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Enlarge / Artist's conception of the early Solar System, which was at risk of a nearby supernova. (credit: NASA/JPL-Caltech)
Stars are thought to form within enormous filaments of molecular gas. Regions where one or more of these filaments meet, known as hubs, are where massive stars form.
These massive stars, located nearby, would have put the early Solar System at risk of a powerful supernova. This risk is more than just hypothetical; a research team at the National Astronomical Observatory of Japan, led by astrophysicist Doris Arzoumanian, looked at isotopes found in ancient meteorites, finding possible evidence of a massive star’s turbulent death.
So why did the Solar System survive? The gas within the filament seems to be able to protect it from the supernova and its onslaught of radioactive isotopes. “The host filament can shield the young Solar System from stellar feedback, both during the formation and evolution of stars (stellar outflow, wind, and radiation) and at the end of their lives (supernovae),” Arzoumanian and her team said in a study recently published in The Astrophysical Journal Letters.
Enlarge / In 1900, Charles Stewart Rolls (one of the founders of Rolls-Royce) said, "The electric car is perfectly noiseless and clean. There is no smell or vibration. They should become very useful when fixed charging stations can be arranged." Now, that's happened, and they are indeed very useful. (credit: Jonathan Gitlin)
A fully electric Rolls-Royce has been some years in the making. Back in 1900, Charles Stewart Rolls proclaimed the electric motor's suitability for automobiles—silent, smooth, and exhaust-free are all great attributes for a luxury car. Back then, the problem was a lack of charging stations, something that appears to be improving 123 years later. That means the world is now ready for the Spectre.
As you might expect of a car wearing the pantheon grille and Spirit of Ecstasy mascot—subtly redesigned here for improved aerodynamic efficiency—there is little shy or retiring about the Spectre, particularly when it's a vivid purple, as was the case for our test car.
My favorite design detail isn't captured well, but the way the spoiler kicks up subtly at the rear is wonderful. (credit: Jonathan Gitlin)
It's a two-door, four-seat coupe, and big one, too: 215.6 inches (5,475 mm) long, 79.4 inches (2,017 mm) wide, and 61.9 inches (1,573 mm) tall, with a curb weight of 6,371 lbs (2,890 kg). Despite that, the somewhat Art Deco-inspired shape cleaves the air with a drag coefficient of 0.25—the shape spent more than 800 hours being refined in the wind tunnel, which is about twice as much time as F1 cars are currently allowed.
Researchers say that nearly 336,000 devices exposed to the Internet remain vulnerable to a critical vulnerability in firewalls sold by Fortinet because admins have yet to install patches the company released three weeks ago.
CVE-2023-27997 is a remote code execution in Fortigate VPNs, which are included in the company’s firewalls. The vulnerability, which stems from a heap overflow bug, has a severity rating of 9.8 out of 10. Fortinet released updates silently patching the flaw on June 8 and disclosed it four days later in an advisory that said it may have been exploited in targeted attacks. That same day, the US Cybersecurity and Infrastructure Security Administration added it to its catalog of known exploited vulnerabilities and gave federal agencies until Tuesday to patch it.
Despite the severity and the availability of a patch, admins have been slow to fix it, researchers said.
Ask Me Anything (AMA) has been a Reddit staple that helped popularize the social media platform. It delivered some unique, personal, and, at times, fiery interviews between public figures and people who submitted questions. The Q&A format became so popular that many people host so-called AMAs these days, but the main subreddit has been r/IAmA, where the likes of then-US President Barack Obama and Bill Gates have sat in the virtual hot seat. But that subreddit, which has been called its own "juggernaut of a media brand," is about to look a lot different and likely less reputable.
On July 1, Reddit moved forward with changes to its API pricing that has infuriated a large and influential portion of its user base. High pricing and a 30-day adjustment period resulted in many third-party Reddit apps closing and others moving to paid-for models that developers are unsure are sustainable.
The latest casualty in the Reddit battle has a profound impact on one of the most famous forms of Reddit content and signals a potential trend in Reddit content changing for the worse.
