"A new front has opened in the longstanding debate over how fast the universe is expanding," writes Science magazine: For years astronomers have argued over a gulf between the expansion rate as measured from galaxies in the local universe and as calculated from studies of the cosmic microwave background (CMB), the afterglow of the Big Bang. The disparity was so large and persistent that some astronomers thought the standard theory of the universe might have to be tweaked. But over the past week, results from NASA's new James Webb Space Telescope orbiting observatory suggest the problem may be more mundane: some systematic error in the strategies used to measure the distance to nearby galaxies.

"The evidence based on these data does not suggest the need for additional physics," says Wendy Freedman of the University of Chicago, who leads [the Carnegie-Chicago Hubble Program, or CCHP] that calculated the expansion rate from JWST data using three different galactic distance measurements and released the results on the arXiv preprint server. (The papers have not yet been peer reviewed.) The methods disagreed about the expansion rate, known as the Hubble constant, or H0, and two were close to the CMB prediction.
Specifically, the team used JWST to measure the distance to 10 local galaxies using three stars with a predictable brightness: Cepheids, the brightest red giant stars, and carbon stars. Science notes that the last two methods "agreed to about 1%, but differed from the Cepheid-based distance by 2.5% to 4%." Combining all three methods the team derived a value "just shy of 70 km/s per Mpc," according to the article — leading the University of Chicago's Freedman to say "There's something systematic in the measurements. Until we can establish unambiguously where the issue lies in the nearby universe, we can't be claiming that there's additional physics in the distant universe."

But the controversy continues, according to Adam Riess of Johns Hopkins University (leader of a team of Hubble Constant researchers known as SH0ES). Riess points out that other teams have used JWST to measure distances with all three methods separately and have come up with values closer to the original SH0ES result. He also questions why CCHP excluded data from telescopes other than JWST. "I don't see a compelling justification for excluding the data they do," he says.
Thanks to long-time Slashdot reader sciencehabit for sharing the article.

Mozilla's interim CEO Laura Chambers "says the company is reinvesting in Firefox after letting it languish in recent years," reports Fast Company, "hoping to reestablish the browser as independent alternative to the likes of Google's Chrome and Apple's Safari.

"But some of those investments, which also include forays into generative AI, may further upset the community that's been sticking with Firefox all these years..." Chambers acknowledges that Mozilla lost sight of Firefox in recent years as it chased opportunities outside the browser, such as VPN service and email masking. When she replaced Mitchell Baker as CEO in February, the company scaled back those other efforts and made Firefox a priority again. "Yes, Mozilla is refocusing on Firefox," she says. "Obviously, it's our core product, so it's an important piece of the business for us, but we think it's also really an important part of the internet."

Some of that focus involves adding features that have become table-stakes in other browsers. In June, Mozilla added vertical tab support in Firefox's experimental branch, echoing a feature that Microsoft's Edge browser helped popularize three years ago. It's also working on tab grouping features and an easier way to switch between user profiles. Mozilla is even revisiting the concept of web apps, in which users can install websites as freestanding desktop applications. Mozilla abandoned work on Progressive Web Apps in Firefox a few years ago to the dismay of many power users, but now it's talking with community members about a potential path forward.

"We haven't always prioritized those features as highly as we should have," Chambers says. "That's been a real shift that's been very felt in the community, that the things they're asking for . . . are really being prioritized and brought to life."
Firefox was criticized for testing a more private alternative to tracking cookies which could make summaries of aggregated data available to advertisers. (Though it was only tested on a few sites, "Privacy-Preserving Attribution" was enabled by default.) But EFF staff technologist Lena Cohen tells Fast Company that approach was "much more privacy-preserving" than Google's proposal for a "Privacy Sandbox." And according to the article, "Mozilla's system only measures the success rate of ads — it doesn't help companies target those ads in the first place — and it's less susceptible to abuse due to limits on how much data is stored and which parties are allowed to access it." In June, Mozilla also announced its acquisition of Anonym, a startup led by former Meta executives that has its own privacy-focused ad measurement system. While Mozilla has no plans to integrate Anonym's tech in Firefox, the move led to even more anxiety about the kind of company Mozilla was becoming. The tension around Firefox stems in part from Mozilla's precarious financial position, which is heavily dependent on royalty payments from Google. In 2022, nearly 86% of Mozilla's revenue came from Google, which paid $510 million to be Firefox's default search engine. Its attempts to diversify, through VPN service and other subscriptions, haven't gained much traction.

Chambers says that becoming less dependent on Google is "absolutely a priority," and acknowledges that building an ad-tech business is one way of doing that. Mozilla is hoping that emerging privacy regulations and wider adoption of anti-tracking tools in web browsers will increase demand for services like Anonym and for systems like Firefox's privacy-preserving ad measurements. Other revenue-generating ideas are forthcoming. Chambers says Mozilla plans to launch new products outside of Firefox under a "design sprint" model, aimed at quickly figuring out what works and what doesn't. It's also making forays into generative AI in Firefox, starting with a chatbot sidebar in the browser's experimental branch.
Chambers "says to expect a bigger marketing push for Firefox in the United States soon, echoing a 'Challenge the default' ad campaign that was successful in Germany last summer. Mozilla's nonprofit ownership structure, and the idea that it's not beholden to corporate interests, figures heavily into those plans."

