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Submission Summary: 0 pending, 20 declined, 12 accepted (32 total, 37.50% accepted)

Submission + - Surprisingly, some Dyson spheres and ringworlds can be stable (phys.org) 1

Required Snark writes: In the realm of science fiction, Dyson spheres and ringworlds have been staples for decades. But it is well known that the simplest designs are unstable against gravitational forces and would thus be torn apart. Now a scientist from Scotland UK, Dr. Colin McInnes, has shown that certain configurations of these objects near a two-mass system can be stable against such fractures.

For the restricted ring, McInnes found that there are seven equilibrium points in the orbital plane of the dual masses, on which, if the ring's center were placed, it would stay and not experience stresses, akin to the three stable Lagrange points where a small mass can reside permanently for the two-body problem.

McInnes restricted this research to a planar ring (in the plane of the circularly orbiting masses) but says it can be shown that a vertical ring, normal to the plane, can also generate equilibria. For example, one such point is a vertical ring with its center at the midpoint between the two masses.

Submission + - Thailand shuts power to Myanmar's scam hub (youtube.com) 1

Required Snark writes: From the South China Morning Post.

Thai authorities have cut off internet, power and fuel along the Thailand and Myanmar border in a bid to thwart the operation of scam centres there. The move on February 5, 2025, came amid growing pressure for Thailand to do more to help clamp down on the illegal compounds that have ensnared vast numbers of people from many jurisdictions. The Thai Provincial Electricity Authority disconnected power supplies at five points along the northern border, including Myawaddy in Myanmar’s Shan state.

The scam centers have massive power backup and may also be able to tap power from Laos. Hundreds of thousands of people have been trafficked to work at the centers.

Submission + - NASA's commercial spacesuit program has cancellation

Required Snark writes: Ars Technica reports that one of the two companies selected to build the next generation of NASA space suites, one of them, Collins Aerospace, has decided to withdraw from it's contract.

The new spacesuit contracts started two years ago, with Collins selected to make in orbit gear, and Axiom producing lunar and Artemis suits. Ongoing problems with current suits have already reduced the planned number of spacewalks at the ISS.

NASA may choose to continue with just the Axiom contact, or it may reopen bidding. One potential bidder is SpaceX, which has already designed a basic spacesuit to support the private Polaris Dawn mission.

Submission + - RISC V CPU designed by AI (tomshardware.com)

Required Snark writes: A group of Chinese scientists has published a paper titled "Pushing the Limits of Machine Design: Automated CPU Design with AI." The paper details the researchers' work in designing a new industrial-scale RISC-V CPU in under 5 hours. It is claimed this AI-automated feat was about 1000x faster than a human team could have finished a comparable CPU design.

Training consisted of observing a series of CPU inputs and outputs. The scientists generated a Binary Speculation Diagram (BSD) from this I/O and leveraged principles of Monte Carlo-based expansion and Boolean functions to hone the accuracy and efficiency of the AI-based CPU design. Thus the CPU design was formed "from only external input-output observations instead of formal program code," explains the scientists. The generated CPU "discovered the von Neumann architecture from scratch."

Submission + - Despite statements to the contrary, Acer is still shipping PCs to Russia

Required Snark writes: Acer Electronics is selling computers in Russia even though they claimed they would abide by the Taiwanese government's commitment to the international embargo on western technology. The sales are through their Swiss subsidiary Acer Sales International SA. This subterfuge means Acer's position is nominally true even while they are breaking the embargo. Neither Russian, Swiss or Taiwanese government officials would comment on the report.

Submission + - The End of the A380 Era

Required Snark writes: It's the end of the line for the biggest passenger jet ever built: the A380 is going to cease production. According to CNN:

The European plane maker said Thursday that it will stop delivering A380s in 2021 after its key customer, Dubai-based airline Emirates, slashed its orders for the huge jetliner.

"We have no substantial A380 backlog and hence no basis to sustain production, despite all our sales efforts with other airlines in recent years," Airbus CEO Tom Enders said in a company statement.

The company has delivered 234 of the superjumbos to date, less than a quarter of the 1,200 it predicted it would sell when it first introduced the double-decker aircraft. Its plans were undermined by airlines shifting their interest to lighter, more fuel efficient passenger jets that have reduced the need to ferry passengers between the big hubs.

Submission + - Japanese X-ray Satellite Declared a Complete Loss (scientificamerican.com)

Required Snark writes: The Japanese space agency JAXA has announced it's recently launched X-Ray observation satellite Hitomi has been destroyed. After a successful launch on February 17th, contact was lost on March 28th. Only three days of observations were collected, out of a 10 year expected life span.

A preliminary inquiry points to multiple failures of design, hardware and software causing the destruction of the satellite. After launch it was discovered that the star tracker stabilization didn't work in a low magnetic flux area over the South Atlantic. When the backup gyroscopic spin stabilization took control the the spin increased instead of stopping. An internal magnetic limit feature in the gyroscope failed, making the spin worse.

Finally a thruster based control started, but because of a software failure the spin increased further. Finally the solar panels broke off, leaving the satellite without a long term power supply. It seems that untested software had been uploaded for thrust control just before the breakup.

This is a major loss for astronomical research. Two previous attempts by Japan to launch a high resolution X-ray calorimeter had failed, and the next planned sensor of this type is not scheduled until 2028 by the ESA. Just building a replacement unit would take 3 to 5 years and cost $50 million, without the cost of a satellite or launch.

