Category: 7. Science

Astronomers studying the night sky from the Southern Hemisphere have uncovered a supernova — the powerful explosion of a star — that appears to detonated twice. The unique discovery of the double-detonation supernova comes as two smaller nova explosions have caused stars to suddenly become visible to the naked eye.

A supernova, according to NASA, is an extremely bright, super-powerful explosion of a star and the biggest explosion that humans have ever seen. Astronomers uncovered the rare double-detonation supernova by studying a “cosmic bubble” — known as a supernova remnant — called SNR 0509-67.5. It’s 23 light-years across and expanding at over 11 million miles per hour. It’s previously been imaged by NASA’s Hubble Space Telescope.

SNR 0509-67.5 is in the Large Magellanic Cloud, a dwarf galaxy that orbits the Milky Way about 160,000 light-years distant in the constellation Dorado. SNR 0509-67.5 is Type Ia supernovae, which are known to produce iron on Earth, including in blood. Understanding these explosions of white dwarf stars is critical to astronomers who use them to measure distances in space.

How A Supernova Exploded Twice

SNR 0509-67.5 is a Type Ia supernova, the result of two stars orbiting each other. One, a white dwarf star — the dense core of a dead sun-like star — sucks matter onto its surface from the other star until a thermonuclear explosion occurs. The new discovery of a double-detonation supports the theory that, in at least some Type Ia supernovae, the white dwarf can be covered by a bubble of helium that, when it ignites, causes a shockwave that triggers a second detonation in the core of the star.

Astronomers predicted that if a double detonation had occurred, the remnant of the supernova would contain two separate shells of calcium. That’s exactly what was observed using the European Southern Observatory’s Very Large Telescope in Chile. The discovery was published today in Nature Astronomy.

Hubble Spots A Supernova

Earlier this year, NASA’s Hubble Space Telescope imaged a supernova about 600 million light-years away in the constellation Gemini. Visible as a blue dot at the center of the image above, supernova SN 2022aajn is also a Type Ia supernova. Exactly these types of supernovae are useful for astronomers because they all have the same intrinsic luminosity. That means they can be used as beacons to measure the distance to faraway galaxies.

ForbesA ‘New Star’ Suddenly Got 3 Million Times Brighter — How To See ItBy Jamie Carter

Background

Although they fall into the category of smaller explosions called a nova, two exploding stars are currently visible in the night sky. V572 Velorum, in the constellation Vela and V462 Lupi, in the constellation Lupus — only visible from the Southern Hemisphere — are currently shining millions of times brighter than usual.

Later this year or next year, if predictions are correct, a star in the Northern Hemisphere called T Coronae Borealis (T CrB and “Blaze Star”) in the constellation Corona Borealis will explode and become visible to the naked eye for several nights. This star system, about 3,000 light-years away, is a recurrent nova, meaning it experiences predictable eruptions. The last time T CrB brightened noticeably was in 1946.

Wishing you clear skies and wide eyes.

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Many medically relevant genes reside in “dark regions” of the genome that have long been elusive. To address this, we developed Paraphase – a computational tool that accurately resolves and analyzes paralogous genes. By unlocking the difficult-to-analyze regions of the genome where paralogous genes reside, Paraphase provides deeper insights into genetic variation, disease mechanisms and population diversity. This knowledge helps lay the groundwork for improved diagnostics, more inclusive reference genomes and future discoveries in genomic medicine. This multi-institutional study, led by PacBio, was published in Nature Communications.

Shedding light on the genome’s dark regions

We wanted to overcome a longstanding challenge in genomics: highly similar paralogous genes. These genes often reside within segmental duplications (SDs), which are large, repeated regions of DNA with nearly identical sequences. The repetitiveness of SDs complicates variant calling and copy number analysis, meaning traditional short-read sequencing technologies struggle to resolve these regions, leaving many genomic regions understudied and conditions undiagnosed.

To further our mission of accurately analyzing previously “dark” regions of the genome, we decided to design a tool for precise phasing and analysis of SDs with high accuracy and throughput. We also wanted to examine how copy number variations (CNVs) in certain paralogous genes differ across ancestries, and to show how this affects disease risk for different populations of people. We wanted to prove further how understanding genetic diversity such as copy numbers is key for building inclusive reference genomes and advancing equitable genomic medicine.