New preliminary evidence for phosphine and ammonia in Venus's atmosphere deepens the mystery of their origins, suggesting the possibility of a biological source. The detections, made using the James Clerk Maxwell Telescope and the Green Bank Telescope, point to potential microbial life in Venus's clouds despite the planet's extreme surface conditions. Space.com reports: The new detections of phosphine and ammonia were obtained by a team led by Jane Greaves of the University of Cardiff using submillimeter radio wavelength data collected by the James Clerk Maxwell Telescope (JCMT) in Hawaii and the Green Bank Telescope in West Virginia. "We don't know how you make phosphine or ammonia in an oxygenating atmosphere like that of Venus," said team member and astrophysicist Dave Clements of Imperial College, London, in an interview with Space.com. Then again, it's not clear why biology on Earth produces phosphine, either." Whether it's in penguin poop or badger guts, we don't know why bacteria make phosphine, but they do."

The JCMT's initial detection of phosphine on Venus in 2020 by Greaves and her team was met by fierce disagreement from some quarters. This disagreement focused on how the data was processed and whether that was creating spurious signals since observations by other telescopes struggled to detect the phosphine. Clements said those technical disagreements have now been resolved and that the latest measurements, using a new detector on the JCMT called Namakanui (meaning 'Big Eyes' in Hawaiian), have come from three observing campaigns, each providing 140 times as much data as the initial detection. [...]

Clements is open to the possibility that both phosphine and ammonia are being produced by some rare photochemistry in Venus' upper atmosphere involving solar ultraviolet breaking up molecules and allowing phosphine and ammonia to form from the molecular debris. If that is the case, nobody has observed this process yet, not even in the laboratory. Another possibility that has been mooted is that the phosphine could be produced by Venusian volcanoes. Clements also pointed out that the European Space Agency's Jupiter Icy Moons Explorer (JUICE) is making a fly-by of Venus in August 2025 to help slingshot it towards the Jovian system. JUICE carries instruments capable of detecting phosphine and ammonia, but there's no guarantee that its instruments will be switched on and deployed at Venus.

An anonymous reader shared this report from ScienceAlert: NASA's Parker Solar Probe, tasked with taking a close-up look at the Sun's outer corona, has just equalled the record for the fastest-moving human-made object ever. The previous record holder? The Parker Solar Probe, again. The probe was recorded traveling at 635,266 kilometers (394,736 miles) per hour on June 29, the second time it's reached that speed since it launched in 2018. We're talking around 500 times faster than the speed of sound here. It's on course to get even faster too, with a top speed of around 692,000 kph (430,000 mph) expected when it makes its closest approach to the Sun in 2025.
It's the probe's 20th approach to the sun, according to the article, with the probe using Venus "to create a sort of gravity-powered slingshot," according to the article. (NASA has created a nice interactive 3D model of the probe...)

Besides collecting particle samples in 2021, "The probe is eventually going to get nice and close to the swirling mass of ultra-hot plasma surrounding the Sun, and take a wealth of different measurements to help improve our scientific understanding of it."

The world has baked for 12 consecutive months in temperatures 1.5C (2.7F) greater than their average before the fossil fuel era, new data shows. Temperatures between July 2023 and June 2024 were the highest on record, scientists found, creating a year-long stretch in which the Earth was 1.64C hotter than in preindustrial times. From a report: The findings do not mean world leaders have already failed to honour their promises to stop the planet heating 1.5C by the end of the century -- a target that is measured in decadal averages rather than single years -- but that scorching heat will have exposed more people to violent weather. A sustained rise in temperatures above this level also increases the risk of uncertain but catastrophic tipping points.

Carlo Buontempo, director of the Copernicus Climate Change Service, which analysed the data, said the results were not a statistical oddity but a "large and continuing shift" in the climate. "Even if this specific streak of extremes ends at some point, we are bound to see new records being broken as the climate continues to warm," he said. "This is inevitable unless we stop adding greenhouse gases into the atmosphere and the oceans." Copernicus, a scientific organisation that belongs to the EU's space programme, uses billions of measurements from satellites, ships, aircraft and weather stations to track key climate metrics. It found June 2024 was hotter than any other June on record and was the 12th month in a row with temperatures 1.5C greater than their average between 1850 and 1900. Because temperatures in some months had "relatively small margins" above 1.5C, the scientists said, datasets from other climate agencies may not confirm the 12-month temperature streak.

