Science

it’s-cutting-calories—not-intermittent-fasting—that-drops-weight,-study-suggests

It’s cutting calories—not intermittent fasting—that drops weight, study suggests

calories, dieting, intermittent fasting, nutrition, Science, time-restricted eating, weight loss / /

Sensational yet obvious —

The study is small and imperfect but offers more data on how time-restricted diets work.

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It’s cutting calories—not intermittent fasting—that drops weight, study suggests

Intermittent fasting, aka time-restricted eating, can help people lose weight—but the reason why may not be complicated hypotheses about changes from fasting metabolism or diurnal circadian rhythms. It may just be because restricting eating time means people eat fewer calories overall.

In a randomized-controlled trial, people who followed a time-restricted diet lost about the same amount of weight as people who ate the same diet without the time restriction, according to a study published Friday in Annals of Internal Medicine.

The finding offers a possible answer to a long-standing question for time-restricted eating (TRE) research, which has been consumed by small feeding studies of 15 people or fewer, with mixed results and imperfect designs.

The new study—led by Nisa Marisa Maruthur, an internal medicine expert at Johns Hopkins—has its own limitations and, like any one study, isn’t the last word on the matter. But “it takes us one step closer to identifying the underlying mechanisms of TRE,” nutrition experts Krista Varady and Vanessa Oddo of the University of Illinois wrote in an editorial accompanying the study. “Using a controlled feeding design, Maruthur and colleagues show that TRE is effective for weight loss, simply because it helps people eat less.”

The study involved 41 people, 21 who followed a time-restricted diet for 12 weeks and 20 who ate a usual eating pattern (UEP). Most of the participants were Black women (93 percent) with obesity and either pre-diabetes or diet-controlled diabetes, limiting the generalizability of the findings. But the study carefully controlled what and when the participants ate; each participant got controlled meals (breakfast, lunch, dinner, and snack) with identical macro- and micro-nutrients. Each participant was assigned a calorie level for their meals based on an established, standardized equation that estimates baseline caloric need. They were told to maintain their current exercise level, which was monitored with a wrist-worn accelerometer.

No magic necessary

In the time-restricted group, people only ate in a 10-hour window between 8 am and 6 pm, with 80 percent of their total daily calories consumed before 1 pm. In the usual eating group, people ate between 8 am and midnight, with 55 percent of their calories eaten after 5 pm for dinner and a night-time snack. In each eating group, participants were given specific windows of a couple of hours in which they should eat each pre-made meal. The participants ate three meals each week at a research site, where dieticians addressed adherence issues, and their eating was carefully monitored with the use of food diaries and urine tests. Approximately 96 percent of people in both groups followed the schedules to within 30 minutes. Diet adherence—eating all their assigned food and not eating outside food—was also high, with 93 percent in the time-restricted group and 95 percent in the usual eating group.

At the end of the 12 weeks, both groups lost about the same amount of weight, an average of around 2.4 kg (5.3 pounds), with no statistically significant difference between the two groups. The researchers also found no differences between the two groups in their glucose homeostasis, waist circumference, blood pressure, or lipid levels.

“Our results indicate that when food intake is matched across groups and calories are held constant, TRE, as operationalized in our study, does not enhance weight loss,” Maruthur and her colleagues concluded. The authors are upfront about the limitations of the study, though, noting that the results could have been different in different groups of people and potentially in shorter time-restricted windows, such as eight hours instead of 10. They called for more research to explore those questions.

Outside experts applauded the study while also adding that it’s not surprising. “The headline finding that TRE does not magically lead to more weight loss sounds sensational but is also obvious,” Adam Collins, a nutrition expert at the University of Surrey, said.

Naveed Sattar, a professor of cardiometabolic medicine at the University of Glasgow, called the study “well done.” It “tells us what we expected—that there is nothing magical about time-restricted eating on weight change other than effects to reduce caloric intake,” he said. “If time-restricted eating helps some people eat less calories than they would otherwise, great.”

The experts Varady and Oddo, meanwhile, see it as a boon for anyone trying to lose weight. “Many patients stop following standard-care diets (such as daily calorie restriction) because they become frustrated with having to monitor food intake vigilantly each day,” they wrote in their commentary. “Thus, TRE can bypass this requirement simply by allowing participants to ‘watch the clock’ instead of monitoring calories while still producing weight loss.” It’s a “simplified” and “accessible” dietary strategy that anyone can follow, including lower-resource populations, the researchers wrote.

It’s cutting calories—not intermittent fasting—that drops weight, study suggests Read More »

io:-new-image-of-a-lake-of-fire,-signs-of-permanent-volcanism

Io: New image of a lake of fire, signs of permanent volcanism

astronomy, Io, juno, Jupiter, planetary science, Science, volcanism / /
Io: New image of a lake of fire, signs of permanent volcanism

Ever since the Voyager mission sent home images of Jupiter’s moon Io spewing material into space, we’ve gradually built up a clearer picture of Io’s volcanic activity. It slowly became clear that Io, which is a bit smaller than Mercury, is the most volcanically active body in the Solar System, with all that activity driven by the gravitational strain caused by Jupiter and its three other giant moons. There is so much volcanism that its surface has been completely remodeled, with no signs of impact craters.

A few more details about its violence came to light this week, with new images being released of the moon’s features, including an island in a lake of lava, taken by the Juno orbiter. At the same time, imaging done using an Earth-based telescope has provided some indications that this volcanism has been reshaping Io from almost the moment it formed.

Fiery, glassy lakes

The Juno orbiter’s mission is primarily focused on studying Jupiter, including the dynamics of its storms and its internal composition. But many of its orbital passes have taken it right past Io, and this week, the Jet Propulsion Laboratory released some of the best images from these flybys. They include a shot of Loki Patera, a lake of lava that has an island within it. Also featured: the impossibly sheer slopes of Io’s Steeple Mountain.

Looking more closely at the lake, the Juno team found that some of the areas within it were incredibly smooth, raising the possibility that obsidian glass had formed on the surface where it had cooled enough to solidify. Given the level of volcanism on Io, this may be more widespread than the Loki Patera.

Volcanic ash would also create a relatively smooth surface, and is likely to be even more common, but it would have significantly different reflective properties.

How long has this been going on?

But we don’t have to send hardware to Jupiter to learn something about Io. A US-based team got time on the Atacama Large Millimeter Array (ALMA) and used it to record emissions from atoms in Io’s sparse atmosphere. By combining the imaging power of lots of smaller telescopes scattered across a plateau, ALMA is able to spot regional differences in the presence of specific elements in Io’s atmosphere, as well as identify different isotopes of those elements.

