Zooming in on dark matter

Cosmologists have zoomed in on the smallest clumps of dark matter in a virtual universe — which could help us to find the real thing in space.

An international team of researchers, including Durham University, UK, used supercomputers in Europe and China to focus on a typical region of a computer-generated universe.

The zoom they were able to achieve is the equivalent of being able to see a flea on the surface of the Moon.

This allowed them to make detailed pictures and analyses of hundreds of virtual dark matter clumps (or haloes) from the very largest to the tiniest.

Dark matter particles can collide with dark matter anti-particles near the centre of haloes where, according to some theories, they are converted into a burst of energetic gamma-ray radiation.

Their findings, published in the journal Nature, could mean that these very small haloes could be identified in future observations by the radiation they are thought to give out.

Co-author Professor Carlos Frenk, Ogden Professor of Fundamental Physics at the Institute for Computational Cosmology, at Durham University, UK, said: “By zooming in on these relatively tiny dark matter haloes we can calculate the amount of radiation expected to come from different sized haloes.

“Most of this radiation would be emitted by dark matter haloes too small to contain stars and future gamma-ray observatories might be able to detect these emissions, making these small objects individually or collectively ‘visible’.

“This would confirm the hypothesised nature of the dark matter, which may not be entirely dark after all.”

Most of the matter in the universe is dark (apart from the gamma radiation they emit in exceptional circumstances) and completely different in nature from the matter that makes up stars, planets and people.

The universe is made of approximately 27 per cent dark matter with the rest largely consisting of the equally mysterious dark energy. Normal matter, such as planets and stars, makes up a relatively small five per cent of the universe.

Galaxies formed and grew when gas cooled and condensed at the centre of enormous clumps of this dark matter — so-called dark matter haloes.

Astronomers can infer the structure of large dark matter haloes from the properties of the galaxies and gas within them.

The biggest haloes contain huge collections of hundreds of bright galaxies, called galaxy clusters, weighing a 1,000 trillion times more than our Sun.

However, scientists have no direct information about smaller dark matter haloes that are too tiny to contain a galaxy. These can only be studied by simulating the evolution of the Universe in a large supercomputer.

The smallest are thought to have the same mass as the Earth according to current popular scientific theories about dark matter that underlie the new research.

The simulations were carried out using the Cosmology Machine supercomputer, part of the DiRAC High-Performance Computing facility in Durham, funded by the Science and Technology Facilities Council (STFC), and computers at the Chinese Academy of Sciences.

By zooming-in on the virtual universe in such microscopic detail, the researchers were able to study the structure of dark matter haloes ranging in mass from that of the Earth to a big galaxy cluster.

Surprisingly, they found that haloes of all sizes have a very similar internal structure and are extremely dense at the centre, becoming increasingly spread out, with smaller clumps orbiting in their outer regions.

The researchers said that without a measure scale it was almost impossible to tell an image of a dark matter halo of a massive galaxy from one of a halo with a mass a fraction of the Sun’s.

Co-author Professor Simon White, of the Max Planck Institute of Astrophysics, Germany, said: “We expect that small dark matter haloes would be extremely numerous, containing a substantial fraction of all the dark matter in the universe, but they would remain mostly dark throughout cosmic history because stars and galaxies grow only in haloes more than a million times as massive as the Sun.

“Our research sheds light on these small haloes as we seek to learn more about what dark matter is and the role it plays in the evolution of the universe.”

The research team, led by the National Astronomical Observatories of the Chinese Academy of Sciences, and including Durham University, UK, the Max Planck Institute for Astrophysics, Germany, and the Center for Astrophysics in Harvard, USA, took five years to develop, test and carry out their cosmic zoom.

The research was funded by the STFC, the European Research Council, the Chinese Academy of Sciences, the Max Planck Society and Harvard University.

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The collective power of the solar system’s dark, icy bodies

The outermost reaches of our solar system are a strange place — filled with dark and icy bodies with nicknames like Sedna, Biden and The Goblin, each of which span several hundred miles across.

Two new studies by researchers at the University of Colorado Boulder may help to solve one of the biggest mysteries about these far away worlds: why so many of them don’t circle the sun the way they should.

The orbits of these planetary oddities, which scientists call “detached objects,” tilt and buckle out of the plane of the solar system, among other unusual behaviors.

“This region of space, which is so much closer to us than stars in our galaxy and other things that we can observe just fine, is just so unknown to us,” said Ann-Marie Madigan, an assistant professor in the Department of Astrophysical and Planetary Sciences (APS) at CU Boulder.

