Testing a theory of supermassive black holes with 100 newly described 'blazars'

For some supermassive black holes, matter outside the event horizon is propelled at high speed in a jet that can be detected across the universe. When the jet is pointed in the direction of the Earth, it is typically called a blazar. Penn State researchers have characterized more than a hundred relatively dim blazars and used them to test a contentious theory of blazar emissions.
Illustration Credit: NASA/JPL-Caltech/GSFC

More than a hundred blazars — distant and active galaxies with a central supermassive black hole that drives powerful jets — have been newly characterized by Penn State researchers from a catalog of previously unclassified high-energy cosmic emissions. The new blazars, which are dim relative to more typical blazars, have allowed the researchers to test a controversial theory of blazar emissions, informing our understanding of black hole growth and even theories of general relativity and high-energy particle physics.

A paper describing the blazars and the theory has been accepted for publication in the Astrophysical Journal, and the peer-reviewed accepted version appears online on the preprint server arXiv.

Supermassive black holes can be millions or billions of times the mass of our sun. In some cases, matter outside of the black hole’s event horizon is propelled in a jet, accelerating to nearly the speed of light and sending emissions across the universe. When the jet happens to be pointed directly at the Earth, the system is typically called a blazar.

NUS scientists develop a novel light-field sensor for 3D scene construction with unprecedented angular resolution

Prof Liu Xiaogang (right) and Dr Yi Luying from the NUS Department of Chemistry capturing a 3D image of a model using the light-field sensor.
Photo Credit: Courtesy of National University of Singapore

Color-encoding technique for light-field imaging has potential applications in fields such as autonomous driving, virtual reality and biological imaging

A research team from the National University of Singapore (NUS) Faculty of Science, led by Professor Liu Xiaogang from the Department of Chemistry, has developed a 3D imaging sensor that has an extremely high angular resolution, which is the capacity of an optical instrument to distinguish points of an object separated by a small angular distance, of 0.0018o. This innovative sensor operates on a unique angle-to-color conversion principle, allowing it to detect 3D light fields across the X-ray to visible light spectrum.  

A light field encompasses the combined intensity and direction of light rays, which the human eyes can process to precisely detect the spatial relationship between objects. Traditional light sensing technologies, however, are less effective. Most cameras, for instance, can only produce two-dimensional images, which is adequate for regular photography but insufficient for more advanced applications, including virtual reality, self-driving cars, and biological imaging. These applications require precise 3D scene construction of a particular space.

Ancestral mitoviruses discovered in mycorrhizal fungi

Arbuscular mycorrhizal (AM) fungi in the Glomeromycotina colonize plant roots (left, micrograph) and deliver water and nutrients from soil (right).
Image Credit: Tatsuhiro Ezawa

A new group of mitochondrial viruses confined to the arbuscular mycorrhizal fungi Glomeromycotina may represent an ancestral lineage of mitoviruses.

Mitochondria are organelles in the cells of almost all eukaryotes — organisms with cells that have a nucleus. They were originally free-living bacteria capable of generating energy in the presence of oxygen; then engulfed by an ancestral eukaryotic cell where they became mitochondria, the site of cellular respiration and many important metabolic processes. In humans, dysfunctions of mitochondria are associated with aging and many diseases.

Bacteriophages are viruses that infect bacteria. As former bacteria, there are also viruses that infect mitochondria, known as mitoviruses, which evolved from bacteriophages. While mitoviruses have been found in fungi, plants, and invertebrates, they are not well studied.

Associate Professor Tatsuhiro Ezawa at Hokkaido University, Professor Luisa Lanfranco at University of Torino, and Dr. Massimo Turina at National Research Council of Italy (CNR) Torino led an international team to discover a new group of mitoviruses, called large duamitoviruses. Their findings were published in the journal mBio.

Celestial monsters at the origin of globular clusters

Scientists have found strong evidence that supermassive stars existed within globular clusters when they formed 13 billion years ago. Here, an image of the globular cluster M13, 22 000 light years from Earth, consisting of a million stars squeezed into a space 150 light years across.
Image Credits: HST STScI NASA ESA

A team from the universities of Geneva, Paris and Barcelona has found strong evidence that supermassive stars can explain the anomalies observed in large clusters of stars.