Enlarge / A myriad of ways one might react to Gfycat's closure, trending on Gfycat itself at the moment. (credit: Gfycat)
The Internet continues to get a bit more fragmented and less accessible every week. Within the past seven days, Reddit finished its purge of third-party clients, Twitter required accounts to view tweets (temporarily or not), and Google News started pulling news articles from its Canadian results.
Now there's one more to add: Gfycat, a place where users uploaded, created, and distributed GIFs of all sorts, is shutting down as of September 1, according to a message on its homepage.
Users of the Snap-owned service are asked to "Please save or delete your Gfycat content." "After September 1, 2023, all Gfycat content and data will be deleted from gfycat.com."
On July 1, laws requiring adult websites to verify user ages took effect in Mississippi and Virginia, despite efforts by Pornhub to push back against the legislation. Those efforts include Pornhub blocking access to users in these states and rallying users to help persuade lawmakers that requiring ID to access adult content will only create more harm for users in their states.
Pornhub posted a long statement on Twitter, explaining that the company thinks US officials acting to prevent children from accessing adult content is "great." However, "the way many elected officials have chosen to implement these laws is haphazard and dangerous."
Pornhub isn't the only one protesting these laws. Last month, the Free Speech Coalition (FSC) sued Louisiana over its age-verification law, with FSC Executive Director Alison Boden alleging that these kinds of laws now passed in seven states are unconstitutional.
Enlarge / A Wendy's old-fashion burger. Romaine lettuce on Wendy's burgers is thought to be the cause of the outbreak. (credit: Getty | Francis Dean)
We will never know for certain what caused a large, multistate outbreak of E. coli O157:H7 infections linked to Wendy's restaurants late last year, according to a new study led by investigators at the Centers for Disease Control and Prevention.
The study, highlighting weaknesses in our ability to respond to foodborne outbreaks, lands amid a separate report published by the CDC finding that, in general, we're also failing to prevent outbreaks. In fact, cases from some common foodborne pathogens have increased relative to pre-pandemic levels.
In the outbreak last year, which spanned from July to August, at least 109 people in six states fell ill, with 52 needing to be hospitalized. Eating at Wendy's was a clear link. But it wasn't enough to crack the case.
Enlarge (credit: Getty Images | NurPhoto )
Twitter has imposed limits on how many tweets users can view each day, with owner Elon Musk claiming the drastic change was needed to fight "data scraping" and other "manipulation." Users who hit the rate limits were greeted with error messages like "Sorry, you are rate limited. Please wait a few moments then try again."
"To address extreme levels of data scraping & system manipulation, we've applied the following temporary limits: - Verified accounts are limited to reading 6000 posts/day - Unverified accounts to 600 posts/day - New unverified accounts to 300/day," Musk wrote on Saturday.
When Musk says "verified," of course, he means users who pay $8 a month for the Twitter Blue subscription that comes with certain perks, such as adding a blue checkmark to the accounts of subscribers. Prior to Musk's ownership of Twitter, "verified" meant that a user had been confirmed to be notable and authentic.
Enlarge / This is Apple’s Vision Pro headset. It looks a bit like a particularly bulky pair of ski goggles, with the materials and design language of Apple’s AirPods Max headphones. (credit: Samuel Axon)
Apple has been forced to make drastic cuts to production forecasts for the mixed-reality Vision Pro headset, unveiled last month after seven years in development and hailed as its most significant product launch since the iPhone.
The complexity of the headset design and difficulties in production are behind the scaling back of targets, while plans for a more affordable version of the device have had to be pushed back, according to multiple people with direct knowledge of the manufacturing process.
Apple has already flagged that the $3,500 “spatial computing” headset device will not go on sale until “early next year,” a lengthy gap from its June 5 launch. Analysts have interpreted this as being more to do with supply chain problems than allowing developers time to create apps for the Vision Pro.
Enlarge (credit: D. Anschutz)
There is a reason countless songs about loneliness exist. Many are relatable, since feeling alone is often part of being human. But a particular song or experience that resonates with one lonely person may mean nothing to someone else who feels isolated and misunderstood.
