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Experiments in a state-of-the-art wave tank suggest we have underestimated the potential size and power of rogue waves and the risk they pose to offshore infrastructure

Simple words like "force" and "particle" can mislead us as to what reality is actually like. Physicist Matt Strassler unpacks how to see things more clearly

An artificial intelligence model that can identify the calls of eight whale species is helping researchers track the elusive whale behind a perplexing sound in the Pacific

Today’s Jesus and Mo strip, called “laugh 2” is a resurrection, so to speak, from 2009. The artist is apparently still on holiday, but I doubt you’ve seen this one.  I wonder if religious bookstores have “humor” sections.  I know there are funny books about Jews, like books about Jewish jokes and, of course, Leo Rosten’s incomparable The Joys of Yiddish. (The latter book was given to me by my advisor when I graduated from college, along with Crow and Kimura’s Theoretical Population Genetics; I was told that these two books were all I needed to equip me for a career in population genetics. The field is, of course, heavily Jewish.)  But I digress.  Here the barmaid is laughing:

The New Zealand radio station “The Platform” had me on yesterday for a 25-minute segment on the country’s attempt to teach Mātauranga Māori (Māori “ways of knowing”) as coequal with modern science.  The host, Michael Laws, did a pretty good job, though he thought I was in New York,. Click on the screenshot below to listen to my thoughts and Laws’s questions. As usual, I can’t stand to hear my voice, which seems unduly nasal, and the sound quality on my end isn’t so great because I was at home using my landline (first time in years). Finally, my cellphone rang at the beginning of the interview because I forgot to turn it off.

That said, as I recall I said what I needed to say, and I thought the bit at the end about racism was appropriate.

As you might guess “The Platform” is a bit heterodox and goes against the local Zeitgeist, so you could think of it as New Zealand’s radio equivalent of “The Free Press”. I may have been preaching to the choir, but right now that’s the only way you can even be heard in New Zealand.

Click to listen (there may be a slight delay after you click before you get to the site):

Attention-deficit/hyperactivity disorder (ADHD) is one of the most commonly diagnosed neurodevelopment disorders and seems to be on the rise, in both children and adults. The diagnosis in children requires having various symptoms of attention deficit or hyperactivity which is functionally impairing with onset by age 12. Recognition of the disorder actually goes back farther than you might think – the observation that […]

The post Why Is ADHD On The Rise first appeared on Science-Based Medicine.

The second-closest planet to the sun is more geologically active than we thought and could have more than 17,000 venusquakes a year

Located in the constellation Ursa Major, roughly 300 light-years from Earth, is the Sun-like star HD 118203 (Liesma). In 2006, astronomers detected an exoplanet (HD 118203 b) similar in size and twice as massive as Jupiter that orbits very closely to Liesma (7% of the distance between Earth and the Sun), making it a “Hot Jupiter.” In a recent study, an international team of astronomers announced the detection of a second exoplanet in this system: a Super Jupiter with a wide orbit around its star. In short, they discovered a “Cold Super-Jupiter” in the outskirts of this system.

Gracjan Maciejewski – an Associate Professor with the Institute of Astronomy at Nicolaus Copernicus University (NCU) in Torun, Poland – led the study, which recently appeared in the journal Astronomy & Astrophysics. He was joined by researchers from the Department of Astronomy and Astrophysics and the Center for Exoplanets and Habitable Worlds at Pennsylvania State University (PSU), the Instituto de Astrofísica de Canarias, the Agencia Espacial Española (AEE), the Instituto de Astrofísica de Andalucía (IAA-CSIC), and the Center for Astrophysical Surveys at the National Center for Supercomputing Applications (NCSA).

According to their study, the planet (HD 118203 c) is up to eleven times the mass of Jupiter and orbits its parent star at a distance of 6 AU (six times the distance between Earth and the Sun) with a period of 14 years. Astronomers discovered the parent star in 1891 using the Draper telescope, now located in the NCU Institute of Astronomy in Piwnice, near Torun. Liesma is a G-type yellow dwarf (like our Sun), but 20% more massive and twice as large. Astronomers estimate that the star and its entire planetary system are slightly older than the Sun (an estimated 5 billion years).