Globular clusters are the most massive and oldest star clusters in the Universe. They can contain up to 1 million of them. The chemical composition of these stars, born at the same time, shows anomalies that are not found in any other population of stars. Explaining this specificity is one of the great challenges of astronomy. After having imagined that supermassive stars could be at the origin, a team from the Universities of Geneva and Barcelona, and the Institut d’Astrophysique de Paris (CNRS and Sorbonne University) believes it has discovered the first chemical trace attesting to their presence in globular proto-clusters, born about 440 million years after the Big Bang. These results, obtained thanks to observations by the James-Webb space telescope, are to be found in Astronomy and Astrophysics.

Globular clusters are very dense groupings of stars distributed in a sphere, with a radius varying from a dozen to a hundred light years. They can contain up to 1 million stars and are found in all types of galaxies. Ours is home to about 180 of them. One of their great mysteries is the composition of their stars: why is it so varied? For instance, the proportion of oxygen, nitrogen, sodium and aluminum varies from one star to another. However, they were all born at the same time, within the same cloud of gas. Astrophysicists speak of "abundance anomalies".

Cancer may lurk in ‘normal looking’ skin

Researchers say reducing skin mutations in 'normal looking' skin could reduce the risk of skin cancers.
Photo Credit: Anna Nekrashevich

A University of Queensland study has found skin with few visible freckles or blemishes may still carry sun-damaged DNA mutations that can trigger cancer.

Researchers from UQ’s Frazer Institute Dermatology Research Centre investigated the relationship between the number of mutations found in ‘normal looking’ skin and the number of a person’s past skin cancers.

Lead author and PhD candidate Ms. Ho Yi Wong said the findings show Australians can still have a high number of mutations in skin they think looks normal.

“We took skin samples from the forearms of 37 skin cancer patients which were frequently sun exposed,” Ms. Wong said.

“They had an average of 4-5 times more mutations in normal looking skin compared to similar studies overseas.

Jellybeans – a sweet solution for overcrowded circuitry in quantum computer chips

Engineers show that a jellybean-shaped quantum dot creates more breathing space in a microchip packed with qubits.

The silicon microchips of future quantum computers will be packed with millions, if not billions of qubits – the basic units of quantum information – to solve the greatest problems facing humanity. And with millions of qubits needing millions of wires in the microchip circuitry, it was always going to get cramped in there.

But now engineers at UNSW Sydney have made an important step towards solving a long-standing problem about giving their qubits more breathing space -- and it all revolves around jellybeans.

Not the kind we rely on for a sugar hit to get us past the 3pm slump. But jellybean quantum dots –elongated areas between qubit pairs that create more space for wiring without interrupting the way the paired qubits interact with each other.

As lead author Associate Professor Arne Laucht explains, the jellybean quantum dot is not a new concept in quantum computing, and has been discussed as a solution to some of the many pathways towards building the world’s first working quantum computer.

Delivery of antioxidants to liver mitochondria

Damage to the liver induced by acetaminophen (dotted blue outlines) is almost completely mitigated by CoQ10-MITO-Porter (right), compared to the effect of phosphate buffered saline (left) and direct administration of CoQ10(center).
Image Credit: Mitsue Hibino, et al. Scientific Reports. May 10, 2023

A new drug delivery system delivers an antioxidant directly to mitochondria in the liver, mitigating the effects of oxidative stress.

Mitochondria are microscopic organelles found within cells, and are well-known as the “powerhouse of the cell.” They are by far the largest producer of the molecule adenosine triphosphate (ATP), which provides energy to many processes in living cells. The process by which mitochondria synthesize ATP generates a large amount of reactive oxygen species (ROS), chemical groups that are highly reactive. 

In a healthy cell, the ROS is controlled by the mitochondria; however, when this balance is lost, the excess ROS damages the mitochondria and subsequently cells and tissues. This phenomenon, known as oxidative stress, can cause premature aging and disease. The ROS that causes oxidative stress can be controlled by antioxidants.

A research team led by Professor Yuma Yamada, Distinguished Professor Hideyoshi Harashima and Assistant Professor Mitsue Hibino at Hokkaido University have developed a system to deliver antioxidants to mitochondria to mitigate the effects of excess ROS. Their findings were published in Scientific Reports.

Researchers measure the light emitted by a sub-Neptune planet’s atmosphere for the first time

U-M graduate student Isaac Malsky, a co-author of the study, ran three-dimensional models for the planet, testing models with and without clouds and hazes, to see how these aerosols shape the thermal structure of the planet and help interpret the data.
Illustration Credit: NASA/JPL-Caltech/R. Hurt (IPAC)

For more than a decade, astronomers have been trying to get a closer look at GJ 1214b, an exoplanet 40 light-years away from Earth.