Paraphase uncovers genetic variations in segmental duplications in global populations

We developed a computational tool, Paraphase, to resolve segmental duplications (SDs) and allow us to accurately assess paralogs and copy numbers.

Before applying Paraphase to new data, we first validated the tool by applying it to known positive pathogenic samples and confirmed its accuracy. We then extended our analysis to 160 SD regions, spanning 316 genes. Samples came from 259 individuals across 5 ancestral groups: South Asian, European, African, Latin American and East Asian; the goal was to identify patterns of population-specific diversity and potential reference genome errors. Additionally, we examined 36 parent–offspring trios to detect de novo variants and gene conversion events.

The key findings of the study were:

• Paraphase enabled the analysis of medically important genes and associated diseases, such as those implicated in spinal muscular atrophy (SMN1/SMN2) and congenital adrenal hyperplasia (CYP21A2).
• We observed high copy number variability in many gene families within segmental duplications across people of different ancestries.
• We discovered a new approach for identifying false duplications in the reference genome.
• We identified 23 paralog groups with exceptionally low genetic diversity between genes and paralogs, indicating that frequent gene conversion and unequal crossing-over may contribute to similar gene copies.

Diverse genomic insights improve disease research and diagnosis

Our study demonstrates that using long-read HiFi sequencing in conjunction with our computational tool, Paraphase, provides a much richer and more detailed picture of genetic variation, specifically in complex SDs. By improving our ability to call disease-linked variants that are often missed by other technologies, Paraphase opens up new avenues for disease research.

For example, using Paraphase, we disentangled medically important gene families in a single test that have previously required specialized, multi-step assays. In the CYP21A2/CYP21A1P region – where mutations cause congenital adrenal hyperplasia – we characterized a previously overlooked duplication allele carrying both a functional CYP21A2 copy and a nonfunctional CYP21A2(Q319X) copy. Using standard tests, this duplication allele could easily have been misclassified.

Our study further highlights the power of long-read sequencing in detecting de novo variations, particularly in previously inaccessible parts of the genome. We uncovered seven previously undetected de novo single nucleotide variants (SNVs) and four de novo gene conversion events, two of which were non-allelic – a level of detail not possible with traditional sequencing approaches.

Additionally, our approach revealed high variation in copy number distributions across paralog groups in different ancestries. This finding reinforces the need for more genetically diverse reference genomes, as current references genomes are often biased toward European populations.

Paraphase provides a method for studying paralogous genes at scale, offering new opportunities for disease research, population-wide analysis and potentially even clinical testing. By broadening our understanding of genetic variation across ancestries, we can better understand how certain diseases impact specific populations, paving the way for more targeted diagnoses and treatment approaches.

By enabling more accurate identification of de novo variants and gene conversion events, our approach provides deeper insights into how genetic disorders arise and how traits are inherited. These discoveries offer a clearer view of genetic inheritance patterns and help reveal the underlying mechanisms of disease.

It should be noted that the current study focuses exclusively on gene families with fewer than 10 genes. Larger and more complex gene families were not included, meaning some medically important regions have yet to be studied. Additionally, the study is limited to assessing DNA-level variation in paralogs and does not explore transcriptomic or epigenetic factors, such as RNA expression or methylation differences between gene copies.

A broader lens: From genomics to multiomics

Looking ahead, we would like to extend Paraphase to study larger gene families, which were excluded from the current study. We’re also interested in applying Paraphase to investigate RNA-level differences and the transcriptional activity of paralogs that are very similar in sequence. It would be beneficial to explore epigenetic regulation with Paraphase, as it could provide further insights into how paralogous genes are controlled and expressed.

Reference: Chen X, Baker D, Dolzhenko E, et al. Genome-wide profiling of highly similar paralogous genes using HiFi sequencing. Nat Commun. 2025;16(1):2340. doi:10.1038/s41467-025-57505-2 

Topline

Just days after a nova appeared in the night sky, another joined it. V572 Velorum, in the constellation Vela, joins V462 Lupi in Lupus. Both are now visible to the naked eye to observers in the Southern Hemisphere and are currently shining millions of times brighter than usual. The remarkable coincidence — judged to be extremely rare by astronomers — has occurred as astronomers await the explosion of T Coronae Borealis (T CrB) in Corona Borealis, which is known to explode and shine brightly every 80 years or so.