Human beings are social creatures. Those who feel left out often experience loneliness. To investigate what goes on in the brains of lonely people, a team of researchers at the University of California, Los Angeles, conducted noninvasive brain scans on subjects and found something surprising. The scans revealed that non-lonely individuals were all found to have a similar way of processing the world around them. Lonely people not only interpret things differently from their non-lonely peers, but they even see them differently from each other.
“Our results suggest that lonely people process the world idiosyncratically, which may contribute to the reduced sense of being understood that often accompanies loneliness,” the research team, led by psychologist Elisa Baek, said in a study recently published in Psychological Science.
Enlarge / Pictured: Apple's 2022 Studio Display. (credit: Andrew Cunningham)
In the subscribers-only section of his weekly newsletter, Bloomberg reporter Mark Gurman (who has reported accurately on new Apple hardware in the past) claims that Apple will introduce an external Mac monitor that can act as a smart home display when a Mac goes to sleep or is shut down.
The feature would be available on at least one monitor in an upcoming lineup that will likely include successors to Apple's Pro Display XDR and Studio Display. The newsletter didn't go into much detail about the upcoming displays beyond the smart home feature.
Like the Studio Display, a new monitor with smart home capabilities would run on a chip first seen in the iPhone. The Studio Display contains Apple's A13 chip—the same seen in the iPhone 11 line of smartphones. The upcoming smart display could potentially run on the A16 seen in the iPhone 14 Pro, since that device introduced a similar always-on display feature to Apple's smartphone lineup.
Enlarge / Are we certain this famous Valve promo image wasn't generated by an AI? (credit: Valve)
Last week, we shared an anonymous report that Valve was blocking from Steam at least some games that make use of AI-generated artwork. Over the weekend, Valve confirmed that report, telling Ars in an e-mailed statement that the company is blocking games that use AI-generated content unless developers can prove those AI models were trained with data that does not "infringe on existing copyrights."
"The introduction of AI can sometimes make it harder to show that a developer has sufficient rights in using AI to create assets, including images, text, and music," Valve spokesperson Kaci Boyle told Ars. "In particular, there is some legal uncertainty relating to data used to train AI models. It is the developer's responsibility to make sure they have the appropriate rights to ship their game."
Boyle stressed in the statement that Valve's "goal is not to discourage the use of [AI-generated content] on Steam" and that the company's "priority, as always, is to try to ship as many of the titles we receive as we can." Generative AI is "bound to create new and exciting experiences in gaming," Valve continued.
Enlarge / The Ariane 5 has been a workhorse since 1996 for the European Space Agency. (credit: ESA/Arianespace)
The Ariane 5 rocket has had a long run, with nearly three decades of service launching satellites and spacecraft. Over that time, the iconic rocket, with a liquid hydrogen-fueled core stage and solid rocket boosters, has come to symbolize Europe's guaranteed access to space.
But now, the road is ending for the Ariane 5. As soon as Tuesday evening, the final Ariane 5 rocket will lift off from Kourou, French Guiana, carrying a French military communications satellite and a German communications satellite to geostationary transfer orbit. A 90-minute launch window opens at 5:30 pm ET (21:30 UTC). The launch will be webcast on ESA TV.
And after this? Europe's space agency faces some difficult questions.
Enlarge / Artist's view of what InSight looked like after landing. (credit: NASA/JPL-Caltech)
Mars appears to be a frozen expanse of red dust, gaping craters, and rocky terrain on the outside—but what lies beneath its wind-blasted surface? NASA’s InSight lander might have discovered this before it took its proverbial last breaths in a dust storm.
Whether the core of Mars is solid or liquid has been long debated. While there is no way to observe the Martian core directly, InSight tried. Its seismometer, SEIS, was the first instrument to find possible evidence of a liquid core. In the meantime, its RISE (Rotation and Interior Structure Experiment) instrument had been measuring minuscule changes in the planet’s rotation as it orbited, “wobbles” in its axis caused by the push and pull of the Sun’s gravity.
“Our analysis of InSight’s radio tracking data argues against the existence of a solid inner core and reveals the shape of the core, indicating that there are internal mass anomalies deep within the mantle,” write the researchers behind the instrument in a study recently published in Nature.