Some researchers have suggested that something big could be to blame — like an undiscovered planet, dubbed “Planet 9,” that scatters objects in its wake.

But Madigan and graduate student Alexander Zderic prefer to think smaller. Drawing on exhaustive computer simulations, the duo makes the case that these detached objects may have disrupted their own orbits — through tiny gravitational nudges that added up over millions of years.

The findings, Madigan said, provide a tantalizing hint to what may be going on in this mysterious region of space.

“We’re the first team to be able to reproduce everything, all the weird orbital anomalies that scientists have seen over the years,” said Madigan, also a fellow at JILA. “It’s crazy to think that there’s still so much we need to do.”

The team published its results July 2 in the Astronomical Journal and last month in the Astronomical Journal Letters.

Power to the asteroids

The problem with studying the outer solar system, Madigan added, is that it’s just so dark.

“Ordinarily, the only way to observe these objects is to have the sun’s rays smack off their surface and come back to our telescopes on Earth,” she said. “Because it’s so difficult to learn anything about it, there was this assumption that it was empty.”

She’s one of a growing number of scientists who argue that this region of space is far from empty — but that doesn’t make it any easier to understand.

Just look at the detached objects. While most bodies in the solar system tend to circle the sun in a flat disk, the orbits of these icy worlds can tilt like a seesaw. Many also tend to cluster in just one slice of the night sky, a bit similar to a compass that only points north.

Madigan and Zderic wanted to find out why. To do that, they turned to supercomputers to recreate, or model, the dynamics of the outer solar system in greater detail than ever before.

“We modeled something that may have once existed in the outer solar system and also added in the gravitational influence of the giant planets like Jupiter,” said Zderic, also of APS.

In the process, they discovered something unusual: the icy objects in their simulations started off orbiting the sun like normal. But then, over time, they began to pull and push on each other. As a result, their orbits grew wonkier until they eventually resembled the real thing. What was most remarkable was that they did it all on their own — the asteroids and minor planets didn’t need a big planet to throw them for a loop.

“Individually, all of the gravitational interactions between these small bodies are weak,” Madigan said. “But if you have enough of them, that becomes important.”

Earth times 20

Madigan and Zderic had seen hints of similar patterns in earlier research, but their latest results provide the most exhaustive evidence yet.

The findings also come with a big caveat. In order to make Madigan and Zderic’s theory of “collective gravity” work, the outer solar system once needed to contain a huge amount of stuff.

“You needed objects that added up to something on the order of 20 Earth masses,” Madigan said. “That’s theoretically possible, but it’s definitely going to be bumping up against people’s beliefs.”

One way or another, scientists should find out soon. A new telescope called the Vera C. Rubin Observatory is scheduled to come online in Chile in 2022 and will begin to shine a new light on this unknown stretch of space.

“A lot of the recent fascination with the outer solar system is related to technological advances,” Zderic said. “You really need the newest generation of telescopes to observe these bodies.”

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New sunspots potentially herald increased solar activity

On May 29, 2020, a family of sunspots — dark spots that freckle the face of the Sun, representing areas of complex magnetic fields — sported the biggest solar flare since October 2017. Although the sunspots are not yet visible (they will soon rotate into view over the left limb of the Sun), NASA spacecraft spotted the flares high above them.

The flares were too weak to pass the threshold at which NOAA’s Space Weather Prediction Center (which is the U.S. government’s official source for space weather forecasts, watches, warnings and alerts) provides alerts. But after several months of very few sunspots and little solar activity, scientists and space weather forecasters are keeping their eye on this new cluster to see whether they grow or quickly disappear. The sunspots may well be harbingers of the Sun’s solar cycle ramping up and becoming more active.

Or, they may not. It will be a few more months before we know for sure.

As the Sun moves through its natural 11-year cycle, in which its activity rises and falls, sunspots rise and fall in number, too. NASA and NOAA track sunspots in order to determine, and predict, the progress of the solar cycle — and ultimately, solar activity. Currently, scientists are paying close attention to the sunspot number as it’s key to determining the dates of solar minimum, which is the official start of Solar Cycle 25. This new sunspot activity could be a sign that the Sun is possibly revving up to the new cycle and has passed through minimum.

However, it takes at least six months of solar observations and sunspot-counting after a minimum to know when it’s occurred. Because that minimum is defined by the lowest number of sunspots in a cycle, scientists need to see the numbers consistently rising before they can determine when exactly they were at the bottom. That means solar minimum is an instance only recognizable in hindsight: It could take six to 12 months after the fact to confirm when minimum has actually passed.