Key Facts

How Rare Are Nova Explosions?

Astronomers estimate that between 20 and 50 novae occur each year in our galaxy, but most go undiscovered, according to NASA. Very few — typically zero — are visible to the naked eye. For two to appear at once is unprecedented. “This is without question an extremely rare event,” said Stephen O’Meara, an American astronomer, to Spaceweather.com. “I have yet to find an occurrence of two simultaneous nova appearing at the same time.”

Why V572 Velorum Is Getting Brighter

It’s thought that both V572 Velorum and V462 Lupi are both classical novas. A classical nova occurs when a white dwarf — the dense core of a collapsed sun-like star — is orbited by a larger star. According to NASA, the white dwarf’s gravity pulls hot hydrogen from its companion, which builds up and triggers a thermonuclear blast. Unlike supernovas, which obliterate stars, novas are recurring events that only affect the outer layer of a white dwarf. These outbursts can make the system millions of times brighter.

Novas Create Lithium (and The Solar System)

Lithium is used to make lithium batteries and lithium-ion batteries, as well as heat-resistant glass and ceramics and mood-altering chemicals. Most of the lithium in our solar system and the wider Milky Way galaxy comes from classical nova explosions like V572 Velorum and V462 Lupi, according to a paper published in 2020. The same researchers previously discovered that novas contributed to the molecular cloud that formed the solar system.

Further Reading

ForbesA ‘New Star’ Suddenly Got 3 Million Times Brighter — How To See ItBy Jamie CarterForbesA New Star Will Soon Appear — What To Know About T Coronae BorealisBy Jamie CarterForbesSee The First Jaw-Dropping Space Photos From Humanity’s Biggest-Ever CameraBy Jamie Carter

The aptly-named Bullet Cluster is a huge structure in deep space that formed from the merging of two massive galaxy clusters 3.8 billion lightyears away.

Now the James Webb Space Telescope has given scientists the clearest, most detailed look yet at the chaotic aftermath, including the location of the elusive dark matter hiding within it.

Solving just what dark matter is made of is one of the biggest goals in physics right now.

And Webb has given scientists an insight into how it’s distributed across this enormous region of space.

A crash course in cosmic cartography

The Bullet Cluster is not just two galaxy clusters colliding in slow-motion over billions of years, it’s also a physics lab for studying dark matter.

Dark matter is a mysterious substance that doesn’t emit or reflect light, but makes up most of the Universe’s mass.

Astronomers know it’s there because it’s the only way to account for the gravitational pull that’s holding galaxies together.

Counting up all the mass of visible matter in galaxies alone – stars, dust and gas – doesn’t reveal enough ‘stuff’ that could prevent a galaxy’s stars from flying outwards into space as the galaxy rotates.

There must be some extra, unseen matter holding the galaxy’s structure together. That unseens substance is known as ‘dark matter’.

A team of astronomers led by PhD student Sangjun Cha of Yonsei University have used Webb’s near-infrared vision to weigh and map the mass of the Bullet Cluster more accurately than ever before.

Their study, published in The Astrophysical Journal Letters, includes the most comprehensive gravitational lensing dataset of this region to date.

Seeing the invisible

We can’t directly see dark matter, but we can see its effects.

That’s where gravitational lensing comes in, a trick where massive objects like galaxy clusters bend and magnify the light from background galaxies.

It’s like watching light ripple across a pond, except in this case, the ripples are caused by dark matter warping spacetime.

“With Webb’s observations, we carefully measured the mass of the Bullet Cluster with the largest lensing dataset to date, from the galaxy clusters’ cores all the way out to their outskirts,” says Sangjun Cha.

“Webb’s images dramatically improve what we can measure in this scene, including pinpointing the position of invisible particles known as dark matter,” says Kyle Finner, a study co-author and an assistant scientist at IPAC at Caltech in Pasadena, California.