Henry Draper’s Astrograph (1891), donated by Harvard College Observatory in 1947. Credit: Andrzej Romanski

While astronomers have known that a fairly massive planet orbits HD 118203 for nearly twenty years, it was only in 2006 that it was confirmed using Radial Velocity (Doppler Spectroscopy) measurements. However, these measurements indicated a linear trend that indicated there may be a companion planet with a wider orbit. The presence of another planet would indicate that the system has a hierarchical orbital architecture, which could help astronomers learn more about the origins of hot Jupiters. As Prof. Andrzej Niedzielski, a co-author of the study, explained in an NCU news story:

“Doppler observations, however, indicated that this was not the end of the story, that there might be another planet out there. Therefore, we immediately included this system in our observational programs. At first, as part of the Torun-Pennsylvania exoplanet research program, conducted in collaboration with Professor Aleksander Wolszczan, we tracked the object with one of the largest optical instruments on Earth, the nine-metre Hobby-Eberly Telescope in Texas.”

The results were so promising that the international team continued observing the star using the Telescopio Nazionale Galileo (TNG) at the Roque de los Muchachos Observatory. But first, it was necessary to rule out the possibility that more planets were hiding in the system. “I analyzed photometric observations obtained with the Transiting Exoplanet Survey Satellite space telescope, showing that there were no other planets around HD 118203 larger than twice the size of Earth, and therefore not massive enough to be relevant for studying the dynamics of the system,” said Julia Sierzputowska – an astronomy student and co-author of the study.

By 2023, the team obtained solid data of a Super Jupiter with a wide orbit, demonstrating that HD 118203 was a hierarchical planetary system. Said Prof. Maciejewski:

“Patience pays off. The new observations collected in March 2023 proved crucial in determining the planet’s orbital parameters. Moreover, because it takes a planet several years to orbit its star, we were able to combine our Doppler observations with available astrometric measurements to unambiguously determine its mass. This allowed us to build a complete model of this planetary system and study its dynamical behaviour.”

Astronomers from the NCU have discovered a new planet in the constellation Ursa Major. Credit: Andrzej Romanski

The configuration is peculiar, where one planet orbits closely with its star (forming a pair) while a second orbits them wide enough to form another pair with the first one. While both planets are massive and have rather elongated orbits, their mutual gravitational influence does not destabilize the system over the course of eons. According to their study, this is due to the effects of General Relativity, which prevents the planets from constantly changing the shape of their orbits and orientation in space.

This makes HD 118203 one of only a handful of hierarchical systems known to astronomers, which will help address theories of how massive planets form. This will, in turn, allow astronomers to learn more about the formation and evolution of the gas giants in our Solar System – Jupiter, Saturn, Uranus, and Neptune. The international team also plans to keep gathering data on this system in the hopes of finding additional exoplanets.

Further Reading: NCU News, Astronomy & Astrophysics

The post Astronomers Have Found a Star with a Hot Jupiter and a Cold Super Jupiter in Orbit appeared first on Universe Today.

Some lizards dive into streams to escape predators, and a specialised bubble-breathing technique enables them to stay submerged for up to 18 minutes

In February 2016, scientists at the Laser Interferometer Gravitational-wave Observatory (LIGO) confirmed they made the first-ever detection of gravitational waves (GWs). These events occur when massive objects like neutron stars and black holes merge, sending ripples through spacetime that can be detected millions (and even billions) of light-years away. Since the first event, more than 100 GW events have been confirmed by LIGO, the Advanced VIRGO collaboration, and the Kamioka Gravitational Wave Detector (KAGRA).

Moreover, scientists have found numerous applications for GW astronomy, from probing the interiors of supernovae and neutron stars to measuring the expansion rate of the Universe and learning what it looked like one minute after the Big Bang. In a recent study, an international team of astronomers proposed another application for binary black hole (BBH) mergers: using the earliest mergers in the Universe to probe the first generation of stars (Population III) in the Universe. By modeling how the events evolved, they determined what kind of GW signals the proposed Einstein Telescope (ET) could observe in the coming years.