This is partly because our star is extremely variable. Just because the sunspot numbers go up or down in a given month doesn’t mean it won’t reverse course the next month, only to go back again the month after that. So, scientists need long-term data to build a picture of the Sun’s overall trends through the solar cycle. Commonly, that means the number we use to compare any given month is the average sunspot number from six months both backward and forward in time — meaning that right now, we can confidently characterize what October 2019 looks like compared to the months before it (there were definitely fewer sunspots!), but not yet what November looks like compared to that.

On May 29, at 3:24 a.m. EST, a relatively small M-class solar flare blazed from these sunspots. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer where GPS and communications signals travel. The intensity of this flare was below the threshold that could affect geomagnetic space and below the threshold for NOAA to create an alert.

Nonetheless, it was the first M-class flare since October 2017 — and scientists will be watching to see if the Sun is indeed beginning to wake up.

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Could dark matter be hiding in existing data?

Dark matter has so far defied every type of detector designed to find it. Because of its huge gravitational footprint in space, we know dark matter must make up about 85 percent of the total mass of the universe, but we don’t yet know what it’s made of.

Several large experiments that hunt for dark matter have searched for signs of dark matter particles knocking into atomic nuclei via a process known as scattering, which can produce tiny flashes of light and other signals in these interactions.

Now a new study, led by researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley, suggests new paths for catching the signals of dark matter particles that have their energy absorbed by these nuclei.

The absorption process could give an affected atom a kick that causes it to eject a lighter, energized particle such as an electron, and it might produce other types of signals, too, depending on the nature of the dark matter particle.

The study focuses mostly on those cases where an electron or neutrino is ejected as the dark matter particle strikes an atom’s nucleus.

Published May 4 in Physical Review Letters, the study proposes that some existing experiments, including ones that search for dark matter particles and processes related to neutrinos — ghostly, detectable particles that can pass through most matter and have the ability to change into different forms — can easily be broadened to also look for these absorption-related types of telltale dark matter signals.

Also, the researchers propose that new searches in previously collected particle detector data could possibly turn up these overlooked dark matter signals.

“In this field, we’ve had a certain idea in mind about well-motivated candidates for dark matter, such as the WIMP,” or weakly interacting massive particle, said Jeff Dror, the lead author of the study who is a postdoctoral researcher in Berkeley Lab’s Theory Group and UC Berkeley’s Berkeley Center for Theoretical Physics.

Dark matter pushes at the boundaries of the known fundamental laws of physics, encapsulated in the Standard Model of particle physics, and “The WIMP paradigm is very easy to build into the Standard Model, but we haven’t found it for a long time,” Dror noted.

So, physicists are now considering other places that dark matter particles may be hiding, and other particle possibilities such as theorized “sterile neutrinos” that could also be brought into the family of particles known as fermions — which includes electrons, protons, and neutrinos.

“It’s easy, with small modifications to the WIMP paradigm, to accommodate a whole different type of signal,” Dror said. “You can make a huge amount of progress with very little cost if you step back a little bit in the way we’ve been thinking about dark matter.”

Robert McGehee, a UC Berkeley graduate student, and Gilly Elor of the University of Washington were study co-authors.

The researchers note that the range of new signals they are focusing on opens up an “ocean” of dark matter particle possibilities: namely as-yet-undiscovered fermions with masses lighter than the typical range considered for WIMPs. They could be close cousins of sterile neutrinos, for example.

The study team considered absorption processes known as “neutral current,” in which nuclei in the detector material recoil, or get jolted by their collision with dark matter particles, producing distinct energy signatures that can be picked up by the detector; and also those known as “charged current,” which can produce multiple signals as a dark matter particle strikes a nucleus, causing a recoil and the ejection of an electron.

The charge current process can also involve nuclear decay, in which other particles are ejected from a nucleus as a sort of domino effect triggered by the dark matter absorption.

Looking for the study’s suggested signatures of both the neutral current and charge current processes could open up “orders of magnitude of unexplored parameter space,” the researchers note. They focus on energy signals in the MeV, which means millions of electron volts. An electron volt is a measure of energy that physicists use to describe the masses of particles. Meanwhile, typical WIMP searches are now sensitive to particle interactions with energies in the keV range, or thousands of electron volts.