Tracing the stars between galaxies

The team measured thousands of galaxies in Webb’s images to accurately ‘weigh’ visible and invisible mass in the galaxy clusters.

And they mapped and measured the light emitted by stars no longer bound to individual galaxies, known as intracluster stars.

Their findings are persuasive:. “We confirmed that the intracluster light can be a reliable tracer of dark matter, even in a highly dynamic environment like the Bullet Cluster,” Cha says.

What’s more, if these stars are bound to cluster’s dark matter, the team say it could get easier to refine what they know about dark matter.

In the new map of the Bullet Cluster, an image from Webb’s NIRCam (Near-Infrared Camera) is overlaid with data from NASA’s Chandra X-ray Observatory.

It shows hot gas in pink, including the bullet shape on the right side of the image.

Refined measurements of the dark matter, calculated by the team using Webb, are shown in blue.

Viewed as a whole, the new measurements refine the map of mass spread across the Bullet Cluster.

And this is revealing the history of the clusters involved in the merger.

For example, the galaxy cluster on the left of the image has an asymmetric, elongated area of mass along the left edge of the blue region.

This, say the team, is a clue pointing to previous mergers in that cluster.

A dark, mysterious giant

The team’s study shows that dark matter isn’t just invisible, it’s eerily quiet.

Their observations confirm it doesn’t interact much, if at all, with itself. Or, as the study puts it: “dark matter shows no signs of significant self-interaction”.

“As the galaxy clusters collided, their gas was dragged out and left behind, which the X-rays confirm,” Finner says.

Webb’s observations show dark matter still lines up with the galaxies, and wasn’t dragged away.

The bullet that shot twice

The dark matter map also suggests the Bullet Cluster may have gone through more than one dramatic collision.

That mass clump on the left could be the fingerprint of an earlier, or later, collision involving the larger cluster.

“A more complicated scenario would lead to a huge asymmetric elongation like we see on the left,” says James Jee, co-author and professor at Yonsei University.

What’s next?

The team say they’ve only uncovered part of the story.

“It’s like looking at the head of a giant,” says Jee. “Webb’s initial images allow us to extrapolate how heavy the whole ‘giant’ is, but we’ll need future observations of the giant’s whole ‘body’ for precise measurements.”

Enter the Nancy Grace Roman Space Telescope, scheduled to launch by May 2027, which will also give researchers expansive near-infrared images of the Universe.

“From NASA’s Nancy Grace Roman Space Telescope, which is set to launch by May 2027. “”With Roman, we will have complete mass estimates of the entire Bullet Cluster, which would allow us to recreate the actual collision on computers,” Finner says.

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A new technology that uses clinical MRI machines to image metabolic activity in the brain could give researchers and clinicians unique insight into brain function and disease, researchers at the University of Illinois Urbana-Champaign report. The non-invasive, high-resolution metabolic imaging of the whole brain revealed differences in metabolic activity and neurotransmitter levels among brain regions; found metabolic alterations in brain tumors; and mapped and characterized multiple sclerosis lesions — with patients only spending minutes in an MRI scanner.

Led by Zhi-Pei Liang, a professor of electrical and computer engineering and a member of the Beckman Institute for Advanced Science and Technology at the U. of I., the team reported its findings in the journal Nature Biomedical Engineering.

“Understanding the brain, how it works and what goes wrong when it is injured or diseased is considered one of the most exciting and challenging scientific endeavors of our time,” Liang said. “MRI has played major roles in unlocking the mysteries of the brain over the past four decades. Our new technology adds another dimension to MRI’s capability for brain imaging: visualization of brain metabolism and detection of metabolic alterations associated with brain diseases.”

Conventional MRI provides high-resolution, detailed imaging of brain structures. Functional MRI maps brain activity by detecting changes in blood flow and blood oxygenation level, which are closely linked to neural activity. However, they cannot provide information on the metabolic activity in the brain, which is important for understanding function and disease, said postdoctoral researcher Yibo Zhao, the first author of the paper.

“Metabolic and physiological changes often occur before structural and functional abnormalities are visible on conventional MRI and fMRI images,” Zhao said. “Metabolic imaging, therefore, can lead to early diagnosis and intervention of brain diseases.”