The study was led by Boyuan Liu, a postdoctoral researcher at the Center for Astronomy of Heidelberg University (ZAH) and a member of the Excellence Cluster STRUCTURES program. He was joined by colleagues from the ZAH and the Institut für Theoretische Astrophysik at Heidelberg University, the Cambridge Institute of Astronomy, the Institute for Physics of Intelligence, the Institut d’Astrophysique de Paris, the Centre de Recherche Astrophysique de Lyon, the Gran Sasso Science Institute (GSSI), the Kavli Institute for Cosmology, the Weinberg Institute for Theoretical Physics, and multiple universities.

From Cosmic Dark to Dawn

Population III stars are the first to have formed in the Universe, roughly 100 to 500 million years after the Big Bang. At the time, hydrogen and helium were the most plentiful forms of matter in the Universe, leading to stars that were very massive and had virtually no metals (low metallicity). These stars were also short-lived, lasting only 2 to 5 million years before they exhausted their hydrogen fuel and went supernova. At this point, the heavier elements created in their cores (lithium, carbon, oxygen, iron, etc.) dispersed throughout the cosmos, leading to Population II and I stars with higher metallicity content.

Astronomers and cosmologists refer to this period as “Cosmic Dawn” since these first stars and galaxies ended the “Cosmic Dark Ages” that preceded it. As Liu explained to Universe Today via email, the properties of Pop III stars were sensitive to the peculiar conditions of the Universe during Cosmic Dawn, which were very different from the present-day conditions. This includes the presence of Dark Matter Haloes, which scientists believe were vital to the formation of the first galaxies:

“The timing of Pop III star formation reflects the pace of early structure formation, which can teach us about the nature of dark matter and gravity. In the standard cosmology model, cosmic structure formation is bottom-up, starting from small halos, which then grow by accretion and mergers to become larger halos. Pop III stars are expected to be massive (> 10 solar masses, reaching up to 1 million solar masses, while present-day stars have an average mass of ~ 0.5 solar masses). So, many of them will explode as supernovae or become massive black holes (BHs) when they run out of fuel for nuclear fusion.”

These Pop III black holes are further believed to be where the first supermassive black holes (SMBHs) in the Universe came from. As astronomers have demonstrated, SMBHs play an important role in the evolution of galaxies. In addition to assisting in the formation of new stars and encouraging galaxy formation in the early Universe, they are also responsible for shutting down star formation in galaxies ca. 2 to 4 billion years after the Big Bang, during the epoch known as “Cosmic Noon.” The growth of these black holes and the UV radiation emitted by Pop III stars reionized the neutral hydrogen and helium that permeated the early Universe.

This led to the major phase transition that ended the Cosmic Dark Ages (ca. 1 billion years after the Big Bang), allowing the Universe to become “transparent” as it is today. However, as Liu stated, how this process started remains unclear:

“Generally speaking, Pop III stars mark the onset of cosmic evolution from a starless (boring) state to the current state with rich phenomena (reionization, diverse populations of galaxies with different masses, morphologies, and compositions, andquasars powered by accreting supermassive BHs). To understand this complex evolution, it isessential to characterize its initial phase dominated by Pop III stars.”

Probing the Early Universe

The confirmation of gravitational waves (GW) was revolutionary for astronomers, and many applications have since been proposed. In particular, scientists are eager to study the primordial GWs created by the Big Bang, which will be possible with next-generation GW detectors like the Laser Interferometer Space Antenna (LISA). As Liu explained, existing GW detectors are mostly dedicated to studying binary black hole (BBH) mergers. The same is true of detectors expected to be built in the near future. Said Liu:

“The GW emission from a BH binary is stronger when they are closer. The GW emission carries away energy and angular momentum from the system such that the two BHs will get closer over time and eventually merge. We can only detect the GW signal at the final stage when they are about to merge. The time taken to reach the final stage is highly sensitive to the initial separation of the BHs. Basically, they have to start close (e.g., less than ~ 10% of the earth-sun distance for BHs below 10 solar masses) to merge within the current age of the Universe to be seen by us.”