For the various particle interactions the researchers explored in the study, “You can predict what is the energy spectrum of the particle coming out or the nucleon that’s getting the ‘kick,'” Dror said. Nucleon refers to the positively charged proton or uncharged neutron that resides in an atom’s nucleus and that could absorb energy when struck by a dark matter particle. These absorption signals could possibly be more common than the other types of signals that dark matter detectors are typically designed to find, he added — we just don’t know yet.

Experiments that have large volumes of detector material, with high sensitivity and very low background “noise,” or unwanted interference from other types of particle signals, are particularly suited for this expanded search for different types of dark matter signals, Dror said.

LUX-ZEPLIN (LZ), for example, an ultrasensitive Berkeley Lab-led dark matter search project under construction in a former South Dakota mine, is a possible candidate as it will use about 10 metric tons of liquid xenon as its detector medium and is designed to be heavily shielded from other types of particle noise.

Already, the team of researches participating in the study has worked with the team operating the Enriched Xenon Observatory (EXO), an underground experiment searching for a theorized process known as neutrino-less double beta decay using liquid xenon, to open up its search to these other types of dark matter signals.

And for similar types of experiments that are up and running, “The data is already basically sitting there. It’s just a matter of looking at it,” Dror said.

The researchers name a laundry list of candidate experiments around the world that could have relevant data and search capabilities that could be used to find their target signals, including: CUORE, LZ predecessor LUX, PandaX-II, XENON1T, KamLAND-Zen, SuperKamiokande, CDMS-II, DarkSide-50, and Borexino among them.

As a next step, the research team is hoping to work with experiment collaborations to analyze existing data, and to find out whether search parameters of active experiments can be adjusted to search for other signals.

“I think the community is starting to become fairly aware of this,” Dror said, adding, “One of the biggest questions in the field is the nature of dark matter. We don’t know what it is made out of, but answering these questions could be within our reach in the near future. For me, that’s a huge motivation to keep pushing — there is new physics out there.”

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First-ever comprehensive geologic map of the moon

Have you ever wondered what kind of rocks make up those bright and dark splotches on the moon? Well, the USGS has just released a new authoritative map to help explain the 4.5-billion-year-old history of our nearest neighbor in space.

For the first time, the entire lunar surface has been completely mapped and uniformly classified by scientists from the USGS, in collaboration with NASA and the Lunar Planetary Institute.

The lunar map, called the “Unified Geologic Map of the Moon,” will serve as the definitive blueprint of the moon’s surface geology for future human missions and will be invaluable for the international scientific community, educators and the public-at-large. The digital map is available online now and shows the moon’s geology in incredible detail (1:5,000,000 scale).

“People have always been fascinated by the moon and when we might return,” said current USGS Director and former NASA astronaut Jim Reilly. “So, it’s wonderful to see USGS create a resource that can help NASA with their planning for future missions.”

To create the new digital map, scientists used information from six Apollo-era regional maps along with updated information from recent satellite missions to the moon. The existing historical maps were redrawn to align them with the modern data sets, thus preserving previous observations and interpretations. Along with merging new and old data, USGS researchers also developed a unified description of the stratigraphy, or rock layers, of the moon. This resolved issues from previous maps where rock names, descriptions and ages were sometimes inconsistent.

“This map is a culmination of a decades-long project,” said Corey Fortezzo, USGS geologist and lead author. “It provides vital information for new scientific studies by connecting the exploration of specific sites on the moon with the rest of the lunar surface.”

Elevation data for the moon’s equatorial region came from stereo observations collected by the Terrain Camera on the recent SELENE (Selenological and Engineering Explorer) mission led by JAXA, the Japan Aerospace Exploration Agency. Topography for the north and south poles was supplemented with NASA’s Lunar Orbiter Laser Altimeter data.

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ClimaCell Announces Weather API Improvements Following Dark Sky API’s Demise

Last month’s announcement that Apple had purchased the popular Dark Sky weather app, and would be killing the API, left a significant void in the weather API landscape. It appears that ClimaCell is hoping to fill this void with well-timed advancements to its ClimaCell Weather API.

Andrew Orr, a writer for, made the observation earlier today that ClimaCell’s announcement of UI improvements and API enhancements is likely more than a coincidence. The company’s newly designed user interface is aimed at highlighting the way that weather data affects life more broadly. Specifically, the UI highlights Road Risk, Wildfires, and Air Quality. ClimaCell also notes improved customizability in an effort to ensure the best user experience possible in all applications. The API also sees the addition of a new data layer that will provide access to a proprietary index analyzing pollen seasonality. 

