniques while cameras rolled. He went to the takeout window and handed out burgers to giddy supporters. It was pretty standard retail politics, like when politicians in England pull pints or in France, where I assume they disclose an affair. It’s called appealing to the average voter. No one was confused about what was happening. No one needed to get upset. But watching Trump eke past Kamala in the latest polls in this very tight race, the mainstream media could not let McDonald’s stand. First of all: Did you know the photo shoot was staged and that Trump does not actually work at McDonald’s?

That’s right. You caught them: The campaign planned ahead to have the former president come to a McDonald’s franchise. He didn’t even apply through the online portal to become a member of the crew. And did you know his technique was bad? Horrible. Here’s The New York Times explaining that the former president is not good at making fries: “After Donald Trump served fast food during a campaign stop at a McDonald’s, several actual McDonald’s workers who examined a video of his performance earned mixed reviews from workers and patrons alike.” He also threw salt over his shoulder, which was against health codes. Someone appoint a special prosecutor immediately.

Did you know that doing a campaign stop at a fast-food joint is not like actually working at a fast-food joint? MSNBC needs to make sure. Next we’re going to have a special edition investigating whether the tooth fairy is just your mom.

*The NYT reports, as we all know, that the election polls show it to be a squeaker. But even a NYT/Siena poll shows it to be dead even:

Kamala Harris and Donald J. Trump are locked in a dead heat for the popular vote, 48 percent to 48 percent, the final national poll by The New York Times and Siena College has found, as Ms. Harris struggles for an edge over Mr. Trump with an electorate that seems impossibly and immovably divided.

The result, coming less than two weeks before Election Day, and as millions of Americans have already voted, is not encouraging for Ms. Harris. In recent elections, Democrats have had an edge in the popular vote even when they have lost the Electoral College and thus the White House. They have been looking to Ms. Harris to build a strong national lead as a sign that she would do well in such critical swing states as Michigan, Pennsylvania and Wisconsin.

Ms. Harris and Mr. Trump remain effectively tied even after three of the most tumultuous months in recent American political history. A high-profile debate, two attempts on Mr. Trump’s life, dozens of rallies across seven battlefield states and hundreds of millions spent on advertisements have seemingly done little to change the trajectory of the race.

Ms. Harris’s position, if anything, may have declined among likely voters since the last Times/Siena College poll, taken in early October. At the time, she had a slight lead over Mr. Trump, 49 percent to 46 percent. The change is within the margin of error, but The Times’s national polling average has registered a tightening in polls over the past few weeks as well, suggesting at the very least that this contest has drawn even closer.

While this latest Times/Siena College poll offers a glimpse into national sentiment, the presidential election will be decided in the seven battleground states where Ms. Harris and Mr. Trump have devoted the overwhelming amount of their time and resources. Most polls in those states — Arizona, Georgia, Michigan, Nevada, North Carolina, Pennsylvania, Wisconsin — suggest the contest is equally close.

Here’s a visual depiction of what the article already said:

*Below is a video of pro-Israel Iranian singer and writer Elica Le Bon taking apart Ta -Neheshi Coates’s pig-ignorant diatribe against Israel in his latest book as well as when Coates did an interview with Trevor Noah. Just skip the first 30 and last 30 seconds if you don’t need the commentary.  Le Bon is one of the most eloquent spokespeople Israel, cutting through the forest of lies and misconceptions that surround this conflict.

Elica on the futility of Western policies that favor Hamas (e.g., calls for a cease-fire).  Cenk Uygur has a cameo trying hard to pop an artery.

More later; I need coffee, and they don’t provide in the rooms here. That is a serious issue.

The odds are good that we are not alone in the Universe. We have found thousands of exoplanets so far, and there are likely billions of potentially habitable planets in our galaxy alone. But finding evidence of extraterrestrial life is challenging, and even the most powerful telescopes we currently have may not produce definitive proof. But there are telescopes in the pipeline that may uncover life. It will be decades before they are built and launched, but when they are, which systems should they target first? That’s the question answered in a recent paper.

There are two major projects in the pipeline with the specific goal of searching for life. One is NASA’s Habitable Worlds Observatory (HWO), and the other is the Large Interferometer For Exoplanets (LIFE). Both would use high-resolution spectroscopy to map the chemical composition of exoplanet atmospheres and identify potential biosignatures. But both are in the early design and proposal stages, and it will be at least the 2040s before either are launched. Both also have a downside, in that they will need long observing times to capture detailed spectra. So when they are launched, they won’t be able to look at exoplanets willy-nilly. They will need a specific plan.

This is where this new paper comes in. In it, the team outlines the criteria for prioritizing targets. Drawing from a range of sources, they filter known exoplanet systems into some best-case groups. The first consists of main-sequence stars within 30 parsecs of Earth. But rather than considering all nearby stars, the list only includes stars that are either single stars or wide binaries. The idea is that these are most likely to have planetary systems with stable orbits. The group also excludes red dwarfs, since red dwarfs are likely to produce large flares and x-rays hostile to life.

The second group consists of star systems that are positioned in a region of the sky best suited for observation by LIFE and HWO. For example, if a system is aligned with the orbital plane of Earth, it will be more difficult to study since the Sun will be in the way for part of the year.

The third group consists of the “Golden Targets.” These are systems known to have potentially habitable planets with atmospheres and excellent observing conditions. There are currently about ten systems in this group, but future observations are likely to add more to the list before LIFE and HWO are launched. This group represents the priority targets for these missions.

If you are curious, you can see which systems are in each group at the LIFE Target Star Database.

Reference: Menti, Franziska, et al. “Database of Candidate Targets for the LIFE Mission.” Research Notes of the AAS 8.10 (2024): 267.

The post Here are Some Potentially Habitable World Targets for the Upcoming LIFE Mission appeared first on Universe Today.

Weaving tales of magical fruit and vegetables into your children's stories may encourage them to eat healthy snacks

Meanwhile, in Dobrzyn, Hili is being cool with Szaron:

Szaron: Are we going to the garden? Hili: I don’t know, I had other plans.  

 

Szaron: Idziemy do ogrodu?
Hili: Nie wiem, miałam inne plany.