What can isotopes tell us? Any atoms that reach Io’s upper atmosphere are at risk of being lost to space. And, because of their relative atomic weights, lighter isotopes have a higher probability of being lost. So, it’s possible to compare the present ratio of elements in the atmosphere with the expected ratio, and we can make inferences about the history of loss of lighter isotopes. And, since the material is put into the atmosphere by volcanoes in the first place, that tells us something about the history of volcanism.

The research team focused on two particular elements: sulfur and chlorine. Sulfur has two common non-radioactive isotopes, 32S and 34S, and chlorine, its neighbor on the periodic table, has 35Cl and 37Cl. There are differences in the ratio of these isotopes throughout the bodies of the Solar System, but those differences are generally small. And, because we think we know what sort of material contributed to the formation of Io, we can focus on the ratios found in bodies that have a similar origin.

Chlorine enters the atmosphere from volcanoes primarily in the form of sodium and potassium salts. These have a very short half-life before they’re split up by exposure to light and radiation. The ALMA data indicated both these chemicals were present in localized regions, likely corresponding to active volcanic plumes. The data from the chlorine isotopes were a bit noisy, so were largely used as a sanity check for the ones obtained from sulfur isotopes.

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boeing-says-it-will-cut-sls-workforce-“due-to-external-factors”

Boeing says it will cut SLS workforce “due to external factors”

Science, Space / /

SLS, but smaller —

“Boeing is reviewing and adjusting current staffing levels.”

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The SLS rocket is seen on its launch pad at Kennedy Space Center in August 2022.

Enlarge / The SLS rocket is seen on its launch pad at Kennedy Space Center in August 2022.

Trevor Mahlmann

On Thursday senior Boeing officials leading the Space Launch System program, including David Dutcher and Steve Snell, convened an all-hands meeting for the more than 1,000 employees who work on the rocket.

According to two people familiar with the meeting, the officials announced that there would be a significant number of layoffs and reassignments of people working on the program. They offered a handful of reasons for the cuts, including the fact that timelines for NASA’s Artemis lunar missions that will use the SLS rocket are slipping to the right.

Later on Thursday, in a statement provided to Ars, a Boeing spokesperson confirmed the cuts to Ars: “Due to external factors unrelated to our program performance, Boeing is reviewing and adjusting current staffing levels on the Space Launch System program.”

Better late than never?

For nearly a decade and a half, Boeing has led development of the core stage of the massive SLS rocket that NASA intends to use to launch the Orion spacecraft for its crewed Moon missions.

The contract has been lucrative for Boeing, and subject to considerable criticism over the years for its largesse, as NASA has spent tens of billions of dollars developing a rocket that reuses Space Shuttle main engines and other elements. Also, the rocket was originally supposed to make its debut in late 2016 or 2017, but did not actually fly for the first time until November 2022. And NASA’s Inspector General has characterized Boeing’s management of the SLS rocket program, at times, as “poor.”

However, when the SLS rocket made its debut a year and a half ago, it performed exceptionally well in lofting an uncrewed Orion spacecraft toward the Moon. After that mission NASA declared the rocket to be “operational,” and Boeing moved into production of the vehicle for future missions that will carry astronauts to the Moon.

So in some sense, these cuts were inevitable. Boeing required a lot of resources to design, develop, test, and write software for the rocket. Now that the development phase is over, it is natural that the company would be scaling down development activities for the core stage.

The Boeing statement did not say so, but sources told Ars that the cuts may eventually amount to hundreds of employees. They will be spread across the company’s rocket facilities in Alabama, Louisiana, and Florida, primarily. The cuts will hit both the core stage program as well as the Exploration Upper Stage program, a new upper stage for the rocket that is also beginning to move from development into production.

Waiting on other elements

When Boeing cites “external factors,” it is referring to the slipping timelines for NASA’s Artemis Program. In January officials with the space agency announced approximately one-year delays for both the Artemis II mission, a crewed lunar flyby, to September 2025; and Artemis III, a lunar landing, to September 2026. Neither of these schedules are set in stone, either. Further delays are possible for Artemis II, and likely for Artemis III if NASA sticks to the current mission plans.

Although the SLS rocket will be ready for the current schedule, barring a catastrophe, the other elements are in doubt. For Artemis II, NASA still has not cleared a heat shield issue with the Orion spacecraft. That must be resolved before the mission gets a green light to proceed next year.

The challenges are even greater for Artemis III. For that mission NASA needs to have a lunar lander—which is being provided by SpaceX with its Starship vehicle—in addition to spacesuits for the lunar surface provided by Axiom Space. Both of these elements remain solidly in the development phase.

Additionally, NASA is grappling with budget challenges. For the first time in more than a decade, the agency is facing budget cuts. This week the space agency’s administrator, Bill Nelson, told Congress, “With less money, we have to make some very tough choices.” Among these could be seeking to use future SLS funding to shore up other elements of Artemis.

One of the people familiar with Boeing’s internal meeting on Thursday said the space agency had come to the company earlier this year and said, in effect, that Boeing would receive less funding as SLS development wound down. The company was given the choice to “stretch” the funding it would receive, or pause for a year due to the delays in the Artemis mission. Boeing chose to stretch the funds, and that was a driver of the cuts this week.

It would be easy, but unfair, to blame SpaceX and Axiom for the delays to future Artemis missions. Congress created the SLS rocket with an authorization bill back in 2010, but Boeing actually had been receiving funding for related work dating back to 2007. By contrast, NASA did not start funding work on the Starship lunar lander until late 2021, and the Axiom spacesuits until 2022. In some sense, these developments are as technically demanding as the SLS rocket work, if not more so.

Boeing says it will cut SLS workforce “due to external factors” Read More »

hospital-prices-for-the-same-emergency-care-vary-up-to-16x,-study-finds

Hospital prices for the same emergency care vary up to 16X, study finds

emergency department, emergency medical care, hospitals, JAMA, medical bills, Science, trauma, trauma care / /

Activation fees —

Hospitals’ “trauma activation fees” are unregulated and extremely variable.

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Miami Beach, Fire Rescue ambulance at Mt. Sinai Medical Center hospital. ]

Enlarge / Miami Beach, Fire Rescue ambulance at Mt. Sinai Medical Center hospital. ]

Since 2021, federal law has required hospitals to publicly post their prices, allowing Americans to easily anticipate costs and shop around for affordable care—as they would for any other marketed service or product. But hospitals have mostly failed miserably at complying with the law.