The API has a free tier for developers that are looking to test out the platform. Anyone requiring over 30,000 calls/month will need to above to paid tiers. Make sure to check out the API documentation for more detail. 

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Author: <a href="">KevinSundstrom</a>


Looking for dark matter

Dark matter, which cannot be physically observed with ordinary instruments, is thought to account for well over half the matter in the Universe, but its properties are still mysterious. One commonly held theory states that it exists as ‘clumps’ of extremely light particles. When the earth passes through such a clump, the fundamental properties of matter are altered in ways that can be detected if instruments are sensitive enough. Physicists Rees McNally and Tanya Zelevinsky from Columbia University, New York, USA, have now published a paper in EPJ D proposing two new methods of looking for such perturbations and, thus, dark matter. This paper is part of a special issue of the journal on quantum technologies for gravitational physics.

Until now, searches for dark matter clumps have relied on the fact that tiny changes in the values of fundamental constants will alter the ‘tick rate’ of atomic clocks, some of which may be precise enough to pick up this difference. McNally and Zelevinsky’s work adds methods that involve measuring a small extra ‘push’ or acceleration on normal matter caused by the clump, using, firstly, gravity sensors and, secondly, gravitational wave detectors. Gravity sensors are already spread around the world in the IGETS network, which is used for geological research; and scientists at the LIGO observatories in the United States are already looking for gravitational waves. Thus, McNally and Zelevinsky can mine the data from these ongoing experiments for evidence of dark matter.

McNally explains that this work was inspired by two things: the benefits of re-purposing existing experiments, and science fiction. “I enjoy novels like A Fire Upon the Deep [by Vernor Vinge] and The Three-Body Problem [by Liu Cixin] that explore what might happen if fundamental constants change, and it’s fun to explore such things in the real world.” As for practical applications of this work, however, he advised taking things one step at a time. “First we need to find out what Dark Matter is, then maybe we can find out how to use it.”

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Journal Reference:

  1. Rees L. McNally, Tanya Zelevinsky. Constraining domain wall dark matter with a network of superconducting gravimeters and LIGO. The European Physical Journal D, 2020; 74 (4) DOI: 10.1140/epjd/e2020-100632-0

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New minor planets found beyond Neptune

Using data from the Dark Energy Survey (DES), researchers have found more than 300 trans-Neptunian objects (TNOs), minor planets located in the far reaches of the solar system, including more than 100 new discoveries. Published in The Astrophysical Journal Supplement Series, the study also describes a new approach for finding similar types of objects and could aid future searches for the hypothetical Planet Nine and other undiscovered planets. The work was led by graduate student Pedro Bernardinelli and professors Gary Bernstein and Masao Sako.

The goal of DES, which completed six years of data collection in January, is to understand the nature of dark energy by collecting high-precision images of the southern sky. While DES wasn’t specifically designed with TNOs in mind, its breadth and depth of coverage made it particularly adept at finding new objects beyond Neptune. “The number of TNOs you can find depends on how much of the sky you look at and what’s the faintest thing you can find,” says Bernstein.

Because DES was designed to study galaxies and supernovas, the researchers had to develop a new way to track movement. Dedicated TNO surveys take measurements as frequently as every hour or two, which allows researchers to more easily track their movements. “Dedicated TNO surveys have a way of seeing the object move, and it’s easy to track them down,” says Bernardinelli. “One of the key things we did in this paper was figure out a way to recover those movements.”

Using the first four years of DES data, Bernardinelli started with a dataset of 7 billion “dots,” all of the possible objects detected by the software that were above the image’s background levels. He then removed any objects that were present on multiple nights — things like stars, galaxies, and supernova — to build a “transient” list of 22 million objects before commencing a massive game of “connect the dots,” looking for nearby pairs or triplets of detected objects to help determine where the object would appear on subsequent nights.

With the 7 billion dots whittled down to a list of around 400 candidates that were seen over at least six nights of observation, the researchers then had to verify their results. “We have this list of candidates, and then we have to make sure that our candidates are actually real things,” Bernardinelli says.

To filter their list of candidates down to actual TNOs, the researchers went back to the original dataset to see if they could find more images of the object in question. “Say we found something on six different nights,” Bernstein says. “For TNOs that are there, we actually pointed at them for 25 different nights. That means there’s images where that object should be, but it didn’t make it through the first step of being called a dot.”

