Tech
Researchers spot black hole feeding at 40x its theoretical limit
How did supermassive black holes end up at the center of every galaxy? A while back, it wasn't that hard to explain: That's where the highest concentration of matter is, and the black holes had billions of years to feed on it. But as we've looked ever deeper into the Universe's history, we keep finding supermassive black holes, which shortens the timeline for their formation. Rather than making a leisurely meal of nearby matter, these black holes have gorged themselves in a feeding frenzy.
With the advent of the Webb Space Telescope, the problem has pushed up against theoretical limits. The matter falling into a black hole generates radiation, with faster feeding meaning more radiation. And that radiation can drive off nearby matter, choking off the black hole's food supply. That sets a limit on how fast black holes can grow unless matter is somehow fed directly into them. The Webb was used to identify early supermassive black holes that needed to have been pushing against the limit for their entire existence.
But the Webb may have just identified a solution to the dilemma as well. It has spotted a black hole that appears to have been feeding at 40 times the theoretical limit for millions of years, allowing growth at a pace sufficient to build a supermassive black hole.
The Trek Checkpoint SL 7 AXS Gen 3 may be the perfect gravel bike
As I followed a friend down a flow-y, undulating single-track trail, I started laughing. Unlike my mountain bike-riding companion, I was on a gravel bike, the new Trek Checkpoint SL 7 AXS Gen 3. You might be wondering why a review of a gravel bike is starting with such a ride. The answer is simple—the Checkpoint had excelled everywhere else I rode it, so I was curious to see how it would fare on a non-technical MTB track. Amazingly well, as it turns out.
Unlike every other bike Ars has reviewed to this point, the Checkpoint SL 7 Gen 3 has no motor—there's no e- in this bike, as the only batteries are for shifting.. As is the case with our other bike reviews, sometimes we ask for a specific model, but manufacturers tend to contact us when we’ve already got a garage full of bikes we’ve not finished the reviews for (there are currently 12 bikes in my garage, some of which belong to other family members).
Launched in 2018, the Checkpoint is Trek's gravel-centric bike. For 2025, Trek has split its gravel lineup into the third-generation Checkpoint Trek and the Checkmate SLR 9 AXS. The latter features a lighter-weight frame, a power meter, and SRAM's new Red XPLR groupset. Selling for $11,999, the Checkmate is a gravel racer. Priced several thousand less at $5,699, the Checkpoint SL 7 AXS is now Trek's top gravel bike for those looking for a fun day out on the trails.
Guy makes “dodgy e-bike” from 130 used vapes to make point about e-waste
Disposable vapes are indefensible. Many, or maybe most, of them contain rechargeable lithium-ion batteries, but manufacturers prefer to sell new ones. More than 260 million vape batteries are estimated to enter the trash stream every year in the UK alone. Vapers and vape makers are simply leaving an e-waste epidemic to the planet's future residents to sort out.
To make a point about how wasteful this practice is—and to also make a pretty rad project and video—Chris Doel took 130 disposable vape batteries (the bigger "3,500 puff" types with model 20400 cells) found littered at a music festival and converted them into a 48-volt, 1,500-watt e-bike battery, one that powered an e-bike with almost no pedaling more than 20 miles. You can see the whole build and watch Doel zoom along trails on his YouTube video.
A pile of empty aluminum vape shells, and the juice and batteries that came out of them, on Chris Doel's workstation. Credit: A pile of empty aluminum Vape batteries, put into group cases, wired together in batches, and then wired in serial into two stacks, next to a multimeter. Credit: Chris Doel How the battery fits onto the bike that Chris Doel powers with vape batteries: a big bag, ratchet straps, and wiring to a rear hub motor. Just, one more time, folks: do not do this at home. Credit: Chris DoelTo be clear: Do not do this. Do not put disposable vape cartridges in a vise clamp to "pop out" their components. Do not desolder them from vape cartridges that have a surprising amount of concentration still in them. Do not wire them together using a balance board, group them using 3D-printed cell holders, and then wire them in series. Heck, do not put that much power into a rear hub on a standard bike frame, at least more than once. Doel has a fire extinguisher present and visible on his workbench, and he shows you what happens when two of the wrong batteries happen to make momentary contact—smoke, coughing, and strong warnings.
What this 500-year-old shipwreck can tell us about how we age
Henry VIII's favorite warship, the Mary Rose, sank in battle in 1545. Archaeologists successfully raised the ship in 1982, along with thousands of articles and the remains of 179 crew members—all remarkably well preserved thanks to the anaerobic conditions of the shipwreck created by the layers of soft sediment that accumulated over the wreckage.
A new analysis of some of the recovered bones reveals that whether someone is right- or left-handed could affect how their collarbone chemistry changes as they age, according to a new paper published in the journal PLoS ONE. This has implications for our understanding not just of aging, but of bone conditions like fracture risk and osteoarthritis.
As previously reported, the earliest-known reference to the Mary Rose appears in a January 29, 1510, letter ordering the construction of two new ships for the young king: the Mary Rose and her sister ship, dubbed the Peter Pomegranate. Once the newly built ship had launched, Henry VIII wasted no time defying his advisers and declaring war on France in 1512. The Mary Rose served the monarch well through that conflict, as well as during a second war with the French that ran roughly from 1522 through 1525, after which it underwent a substantial overhaul.
Elon Musk turns X’s block button into a “glorified mute button”
X, formerly Twitter, is now letting blocked users see posts made by the people who blocked them.
"We're starting to launch the block function update," X's engineering team wrote yesterday. X previously said that after the change, "If your posts are set to public, accounts you have blocked will be able to view them, but they will not be able to engage (like, reply, repost, etc.)."