A 2023 KFF analysis on compliance found that the pricing information hospitals provided is “messy, inconsistent, and confusing, making it challenging, if not impossible, for patients or researchers to use them for their intended purpose.” A February 2024 report from the nonprofit organization Patient Rights Advocate found that only 35 percent of 2,000 US hospitals surveyed were in full compliance with the 2021 rule.

But even if hospitals dramatically improved their price transparency, it likely wouldn’t help when patients need emergency trauma care. After an unexpected, major injury, people are sent to the closest hospital and aren’t likely to be shopping around for the best price from the back of an ambulance. If they did, though, they might also need to be treated for shock.

According to a study published Wednesday in JAMA Surgery, hospitals around the country charge wildly different prices for trauma care. Prices for the same care can be up to 16-fold different between hospitals, and cash prices are sometimes significantly cheaper than the negotiated prices that insurance companies pay.

“The findings illustrate substantial, and often irrational, variations” in trauma pricing, according to the study authors—a group of researchers at Johns Hopkins and the University of California, San Francisco. They suggest that “price variations cannot be explained by trauma severity alone.”

For the study, they obtained data on “trauma activation fees” (TAFs) from hospitals across the US. TAFS were created in 2002 to be standardized billing codes that would help recuperate readiness costs for trauma care. Those overhead costs are what hospitals pay to maintain readiness to provide emergency trauma care around the clock, including having operating rooms constantly ready, as well as sufficient staffing, equipment, and supplies, like blood products. TAFS are billed with four codes corresponding to trauma response levels (I through IV), which are based on standardized criterion of injury severity. These fees are in addition to billing for a patient’s actual medical care.

Wide variation

The researchers pulled TAF data from a platform that aggregates hospital-disclosed pricing data called Torquise Health. From there, they obtained 3,093 unique TAF observations across 761 unique hospitals in 49 states. They broke out TAF fees by different types of trauma response levels as well as types of prices: list prices, cash prices often paid by the uninsured, and negotiated prices paid to insurers.

The prices varied dramatically for each trauma level and pricing type. For instance, for the most severe trauma response level (level I), the median TAF list price was $6,607, while the median negotiated price was $3,431, and the median cash price was $2,663. For the list prices, the span between the 10th percentile prices and the 90th percentile prices went from a low of $1,650 up to 11 times more than that: $18,500. Looking across the percentiles for the negotiated prices, costs ranged from $900 to 11,661, 13 times more. And the cash prices ranged from $660 to $8,190, 12 times more.

The largest spread was seen in the cash prices for trauma response level II TAFs. There, the median cash price was $2,630, but the span between the 10th and 90th percentiles was $768 to $12,140, which is 16 times more.

In all the data, cash prices were often lower than the negotiated prices. This is good for uninsured patients who may be offered cash prices, but it’s not great for the insured. “One could argue that insured patients who are already paying insurance premiums should not pay more than cash prices,” the authors wrote.

Overall, the pricing and lack of transparency is a problem that requires intervention, the authors conclude. “The unexpected and pressing nature of trauma means patients are sent to the closest appropriate hospital and unable to compare prices as they do with nonemergency and shoppable medical services,” the authors wrote. Moreover, the people who will suffer the most from these wide-swinging prices are the uninsured and most financially vulnerable patients, they add.

Hospital prices for the same emergency care vary up to 16X, study finds Read More »

renovation-relic:-man-finds-hominin-jawbone-in-parents’-travertine-kitchen-tile

Renovation relic: Man finds hominin jawbone in parents’ travertine kitchen tile

Archaeology, fossils, geology, Hominin, human fossils, Science / /

Kitchen reno surprise —

Yes, travertine often has embedded fossils. But not usually hominin ones.

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closeup of fossilized jawbone in a piece of travertine tile

Enlarge / Reddit user Kidipadeli75 spotted a fossilized hominin jawbone in his parents’ new travertine kitchen tile.

Reddit user Kidipadeli75

Ah, Reddit! It’s a constant source of amazing stories that sound too good to be true… and yet! The latest example comes to us from a user named Kidipadeli75, a dentist who visited his parents after the latter’s kitchen renovation and noticed what appeared to be a human-like jawbone embedded in the new travertine tile. Naturally, he posted a photograph to Reddit seeking advice and input. And Reddit was happy to oblige.

User MAJOR_Blarg, for instance, is a dentist “with forensic odontology training” and offered the following:

While all old-world monkeys, apes, and hominids share the same dental formula, 2-1-2-3, and the individual molars and premolars can look similar, the specific spacing in the mandible itself is very specifically and characteristically human, or at least related and very recent hominid relative/ancestor. Most likely human given the success of the proliferation of H.s. and the (relatively) rapid formation of travertine.

Against modern Homo sapiens, which may not be entirely relevant, the morphology of the mandible is likely not northern European, but more similar to African, middle Eastern, mainland Asian.

Another user, deamatrona, who claims to hold an anthropology degree, also thought the dentition looked Asiatic, “which could be a significant find.” The thread also drew the attention of John Hawks, an anthropologist at the University of Wisconsin–Madison and longtime science blogger who provided some valuable context on his own website. (Hawks has been involved with the team that discovered Homo naledi at the Rising Star cave system in 2013.)

For instance, much of the appeal of natural stone like travertine for home decor is its imperfections. But who knew that it’s actually quite common to find embedded fossils? It’s rarer to find hominin fossils but not unprecedented. Hawks specifically mentioned a quarry site near Bilzingsleben, Germany, where an archaeologist named Dietrich Mania discovered parts of two humans skulls and a mandible dating as far back as 470,000 years. And a hominin cranium was found in 2002 in a travertine quarry in southwestern Turkey. It was later dated to between 1.2 million and 1.6 million years old.

The obvious question—asked by numerous Redditors— is how one could possibly install all that kitchen tile without noticing a fossilized human jawbone in the travertine. Hawks offered a reasonable answer:

Quarries rough-cut travertine and other decorative stone into large panels, doing basic quality checks for gaps and large defects on the rough stone before polishing. Small defects and inclusions are the reason why people want travertine in the first place, so they don’t merit special attention. Consumers who buy travertine usually browse samples in a showroom to choose the type of rock, and they don’t see the actual panels or tile until installation. Tile or panels that are polished by machine and stacked in a workshop or factory for shipping are handled pretty quickly.

What this means is that there may be lots more hominin bones in people’s floors and showers.

