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A reaction that puzzled scientists for 50 years has now been explained by researchers at Ume University. Rapid structural snapshots captured how graphite transforms into graphite oxide during electrochemical oxidation, revealing intermediate structures that appear and disappear over time. The researchers describe this as a new type of oscillating reaction.

New technology has allowed scientists to create ultra short ion pulses, with a duration of less than 500 picoseconds. This can be used to analyze materials or even make chemical reactions visible in real time.

Dyspraxia, also known as Developmental Coordination Disorder (DCD), can have a bigger impact on adult mathematical performance than previously thought, according to new research.

Thanks to nanoscale devices as small as human cells, researchers can create groundbreaking material properties, leading to smaller, faster, and more energy-efficient electronics. However, to fully unlock the potential of nanotechnology, addressing noise is crucial. A research team has taken a significant step toward unraveling fundamental constraints on noise, paving the way for future nanoelectronics.

Thanks to nanoscale devices as small as human cells, researchers can create groundbreaking material properties, leading to smaller, faster, and more energy-efficient electronics. However, to fully unlock the potential of nanotechnology, addressing noise is crucial. A research team has taken a significant step toward unraveling fundamental constraints on noise, paving the way for future nanoelectronics.

Physicists on the CMS experiment announce the most elaborate mass measurement of a particle that is notoriously difficult to study and has captivated the physics community for decades.

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On balance, will AI help humanity or harm it? AI could revolutionize science, medicine, and technology, and deliver us a world of abundance and better health. Or it could be a disaster, leading to the downfall of democracy, or even our extinction. In Taming Silicon Valley, Gary Marcus, one of the most trusted voices in AI, explains that we still have a choice. And that the decisions we make now about AI will shape our next century. In this short but powerful manifesto, Marcus explains how Big Tech is taking advantage of us, how AI could make things much worse, and, most importantly, what we can do to safeguard our democracy, our society, and our future.

Marcus explains the potential—and potential risks—of AI in the clearest possible terms and how Big Tech has effectively captured policymakers. He begins by laying out what is lacking in current AI, what the greatest risks of AI are, and how Big Tech has been playing both the public and the government, before digging into why the U.S. government has thus far been ineffective at reining in Big Tech. He then offers real tools for readers, including eight suggestions for what a coherent AI policy should look like—from data rights to layered AI oversight to meaningful tax reform—and closes with how ordinary citizens can push for what is so desperately needed.

Taming Silicon Valley is both a primer on how AI has gotten to its problematic present state and a book of activism in the tradition of Abbie Hoffman’s Steal This Book and Thomas Paine’s Common Sense. It is a deeply important book for our perilous historical moment that every concerned citizen must read.

Gary Marcus is a leading voice in artificial intelligence, well known for his challenges to contemporary AI. He is a scientist and best-selling author and was founder and CEO of Geometric.AI, a machine learning company acquired by Uber. A Professor Emeritus at NYU, he is the author of five previous books, including the bestseller Guitar Zero, Kluge (one of The Economist’s eight best books on the brain and consciousness), and Rebooting AI: Building Artificial Intelligence We Can Trust (with Ernest Davis), one of Forbes’s seven must-read books on AI.

“Move fast and break things.” —Mark Zuckerberg, 2012

“We didn’t take a broad enough view of our responsibility.” —Mark Zuckerberg, speaking to the U.S. Senate, 2018

“Generative AI systems have proven themselves again and again to be indifferent to the difference between truth and bullshit. Generative models are, borrowing a phrase from the military, ‘frequently wrong, and never in doubt.’ The Star Trek computer could be counted on to gives sound answers to sensible questions; Generative AI is a crapshoot. Worse, it is right often enough to lull us into complacency, even as mistakes invariably slip through; hardly anyone treats it with the skepticism it deserves. Something with reliability of the Star Trek computer could be world-changing. What we have now is a mess, seductive but unreliable. And too few people are willing to admit that dirty truth.” —Gary Marcus

Shermer and Marcus discuss:

• The AI we have now and the AI we should want
• AI, AGI, Generative AI, ChatGPT
• What’s the problem to be solved?
• 12 biggest threats of Generative AI
• The morality of Silicon Valley
• How Silicon Valley manipulates public opinion
• How Silicon Valley manipulates government policy
• Data rights
• Privacy
• Transparency
• Liability
• Independent oversight
• Incentives good and bad
• Private vs. Government regulation of AI
• International AI governance.