Longtime Slashdot reader Artem S. Tashkinov shares a report from The Hacker News: A group of security researchers from the Graz University of Technology have demonstrated a new side-channel attack known as SnailLoad that could be used to remotely infer a user's web activity. "SnailLoad exploits a bottleneck present on all Internet connections," the researchers said in a study released this week. "This bottleneck influences the latency of network packets, allowing an attacker to infer the current network activity on someone else's Internet connection. An attacker can use this information to infer websites a user visits or videos a user watches." A defining characteristic of the approach is that it obviates the need for carrying out an adversary-in-the-middle (AitM) attack or being in physical proximity to the Wi-Fi connection to sniff network traffic. Specifically, it entails tricking a target into loading a harmless asset (e.g., a file, an image, or an ad) from a threat actor-controlled server, which then exploits the victim's network latency as a side channel to determine online activities on the victim system.

To perform such a fingerprinting attack and glean what video or a website a user might be watching or visiting, the attacker conducts a series of latency measurements of the victim's network connection as the content is being downloaded from the server while they are browsing or viewing. It then involves a post-processing phase that employs a convolutional neural network (CNN) trained with traces from an identical network setup to make the inference with an accuracy of up to 98% for videos and 63% for websites. In other words, due to the network bottleneck on the victim's side, the adversary can deduce the transmitted amount of data by measuring the packet round trip time (RTT). The RTT traces are unique per video and can be used to classify the video watched by the victim. The attack is so named because the attacking server transmits the file at a snail's pace in order to monitor the connection latency over an extended period of time.

Jonathan O'Callaghan reports via Scientific American: Despite more than a century of efforts to show otherwise, it seems Albert Einstein can still do no wrong. Or at least that's the case for his special theory of relativity, which predicts that time ticks slower for objects moving at extremely high speeds. Called time dilation, this effect grows in intensity the closer to the speed of light that something travels, but it is strangely subjective: a passenger on an accelerating starship would experience time passing normally, but external observers would see the starship moving ever slower as its speed approached that of light. As counterintuitive as this effect may be, it has been checked and confirmed in the motions of everything from Earth-orbiting satellites far-distant galaxies. Now a group of scientists have taken such tests one step further by observing more than 1,500 supernovae across the universe to reveal time dilation's effects on a staggering cosmic scale. The researchers' findings, once again, reach an all-too-familiar conclusion. "Einstein is right one more time," says Geraint Lewis of the University of Sydney, a co-author of the study.

In the paper, posted earlier this month on the preprint server arXiv.org, Ryan White of the University of Queensland in Australia and his colleagues used data from the Dark Energy Survey (DES) to investigate time dilation. For the past decade, researchers involved with DES had used the Victor M. Blanco Telescope at the Cerro Tololo Inter-American Observatory in Chile to study particular exploding stars called Type 1a supernovae across billions of years of cosmic history. [...] Type 1a supernovae are keystone cosmic explosions caused when a white dwarf -- the slowly cooling corpse of a midsized star -- siphons so much material from a companion that it ignites a thermonuclear reaction and explodes. This explosion occurs once the growing white dwarf reaches about 1.44 times the mass of our sun, a threshold known as the Chandrasekhar limit. This physical baseline imbues all Type 1a supernovae with a fairly consistent brightness, making them useful cosmic beacons for gauging intergalactic distances. "They should all be essentially the same kind of event no matter where you look in the universe," White says. "They all come from exploding white dwarf stars, which happens at almost exactly the same mass no matter where they are."

The steadfastness of these supernovae across the entire observable universe is what makes them potent probes of time dilation -- nothing else, in principle, should so radically and precisely slow their apparent progression in lockstep with ever-greater distances. Using the dataset of 1,504 supernovae from DES, White's paper shows with astonishing accuracy that this correlation holds true out to a redshift of 1.2, a time when the universe was about five billion years old. "This is the most precise measurement" of cosmological time dilation yet, White says, up to seven times more precise than previous measurements of cosmological time dilation that used fewer supernovae. [...] This particular supernova-focused facet of the Dark Energy Survey has concluded, so until a new dataset is taken, White's measurement of cosmological time dilation is unlikely to be beaten. "It's a pretty definitive measurement," says [Tamara Davis of the University of Queensland, a co-author of the paper]. "You don't really need to do any better." Jonathan O'Callaghan is an award-winning freelance journalist covering astronomy, astrophysics, commercial spaceflight and space exploration.

Astronomers are observing the sudden awakening of a giant black hole in the constellation of Virgo. "Decades of observations found nothing remarkable about the distant galaxy in the constellation of Virgo, but that changed at the end of 2019 when astronomers noticed a dramatic surge in its luminosity that persists to this day," reports The Guardian. "Researchers now believe they are witnessing changes that have never been seen before, with the black hole at the galaxy's core putting on an extreme cosmic light show as vast amounts of material fall into it." From the report: The galaxy, which goes by the snappy codename SDSS1335+0728 and lies 300m light years away, was flagged to astronomers in December 2019 when an observatory in California called the Zwicky Transient Facility recorded a sudden rise in its brightness. The alert prompted a flurry of new observations and checks of archived measurements from ground- and space-based telescopes to understand more about the galaxy and its past behavior.