Most will be hard to recognize. Random cross-sections of hominin bones are tough to make out from other kinds of fossils without a lot of training. Noticing a fossil is not so hard, but I have to say that I’ve often been surprised at what the rest of a fossil looks like after skilled preparators painstakingly extract it from the surrounding rock. The ways that either nature or a masonry saw may slice a fossil don’t correspond to an anatomy book, and a cross-section through part of a bone doesn’t usually resemble an X-ray image of a whole bone.

Cue a horde of amateur fossil enthusiasts excitedly scouring their travertine for signs of important archaeological finds.

But as Hawks notes, chances are that one wouldn’t be able to clearly identify a fossil even if it was embedded in one’s tile, given how thin such tiles and panels are typically cut. And one is far more likely to find fossils of algae, plants, mollusks, crustaceans, or similar smaller creatures than human remains. “Believe me, anthropologists don’t want to hear about every blob of bone in your tile,” Hawks wrote. “But certainly somebody has more pieces of the mandible of the Reddit post.”

Kidipadeli75 posted an update to the Reddit thread providing a few more details, such as that he and his parents live in Europe. He’s also pretty sure the mandible doesn’t belong to Jimmy Hoffa. While Kidipadeli75 originally thought the quarry of origin was in Spain, it is actually located in Turkey—just like the hominin cranium found near Kocabaş in 2002. The story is still developing, given that several researchers have already contacted Kidipadeli75 for more information and to offer their expertise. The bone might turn out to be very old indeed and potentially a scientifically significant find.

Could a new HGTV series be far behind? Renovation Relics, perhaps, or Fossil Fixer-Upper.  Feel free to pitch your own show ideas in the comments.

Renovation relic: Man finds hominin jawbone in parents’ travertine kitchen tile Read More »

spacex-and-northrop-are-working-on-a-constellation-of-spy-satellites

SpaceX and Northrop are working on a constellation of spy satellites

Northrop Grumman, Science, Space, spacex / /

X marks the spot —

First launch of these operational vehicles may occur next month from California.

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A Falcon 9 rocket launches a Starlink mission in January 2020.

Enlarge / A Falcon 9 rocket launches a Starlink mission in January 2020.

SpaceX

SpaceX is reportedly working with at least one major US defense contractor, Northrop Grumman, on a constellation of spy satellites for the National Reconnaissance Office.

According to Reuters, development of the network of hundreds of spy satellites by SpaceX is being coordinated with multiple contractors to avoid putting too much control of a highly sensitive intelligence program in the hands of one company.

“It is in the government’s interest to not be totally invested in one company run by one person,” one of the news agency’s sources said, most likely referring to SpaceX founder Elon Musk.

Northrop will provide sensors for a subset of the satellites in the constellation—at least 50 of them—and test those spacecraft at its own facility prior to their launch into orbit, Reuters reports.

A proliferated constellation

The news agency first disclosed the existence of SpaceX’s contract with the National Reconnaissance Office, which is responsible for operating US spy satellites, in March. The network is being built by SpaceX’s Starshield business unit under a $1.8 billion contract signed in 2021.

While this network will be separate from SpaceX’s Starlink Internet constellation, the National Reconnaissance Office contract is leveraging SpaceX’s capability to put a large number of Starlink satellites into orbit with its existing manufacturing facilities and the reusable Falcon 9 rocket. The current Starlink megaconstellation has more than 5,700 operational satellites.

This spysat constellation is considered to be “proliferated” because there will be swarms of satellites launched into low-Earth orbit to provide imaging and other capabilities, and these should be less vulnerable to enemy attack because of their large numbers.

Although no nation has ever attacked another nation’s satellites, major space powers, including the United States, Russia, and China, are clearly working on such measures. A good reference for these efforts is the Secure World Foundation’s annual Global Counterspace Capabilities report.

In its reporting, Reuters suggests that the high-quality imaging sensors on the SpaceX satellites in low-Earth orbit will exceed the resolution of some of the best US spy satellites at higher altitudes. They may also provide a superior alternative to the current use of drones and reconnaissance aircraft, which can be risky to fly in the airspace of other nations.

The first elements of this proliferated constellation are likely to launch next month from Vandenberg Space Force Base on the NROL-146 mission. According to Troy Meink, the National Reconnaissance Office’s principal deputy director, this will be the first of as many as six such launches in 2024.

“This launch will be the first launch of an actual operational system,” Meink said at the annual Space Symposium earlier this month. “This system will increase timeliness of access, diversity of communication paths and enhance our resilience.”

An uneasy partnership

Typically, in its 22 years of operation, SpaceX has eschewed deep partnerships with traditional aerospace contractors, including Northrop Grumman. Early on, in fact, SpaceX had a legal confrontation with Northrop over the pintle engine injector technology used in the Merlin rocket engine that powered the Falcon 1, and later Falcon 9 rocket. SpaceX counter-sued, saying Northrop had abused its position in an advisory role in the Air Force to spy on SpaceX. Eventually, the lawsuits were both dropped with no damages.

More than a decade later, SpaceX launched the “Zuma” satellite, an ultra-expensive classified spacecraft valued in excess of $3 billion and built by Northrop for the National Reconnaissance Office. The launch on a Falcon 9 rocket was successful in January 2018, but the spacecraft was subsequently lost. The failure was later blamed on a payload adaptor supplied by Northrop Grumman, although this has never been publicly confirmed.

It is clearly hoped by US government officials that this collaboration between SpaceX and Northrop will meet a happier fate.

SpaceX and Northrop are working on a constellation of spy satellites Read More »

life-threatening-rat-pee-infections-reach-record-levels-in-nyc

Life-threatening rat pee infections reach record levels in NYC

health, Science / /

Epeedemic —

Between 2001 and 2020, there was an average of 3 cases per year. Last year’s tally was 24.

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A rat looks for food while on a subway platform at the Columbus Circle - 59th Street station on May 8, 2023, in New York City.

Enlarge / A rat looks for food while on a subway platform at the Columbus Circle – 59th Street station on May 8, 2023, in New York City.

A life-threatening bacterial infection typically spread through rat urine sickened a record number of people in New York City last year—and this year looks on track for another all-time high, the NYC Department of Health and Mental Hygiene reports.

The infection is leptospirosis, which can cause a range of symptoms, including non-specific ones like fever, headache, chills, muscle aches, vomiting, diarrhea, and cough. But, if left untreated, can become severe, causing kidney failure, liver damage, jaundice, hemorrhage, bloody eyes (conjunctival suffusion), respiratory distress, and potentially death.