Enlarge / SpaceX's Falcon 9 rocket soars through the sky over Cape Canaveral with Europe's Euclid space telescope. (credit: Stephen Clark/Ars Technica)
A European Space Agency telescope launched Saturday on top of a SpaceX Falcon 9 rocket from Florida to begin a $1.5 billion mission seeking to answer fundamental questions about the unseen forces driving the expansion of the Universe. The Euclid telescope, named for the ancient Greek mathematician, will observe billions of galaxies during its six-year survey of the sky, measuring their shapes and positions going back 10 billion years, more than 70 percent of cosmic history.
Led by the European Space Agency, the Euclid mission has the ambitious goal of helping astronomers and cosmologists learn about the properties and influence of dark matter and dark energy, which are thought to make up about 95 percent of the Universe. The rest of the cosmos is made of regular atoms and molecules that we can see and touch.
“To highlight the challenge we face, I would like to give the analogy: It’s very difficult to find a black cat in a dark room, especially if there’s no cat,” said Henk Hoekstra, a professor and cosmologist at Leiden Observatory in the Netherlands. “That’s a little bit of the situation we find ourselves in because we have these observations … But we lack a good theory. So far, nobody has come up with a good explanation for dark matter or dark energy.”
Every person starts as just one fertilized egg. By adulthood, that single cell has turned into roughly 37 trillion cells, many of which keep dividing to create the same amount of fresh human cells every few months.
But those cells have a formidable challenge. The average dividing cell must copy—perfectly—3.2 billion base pairs of DNA, about once every 24 hours. The cell’s replication machinery does an amazing job of this, copying genetic material at a lickety-split pace of some 50 base pairs per second.
Still, that’s much too slow to duplicate the entirety of the human genome. If the cell’s copying machinery started at the tip of each of the 46 chromosomes at the same time, it would finish the longest chromosome—No. 1, at 249 million base pairs—in about two months.
“The way cells get around this, of course, is that they start replication in multiple spots,” says James Berger, a structural biologist at the Johns Hopkins University School of Medicine in Baltimore, who co-authored an article on DNA replication in eukaryotes in the 2021 Annual Review of Biochemistry. Yeast cells have hundreds of potential replication origins, as they’re called, and animals like mice and people have tens of thousands of them, sprinkled throughout their genomes.
“But that poses its own challenge,” says Berger, “which is, how do you know where to start, and how do you time everything?” Without precision control, some DNA might get copied twice, causing cellular pandemonium.
Keeping tight reins on the kickoff of DNA replication is particularly important to avoid that pandemonium. Today, researchers are making steps toward a full understanding of the molecular checks and balances that have evolved in order to ensure that each origin initiates DNA copying once and only once, to produce precisely one complete new genome.
Bad things can happen if replication doesn’t start correctly. For DNA to be copied, the DNA double helix must open up, and the resulting single strands—each of which serves as a template for building a new, second strand—are vulnerable to breakage. Or the process can get stuck. “You really want to resolve replication quickly,” says John Diffley, a biochemist at the Francis Crick Institute in London. Problems during DNA replication can cause the genome to become disorganized, which is often a key step on the route to cancer.
Some genetic diseases, too, result from problems with DNA replication. For example, Meier-Gorlin syndrome, which involves short stature, small ears, and small or no kneecaps, is caused by mutations in several genes that help to kick off the DNA replication process.
It takes a tightly coordinated dance involving dozens of proteins for the DNA-copying machinery to start replication at the right point in the cell’s life cycle. Researchers have a pretty good idea of which proteins do what, because they’ve managed to make DNA replication happen in cell-free biological mixtures in the lab. They’ve mimicked the first crucial steps in initiation of replication using proteins from yeast—the same kind used to make bread and beer—and they’ve mimicked much of the entire replication process using human versions of replication proteins, too.
The cell controls the start of DNA replication in a two-step process. The whole goal of the process is to control the actions of a crucial enzyme—called a helicase—that unwinds the DNA double helix in preparation for copying it. In the first step, inactive helicases are loaded onto the DNA at the origins, where replication starts. During the second step, the helicases are activated, to unwind the DNA.