The scientists discovered the galaxy had recently doubled in brightness in mid-infrared wavelengths, become four times brighter in the ultraviolet, and at least 10 times brighter in the X-ray range. What triggered the sudden brightening is unclear, but writing in Astronomy and Astrophysics, the researchers say the most likely explanation is the creation of an "active galactic nucleus" where a vast black hole at the centre of a galaxy starts actively consuming the material around it.

Active galactic nuclei emit a broad spectrum of light as gas around the black hole heats up and glows, and surrounding dust particles absorb some wavelengths and re-radiate others. But it is not the only possibility. The team has not ruled out an exotic form of "tidal disruption event," a highly restrained phrase to describe a star that is ripped apart after straying too close to a black hole. Tidal disruption events tend to be brief affairs, brightening a galaxy for no more than a few hundred days, but more measurements are needed to rule out the process.

An anonymous reader quotes a report from The Guardian: Dr Joseph Cotter takes some unusual pieces of luggage on his trips on the London underground. They include a stainless steel vacuum chamber, a few billion atoms of rubidium and an array of lasers that are used to cool his equipment to a temperature just above absolute zero. While not the average kit you would expect to find being dragged into carriages on the District Line, this is the gear that Cotter -- who works at Imperial College London's Centre for Cold Matter -- uses on his underground travels. Though the baggage may be bizarre, it has an ambitious purpose. It is being used to develop a quantum compass -- an instrument that will exploit the behavior of subatomic matter in order to develop devices that can accurately pinpoint their locations no matter where they are placed, paving the way for the creation of a new generation of underground and underwater sensors. The ideal place to test it is the London underground, Cotter and his team have discovered. "We are developing very precise new sensors using quantum mechanics, and these are showing great promise in the laboratory," he told the Observer last week. "However, they are less accurate in real-life settings. That is why we are taking our equipment to the London underground. It's the perfect place for smoothing out the rough edges and getting our equipment to work in real life." [...]

At the heart of the quantum compass -- which could be ready for widespread use in a few years -- is a device known as an accelerometer that can measure how an object's velocity changes over time. This information, combined with the starting point of that object, allows its future positions to be calculated. Mobile phones and laptops possess accelerometers but these versions cannot maintain their accuracy over lengthy periods. However, quantum mechanics offers scientists a way to provide new precision and accuracy by measuring properties of supercool atoms. At extremely low temperatures, atoms behave in a "quantum" way. They act like matter and like waves. "When atoms are ultra-cold, we can use quantum mechanics to describe how they move, and this allows us to make accurate measurements that tell us how our device is changing its position," said Cotter. In the devices -- which have been carried on board London underground track-testing trains and not on commuter services -- rubidium is inserted into the vacuum chamber that lies at the machine's heart. Powerful lasers are then used to cool these atoms to a fraction of a degree above absolute zero (-273.15C). In these conditions, the wave properties of the rubidium atoms are affected by the acceleration of the vehicle that is carrying the equipment, and these minute changes can be measured accurately. The system has been found to work well in a stable laboratory but needs to be tested in more extreme conditions if it is to be turned into a transportable, standalone device that can be used in remote or complex locations, added Cotter.

Slashdot reader storagedude shared this report from The Cyber Express: A security researcher discovered an exploitable timing leak in the Kyber key encapsulation mechanism (KEM) that's in the process of being adopted by NIST as a post-quantum cryptographic standard. Antoon Purnal of PQShield detailed his findings in a blog post and on social media, and noted that the problem has been fixed with the help of the Kyber team. The issue was found in the reference implementation of the Module-Lattice-Based Key-Encapsulation Mechanism (ML-KEM) that's in the process of being adopted as a NIST post-quantum key encapsulation standard. "A key part of implementation security is resistance against side-channel attacks, which exploit the physical side-effects of cryptographic computations to infer sensitive information," Purnal wrote.

To secure against side-channel attacks, cryptographic algorithms must be implemented in a way so that "no attacker-observable effect of their execution depends on the secrets they process," he wrote. In the ML-KEM reference implementation, "we're concerned with a particular side channel that's observable in almost all cryptographic deployment scenarios: time." The vulnerability can occur when a compiler optimizes the code, in the process silently undoing "measures taken by the skilled implementer." In Purnal's analysis, the Clang compiler was found to emit a vulnerable secret-dependent branch in the poly_frommsg function of the ML-KEM reference code needed in both key encapsulation and decapsulation, corresponding to the expand_secure implementation.
While the reference implementation was patched, "It's important to note that this does not rule out the possibility that other libraries, which are based on the reference implementation but do not use the poly_frommsg function verbatim, may be vulnerable — either now or in the future," Purnal wrote.

Purnal also published a proof-of-concept demo on GitHub. "On an Intel Core i7-13700H, it takes between 5-10 minutes to leak the entire ML-KEM 512 secret key using end-to-end decapsulation timing measurements."