The bacteria that causes it—spirochete bacteria of the genus Leptospira—infect rats, which shed the bacteria in their urine. The germs jump to people through direct contact with open wounds or mucous membranes.

New York City has long been in a (mostly losing) war with its rat population, which last year was estimated to be as many as 3 million. Mayor Eric Adams has made fighting the rat population a key initiative, and just last week, the city council proposed the latest strategy to curtail the furry brown rodent’s colony: birth control in the form of salty pellets.

Still, leptospirosis has not been a prime concern from the rats’ mischief until recently. Between 2001 and 2020, the city logged an average of just three leptospirosis cases a year—and some of those were travel related. But, things took a turn during the pandemic when the rat population seemed to boom. From 2021 and 2022, the average shot up to 15. In 2023, there were 24 cases, the highest number of cases ever recorded for a single year. And as of April 10, there have been six cases so far.

That number of cases so far this year is concerning given that Leptospira bacteria are “fragile,” as the NYC health department puts it. They die quickly in the freezing temperatures of winte and the dry heat of summer. Their main time to thrive is in warm, moist conditions. Last year, the months with the most cases were June and October. The health department noted that climate change, which is causing excessive rain and unseasonably warm temperatures, may be partly driving the uptick in cases.

In a health advisory released last week, the city’s health department advised clinicians to be on the lookout for cases, which are treated with common oral antibiotics when mild or intravenous doses when severe. Symptoms typically develop in 5 to 14 days after an exposure, but can show up anywhere from 2 to 30 days.

Of the 98 locally acquired cases that the city has recorded between 2001 and 2023, nearly all were in men (94 percent) and the median age was 50, with a range of 20 to 80 years. Most often, the cases occurred in the Bronx (37), followed by Manhattan (28), Brooklyn (19), Queens (10), and Staten Island (4). Cases presented to clinicians with acute kidney and liver failure and occasionally severe respiratory involvement. Of the 98 cases, six died.

The cases are typically related to living or working environments with rat urine, contaminated soil and water, or materials frequently contaminated with rat urine, such as trash bags or food waste bins. The health department noted that human-to-human transmission is rare.

New York isn’t the only city plagued by leptospirosis cases. Last year, doctors in the Netherlands reported the case of an 18-year-old with jaundiced, bloody eyes, who had developed leptospirosis after falling into a canal that was likely contaminated with rodent urine.

Life-threatening rat pee infections reach record levels in NYC Read More »

bodies-found-in-neolithic-pit-were-likely-victims-of-ritualistic-murder

Bodies found in Neolithic pit were likely victims of ritualistic murder

anthropology, Archaeology, cultural evolution, forensic archaeology, neolithic, ritual sacrifice, Science, Uncategorized / /

murder most foul —

One victim may have been hogtied alive in pit, à la Mafia-style ligature strangulation.

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View taken from the upper part of the 255 storage pit showing the three skeletons, with one individual in a central position

Enlarge / Three female skeletons found in a Neolithic storage pit in France show signs of ritualistic human sacrifice.

. Beeching/Ludes et al., 2024

Archaeologists have discovered the remains of two women in a Neolithic tomb in France, with the positioning of the bodies suggesting they may have been ritualistically murdered by asphyxia or self-strangulation, according to a recent paper published in the journal Science Advances.

(WARNING: graphic descriptions below.)

France’s Rhône Valley is home to several archaeological sites dating to the end of the Middle Neolithic period (between 4250 and 3600/3500 BCE in the region); the sites include various storage silos, broken grindstones, imported ceramics, animal remains (both from communal meals and sacrifices), and human remains deposited in sepulchral pits. Saint-Paul-Trois-Châteaux is one such site.

According to Bertrand Ludes of the Université Paris Cité and his co-authors, the remains of the three women were found in Pit 69, a structure aligned with the summer and winter solstices, as was often the case in ancient agrarian societies. But the body positioning was decidedly atypical. One woman (No. 1), around age 50, was in the center of the pit, reclining on her side with a vase near her head. The other two bodies were just beneath an overhang. Woman No. 2 was on her back, legs bent, with a piece of grindstone placed on her skull. Woman No. 3 was in a prone position, knees bent, with her neck on the thorax of Woman No. 2 and two chunks of grindstone placed on her back.

The unusual positions imply a forceful, deliberate placement, according to the authors, suggesting they died in the pit rather than being tossed in after death. As for the cause of death, the archaeological evidence combined with recent forensic studies suggests “homicidal ligature strangulation” and “forced positional asphyxia”—at least for two of the three women. Woman No. 2, for example, would have struggled to breathe on her back, especially with the weight of Woman No. 3 pressing down on her neck (positional asphyxia), further exacerbated by the placement of the grindstone fragment.

Saint-Paul-Trois-Châteaux and the area surrounding pits 69 and 70.

Enlarge / Saint-Paul-Trois-Châteaux and the area surrounding pits 69 and 70.

Ludes et al., Sci. Adv. 10, eadl3374 (2024)

Woman No. 3’s prone position would mean she also would have struggled to breathe, and the volume of blood pumped by the heart would have sharply decreased, leading to cardiac arrest, a form of positional asphyxia now known as “prone restraint cardiac arrest.” All these clinical terms don’t quite capture the horrifically cruel nature of the manner of death. Given the placement of the woman’s knees—bent at more than a 90-degree angle, making the legs almost vertical—it’s possible she was tied up lying on her stomach, with the ligature connecting her ankles to her neck (similar to being hog-tied). In this position, “self-strangulation becomes inevitable,” the authors wrote, particularly if the mouth and nose are obstructed or there is cervical compression—say, from the strategic placement of grindstone fragments.

This form of torture, known as incaprettamento, has been used by the Italian Mafia, per Ludes et al., often to punish traitors, and dates as far back as the Italian Mesolithic era, “suggesting a highly ancient origin within ceremonial sites.” Sometimes, the victim would be strangled and the body tied up postmortem before the remains were disposed of. Ludes et al. believe Woman No. 3 would probably have been placed in the burial pit and tied up while still alive before self-strangling to death.

  • Reconstruction of the remains, blocked under the overhang of the wall of the storage pit lined with straw.

    Ludes et al., Sci. Adv. 10, eadl3374 (2024)

  • Reconstruction of skeletal remains for Woman No. 2 positioned on her back with bent knees.