To justify the change, X said the block functionality could previously be "used by users to share and hide harmful or private information about those they've blocked." The change will allow people who are blocked "to see if such behavior occurs... allowing for greater transparency," X said.
Nvidia ousts Intel from Dow Jones Index after 25-year run
On Friday, S&P Dow Jones Indices announced that AI chipmaker Nvidia will replace Intel in the Dow Jones Industrial Average, marking a seismic shift in the semiconductor industry and ending Intel's 25-year run on the prestigious stock market index. The change takes effect on November 8.
"The index changes were initiated to ensure a more representative exposure to the semiconductors industry," wrote S&P in a press release.
Intel's stock has dropped 54 percent this year, making it the worst performer on the Dow, and the company now holds a market value of under $100 billion for the first time in three decades, Reuters reported. Analysts expect Intel to post its first annual net loss since 1986.
Sick of supersized EVs? The 2025 Hyundai Kona Electric hits the spot.
If conventional wisdom were to be believed, the car we're reviewing today should not exist. Automakers are only interested in making very big, very expensive electric vehicles, leaving nothing for people with normal-sized budgets and normal-sized needs. While it's true that those oversized EVs are overrepresented among new car launches, they aren't the only game in town. As an alternative, consider the Hyundai Kona Electric, which we last sampled in pre-pandemic times.
In fact, Kona Electric has changed quite a bit since we last drove one. Last year, an all-new model went on sale in North America, and it has carried over unchanged to its model year 2025 version. The range starts at $32,875 for the Kona Electric SE, which makes do with a 133 hp (99 kW) motor driving the front wheels, but the other trims offered—the $36,875 SEL, the $38,275 N Line (tested here), and the $41,050 Limited use a more powerful 201 hp (150 kW) motor. (All four have an identical 188 lb-ft (255 Nm) torque output.)
In terms of size and weight, the Kona Electric really is a refreshing change from EVs that are often approaching three tons. With its rear wing and slightly tweaked front, the N Line is 1.1 inches longer than the other Kona Electrics at 172.6 inches (4,384 mm) long. All Kona Electrics are 71.9 inches (1,826 mm) wide and 62 inches (1,575 mm) tall, with a 104.7-inch (2,659 mm) wheelbase. Curb weight is what counts as featherweight for an EV—3,880 lbs (1,760 kg).
China reveals a new heavy lift rocket that is a clone of SpaceX’s Starship
When Chinese space officials unveiled the design for the country's first super heavy lift rocket nearly a decade ago, it looked like a fairly conventional booster. The rocket was fully expendable, with three stages and solid motors strapped onto its sides.
Since then, the Asian country has been revising the design of this rocket, named Long March 9, in response to the development of reusable rockets by SpaceX. As of two years ago, China had recalibrated the design to have a reusable first stage.
Now, based on information released at a major airshow in Zhuhai, China, the design has morphed again. And this time, the plan for the Long March 9 rocket looks almost exactly like a clone of SpaceX's Starship rocket.
Perplexity will show live US election results despite AI accuracy warnings
On Friday, Perplexity launched an election information hub that relies on data from The Associated Press and Democracy Works to provide live updates and information about the 2024 US general election, which takes place on Tuesday, November 5.
"Starting Tuesday, we'll be offering live updates on elections using data from The Associated Press so you can stay informed on presidential, senate, and house races at both a state and national level," Perplexity wrote in a blog post. The site will pull data from special data sources (called APIs) hosted by the two organizations.
As of Monday, Perplexity's hub currently provides interactive information on voting requirements, poll times, and summaries about ballot measures, candidates, policy positions, and endorsements. Users can ask questions about the information similar to using a chatbot like ChatGPT.
Endangered bees stop Meta’s plan for nuclear-powered AI data center
Plans by Mark Zuckerberg’s Meta to build an AI data center in the US that runs on nuclear power were thwarted in part because a rare species of bee was discovered on land earmarked for the project, according to people familiar with the matter.
Zuckerberg had planned to strike a deal with an existing nuclear power plant operator to provide emissions-free electricity for a new data center supporting his artificial intelligence ambitions.
However, the potential deal faced multiple complications including environmental and regulatory challenges, these people said.
Laptop, smartphone, and game console prices could soar after the election
Tech companies are bracing ahead of the US presidential election, dreading the looming threat of more tariffs that could further restrict the flow of imports from China, no matter which candidate is elected.
Tariffs are a tax placed on imports and are intended to disrupt trade with foreign adversaries. While former President Donald Trump has frequently claimed that China pays for tariffs, in actuality, that tax is paid by US businesses and citizens any time they want to purchase a restricted good from China.
Used as a trade barrier, tariffs can place an economic burden on countries like China, but that burden is really only felt if businesses and consumers avoid importing goods. If companies cannot cost-effectively or practically switch suppliers—as is the case with China, which is a dominant global manufacturing hub in the tech industry—shrinking profit margins can trigger US businesses to spike prices for consumers.
Girls Have a Ball Making Music With Magic Belles
MIT Project Uses Smart Phones to Detect Cataracts
<em>Portal 2</em>'s "Want You Gone" - A Great Fan-Made Music Video
Netflix Confirms Streaming Issues for Some Apple TV Customers
PhotoForge 2, Possibly the Best iPad Photo Editing App Yet
Nerdapalooza Spotlight: I Fight Dragons
Hands-On: The SoundJaw Fixes the iPad 2's Awful Speaker
Video: Cameras Mounted on Fireworks Show Dizzying Point-of-View
Three-Way Headphone Splitter Shaped Like a Tiny Branch