Carbon dioxide levels in Earth's atmosphere are accumulating "faster than ever" and have reached unprecedented levels, with a peak of 426.9 ppm recorded at NOAA's Mauna Loa Observatory in May 2024, said scientists from NOAA, the Scripps Institution of Oceanography and the University of California San Diego. CBS News reports: "Over the past year, we've experienced the hottest year on record, the hottest ocean temperatures on record, and a seemingly endless string of heat waves, droughts, floods, wildfires and storms," NOAA Administrator Rick Spinrad said in a press release. "Now we are finding that atmospheric CO2 levels are increasing faster than ever." The researchers measured carbon dioxide, or CO2, levels at the Mauna Loa Atmospheric Baseline Observatory. They found that atmospheric levels of the gas hit a seasonal peak of just under 427 parts per million in May -- an increase of 2.9 ppm since May 2023 and the fifth-largest annual growth in 50 years of data recording.

It also made official that the past two years saw the largest jump in the May peak -- when CO2 levels are at their highest in the Northern Hemisphere. John Miller, a NOAA carbon cycle scientist, said that the jump likely stems from the continuous rampant burning of fossil fuels as well as El Nino conditions making the planet's ability to absorb CO2 more difficult. The surge of carbon dioxide levels at the measuring station surpassed even the global average set last year, which was a record high of 419.3 ppm -- 50% higher than it was before the Industrial Revolution. However, NOAA noted that their observations were taken at the observatory specifically, and do not "capture the changes of CO2 across the globe," although global measurements have proven consistent without those at Mauna Loa. "Not only is CO2 now at the highest level in millions of years, it is also rising faster than ever," Ralph Keeling, director of Scripps' CO2 program, said in the release. "Each year achieves a higher maximum due to fossil-fuel burning, which releases pollution in the form of carbon dioxide into the atmosphere. Fossil fuel pollution just keeps building up, much like trash in a landfill."

"We are living in unprecedented times. ... This string of hottest months will be remembered as comparatively cold," Carlo Buontempo, director of Copernicus, added.

The European Union's Copernicus Climate Change Service reported that the past year saw record-breaking heat, with global temperatures surpassing all historical measurements. According to Copernicus, May marked the 12th consecutive month of record-high global temperatures, and exceeded a key Paris Agreement temperature target. The Week reports: The stretch is a "stark warning." In a separate study published Wednesday, a group of 57 scientists found that human activity was responsible for 92% of 2023's warming, which increased at a rate "unprecedented in the instrumental record."

While averting catastrophe is "still just about possible," the decisions made by global leaders "especially in the next 18 months" will determine whether the planet can be saved, U.N. Secretary General Antonio Guterres said in a special address. "We need an exit ramp off the highway to climate hell."

Without serious efforts to reverse global warming, "this string of hottest months will be remembered as comparatively cold," Copernicus Director Carlo Buontempo said. "The 11 months in a row that tied or broke the 1.5C barrier did not yet constitute a breaching of the Paris target, since the benchmark refers to a timescale of multiple decades," notes Axios. "Still, the fact that the climate is now exceeding the target with greater regularity, and is projected to continue doing so, is a sign of the matter's urgency."

The 34-year-old Hubble Space Telescope is now operating with its final two working gyroscopes, necessitating a switch to a less productive "one-gyro" mode to extend its operational life. This contingency plan will reduce Hubble's productivity by over 12%, limit its ability to track fast-moving objects, and decrease the portion of the sky it can observe. That said, NASA expects it to keep functioning through 2035. Science.org reports: Normally, Hubble measures its location in space with a system that includes three gyroscopes -- rapidly spinning wheels that can sense forces in three directions. But in a 4 June press conference, NASA officials said one of the telescope's three remaining gyroscopes is on the fritz. The agency is now invoking a contingency plan: a "one-gyro" mode that keeps the other functioning gyroscope in reserve. The mode will reduce the telescope's productivity by more than 12% but preserve its ability to observe for years to come, Mark Clampin, NASA's astrophysics division director, said at the press conference. "We believe this is our best approach to support Hubble science through this decade and into the next."

Hubble's gyroscopes, which spin at 19,200 revolutions per minute, are extremely precise but finicky. The agency has flown a total of 22 gyroscopes across various servicing missions and is now down to the last two of the six currently onboard. In one-gyro mode, Hubble must rely on its less precise star trackers and other sensors to verify its position, a slower process that leads to reduced productivity. "It will take us more time to slew from one target attitude to the next, and to be able to lock on to that science target," said Patrick Crouse, Hubble's project manager at NASA's Goddard Space Flight Center.

A one-gyro Hubble will also struggle to track fast-moving targets, such as asteroids within the orbit of Mars, and to swivel to spot transient distant phenomena such as supernovae, according to a 2016 report (PDF) from the Space Telescope Science Institute, which operates Hubble. In addition, the inefficiencies of one-gyro mode will reduce the portion of the sky that Hubble can safely point to at any given moment, from 82% to roughly 40%, including a larger avoidance zone near the Sun. It won't be able to observe Venus or the Moon, nor will it be able to reliably spot comets when they're near the Sun. Its ability to scrutinize distant exoplanets will also be hampered, especially in gathering the spectral measurements used to discern alien atmospheres. Furthermore, a one-gyro Hubble won't be able to perform as many simultaneous observations with the new JWST space observatory. Moving forward, the two telescopes' fields of view at any given moment may overlap by less than 20%, according to a 2019 estimate anticipating this event from a Hubble advisory committee.