Submission + - FBI and DOJ Drop Case Against Chinese-America Physicist

Required Snark writes: In yet another spectacular failure, the FBI and Department of Justice have withdrawn their prosecution (or more accurately persecution) Dr. Xi Xiaoxing, former head of the Physics Department at Temple University, according to the New York Times. He was accused of attempting to transfer technology about a "pocket heater" to China. It is used in superconducting research.

The case fell apart because the evidence that the FBI had was not about a pocket heater. "In a sworn affidavit, one engineer, Ward S. Ruby, said he was uniquely qualified to identify a pocket heater. 'I am very familiar with this device, as I was one of the co-inventors,' he said."

Apparently nobody in the FBI or DOJ bothered to verify that the information referred to the device in question: "Dr. Xi’s lawyer, Peter Zeidenberg, said that despite the complexity, it appeared that the government never consulted with experts before taking the case to a grand jury. As a result, prosecutors misconstrued the evidence, he said."

Dr Xi was forced to step down from his position as the head of the department during the investigation. He was unable to work on his ongoing experiments and was branded a spy. What are the odds that anyone at the FBI or DOJ will face any personal or professional repercussions? If recent history is any guide they will not even issue a statement. When the case was withdrawn the option to refile was retained, a blatant attempt to save face and deny responsibility.

Submission + - Gaming computers offer huge, untapped energy savings potential

Required Snark writes: According to Phys.org, a study by Evan Mills at Berkeley Lab shows that "gamers can achieve energy savings of more than 75 percent by changing some settings and swapping out some components, while also improving reliability and performance" because "your average gaming computer is like three refrigerators".

Gaming computers represent only 2.5 percent of the global installed personal computer (PC) base but account for 20 percent of the energy use. Mills estimated that gaming computers consumed 75 TWh of electricity globally in 2012, or $10 billion, and projects that will double by 2020 given current sales rates and without efficiency improvements. Potential estimated savings of $18 billion per year globally by 2020, or 120 terawatt hours (TWh) are possible.

Mills started the site GreeningtheBeast.org. The full paper PDF can be found here.

Submission + - California Legislation May Allow FIrst Responders to Shoot Down Drones

Required Snark writes: During the recent North Fire that burned vehicles on I-15 in California, firefighters had to suspend aerial operations because of the presence of drone aircraft according to CNN

Five such "unmanned aircraft systems" prevented California firefighters from dispatching helicopters with water buckets for up to 20 minutes over a wildfire that roared Friday onto a Los Angeles area freeway that leads to Las Vegas.

Helicopters couldn't drop water because five drones hovered over the blaze, creating hazards in smoky winds for a deadly midair disaster, officials said.

In response, legislation has been introduced that would allow first responders to disable drones in emergency situations. A second bill would allow jail time and fines for drone users that interfere with firefighting efforts.

Senate Bill 168, introduced by Gatto and Sen. Ted Gaines, R-El Dorado, would grant “immunity to any emergency responder who damages an unmanned aircraft in the course of firefighting, air ambulance, or search-and-rescue operations.”

Los Angeles County fire Inspector David Dantic declined to comment on the specific legislation, but said his agency’s aircraft cannot operate safely if a drone is in the same airspace.

Gatto and Gaines also teamed up on companion legislation: SB 167, which would increase fines and introduce the possibility of jail time for drone use that interferes with firefighting efforts.

Submission + - Proposed Space Telescope Uses Huge Opaque Disk to Surpass Hubble (gizmag.com)

Required Snark writes: NASA has funded a study of a geo-sychrounous orbit telescope that uses a half mile diameter opaque disk to provide images with 1000 times the resolution of the Hubble. It uses diffraction at the edge of the disk to focus light, resulting in a very high quality image. It's named the Aragoscope, after the scientist Francois Arago, who first noticed how a disk effects light waves.

When deployed the Aragoscope will consist of an opaque disk a half mile in diameter parked in geostationary orbit behind which is an orbiting telescope keeping station some tens to hundreds of miles behind that collects the light at the focal point and rectifies it into a high-resolution image.

"The opaque disk of the Aragoscope works in a similar way to a basic lens," says CU-Boulder doctoral student and team member Anthony Harness. "The light diffracted around the edge of the circular disk travels the same path length to the center and comes into focus as an image." He added that, since image resolution increases with telescope diameter, being able to launch such a large, yet lightweight disk would allow astronomers to achieve higher-resolution images than with smaller, traditional space telescopes.


Submission + - Hunters Shoot Down Drone of Animal Rights Group (thetandd.com)

Required Snark writes: A remote control drone operated by an animal rights group was shot down in South Carolina by a group of thwarted hunters.
Steve Hindi, the group president said "his group was preparing to launch its Mikrokopter drone to video what he called a live pigeon shoot on Sunday when law enforcement officers and an attorney claiming to represent the privately-owned plantation near Ehrhardt tried to stop the aircraft from flying." After the shoot was halted, the drone was launched anyway, and at this point it was shot down. "Seconds after it hit the air, numerous shots rang out," Hindi said in the release. "As an act of revenge for us shutting down the pigeon slaughter, they had shot down our copter." "It is important to note how dangerous this was, as they were shooting toward and into a well-travelled highway," Hindi stated in the release.

Submission + - Sea water can cause uranium polution from fuel rod (ucdavis.edu)

Required Snark writes: UC Davis researchers have found a mechanism where the sodium in sea water can cause uranium nano-particles to be released from nuclear reactor fuel rods. Normally the uranium oxide compounds composing the rods are very resistant to leaching into water. This could have serious consequences for the Fukushima disaster, since sea water was used for emergency cooling.

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