Their biggest obstacle is a thick layer of haze that blankets the planet, shielding it from the probing eyes of space telescopes and stymying efforts to study its atmosphere. But now, NASA’s new JWST has solved that issue. The telescope’s infrared technology allows it to see planetary objects and features that were previously obscured by hazes, clouds or space dust, aiding astronomers in their search for habitable planets and early galaxies.

A team of researchers from the University of Michigan and University of Maryland used JWST to observe GJ 1214b’s atmosphere by measuring the heat it emits while orbiting its host star. Their results, published in the journal Nature, represent the first time anyone has directly detected the light emitted by a sub-Neptune exoplanet—a category of planets that are larger than Earth but smaller than Neptune.

Entangled quantum circuits

Par­tial sec­tion of the 30-​meter-long quantum con­nec­tion between two su­per­con­duct­ing cir­cuits. The va­cuum tube (center) con­tains a mi­crowave wave­guide that is cooled to around –273°C and con­nects the two quantum cir­cuits.
Pho­to Credit: ETH Zurich / Daniel Wink­ler

A group of researchers led by Andreas Wallraff, Professor of Solid State Physics at ETH Zurich, has performed a loophole-free Bell test to disprove the concept of “local causality” formulated by Albert Einstein in response to quantum mechanics. By showing that quantum mechanical objects that are far apart can be much more strongly correlated with each other than is possible in conventional systems, the researchers have provided further confirmation for quantum mechanics. What’s special about this experiment is that the researchers were able for the first time to perform it using superconducting circuits, which are considered to be promising candidates for building powerful quantum computers.

Researchers Track Endangered Nassau Grouper Eggs with Underwater Microscope

Nassau grouper spawning aggregation off Little Cayman, Cayman Islands. Credit: Jason Belport
 Photo Credit: Grouper Moon Project

Scripps Oceanography researchers show fertilized eggs stayed local, but in some years drifted to nearby islands.

Each winter off the western tip of the Caribbean island of Little Cayman, thousands of endangered Nassau grouper gather to spawn under the light of the full moon. The fish pack the coral reef and when the ritual begins individual females dash out of the fray straight up towards the surface with multiple males in pursuit. During these vertical bursts, females release their eggs and the males jostle to fertilize them, leaving milky plumes drifting in the moonlit sea.  

These precious fertilized eggs are the engine that powers the still-limited recovery of this critically endangered species that is a key reef predator and was once the target of an important fishery in the Caribbean. But where do these eggs end up after they’re cast adrift? 

Scientists at the University of California San Diego’s Scripps Institution of Oceanography, Oregon State University (OSU), and the conservation organization Reef Environmental Education Foundation (REEF) teamed up with the Cayman Islands Department of the Environment to address this question by physically tracking clouds of tiny, transparent Nassau grouper eggs through the night with an underwater microscope developed by Scripps Oceanography Marine Physical Laboratory scientist Jules Jaffe. 

Physicists discover ‘stacked pancakes of liquid magnetism’

Physicists at Rice University and Ames Laboratory at Iowa State University discovered “stacked pancakes of liquid magnetism” that arise in some helical magnets due to changes in the arrangement of magnetic dipoles when the material warms. At very low temperatures (bottom panel), the orderly arrangement of dipoles leads to magnetism. At high temperature (top panel), dipoles are disordered and the material is nonmagnetic. Pancakes of liquidlike magnetism (middle panel) arise at an intermediate temperature where magnetic interactions within horizontal 2D layers are much stronger than vertical interactions between layers.
Illustration Credit: M. Butcher, courtesy of A. Nevidomskyy/Rice University

Physicists have discovered “stacked pancakes of liquid magnetism” that may account for the strange electronic behavior of some layered helical magnets.

The materials in the study are magnetic at cold temperatures and become nonmagnetic as they thaw. Experimental physicist Makariy Tanatar of Ames National Laboratory at Iowa State University noticed perplexing electronic behavior in layered helimagnetic crystals and brought the mystery to the attention of Rice theoretical physicist Andriy Nevidomskyy, who worked with Tanatar and former Rice graduate student Matthew Butcher to create a computational model that simulated the quantum states of atoms and electrons in the layered materials.