With the help of NASA's James Webb Space Telescope (JWST), an international team of astronomers discovered a galaxy at a redshift of 14.32, indicating it existed just 290 million years post-Big Bang. In a NASA release today, Stefano Carniani from Scuola Normale Superiore in Pisa, Italy, and Kevin Hainline from the University of Arizona in Tucson, Arizona, described how this source was found and what its unique properties tell us about galaxy formation: "The instruments on Webb were designed to find and understand the earliest galaxies, and in the first year of observations as part of the JWST Advanced Deep Extragalactic Survey (JADES), we found many hundreds of candidate galaxies from the first 650 million years after the big bang. In early 2023, we discovered a galaxy in our data that had strong evidence of being above a redshift of 14, which was very exciting, but there were some properties of the source that made us wary. The source was surprisingly bright, which we wouldn't expect for such a distant galaxy, and it was very close to another galaxy such that the two appeared to be part of one larger object. When we observed the source again in October 2023 as part of the JADES Origins Field, new imaging data obtained with Webb's narrower NIRCam (Near-Infrared Camera) filters pointed even more toward the high-redshift hypothesis. We knew we needed a spectrum, as whatever we would learn would be of immense scientific importance, either as a new milestone in Webb's investigation of the early universe or as a confounding oddball of a middle-aged galaxy.

In January 2024, NIRSpec observed this galaxy, JADES-GS-z14-0, for almost ten hours, and when the spectrum was first processed, there was unambiguous evidence that the galaxy was indeed at a redshift of 14.32, shattering the previous most-distant galaxy record (z = 13.2 of JADES-GS-z13-0). Seeing this spectrum was incredibly exciting for the whole team, given the mystery surrounding the source. This discovery was not just a new distance record for our team; the most important aspect of JADES-GS-z14-0 was that at this distance, we know that this galaxy must be intrinsically very luminous. From the images, the source is found to be over 1,600-light years across, proving that the light we see is coming mostly from young stars and not from emission near a growing supermassive black hole. This much starlight implies that the galaxy is several hundreds of millions of times the mass of the Sun! This raises the question: How can nature make such a bright, massive, and large galaxy in less than 300 million years?

The data reveal other important aspects of this astonishing galaxy. We see that the color of the galaxy is not as blue as it could be, indicating that some of the light is reddened by dust, even at these very early times. JADES researcher Jake Helton of Steward Observatory and the University of Arizona also identified that JADES-GS-z14-0 was detected at longer wavelengths with Webb's MIRI (Mid-Infrared Instrument), a remarkable achievement considering its distance. The MIRI observation covers wavelengths of light that were emitted in the visible-light range, which are redshifted out of reach for Webb's near-infrared instruments. Jake's analysis indicates that the brightness of the source implied by the MIRI observation is above what would be extrapolated from the measurements by the other Webb instruments, indicating the presence of strong ionized gas emission in the galaxy in the form of bright emission lines from hydrogen and oxygen. The presence of oxygen so early in the life of this galaxy is a surprise and suggests that multiple generations of very massive stars had already lived their lives before we observed the galaxy.

All of these observations, together, tell us that JADES-GS-z14-0 is not like the types of galaxies that have been predicted by theoretical models and computer simulations to exist in the very early universe. Given the observed brightness of the source, we can forecast how it might grow over cosmic time, and so far we have not found any suitable analogs from the hundreds of other galaxies we've observed at high redshift in our survey. Given the relatively small region of the sky that we searched to find JADES-GS-z14-0, its discovery has profound implications for the predicted number of bright galaxies we see in the early universe, as discussed in another concurrent JADES study (Robertson et al., recently accepted). It is likely that astronomers will find many such luminous galaxies, possibly at even earlier times, over the next decade with Webb. We're thrilled to see the extraordinary diversity of galaxies that existed at Cosmic Dawn!

An anonymous reader quotes a report from the BBC: A sophisticated joint European-Japanese satellite has launched to measure how clouds influence the climate. Some low-level clouds are known to cool the planet, others at high altitude will act as a blanket. The Earthcare mission will use a laser and a radar to probe the atmosphere to see precisely where the balance lies. It's one of the great uncertainties in the computer models used to forecast how the climate will respond to increasing levels of greenhouse gases. "Many of our models suggest cloud cover will go down in the future and that means that clouds will reflect less sunlight back to space, more will be absorbed at the surface and that will act as an amplifier to the warming we would get from carbon dioxide," Dr Robin Hogan, from the European Centre for Medium-Range Weather Forecasts, told BBC News.