If you enjoy the podcast, please show your support by making a $5 or $10 monthly donation.

Understanding the relationship between plasticity of muddy soil and earth pressure can be crucial to maintaining tunnel stability and predicting ground behavior during earth pressure balance (EPB) shield tunnelling, a common underground excavation method. Researchers developed small-scale model experimentation combined with moving particle simulation-based computer-aided engineering analysis that reliably predicted soil's plasticity and its correlating factors without having to deal with the cost and time of on-ground field analysis.

Watching for changes in Mars' orbit over time could be new way to detect passing dark matter, according to researchers.

A key step toward reusing CO2 to make sustainable fuels is chaining carbon atoms together, and an artificial photosynthesis system can bind two of them into hydrocarbons with field-leading performance.

Researchers developed an artificial motor at the supramolecular level that can develop impressive power. This wind-up motor is a tiny ribbon made of special molecules. When energy is applied, this ribbon aligns itself, moves like a small fin and can thus push objects. The energy for this comes from a chemical fuel.

Researchers developed an artificial motor at the supramolecular level that can develop impressive power. This wind-up motor is a tiny ribbon made of special molecules. When energy is applied, this ribbon aligns itself, moves like a small fin and can thus push objects. The energy for this comes from a chemical fuel.

With the help of NASA's Hubble Space Telescope, an international team of scientists has found more black holes in the early universe than has previously been reported. The new result can help scientists understand how supermassive black holes were created.

Cultural values and traditions differ across the globe, but large language models (LLMs), used in text-generating programs such as ChatGPT, have a tendency to reflect values from English-speaking and Protestant European countries. A research team believes there is an easy way to solve that problem.

In a new paper, physicists argue that close observations of merging black hole pairs may unveil information about potential new particles.

In a new paper, physicists argue that close observations of merging black hole pairs may unveil information about potential new particles.

Van Gogh's brushstrokes in 'The Starry Night' create an illusion of sky movement so convincing it led researchers to wonder how closely it aligns with the physics of real skies. Marine sciences and fluid dynamics specialists analyzed the painting to uncover what they call the hidden turbulence in the artwork. They used brushstrokes to examine the shape, energy, and scaling of atmospheric characteristics of the otherwise invisible atmosphere and used the relative brightness of the varying paint colors as a stand-in for the kinetic energy of physical movement.

Billions of dollars of observatory spacecraft orbit around Earth or in the same orbit as our planet. When something wears out or goes wrong, it would be good to be able to fix those missions “in situ”. So far, only the Hubble Space Telescope (HST) has enjoyed regular visits for servicing. What if we could work on other telescopes “on orbit”? Such “fixit” missions to other facilities are the subject of a new NASA paper investigating optimal orbits and trajectories for making service calls on telescopes far beyond Earth.

Some of the most productive orbiting telescopes operate at the Sun-Earth Lagrange points L1 and L2. Currently, those positions afford us some very incredible science. What they can’t afford is easy access for repairs and servicing. That limits the expected lifetime of facilities such as JWST to about 10-15 years. In the future, more missions will be deployed a Lagrange points. These include the Nancy Grace Roman Telescope, ESA’s PLATO and ARIEL missions, and the Large Ultraviolet Optical Infrared Surveyor (LUVOIR).

Artist’s impression of the Nancy Grace Roman Space Telescope, named after NASA’s first Chief of Astronomy. This spacecraft will orbit at SEL2, far from Earth. Credits: NASA

These observatories need propellants for attitude thrusters to help them stay ‘in place’ during their observations. There’s only so much “gas” you can send along with these observatories. In addition, components wear out, as they did with HST. So, people are looking at ways to extend their lifetimes through servicing missions. If failing components can be replaced and propellant delivered, the lifetimes of these observatories should be extended quite a bit, giving astronomers more bang for the observational buck.