Kicking off the process is a cluster of six proteins that sit down at the origins. Called ORC, this cluster is shaped like a double-layer ring with a handy notch that allows it to slide onto the DNA strands, Berger’s team has found.
In baker’s yeast, which is a favorite for scientists studying DNA replication, these start sites are easy to spot: They have a specific, 11- to 17-letter core DNA sequence, rich in adenine and thymine chemical bases. Scientists have watched as ORC grabs onto the DNA and then slides along, scanning for the origin sequence until it finds the right spot.
But in humans and other complex life forms, the start sites aren’t so clearly demarcated, and it’s not quite clear what makes the ORC settle down and grab on, says Alessandro Costa, a structural biologist at the Crick Institute who, with Diffley, wrote about DNA replication initiation in the 2022 Annual Review of Biochemistry. Replication seems more likely to start in places where the genome—normally tightly spooled around proteins called histones—has loosened up.
The initiation of DNA replication starts at the tail end of the previous cell division and continues through the cell cycle phase known as G1. DNA synthesis happens during the S phase. Levels of a protein called CDK are critical to ensuring that DNA is replicated once and only once. When CDK levels are low, helicases can jump onto the DNA and start to unwind it. But repeat binding does not happen because CDK levels rise, and this blocks the helicase from binding again. (credit: Knowable Magazine)
Once ORC has settled onto the DNA, it attracts a second protein complex: one that includes the helicase that will eventually unwind the DNA. Costa and colleagues used electron microscopy to work out how ORC lures in first one helicase, and then another. The helicases are also ring-shaped, and each one opens up to wrap around the double-stranded DNA. Then the two helicases close up again, facing toward each other on the DNA strands, like two beads on a string.
At first, they just sit there, like cars with no gas in the tank. They haven’t been activated yet, and for now the cell goes about its usual business.
Things kick into high gear when a crucial molecule called CDK waves the green flag, jump-starting chemical steps that lure in even more proteins. One of them is DNA polymerase—what Costa calls the “typewriter” that will build new DNA strands—which hitches onto each helicase. Others activate the helicases, which can now burn energy to chug along the DNA.
As this occurs, the helicases change shape, pushing on one DNA strand and pulling on the other. This creates strain on the weak hydrogen bonds that normally hold the two strands together by the bases—the As, Cs, Ts and Gs that make up the rungs of the DNA ladder. The two strands get ripped apart. Costa and colleagues have observed how the two helicases untwist the DNA between them, and they’ve seen how the helicases keep the unbound bases stable and out of the way.
Left: Several genes involved in the initiation of DNA replication (horizontal axis) are amplified—that is, mistakenly copied in extra numbers — to varying degrees (vertical axis) in different cancers. Right: On chromosome 8, a cluster of three genes—shown in green text—are frequently amplified together in certain cancers. (credit: Knowable Magazine)
At first, both helicases are wrapped around both strands of DNA, and they can’t get very far like this, because they are facing each other and will just run into each other. But next, they each undergo a change in position, spitting one DNA strand or the other out of the ring. Now separated, they can jostle past each other, and replication proceeds apace.
Each helicase motors along its single strand, in the opposite direction from the other. They leave the origin behind and yank apart those hydrogen-bonded base pairs as they travel. The DNA polymerase is right behind, copying the DNA letters as they’re freed from their partners.
CDK’s second job is to stop any more helicases from hopping on the origins. Thus, there is one start of replication per origin, ensuring proper copying of the genome—although copying doesn’t begin at the same time at each site. The whole process of DNA replication, in human cells, takes about eight hours.
There is still plenty to be worked out. For one thing, the DNA that’s being copied is not a naked double helix. It’s wrapped around histones and attached to lots of other proteins that are busy turning genes on or off or making RNA copies of the genes. How do those jostling proteins affect each other and avoid getting in each other’s way?
Beyond this fascinating, fundamental biology—a remarkable process essential for all life on Earth—there are implications for diseases like cancer. Scientists already know that faulty replication can destabilize DNA, and an unstable genome that’s prone to mutation may be an early hallmark of cancer development. And they are further investigating links between replication proteins and cancer.