    Ludes et al., Sci. Adv. 10, eadl3374 (2024)

  • Reconstruction of skeletal remains for Woman No. 3 in a prone position on her stomach with bent knees. The feet are behind the pelvis/toward the lower back, and the hands are tied behind the back.

    Ludes et al., Sci. Adv. 10, eadl3374 (2024)

  • Mesolithic rock art scene from the Addaura Cave is believed to depict ritual sacrifice by ligature strangulation (bolded figure).

    B. Ludes et al., 2024

In fact, one scene from Mesolithic rock art found in the Addaura Cave in Sicily, Italy, seems to depict a ritual sacrifice by ligature strangulation. There are 11 human figures and the figure of a slain deer. Nine of the human figures form a circle, within which are the other two human figures (male, judging by the erect genitalia). Those figures are shown lying on their stomachs in a prone position, legs folded beneath them, with a rope stretched between their ankles and necks. The erect male genitalia, and one figure drawn with his tongue hanging out, are both signs of strangulation or hanging, per the authors.

It is notoriously difficult to distinguish between a merely violent death and one with ritualistic overtones when it comes to prehistoric remains. So Ludes et al. combed through existing literature for reports of similar cases. They found 20 cases of probable ligature strangulation or positional asphyxia in total across 14 different archaeological sites in Eastern Europe and Catalonia, spanning nearly 2,000 years. The individuals were found lying on their backs or sides, lower limbs flexed until the feet aligned with the pelvis, indicating hip extension. The oldest remains were found at sites in the Czech Republic and date back to between 5400 and 4800 BCE; the three women found at Saint-Paul-Trois-Châteaux are the most recent.

The latter site in particular has elements that “suggest a profound interconnection between religious systems and power structure in an agricultural society,” the authors concluded—namely, various structures aligned with summer and winter solstices indicative of an agricultural cycle and the placement of two women facing the central woman. It’s unclear why the women were sacrificed, the authors added, but such ritualistic sacrifice likely developed across central and southern Europe sometime in the Mesolithic and evolved over the course of two millennia before culminating in the late Middle Neolithic.

Science Advances, 2024. DOI: 10.1126/sciadv.adl3374  (About DOIs).

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Climate damages by 2050 will be 6 times the cost of limiting warming to 2°

adaptation, climate change, Earth science, Economics, green, mitigation, Science, Sustainability / /
A worker walks between long rows of solar panels.

Almost from the start, arguments about mitigating climate change have included an element of cost-benefit analysis: Would it cost more to move the world off fossil fuels than it would to simply try to adapt to a changing world? A strong consensus has built that the answer to the question is a clear no, capped off by a Nobel in Economics given to one of the people whose work was key to building that consensus.

While most academics may have considered the argument put to rest, it has enjoyed an extended life in the political sphere. Large unknowns remain about both the costs and benefits, which depend in part on the remaining uncertainties in climate science and in part on the assumptions baked into economic models.

In Wednesday’s edition of Nature, a small team of researchers analyzed how local economies have responded to the last 40 years of warming and projected those effects forward to 2050. They find that we’re already committed to warming that will see the growth of the global economy undercut by 20 percent. That places the cost of even a limited period of climate change at roughly six times the estimated price of putting the world on a path to limit the warming to 2° C.

Linking economics and climate

Many economic studies of climate change involve assumptions about the value of spending today to avoid the costs of a warmer climate in the future, as well as the details of those costs. But the people behind the new work, Maximilian Kotz, Anders Levermann, and Leonie Wenz decided to take an empirical approach. They obtained data about the economic performance of over 1,600 individual regions around the globe, going back 40 years. They then attempted to look for connections between that performance and climate events.

Previous research already identified a number of climate measures—average temperatures, daily temperature variability, total annual precipitation, the annual number of wet days, and extreme daily rainfall—that have all been linked to economic impacts. Some of these effects, like extreme rainfall, are likely to have immediate effects. Others on this list, like temperature variability, are likely to have a gradual impact that is only felt over time.

The researchers tested each factor for lagging effects, meaning an economic impact sometime after their onset. These suggested that temperature factors could have a lagging impact up to eight years after they changed, while precipitation changes were typically felt within four years of climate-driven changes. While this relationship might be in error for some of the economic changes in some regions, the inclusion of so many regions and a long time period should help limit the impact of those spurious correlations.

With the climate/economic relationship worked out, the researchers obtained climate projections from the Coupled Model Intercomparison Project (CMIP) project. With that in hand, they could look at future climates and estimate their economic costs.

Obviously, there are limits to how far into the future this process will work. The uncertainties of the climate models grow with time; the future economy starts looking a lot less like the present, and things like temperature extremes start to reach levels where past economic behavior no longer applies.

To deal with that, Kotz, Levermann, and Wenz performed a random sampling to determine the uncertainty in the system they developed. They look for the point where the uncertainties from the two most extreme emissions scenarios overlap. That occurs in 2049; after that, we can’t expect the past economic impacts of climate to apply.

Kotz, Levermann, and Wenz suggest that this is an indication of warming we’re already committed to, in part because the effect of past emissions hasn’t been felt in its entirety and partly because the global economy is a boat that turns slowly, so it will take time to implement significant changes in emissions. “Such a focus on the near term limits the large uncertainties about diverging future emission trajectories, the resulting long-term climate response and the validity of applying historically observed climate–economic relations over long timescales during which socio-technical conditions may change considerably,” they argue.

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Bogus Botox poisoning outbreak spreads to 9 states, CDC says

botox, botulism, CDC, health, injection, outbreak, Science / /

botched shots —

All of the case have been in women, nine of whom were hospitalized.

–

A package of counterfeit Botox.

A package of counterfeit Botox.

At least 19 women across nine US states appear to have been poisoned by bogus injections of Botox, the Centers for Disease Control and Prevention reported late Monday.

Nine of the 19 cases—47 percent—were hospitalized and four—21 percent—were treated with botulinum anti-toxin. The CDC’s alert and outbreak investigation follows reports in recent days of botulism-like illnesses linked to shady injections in Tennessee, where officials reported four cases, and Illinois, where there were two. The CDC now reports that the list of affected states also includes: Colorado, Florida, Kentucky, Nebraska, New Jersey, New York, and Washington.

In a separate alert Tuesday, the Food and Drug Administration said that “unsafe, counterfeit” versions of Botox had been found in several states, and the toxic fakes were administered by unlicensed or untrained people and/or in non-medical or unlicensed settings, such as homes or spas. The counterfeit products appeared to have come from an unlicensed source, generally raising the risks that they’re “misbranded, adulterated, counterfeit, contaminated, improperly stored and transported, ineffective and/or unsafe,” the FDA said.