The 2.3-tonne satellite was sent up from California on a SpaceX rocket. The project is led by the European Space Agency (ESA), which has described it as the organization's most complex Earth observation venture to date. Certainly, the technical challenge in getting the instruments to work as intended has been immense. It's taken fully 20 years to go from mission approval to launch. Earthcare will circle the Earth at a height of about 400km (250 miles). It's actually got four instruments in total that will work in unison to get at the information sought by climate scientists.

The simplest is an imager -- a camera that will take pictures of the scene passing below the spacecraft to give context to the measurements made by the other three instruments. Earthcare's European ultraviolet laser will see the thin, high clouds and the tops of clouds lower down. It will also detect the small particles and droplets (aerosols) in the atmosphere that influence the formation and behavior of clouds. The Japanese radar will look into the clouds, to determine how much water they are carrying and how that's precipitating as rain, hail and snow. And a radiometer will sense how much of the energy falling on to Earth from the Sun is being reflected or radiated back into space.

This week Red Hat announced one of America's leading pediatric hospitals is using AI to analyze X-rays, "to improve image quality and the speed and accuracy of image interpretation."

Red Hat's CTO said the move exemplifies "the positive impact AI can have in the healthcare field". Before Boston Children's Hospital began piloting AI in radiology, quantitative measurements had to be done manually, which was a time-consuming task. Other, more complex image analyses were performed completely offline and outside of the clinical workflow. In a field where time is of the essence, the hospital is piloting Red Hat OpenShift via the ChRIS Research Integration Service, a web-based medical image platform. The AI application running in ChRIS on the Red Hat OpenShift foundation has the potential to automatically examine x-rays, identify the most valuable diagnostic images among the thousands taken and flag any discrepancies for the radiologist. This decreases the interpretation time for radiologists.
But it also seems to be a big win for openness: Innovation developed internally is immediately transferable to public research clouds such as the Massachusetts Open Cloud, where large-scale data sharing and additional innovation can be fostered. Boston Children's Hospital aims to extend the reach of advanced healthcare solutions globally through this approach, amplifying their impact on patient well-being worldwide.
"Red Hat believes open unlocks the world's potential," the announcement concludes, "including the potential to share knowledge and build upon each other's discoveries. Additionally, Red Hat believes innovation — including AI — should be available everywhere, making any application, anywhere a reality.

"With open source, enabling AI-fueled innovation across hybrid IT environments that can lead to faster clinical breakthroughs and better patient outcomes is a reality."

The largest ever recorded leap in the amount of carbon dioxide laden in the world's atmosphere has just occurred, according to researchers who monitor the relentless accumulation of the primary gas that is heating the planet. From a report: The global average concentration of carbon dioxide in March this year was 4.7 parts per million (or ppm) higher than it it was in March last year, which is a record-breaking increase in CO2 levels over a 12-month period. The increase has been spurred, scientists say, by the periodic El Nino climate event, which has now waned, as well as the ongoing and increasing amounts of greenhouse gases expelled into the atmosphere due to the burning of fossil fuels and deforestation.

"It's really significant to see the pace of the increase over the first four months of this year, which is also a record," said Ralph Keeling, director of the CO2 Program at UC San Diego's Scripps Institution of Oceanography. "We aren't just breaking records in CO2 concentrations, but also the record in how fast it is rising." The global CO2 readings have been taken from a station perched upon the Mauna Loa volcano in Hawaii since the measurements began in 1958 under Keeling's father, Charles. The concentrations of CO2 have increased each year since, as the heat-trapping gas continues to progressively accumulate due to rampant emissions from power plants, cars, trucks and other sources, with last year hitting a new global record in annual emissions.

NASA last week formally approved a $3.35 billion mission to explore Saturn's largest moon with a quadcopter drone. "Dragonfly is a spectacular science mission with broad community interest, and we are excited to take the next steps on this mission," said Nicky Fox, associate administrator of NASA's science mission directorate. "Exploring Titan will push the boundaries of what we can do with rotorcraft outside of Earth." The mission has a launch date of July 2028. Ars Technica reports: After reaching Titan, the eight-bladed rotorcraft lander will soar from place to place on Saturn's hazy moon, exploring environments rich in organic molecules, the building blocks of life. Dragonfly will be the first mobile robot explorer to land on any other planetary body besides the Moon and Mars, and only the second flying drone to explore another planet. NASA's Ingenuity helicopter on Mars was the first. Dragonfly will be more than 200 times as massive as Ingenuity and will operate six times farther from Earth.

Despite its distant position in the cold outer Solar System, Titan appears to be reminiscent of the ancient Earth. A shroud of orange haze envelops Saturn's largest moon, and Titan's surface is covered with sand dunes and methane lakes. Titan's frigid temperatures -- hovering near minus 290 degrees Fahrenheit (minus 179 degrees Celsius) -- mean water ice behaves like bedrock. NASA's Cassini spacecraft, which flew past Titan numerous times before its mission ended in 2017, discovered weather systems on the hazy moon. Observations from Cassini found evidence for hydrocarbon rains and winds that appear to generate waves in Titan's methane lakes. Clearly, Titan is an exotic world. Most of what scientists know about Titan comes from measurements collected by Cassini and the European Space Agency's Huygens probe, which Cassini released to land on Titan in 2005. Huygens returned the first pictures from Titan's surface, but it only transmitted data for 72 minutes.