“I think that there are opportunities for therapeutic interventions for these systems,” says Berger, “once we have enough insights about how they work and what they look like.”
Amber Dance, a science writer in the Los Angeles area, also likes to break large tasks into smaller segments: It took her five days to complete the steps to draft this article. This article originally appeared in Knowable Magazine, an independent journalistic endeavor from Annual Reviews. Sign up for the newsletter.
Enlarge / Saturn stars in this near-infrared image taken June 25 by the James Webb Space Telescope. (credit: NASA/ESA/CSA/STSci)
The James Webb Space Telescope has observed Saturn for the first time, completing a family portrait of the Solar System’s ringed planets nearly a year after the mission’s first jaw-dropping image release.
Webb’s near-infrared camera took the picture of Saturn on June 25. Scientists added orange color to the monochrome picture to produce the image released Friday.
The picture shows Saturn’s iconic icy rings shining around the disk of the gas giant, which appears much darker in near-infrared due to the absorption of sunlight by methane particles suspended high in the planet’s atmosphere.
Enlarge / One of the medical clinics suspended by Mexican health authorities in Matamoros, Tamaulipas, Mexico, on May 19, 2023. (credit: Getty | AFP)
Three more people in the US have died from fungal meningitis in an outbreak linked to tainted surgeries in Mexico, bringing the total deaths to seven, the Centers for Disease Control and Prevention reported Thursday.
The total case count remains unchanged from an update earlier this month, with 34 cases in the US: nine confirmed, 10 probable, and 15 suspected. Health officials are investigating 161 others who may have been exposed.
The outbreak is linked to cosmetic surgeries involving epidural anesthesia at two clinics in Matamoros, Mexico, just across the border from Brownsville, Texas. Mexican and US officials suspect that a component of the anesthetic was contaminated, resulting in the pathogenic fungus Fusarium solani being injected directly into people's spinal cords. The tainted surgeries are thought to have occurred between January 1, 2023, to May 13, 2023, around when the clinics were shut down by local health officials.
The Asus Zenfone 10 in a variety of colors. [credit: Asus ]
Lovers of small phones: Meet the Asus Zenfone 10, a tiny little device headlined by a 144 Hz, 5.9-inch, 2400×1080 OLED display. For those asking for a one-hand device, this 146.5 mm×68.1mm×9.4 mm phone is one of the smallest on the market, and it has flagship specs. It's not quite the size of the iPhone SE (138.4 mm×67.3 mm×7.3 mm) or the microscopic iPhone 13 Mini (131.5 mm×64.2mm×7.7 mm) but on Android, this is as small as you're going to get.
With those flagship specs, you get a Qualcomm Snapdragon 8 gen 2 SoC, a baseline of 8GB of RAM with an option for 16GB, and UFS 4.0 storage options of 128GB, 256GB, or 512GB. The big downside to a small phone is the battery, which here is only 4300 mAh. Asus somehow found room to pack in a 3.5-mm headphone jack, along with 15 W wireless charging (wired is 30 W), stereo speakers, NFC, IP68 dust and water resistance, Wi-Fi 7, and Bluetooth 5.3.
Enlarge (credit: Roberto Machado Noa / Contributor | LightRocket)
Last month, the FBI created a national online database to finally start coordinating law enforcement reports about "swatting" attacks nationwide, NBC News reported yesterday.
Swatting is a form of domestic terrorism that is sometimes deadly and has become more widespread in the US, according to a March report from Hal Berghel, a computer science professor at University of Nevada, Las Vegas. Berghel's report defined swatting as:
A malicious act that involves making fraudulent 911 calls to cause emergency response teams, such as law enforcement special weapons and tactics teams, or SWAT teams (that’s where the gerund’s root comes from), to react forcefully to a nonexistent public threat.
Scott Schubert, of the FBI's Criminal Justice Information Services, told NBC News that the database will help combat the growing swatting problem by facilitating "information sharing between hundreds of police departments and law enforcement agencies across the country pertaining to swatting incidents."
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