The question is, how do two black holes get so close to each other that they will eventually merge? Astronomers currently rely on two evolutionary “channels” (sets of physical processes working together) to model this process: isolated binary stellar evolution (IBSE) and nuclear star cluster-dynamical hardening (NSC-DH). As Liu indicated, the resulting BBH mergers have distinct features in their merger rate and properties, depending on the channel they follow. They contain valuable information about the underlying physical processes.

“Knowledge of evolution channels is necessary to extract such information to fully utilize GWs as a probe for astrophysics and cosmology,” he added.

Modeling BBH Evolution

To determine how black holes come to form binaries that will eventually merge, the team combined both channels into a single theoretical framework based on the semianalytical model Ancient Stars and Local Observables by Tracing Halos (A-SLOTH). This model is the first publicly available code that connects the formation of the first stars and galaxies to observations. “In general, A-SLOTH follows the thermal and chemical evolution of gas along the formation, growth, and mergers of dark matter halos, including star formation and the impact of stars on gas (stellar feedback) at the intermediate scale of individual galaxies/halos,” said Liu.

Current operating facilities in the global network and their planned expansion. Credit: Caltech/MIT/LIGO Lab

They also used the Stellar EVolution for N-body (SEVN) code to predict how stellar binaries evolve into BBHs. They then modeled the orbit of each BBH in their respective dark matter halos and during halo mergers, which allowed them to predict when some BBHs will merge. In other cases, BBHs travel to the center of their galaxies and become part of a nuclear star cluster (NSC), where they are subject to disruptions, ejections, and hardening by gravitational scattering. From this, they followed the evolution of internal binary orbits to the moment of merger or disruption.

Next-Generation Observatories

As Lui explained, their results had significant theoretical and observational implications:

“On the theory side, my work showed that the isolated binary evolution channel dominates at high redshifts (less than 600 million years after the Big Bang) and the merger rate is sensitive to the formation rate and initial statistics of Pop III binary stars. In fact, the majority (> 84%) of BH binaries, especially the most massive ones, are initially too wide to merge within the age of the Universe if they evolve in isolation. But a significant fraction (~ 45 – 64%) of them can merge by dynamical hardening if they fall into NSCs. These predictions are useful for the identification and interpretation of merger origins in observations.”

In terms of observational results, they found that the predicted detection of Pop III BBH mergers is not likely to be discernible by current instruments like LIGO, Advance Virgo, and KAGRA, which generally observe BBH mergers closer to Earth. “[A]ltough Pop III mergers can potentially account for a significant fraction of the most massive BH mergers detected so far (with BHs above 50 solar masses),” said Liu. “It is difficult to learn much about Pop III stars and galaxies in the early Universe from the existing data because the sample size of detected massive mergers is too small.”

However, next-generation detectors like the Einstein Telescope will be more efficient in detecting these distant sources of GWs. Once completed, the ET will allow astronomers to explore the Universe through GWs back to the Cosmic Dark Ages, providing information on the earliest BBH mergers, Pop III stars, and the first SMBHs. “My model predicts that the Einstein Telescope can detect up to 1400 Pop III mergers per year, offering us much better statistics to constrain the relevant physics.”

The paper that describes their findings recently appeared online and is being reviewed for publication in the Monthly Notices of the Royal Astronomical Society.

Further Reading: arXiv

The post Future Gravitational Wave Observatories Could See the Earliest Black Hole Mergers in the Universe appeared first on Universe Today.

In a survey of thousands of people, respondents underestimated the massive difference between the carbon footprints of the wealthiest and poorest individuals – and that’s bad for climate policy

A quantum computing protocol makes it possible to extract energy from seemingly empty space, teleport it to a new location, then store it for later use

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.

Rising demand for electronic devices and electric vehicles has increased the dependence on secondary ion batteries. While lithium-ion batteries are already popular, a promising alternative sodium-ion batteries (SIB) are struggling to get wider acceptance due to slow ion kinetics affecting their performance. A new polymer-based binder called PMAI addresses this issue by forming a functionalized solid electrolyte interphase. The study demonstrated that SIB with PMAI as an anode binder can have exceptional performance and cyclic stability.