Planning Future Spacecraft Servicing Missions

Researchers at the Satellite Servicing Capability Office (SSCO) at the Goddard Space Flight Center (GSFC) investigated the possibilities for servicing missions to distant space telescopes. In a recently released paper, they focus on the feasibility of on-orbit refueling missions for space telescopes orbiting at Sun-Earth Lagrange 2 (SEL2).

There are many challenges. For one thing, present-day launch technologies are (at this writing) inadequate to do that kind of mission at such distances. Clearly, the technology has to advance for servicing visits to take place. In addition, it’s important to remember that current telescopes, such as Gaia and JWST, weren’t designed for such access. However, future telescopes can be fitted with servicing ports, etc. to enable servicing. Finally, there are the challenges of actually getting the servicing missions to the observatories.

Illustration of OSAM-1 (bottom) grappling Landsat 7. This servicing mission concept was discontinued by NASA, but remains a good example of what’s needed to perform repairs and refueling to orbiting spacecraft. Credits: NASA

The Goddard team focused on this final issue by computing models of various launch and orbital solutions for such missions. Not only did they take into account the launch trajectories themselves, but also Sun-Earth-Lagrange point dynamics, plus the relative positions of observatories at SEL2. In addition, the team considered the stability of the observatories during and after rendezvous and attachment. All of these factors count when planning whether or not a servicing vehicle can be launched at a reasonable cost to extend the lifetime of the observatory enough to make the effort worth the time and expense.

Getting a Spacecraft Refuelling Mission Underway

The team created models for a theoretical mission for on-orbit fuelling at SEL2. That’s where JWST and Gaia are sitting, for example, along with WMAP, Planck, and others. The paper examines robotic refueling missions out to SEL2 for modeling purposes.

To do that, however, there must be an optimal trajectory for the robotic spacecraft to take out to SEL2. They need to be able to perform autonomous navigation to the correct point in space. Once at the target observatory, the refueling robot would then need to make a careful approach for its docking maneuvers. That requires on-orbit assessment of the target’s motion in space with respect to the Sun as well as its position in its SEL2 orbit. Docking itself can affect the observatory’s position and motion and the robot needs to take that into account, as well. The idea is to keep the observatory in the same position after docking.

However, the big question is: how do we get it out there inexpensively, fast, and safe?

The Goddard team primarily investigated the best and most efficient trajectories to get to SEL2. In particular, they looked at the best approaches to get to the Gaia spacecraft, which will run out of its propellant sometime in the next year. They also examined JWST as a possible target for such a mission. If such a mission was possible today, those observatories would gain years of “point and shoot” access to the Universe.

How to Get There

In their paper, the team looks at two approaches to the SEL2 refueling mission. One is a direct launch trajectory from Earth and the other is a spacecraft leaving from a geostationary transfer orbit (GTO). They assumed that the point of the mission was the fastest possible restoration of telescope operation. That dictates the shortest and safest possible trajectory along which the spacecraft can maintain constant thrust.

The Goddard team created a “forward design” approach for computing low-energy and low-thrust transfers from an Earth departure orbit to a space telescope orbiting the SEL2 point. Then they did the same for a servicing spacecraft leaving from a point in geostationary space. Essentially, either an Earth-departure or GTO-centric departure will work. Once the robotic servicing mission leaves Earth orbit, it travels at low thrust during a spiraling transit to SEL2. Once there, it does a rendezvous with the target, matches its motion in space, and then “locks on” to perform its delivery mission.

It’s important to remember that a launch from Earth or GTO is part of several solutions to SEL2 servicing missions. The team’s analysis resulted in a simplified process of generating possible orbits and trajectories for such activities. You can read the full text of their detailed analysis of the different trajectory solutions at the link below.

For More Information

Mission Design for Space Telescope Servicing at Sun-Earth L2
JWST Home Page
Gaia Telescope

The post There Could be a Way to Fix Spacecraft at L2, Like Webb and Gaia appeared first on Universe Today.

Maternity services need to educate parents-to-be on how pregnancy will affect their brain - their life could depend on it, says Helen Thomson

Echolocating bats can more easily find and pollinate long-stemmed flowers that stand out from the surrounding foliage, which may be why this floral trait evolved