Both MRI and fMRI techniques are based on magnetic resonance signals from water molecules. The new technology measures signals from brain metabolites and neurotransmitters as well as water molecules, a technique known as magnetic resonance spectroscopic imaging. These MRSI images can provide significant new insights into brain function and disease processes, and could improve sensitivity and specificity for the detection and diagnosis of brain diseases, Zhao said.

Other attempts at MRSI have been bogged down by the lengthy times required to capture the images and high levels of noise obscuring the signals from neurotransmitters. The new technique addresses both challenges.

“Our technology overcomes several long-standing technical barriers to fast high-resolution metabolic imaging by synergistically integrating ultrafast data acquisition with physics-based machine learning methods for data processing,” Liang said. With the new MRSI technology, the Illinois team cut the time required for a whole brain scan to 12 and a half minutes.

The researchers tested their MRSI technique on several populations. In healthy subjects, the researchers found and mapped varying metabolic and neurotransmitter activity across different brain regions, indicating that such activity is not universal. In patients with brain tumors, the researchers found metabolic alterations, such as elevated choline and lactate, in tumors of different grades — even when the tumors appeared identical on clinical MRI images. In subjects with multiple sclerosis, the technique detected molecular changes associated with neuroinflammatory response and reduced neuronal activity up to 70 days before changes become visible on clinical MRI images, the researchers report.

The researchers foresee potential for broad clinical use of their technique: By tracking metabolic changes over time, clinicians can assess the effectiveness of treatments for neurological conditions, Liang said. Metabolic information also can be used to tailor treatments to individual patients based on their unique metabolic profiles.

“High-resolution whole-brain metabolic imaging has significant clinical potential,” said Liang, who began his career in the lab of the late Illinois professor Paul Lauterbur, recipient of the Nobel Prize for developing MRI technology. “Paul envisioned this exciting possibility and the general approach, but it has been very difficult to achieve his dream of fast high-resolution metabolic imaging in the clinical setting.

“As healthcare is moving towards personalized, predictive and precision medicine, this high-speed, high-resolution technology can provide a timely and effective tool to address an urgent unmet need for noninvasive metabolic imaging in clinical applications.”

Reference: Zhao Y, Li Y, Jin W, et al. Ultrafast J-resolved magnetic resonance spectroscopic imaging for high-resolution metabolic brain imaging. Nat Biomed Eng. 2025. doi: 10.1038/s41551-025-01418-4

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Topline

The Northern Lights may be visible in the U.S. overnight on Wednesday and Thursday just as the Milky Way appears in the night sky. The delayed arrival of a coronal mass ejection traveling towards Earth may cause a geomagnetic storm, according to the latest forecast by the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center. It follows a false alarm on July 1-2, but also notable displays of aurora in northern U.S. states in recent weeks.

Key Facts

Where To See The Northern Lights

NOAA’s aurora viewlines indicate potential aurora displays are possible in northern U.S. states and Canada. U.S. states that may see aurora include (northerly parts of) Washington, northern Idaho, Montana, Wyoming, North Dakota, South Dakota, Minnesota, Wisconsin, Michigan, Iowa, New York, Vermont, New Hampshire and Maine. In the U.S., regions close to the Canadian border will have the highest chance.

When To See The Northern Lights

When and where aurora is visible is uncertain until a turbulent solar wind is detected by NASA’s DSCOVR and ACE satellites. Orbiting the sun from around a million miles from Earth, they give a roughly 30-minute warning of aurora displays after measuring the solar wind’s speed and magnetic intensity. Check NOAA’s 30-minute forecast or use the Glendale App for up-to-the-minute forecasts. Be prepared to fail — it may take multiple trips to finally see aurora, as displays can be unpredictable.

The Milky Way In June

Early July is a great time to see the Milky Way. Although it’s visible from the Northern Hemisphere all year, its bright core only becomes visible in the southern sky after dark from late May through September. The bright core is the center of the galaxy, home to a dense concentration of stars, star clusters and nebulae. You’ll need to be away from light pollution to see it.