Giants of the Jurassic seas were twice the size of a killer whale

An artist’s impression of the pliosaur
Illustration Credit: Megan Jacobs, University of Portsmouth

Over 20 years ago, the BBC’s "Walking with Dinosaurs" TV documentary series showed a 25-meter long Liopleurodon. This sparked heated debates over the size of this pliosaur as it was thought to have been wildly overestimated and more likely to have only reached an adult size of just over six meters long.

The speculation was set to continue, but now a chance discovery in an Oxfordshire museum has led to University of Portsmouth paleontologists publishing a paper on a similar species potentially reaching a whopping 14.4 meters - twice the size of a killer whale. 

Professor David Martill from the University of Portsmouth’s School of the Environment, Geography and Geosciences, said: “I was a consultant for the BBC’s pilot program ‘Cruel Sea’ and I hold my hands up - I got the size of Liopleurodon horrendously wrong. I based my calculations on some fragmentary material which suggested a Liopleurodon could grow to a length of 25 meters, but the evidence was scant and it caused a lot of controversy at the time.

“The size estimate on the BBC back in 1999 was overdone, but now we have some evidence that is much more reliable after a serendipitous discovery of four enormous vertebrate.”

SwRI selected for phase a study to develop next-generation NOAA coronagraph

SwRI used internal funding to develop SwSCOR three-stage lens system mounted behind a single-pylon external occulter to minimize distortion across the field of view. A polarizer wheel is placed in front of the first lens. The current Phase A study will study options for the external occulter.
Illustration Credit: Courtesy of SwRI

NASA has selected Southwest Research Institute for a Phase A study to develop SwRI’s Space Weather Solar Coronagraph (SwSCOR) on behalf of the National Oceanic and Atmospheric Administration (NOAA). NOAA’s Space Weather Next Program is charged with providing critical data for its space weather prediction center. SwRI is one of five organizations developing a definition-phase study to produce the next-generation NOAA L1 Series COR instrument to detect and characterize Earth-directed coronal mass ejections (CMEs).

CMEs are huge bursts of coronal plasma threaded with intense magnetic fields ejected from the Sun over the course of several hours. CMEs arriving at Earth can generate geomagnetic storms, which can cause anomalies in and disruptions to modern conveniences such as electronic grids and GPS systems. Coronagraphs are instruments that block out light emitted by the Sun’s surface so that its outer atmosphere, or corona, can be observed.

A New Cancer Mechanism: Failed Cell Housekeeping

Illustration of single-stranded RNA
Illustration Credit: National Institute of General Medical Sciences

New research pinpoints a gene that, when mutated, causes cancer through a mechanism scientists haven’t seen before: cells lose the ability to dispose of their trash, namely defective strands of RNA.

This mechanism appears to cut across many different malignancies and could present a whole new set of molecules for cancer drugs to target, as reported in the journal Science by a team from Harvard Medical School, Boston Children’s Hospital, and Dana-Farber Cancer Institute.

While studying zebrafish, Megan Insco, HMS instructor in medicine who was a research fellow in the lab of Leonard Zon at HMS and Boston Children’s at the time, identified a tumor-suppressing gene called CDK13. When mutated, it expedited the development of melanoma. 

The same gene was also mutated in many human melanomas, she found.

But what was really surprising was how the CDK13 mutation causes cancer.

Investigating the RNAs made by melanoma cells, Insco saw multiple short, defective RNAs. She immediately shared this odd finding with Zon.

Researchers map the genome of the world’s grumpiest cat

The mighty roar of a grumpy and angry Pallas' cat (Otocolobus manul)
Photo Credit: Johannes Heel

University of Minnesota researchers recently led successful efforts to build the first genome for Pallas’s cat (Otocolobus manul), a small wild cat native to central Asia known for its grumpy facial expression. The cat, which faces growing challenges from climate change, habitat fragmentation, and poaching, had no available genetic resources to help with conservation prior to this study. 

The study, published in NAR Genomics and Bioinformatics, was led by Nicole Flack, a doctoral candidate in the College of Veterinary Medicine, along with Christopher Faulk, a professor in the College of Food, Agricultural, and Natural Resource Sciences. 

The researchers used blood samples from Tater, a 6-year-old Pallas’s cat who lives at the Utica Zoo in New York, to construct a high-quality diploid nuclear genome assembly, a representative map of genes for the species.

The study results include confirmation that the Pallas’s cat is more closely related to certain wild cat species and less related to house cat species than some previous studies have suggested.