Dragonfly will explore Titan for around three years, flying tens of kilometers about once per month to measure the prebiotic chemistry of Titan's surface, study its soupy atmosphere, and search for biosignatures that could be indications of life. The mission will visit more than 30 locations within Titan's equatorial region, according to a presentation by Elizabeth Turtle, Dragonfly's principal investigator at the Johns Hopkins University Applied Physics Laboratory. "The Dragonfly mission is an incredible opportunity to explore an ocean world in a way that we have never done before," Turtle said in a statement. "The team is dedicated and enthusiastic about accomplishing this unprecedented investigation of the complex carbon chemistry that exists on the surface of Titan and the innovative technology bringing this first-of-its-kind space mission to life."

South America's Amazon River has reached its lowest level since measurements began, according to the Washington Post, while temperatures "hovered above 110 degrees Fahrenheit" for nearly a week as April began in the capital of Mali. "Nights offered little relief, with temperatures often staying above 90 degrees..."

"An overtaxed electrical grid sputtered and shut down," they add, and "dehydration and heat stroke became epidemic... At the city's main hospital, doctors recorded a month's worth of deaths in just four days. Local cemeteries were overwhelmed." The historic heat wave that besieged Mali and other parts of West Africa this month — which scientists say would have been "virtually impossible" in a world without human-caused climate change — is just the latest manifestation of a sudden and worrying surge in global temperatures. Fueled by decades of uncontrolled fossil fuel burning and an El Niño climate pattern that emerged last June, the planet this year breached a feared warming threshold of 1.5 degrees Celsius above preindustrial levels. Nearly 19,000 weather stations have notched record high temperatures since January 1. Each of the last ten months has been the hottest of its kind.

The scale and intensity of this hot streak is extraordinary even considering the unprecedented amount of greenhouse gases in the atmosphere, researchers say. Scientists are still struggling to explain how the planet could have exceeded previous temperature records by as much as half a degree Celsius (0.9 degrees Fahrenheit) last fall. What happens in the next few months, said Gavin Schmidt, director of the NASA Goddard Institute for Space Studies, could indicate whether Earth's climate has undergone a fundamental shift — a quantum leap in warming that is confounding climate models and stoking ever more dangerous weather extremes.

But even if the world returns to a more predictable warming trajectory, it will only be a temporary reprieve from the conditions that humanity must soon confront, Schmidt said. "Global warming continues apace."
Will this summer's La Niña cool things off? More atmospheric research is underway, and "Schmidt says it's too soon to know how worried the world should be," according to the article. But he does raise this possibility. "What if the statistical connections that we are basing our predictions on are no longer valid?"

"It's niggling at the back of my brain that it could be that the past is no longer a guide to the future."

An anonymous reader quotes a report from The Guardian: Only seven countries are meeting an international air quality standard, with deadly air pollution worsening in places due to a rebound in economic activity and the toxic impact of wildfire smoke, a new report has found. Of 134 countries and regions surveyed in the report, only seven -- Australia, Estonia, Finland, Grenada, Iceland, Mauritius and New Zealand -- are meeting a World Health Organization (WHO) guideline limit for tiny airborne particles expelled by cars, trucks and industrial processes. The vast majority of countries are failing to meet this standard for PM2.5, a type of microscopic speck of soot less than the width of a human hair that when inhaled can cause a myriad of health problems and deaths, risking serious implications for people, according to the report by IQAir, a Swiss air quality organization that draws data from more than 30,000 monitoring stations around the world.

While the world's air is generally much cleaner than it was in much of the past century, there are still places where the pollution levels are particularly dangerous. The most polluted country, Pakistan, has PM2.5 levels more than 14 times higher than the WHO standard, the IQAir report found, with India, Tajikistan and Burkina Faso the next most polluted countries. But even in wealthy and fast-developing countries, progress in cutting air pollution is under threat. Canada, long considered as having some of the cleanest air in the western world, became the worst for PM2.5 last year due to record wildfires that ravaged the country, sending toxic spoke spewing across the country and into the US. In China, meanwhile, improvements in air quality were complicated last year by a rebound in economic activity in the wake of the Covid-19 pandemic, with the report finding a 6.5% increase in PM2.5 levels.

The most polluted urban area in the world last year was Begusarai in India, the sixth annual IQAir report found, with India home to the four most polluted cities in the world. Much of the developing world, particularly countries in Africa, lacks reliable air quality measurements, however. The WHO lowered its guideline for "safe" PM2.5 levels in 2021 to five micrograms per cubic meter and by this measure many countries, such as those in Europe that have cleaned up their air significantly in the past 20 years, fall short. But even this more stringent guideline may not fully capture the risk of insidious air pollution. Research released by US scientists last month found there is no safe level of PM2.5, with even the smallest exposures linked to an increase in hospitalizations for conditions such as heart disease and asthma.