The CDC and the FDA listed the various symptoms that followed injections of the counterfeit Botox, which include: blurred or double vision, drooping eyelids, difficulty swallowing, dry mouth, slurred speech, constipation, incontinence, shortness of breath or difficulty breathing, weakness, and difficulty lifting one’s head. “These symptoms are similar to those seen when botulinum toxin spreads to other parts of the body,” the FDA wrote. Anyone experiencing those symptoms after an injection should go to the emergency room or contact a health care professional.

Botox is a regulated drug containing purified, controlled doses of botulinum toxin, a neurotoxin made by Clostridium bacteria that causes muscle paralysis by blocking a neurotransmitter. It’s often injected into the face to reduce the appearance of wrinkles. The CDC reported that all 19 cases identified so far are in women between the ages of 25 and 59. Eighteen of the 19 specifically reported getting the injections for cosmetic purposes.

But harmful exposure to the toxin—such as from an infection, eating contaminated foods, or use of counterfeit Botox—can cause botulism or at least botulism-like illnesses. In severe cases, botulism can progress to descending, symmetric muscle weakness, full muscle paralysis, and can sometimes be fatal. The CDC reported that some of the people in the outbreak were hospitalized and treated with anti-toxin out of concern that the toxin had spread beyond the injection site. However, the agency noted that five people were specifically tested for botulism, and all tested negative.

In an email to Ars late last week, the CDC recommended that anyone interested in a Botox injection do so using “an FDA-approved product, administered by licensed providers and in licensed settings.” The agency added in its alert Monday: ” If in doubt, don’t get the injection.”

The FDA, meanwhile, provided detailed information on how to ensure your shot of Botox is the real thing. FDA-approved Botox is made by AbbVie, and authentic Botox products come in unit doses of 50, 100, and 200. The outside of the box should say “BOTOX® COSMETIC / onabotulinumtoxinA / for Injection” or “OnabotulinumtoxinA / BOTOX® / for injection,” and it should list the manufacturer as either “Allergan Aesthetics / An AbbVie Company” or “abbvie.” The active ingredient should be listed as “OnabotulinumtoxinA” on the box.

In contrast, some of the counterfeit versions the FDA has tracked down so far were sold in 150-unit doses (not made by AbbVie), only appear to have “Allergan” on the box (not the full manufacturer name), and the active ingredient is displayed as “Botulinum Toxin Type A” instead of  “OnabotulinumtoxinA.” The counterfeit versions also have had non-English language text on the outside of the box and displayed a lot number of C3709C3. Any one of these features is a sign that the product is counterfeit. Images of the counterfeit products from the FDA are below.

Bogus Botox poisoning outbreak spreads to 9 states, CDC says Read More »

studies-reveal-new-clues-to-how-tardigrades-can-survive-intense-radiation

Studies reveal new clues to how tardigrades can survive intense radiation

animals, Biology, Extremophiles, Genetics, proteins, Science, tardigrades / /

It’s in the genes —

Radiation damages their DNA; they’re just able to repair that damage very quickly.

–

SEM Micrograph of a tardigrade, commonly known as a water bear

Enlarge / SEM Micrograph of a tardigrade, more commonly known as a “water bear” or “moss piglet.”

Cultura RM Exclusive/Gregory S. Paulson/Getty Images

Since the 1960s, scientists have known that the tiny tardigrade can withstand very intense radiation blasts 1,000 times stronger than what most other animals could endure. According to a new paper published in the journal Current Biology, it’s not that such ionizing radiation doesn’t damage tardigrades’ DNA; rather, the tardigrades are able to rapidly repair any such damage. The findings complement those of a separate study published in January that also explored tardigrades’ response to radiation.

“These animals are mounting an incredible response to radiation, and that seems to be a secret to their extreme survival abilities,” said co-author Courtney Clark-Hachtel, who was a postdoc in Bob Goldstein’s lab at the University of North Carolina at Chapel Hill, which has been conducting research into tardigrades for 25 years. “What we are learning about how tardigrades overcome radiation stress can lead to new ideas about how we might try to protect other animals and microorganisms from damaging radiation.”

As reported previously, tardigrades are micro-animals that can survive in the harshest conditions: extreme pressure, extreme temperature, radiation, dehydration, starvation—even exposure to the vacuum of outer space. The creatures were first described by German zoologist Johann Goeze in 1773. They were dubbed tardigrada (“slow steppers” or “slow walkers”) four years later by Lazzaro Spallanzani, an Italian biologist. That’s because tardigrades tend to lumber along like a bear. Since they can survive almost anywhere, they can be found in lots of places: deep-sea trenches, salt and freshwater sediments, tropical rain forests, the Antarctic, mud volcanoes, sand dunes, beaches, and lichen and moss. (Another name for them is “moss piglets.”)

When their moist habitat dries up, however, tardigrades go into a state known as “tun”—a kind of suspended animation, which the animals can remain in for as long as 10 years. When water begins to flow again, water bears absorb it to rehydrate and return to life. They’re not technically members of the extremophile class of organisms since they don’t so much thrive in extreme conditions as endure; technically, they belong to the class of extremotolerant organisms. But their hardiness makes tardigrades a favorite research subject for scientists.

For instance, a 2017 study demonstrated that tardigrades use a special kind of disordered protein to literally suspend their cells in a glass-like matrix that prevents damage. The researchers dubbed this a “tardigrade-specific intrinsically disordered protein” (TDP). In other words, the cells become vitrified. The more TDP genes a tardigrade species has, the more quickly and efficiently it goes into the tun state.

In 2021, another team of Japanese scientists called this “vitrification” hypothesis into question, citing experimental data suggesting that the 2017 findings could be attributed to water retention of the proteins. The following year, researchers at the University of Tokyo identified the mechanism to explain how tardigrades can survive extreme dehydration: cytoplasmic-abundant heat soluble (CAHS) proteins that form a protective gel-like network of filaments to protect dried-out cells. When the tardigrade rehydrates, the filaments gradually recede, ensuring that the cell isn’t stressed or damaged as it regains water.

When it comes to withstanding ionizing radiation, a 2016 study identified a DNA damage suppressor protein dubbed “Dsup” that seemed to shield tardigrade genes implanted into human cells from radiation damage. However, according to Clark-Hatchel et al., it still wasn’t clear whether this kind of protective mechanism was sufficient to fully account for tardigrades’ ability to withstand extreme radiation. Other species of tardigrade seem to lack Dsup proteins, yet still have the same high radiation tolerance, which suggests there could be other factors at play.

