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Deep inside what we perceive as solid matter, the landscape is anything but stationary. The interior of the building blocks of the atom's nucleus -- particles called hadrons that most of us would recognize as protons and neutrons -- are made up of a seething mixture of interacting quarks and gluons, known collectively as partons. The HadStruc collaboration has now come together to map out these partons and disentangle how they interact to form hadrons.

A new type of OLED (organic light emitting diode) could replace bulky night vision goggles with lightweight glasses, making them cheaper and more practical for prolonged use, according to researchers.

A new article describes a fingernail-sized machine that can twist thin materials at will, replacing the need to fabricate twisted devices one by one.

Americans are famously fond of their guns. So it should come as no surprise that a team of NASA scientists has devised a way to “shoot” a modified type of sensor into the soil of an otherworldly body and determine what it is made out of. That is precisely what Sang Choi and Robert Moses from NASA’s Langley Research Center did, though their bullets are miniaturized spectrometers rather than hollow metal casings. 

First, let’s look at the miniaturized spectrometers. Spectrometers have been a workhorse of space exploration for decades. They analyze everything from the surface of Enceladus to stars. However, they almost all use a type of spectroscopy known as Fraunhofer diffraction. Drs. Choi and Moses decided to use a different physical phenomenon in their invention, known as Fresnel’s diffraction.

In Fresnel diffraction, a spectral graph becomes very clear at much smaller distances than those created by Fraunhofer diffraction. Since the necessary distance between a “grating” and the sensor required by a spectrometer using Fraunhofer diffraction is one of the system’s design constraints, most spectrometers in use today are prohibitively large.

Fraser discusses the importance of the lunar south pole – which includes many permanently shadowed craters

Fresnel diffraction, however, allows for the creation of much smaller spectrometers. In the case of Dr. Choi and Moses’s invention, all of the necessary power, signaling, and analysis electronics can fit into a small cylindrical tube only slightly larger than a traditional bullet.

That was likely where the idea for shooting these sensors into the ground came from. If the “micro-spectrometers” were surrounded by regolith, whether the Moon, an asteroid’s, or Mars’, it would allow quick analysis of the composition of the soil wherever it is embedded. Since these sensors are easily deployed, if multiple of them were spread throughout a lunar crater, a single astronaut (or rover) could characterize the soil makeup of an entire area without hand-digging a space for each sample area.

This is where the “gun” comes in—a rover, or even an astronaut, could be fitted with a tube that “fires” the cylindrical micro-spectrometer into the ground, embedding it where it can do the best science. A single rover or astronaut could then distribute enough of these to collect data on an entire area, such as the permanently shadowed regions of a lunar crater.

Image of a prototype micro-spectrometer
Credit – Choi and Moses

Such a system could also be used on asteroids from an orbiter or even Mars. It could use telemetry back to a central connection point—potentially also carried by the astronaut or rover. Unfortunately, at least in the current iteration, it couldn’t be reused, though that could change in new designs.

This invention, which NASA has patented, could also be used on Earth if a mining or petroleum company wants to quickly sample an area’s geological makeup. But it is also useful in space—so much so that we might someday find astronauts shooting what look to be bullets but are actually miniaturized sensors directly into the ground.

Learn More:
Sang H Choi – Lunar, Mars, and Asteroid Exploration for Space Resources
Choi & Moses – Micro-Spectrometer for Resource Mapping in Extreme Environments
UT – The Darkest Parts of the Moon are Revealed with NASA’s New Camera
UT – Absorption Spectroscopy

Lead Image:
Depiction of the “bullets” being deployed in a lunar crater.
Credit – NASA

The post Could You Find What A Lunar Crater Is Made Of By Shooting It? appeared first on Universe Today.

Is it time for space lasers yet? Almost.

As time passes, ideas that were once confined to the realm of science fiction become more realistic. It’s true of things like using robots to explore other worlds. Space lasers are a well-used element in science fiction, and we’re approaching the time when they could become a reality.

Where would we put them, and what could we use them for?

In science fiction, lasers are predominantly used as powerful weapons. While some countries have investigated the idea of using lasers as space weapons, an international treaty limits their use.

A more realistic use for lasers is for deflecting incoming asteroids or as propulsion systems for spacecraft. In a new paper, a researcher examines where a giant laser array could be positioned in space to be of most use to humanity while at the same time minimizing risk.

The research is “Minimum Safe Distances for DE-STAR Space Lasers.” The paper is in pre-print, and Adam Hibberd from the Initiative for Interstellar Studies in London, UK, is the sole author.

While space lasers could also be used to utilize resources or in satellite laser ranging systems to control space traffic, Hibberd’s focus is on using them to protect Earth from impacts.

DE-STAR stands for Directed Energy Systems for Targeting of Asteroids and exploRation. Of all the space laser ideas that have been discussed, DE-STAR is probably the most well-studied and developed. It would consist of a modular phased array of lasers powered by solar cells. It could heat the surface of potentially hazardous objects (PHO) to approximately 3,000 Kelvin. That’s hot enough to melt all known constituents of PHOs. DE-STAR could also be used to propel spacecraft.

The idea originated in 2013 when a group of researchers published a paper titled “DE-STAR: Phased-Array Laser Technology for Planetary Defense and Other Scientific Purposes.” In their paper, they outlined the idea for DE-STAR, a stand-off laser array. In 2016, some of the same authors published another paper titled “Directed Energy Missions for Planetary Defense.” It expanded on DE-STAR and added DE-STARLITE, a stand-on system that would be sent to the vicinity of an approaching object to ward it off with lasers.

This artist’s illustration shows DE-STARLITE firing its lasers at a hazardous object. Image Credit: Lubin et al. 2016.