Further Reading

ForbesBootid Meteor Shower: How To See ‘Shooting Stars’ On FridayBy Jamie CarterForbesA Comet 85 Miles Wide Is Erupting In The Solar System — What To KnowBy Jamie CarterForbesNASA Urges Public To Leave The City As Milky Way Appears — 15 Places To GoBy Jamie Carter

The study, published in Royal Society Open Science, found chlorothalonil – one of the world’s most extensively used fungicides – severely impacts insect reproduction and survival, even at the lowest levels routinely detected on food.

“Even the very lowest concentration has a huge impact on the reproduction of the flies that we tested,” says lead author Darshika Dissawa, a PhD candidate from Macquarie’s School of Natural Sciences.

“This can have a big knock-on population impact over time because it affects both male and female fertility.”

The researchers exposed fruit flies (Drosophila melanogaster) to chlorothalonil levels matching those typically found in produce from cranberries to wine grapes. Even at the lowest dose, flies showed a 37 percent drop in egg production compared with unexposed individuals.

Chlorothalonil is a widely applied broad-spectrum fungicide in American agriculture, used on crops like:

• Tomatoes
• Potatoes
• Peanuts
• Corn
• Turfgrass (e.g., golf courses)
• Fruits such as peaches, strawberries, and melons

Supervising author Associate Professor Fleur Ponton says the dramatic decline was unexpected.

“We expected the effect to increase far more gradually with higher amounts. But we found that even a very small amount can have a strong negative effect,” Associate Professor Ponton says.

Although banned in the European Union, chlorothalonil is extensively applied to Australian crops including orchards and vineyards, often preventatively when no disease is present.

The findings add to mounting evidence of global insect population decline, with some regions reporting drops exceeding 75 percent in recent decades.

“We need bees and flies and other beneficial insects for pollination, and we think this is an important problem for pollinator populations,” Associate Professor Ponton says.

The research highlights a critical knowledge gap in pesticide regulation, with fewer than 25 scientific papers examining chlorothalonil’s effects on insects despite its widespread use.

The researchers recommend more sustainable practices, including reduced application frequency to allow insect population recovery between treatments.

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The new weather satellite Meteosat Third Generation Sounder-1 (MTG-S1) lifted off on board a Falcon 9 rocket from the US company SpaceX on Tuesday. It is expected to provide more precise weather forecasting.

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An instrument for monitoring air pollution was also launched into space together with the satellite from the Kennedy Space Centre in Florida. The European Space Agency (Esa) announced that the launch had been successful.

The spacecraft, developed by Esa on behalf of weather satellite operator Eumetsat, will “revolutionise weather forecasting and climate observation in Europe”, said Tobias Guggenmoser from Esa. As an Eumetsat member, Switzerland will also utilise the satellite’s data.

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Swiss satellite tech to improve weather forecasting from space

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Aug 23, 2018


The Aeolus satellite, which is carrying Swiss technology, will measure winds around the globe.

Read more: Swiss satellite tech to improve weather forecasting from space

The infrared sounder will collect data on temperature, humidity and trace gases at an altitude of around 36,000 kilometres. This can help to recognise and predict rapidly developing and potentially dangerous weather patterns. “By recording 1,700 infrared channels every half hour, we can slice the sky into layers (…) so that meteorologists can see exactly what is happening at every altitude,” explained Guggenmoser.

The satellite, whose main contractor is the company OHB Bremen, is a major step forward for Esa. Europe previously only had imagers, which are satellites with imaging instruments, but not sounders with spectroscopic instruments for geostationary weather satellites.

More precise warnings, more protection, less damage

Before MTG-S1 lifted off into space, an imager from the satellite series had already been launched into space. Another is due to follow next year to complete the constellation. Together, these three instruments should be able to see the formation of thunderstorms before clouds even form and thus provide more precise storm warnings. The hope is that communities will be able to better prepare for severe storms in the future, resulting in less damage and fewer deaths.

The newly launched missile also carries the Sentinel-4 satellite of the Copernicus Atmospheric Monitoring Service (CAMS) for monitoring air quality. The instrument analyses the composition of the atmosphere, for example with regard to ozone and nitrogen dioxide, and is intended to provide more precise information on air pollution in Europe. Switzerland does not use the data from the Copernicus satellite as it is not a member.

Translated from German by DeepL/jdp