Bernardinelli developed a way to stack multiple images to create a sharper view, which helped confirm whether a detected object was a real TNO. They also verified that their method was able to spot known TNOs in the areas of the sky being studied and that they were able to spot fake objects that were injected into the analysis. “The most difficult part was trying to make sure that we were finding what we were supposed to find,” says Bernardinelli.

After many months of method-development and analysis, the researchers found 316 TNOs, including 245 discoveries made by DES and 139 new objects that were not previously published. With only 3,000 objects currently known, this DES catalog represents 10% of all known TNOs. Pluto, the best-known TNO, is 40 times farther away from the sun than Earth is, and the TNOs found using the DES data range from 30 to 90 times Earth’s distance from the sun. Some of these objects are on extremely long-distance orbits that will carry them far beyond Pluto.

Now that DES is complete, the researchers are rerunning their analysis on the entire DES dataset, this time with a lower threshold for object detection at the first filtering stage. This means that there’s an even greater potential for finding new TNOs, possibly as many as 500, based on the researchers’ estimates, in the near future.

The method developed by Bernardinelli can also be used to search for TNOs in upcoming astronomy surveys, including the new Vera C. Rubin Observatory. This observatory will survey the entire southern sky and will be able to detect even fainter and more distant objects than DES. “Many of the programs we’ve developed can be easily applied to any other large datasets, such as what the Rubin Observatory will produce,” says Bernardinelli.

This catalog of TNOs will also be a useful scientific tool for research about the solar system. Because DES collects a wide spectrum of data on each detected object, researchers can attempt to figure out where the TNO originated from, since objects that form more closely to the Sun have are expected to have different colors than those that originated in more distant and colder locations. And, by studying the orbits of these objects, researchers might be one step closer to finding Planet Nine, a hypothesized Neptune-sized planet that’s thought to exist beyond Pluto.

“There are lots of ideas about giant planets that used to be in the solar system and aren’t there anymore, or planets that are far away and massive but too faint for us to have noticed yet,” says Bernstein. “Making the catalog is the fun discovery part. Then when you create this resource; you can compare what you did find to what somebody’s theory said you should find.”

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Scientists shed light on mystery of dark matter

Scientists have identified a sub-atomic particle that could have formed the “dark matter” in the Universe during the Big Bang.

Up to 80% of the Universe could be dark matter, but despite many decades of study, its physical origin has remained an enigma. While it cannot be seen directly, scientists know it exists because of its interaction via gravity with visible matter like stars and planets. Dark matter is composed of particles that do not absorb, reflect or emit light.

Now, nuclear physicists at the University of York are putting forward a new candidate for the mysterious matter — a particle they recently discovered called the d-star hexaquark.

The particle is composed of six quarks — the fundamental particles that usually combine in trios to make up protons and neutrons. Importantly, the six quarks in a d-star result in a boson particle, which means that when many d-stars are present they can combine together in very different ways to the protons and neutrons.

The research group at York suggest that in the conditions shortly after the Big Bang, many d-star hexaquarks could have grouped together as the universe cooled and expanded to form the fifth state of matter — Bose-Einstein condensate.

Dr MIkhail Bashkanov and Professor Daniel Watts from the the department of physics at the University of York recently published the first assessment of the viability of this new dark matter candididate.

Professor Daniel Watts from the department of physics at the University of York said: “The origin of dark matter in the universe is one of the biggest questions in science and one that, until now, has drawn a blank. Our first calculations indicate that condensates of d-stars are a feasible new candidate for dark matter. This new result is particularly exciting since it doesn’t require any concepts that are new to physics.”

Co-author of the paper, Dr Mikhail Bashkanov from the Department of Physics at the University of York said: “The next step to establish this new dark matter candidate will be to obtain a better understanding of how the d-stars interact — when do they attract and when do they repel each other.

“We are leading new measurements to create d-stars inside an atomic nucleus and see if their properties are different to when they are in free space. “

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Puerto Rico Goes Dark (Again) as Earthquakes Rattle Island

A series of earthquakes left Puerto Rico in the dark this week as power outages swept nearly the entire island. About 80 percent of utility customers had power restored by Friday afternoon, yet authorities warned it could take weeks to stabilize the overall system. 

A 6.4-magnitude earthquake rocked the U.S. territory on 7 January following days of seismic activity. Temblors and aftershocks leveled buildings, split streets, and severely damaged the island’s largest power plant, Costa Sur. The blackouts hit a system still reeling from 2017’s Hurricane Maria—which knocked out the entire grid and required $3.2 billion in repairs.