In either case, the system would be based on the Sun’s energy. “DE-STAR is a square modular design which exploits the energy created by banks of solar cells in space to generate and amplify the power of a laser beam,” Hibberd explains in his new paper. In literature, DE-STAR is typically referred to as DE-STAR n, where n is usually between 0 and 4 and denotes the size of the bank of lasers. The larger the array, the more powerful it is. The more powerful DE-STAR is, the more effective it will be at deflecting asteroids from greater distances.

While the merit of this idea is immediately clear, the problems follow soon after. A bank of powerful space lasers is every supervillain’s dream. Its destructive power could be immense. “With a DE-STAR 4
structure (10 km × 10 km square) capable of generating a laser beam on the order of tens of gigawatts,
clearly, there is the potential for such an asset to be deployed as a weapon by targeting locations on Earth,” Hibberd writes.

How can this risk be mitigated so that the system can be used to protect Earth rather than as a weapon?

The simple solution is to not deploy them in Earth’s orbit. The lasers lose energy with range, so they could be deployed at distances where they pose no threat. “Results indicate that given they should lie 1 au from
the Sun, there are feasible locations for DE-STAR 0-2 arrays where there is no danger to Earth,” Hibberd writes.

This table from the paper shows the specs adopted in this paper for different-sized DE-STAR arrays. The clip ratio affects beam quality, energy efficiency, how well it propagates through space, and how well it handles heat generation. Smaller is generally better, and 0.9 is the ratio adopted by other researchers. Optimizing the clip ratio is an important part of designing an effective array. Image Credit: Hibberd 2024.

Of course, the more lasers there are in the array, the greater the safe minimum distance.

For DE-STAR 4 or even 5, that distance wouldn’t be enough. Instead, these lasers would need to be much further away or at positions in the Solar System with no direct line of sight to Earth. These systems would need to correct their positions regularly with an on-board propulsion system “or preferably using push-back from the laser itself,” Hibberd explains.

The minimum safe distance also changes depending on the wavelength of the DE-STAR system. Hibberd defines minimum safe distance as a single laser with a maximum intensity on Earth’s surface of 100 Wm-2. “Or on the order 10 % of the Solar Constant at Earth (1 au from the Sun),” Hibberd writes. For an infrared system, the minimum safe distance is just beyond geosynchronous Earth orbit (GEO). At the more powerful end of the scale, a UV laser would need to be beyond cis-lunar space.

This figure from the research shows the Dependence of the Minimum Safe Distance of any Unphased DE-STAR Array with the Wavelength of the Laser. Image Credit: Hibberd 2024.

There’s another factor to consider. Since DE-STAR gets its energy from the Sun, its power decreases the further away from the Sun it is. “This reduction is a consequence of the decrease in solar flux intensity on the photovoltaic cells, where an inverse square law is followed,” Hibberd explains.

This figure shows how the laser’s power diminishes with distance from the Sun for four different array sizes. “We find that a DE-STAR n at 90 au from the Sun is approximately equivalent to a DE-STAR n-1 at 10 au and a DE-STAR n-2 at 1 au,” Hibberd writes. Image Credit: Hibberd 2024.

For DE-STAR 1 and 2 Arrays, the minimum safe distances are not that great. Hibberd points out that for a DE-STAR 2 Array, Sun/Earth Lagrange 4 and 5 points would be suitable and require no propulsion. L4 and L5 are about 400,000 km from Earth.

These figures show the minimum safe distance for DE-STAR 1 and 2 Arrays by wavelength. Image Credit: Hibberd 2024.

However, as the arrays become larger, the minimum safe distance quickly increases. Conversely, the available solar energy decreases.

A DE-STAR 3 would have to be placed somewhere beyond the asteroid belt. If it were ultraviolet, it would have to be beyond Jupiter.

A DE-STAR 4 phased array would have to be much further away. It would have to be about 30 ? 40 au away, and even further for an ultraviolet system, about 70 au from the Sun.

These figures show the minimum safe distance for DE-STAR 3 and 4 Arrays by wavelength. Image Credit: Hibberd 2024.

The tables above assume a direct line of sight to Earth. But there are locations where there is no direct line, and they could be used as locations for powerful arrays. Hibberd explains that the Earth/Moon Lagrange 2 point and the Sun/Earth Lagrange 3 point both lack direct lines of sight but, unfortunately, are unstable. “In both cases, the instability of these points will result in the DE-STAR wandering away and potentially becoming visible from Earth, so an on-board propulsion would be needed to prevent this,” Hibberd writes. It’s possible that an array could be built that is physically prevented from pointing at Earth, but the author doesn’t tackle that aspect of the problem.

Sun-Earth Lagrange Points. Credit: Xander89/Wikimedia Commons

Nobody’s building a DE-STAR phased array, but that doesn’t mean it’s too soon to think about it. This type of technology is on the horizon, and it’s difficult to predict which nation or nations might be the first to build one. Treaties are in place to prevent the weaponization of space, but not everybody signed them. Some nations are known to sign treaties and then break them, in any case. Also, an argument could be made that this isn’t a weapon.

It likely won’t be long before serious talk about such a system begins to surface in wider public discussions. That will surely generate a lot of political difficulty and wrangling as nations argue over what constitutes a weapon and what doesn’t.

If civilization is to survive, we will eventually need a way to protect the entire globe from asteroid strikes, whether it’s phased laser arrays or some other system.

The post There are Plenty of Uses for Powerful Lasers in Space. But Where Should We Put Them? appeared first on Universe Today.

Even though the strange behaviour we observe in the quantum realm isn’t part of our daily lives, simulations suggest it is likely our reality could be one of the many worlds in a quantum multiverse

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.

https://traffic.libsyn.com/secure/sciencesalon/mss469_Gary_Marcus_2024_09_17.mp3 Download MP3

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.