A team of French researchers at the French National Museum of Natural History in Paris ran a series of experiments in which they zapped water bear specimens with powerful gamma rays that would be lethal to humans. They published their results earlier this year in the journal eLife. The French team found that gamma rays did actually damage the tardigrade DNA, much like they would damage human cells. Since the tardigrades survived, this suggested the tardigrades were able to quickly repair the damaged DNA.

Further experiments with three different species (including one that lacks Dsup proteins) revealed the tardigrades were producing very high amounts of DNA repair proteins. They also found a similar uptick of proteins unique to tardigrades, most notably tardigrade DNA damage response protein 1 (TDR1), which seems to protect DNA from radiation. “We found that TDR1 protein interacts with DNA and forms aggregates at high concentration suggesting it may condensate DNA and act by preserving chromosome organization until DNA repair is accomplished,” the authors wrote.

Clark-Hatchel et al. independently arrived at similar conclusions from their own experiments. Taken together, the two studies confirm that this extremely rapid up-regulation of many DNA repair genes in response to exposure to ionizing radiation should be sufficient to explain the creatures’ impressive resistance to that radiation. It’s possible that there is a “synergy between protective and repair mechanisms” when it comes to tardigrade tolerance of ionizing radiation.

That said, “Why tardigrades have evolved a strong IR tolerance is enigmatic given that it is unlikely that tardigrades were exposed to high doses of ionizing radiation in their evolutionary history,” Clark-Hatchel et al. wrote.  They thought there could be a link to the mechanisms that enable tardigrades to survive extreme dehydration, which can also result in damaged DNA. Revisiting data from desiccation experiments did not show nearly as strong an increase in DNA repair transcripts, but the authors suggest that the uptick could occur later in the process, upon rehydration—an intriguing topic for future research.

Current Biology, 2024. DOI: 10.1016/j.cub.2024.03.019  (About DOIs).

eLife, 2024. DOI: 10.7554/eLife.92621.1

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second-biggest-black-hole-in-the-milky-way-found

Second-biggest black hole in the Milky Way found

astronomy, astrophysics, black holes, Gaia, Science, stars / /
A dark background with a bright point at the end of a curved path, and a small red circle.

Enlarge / The star’s orbit, shown here in light, is influenced by the far more massive black hole, indicated by the red orbit.

As far as black holes go, there are two categories: supermassive ones that live at the center of the galaxies (and we’re unsure about how they got there) and stellar mass ones that formed through the supernovae that end the lives of massive stars.

Prior to the advent of gravitational wave detectors, the heaviest stellar-mass black hole we knew about was only a bit more than a dozen times the mass of the Sun. And this makes sense, given that the violence of the supernova explosions that form these black holes ensures that only a fraction of the dying star’s mass gets transferred into its dark offspring. But then the gravitational wave data started flowing in, and we discovered there were lots of heavier black holes, with masses dozens of times that of the Sun. But we could only find them when they smacked into another black hole.

Now, thanks to the Gaia mission, we have observational evidence of the largest black hole in the Milky Way outside of the supermassive one, with a mass 33 times that of the Sun. And, in galactic terms, it’s right next door at about 2,000 light-years distant, meaning it will be relatively easy to learn more.

Mapping the stars

Although stellar-mass black holes are several times the mass of the Sun, they aren’t really all that heavy in the grand scheme of things. The sorts of stars that tend to leave black holes behind also tend to lead violent existences, spewing a lot of themselves into space before dying. And the supernova that forms the black hole obviously expels a lot of the star’s mass, rather than feeding it into the black hole. It had been thought that these processes set limits on how big a stellar mass black hole could be when it forms.

The discovery of larger black holes through gravitational wave detectors suggested that this wasn’t true. While there are ways for black holes to get bigger after they form—excessive feeding, mergers—it wasn’t clear that these events occurred often enough to explain the frequency of heavy black holes that we were seeing. And detecting them via gravitational waves doesn’t tell us anything about the history of how they got that large.

Which is why the discovery of Gaia BH3 (which is what the research team is using to avoid having to retype Gaia DR3 4318465066420528000 all the time) is so intriguing. The black hole is sitting calmly in a binary system, not doing anything in particular. But we know it’s there due to its gravitational influence.

Gaia is an ESA mission to map the location and movement of many of the Milky Way’s brighter stars by imaging them multiple times from different perspectives. It also gathers basic data on the stars’ light, allowing us to estimate things like age and composition. And, in addition to their movement across the galaxy, Gaia can measure their movement relative to Earth, a method that is useful for the detection of orbital interactions, such as the presence of companion stars or exoplanets.

The Gaia team was busy preparing for the fourth release of the data from the spacecraft and were running validation tests on the software used to detect binary star systems when they stumbled across Gaia BH3. While normally they’d publish its discovery at the same time as the data release, they consider the new object too important to wait: “We took the exceptional step of the publication of this paper based on preliminary data ahead of the official DR4 due to the unique nature of the discovery, which we believe should not be kept from the scientific community until the next release.”

Finding the invisible

Every star in our galaxy is in motion relative to every other. They orbit the center of our galaxy and may have a history that has imparted additional momentum—gravitational interactions with neighbors, having been part of a smaller galaxy that was consumed by the Milky Way, and so on. But that motion only changes on very long time scales. By contrast, any star in an orbit experiences regular changes in its motion in addition to its overall travel through the galaxy. As part of processing its data, the Gaia team attempts to identify both overall motion and any indications that a star is orbiting as part of a binary system.

The star that is orbiting Gaia BH3 is similar in mass to the Sun but shows the sort of periodic wobbles that indicate it’s in a mutual orbit with a companion. The companion itself, however, was completely invisible, which means it is almost certainly a black hole (the Gaia data had already been used to identify black holes this way). And, based on the mass and orbital motion of the visible star, it’s possible to estimate the mass of the invisible companion.

The estimate ended up being 32 solar masses, which is significantly larger than anything else identified in the Gaia dataset. So, the Gaia team wanted to confirm this wasn’t a software issue and used Earth-based telescopes to observe the same system. Three different observatories confirmed it was there, and the resulting mass estimates were slightly larger than those derived from the Gaia data alone: just under 33 solar masses.

Assuming it’s a single object and not two black holes orbiting each other closely, that makes it the largest non-supermassive black hole known in the Milky Way. And it places it in the mass range that had been difficult to explain via formations in supernovae.

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