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Astronomers Spot White Dwarf Star Creating a Colorful Shockwave

The central square image, taken with the MUSE instrument on ESO's Very Large Telescope, shows shock waves around the dead star RXJ0528+2838. (European Southern Observatory (ESO)/K. Ilkiewicz and S. Scaringi et al./Handout via Reuters)
The central square image, taken with the MUSE instrument on ESO's Very Large Telescope, shows shock waves around the dead star RXJ0528+2838. (European Southern Observatory (ESO)/K. Ilkiewicz and S. Scaringi et al./Handout via Reuters)
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Astronomers Spot White Dwarf Star Creating a Colorful Shockwave

The central square image, taken with the MUSE instrument on ESO's Very Large Telescope, shows shock waves around the dead star RXJ0528+2838. (European Southern Observatory (ESO)/K. Ilkiewicz and S. Scaringi et al./Handout via Reuters)
The central square image, taken with the MUSE instrument on ESO's Very Large Telescope, shows shock waves around the dead star RXJ0528+2838. (European Southern Observatory (ESO)/K. Ilkiewicz and S. Scaringi et al./Handout via Reuters)

Astronomers have observed a white dwarf - a highly compact Earth-sized stellar ember - that is creating a colorful shockwave as it moves through space, leaving them searching for an explanation.

The highly magnetized white dwarf is gravitationally bound to another star in what is called a binary system. The white dwarf is siphoning gas from its companion as the two orbit close to each other. The system is located in the Milky Way about 730 light-years from Earth - relatively nearby in cosmic terms - in the constellation Auriga.

A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).

The shockwave - more specifically a bow shock - caused by the white dwarf was observed using the European Southern Observatory's Chile-based Very Large Telescope. The shockwave was seen in an image released by the scientists glowing in various colors produced when material flowing outward from the white dwarf collided with interstellar gas.

"A shockwave ‌is created when ‌fast-moving material plows into surrounding gas, suddenly compressing and heating it. A ‌bow shock ⁠is the curved ‌shock front that forms when an object moves rapidly through space, similar to the wave in front of a boat moving through water," said astrophysicist Simone Scaringi of Durham University in England, co-lead author of the study published on Monday in the journal Nature Astronomy.

"The colors come from interstellar gas that is being heated and excited by the shock. Different chemical elements glow at specific colors when this happens," Scaringi added.

In this shockwave, a red hue represented hydrogen, green represented nitrogen and blue represented oxygen residing in interstellar space.

A handful of other white dwarfs have been observed creating shockwaves. But all of those were ⁠surrounded by disks of gas siphoned from a binary partner. Although this white dwarf is siphoning gas from its companion, it lacks any such disk and ‌is releasing gas into space for unknown reasons.

White dwarfs are among the ‍universe's most compact objects, though not as dense as ‍black holes.

Stars with up to eight times the mass of the sun appear destined to end up as ‍a white dwarf. They eventually burn up all the hydrogen they use as fuel. Gravity then causes them to collapse and blow off their outer layers in a "red giant" stage, eventually leaving behind a compact core - the white dwarf.

"There are plenty of white dwarfs out there, as these are the most common endpoints of stellar evolution," Scaringi said.

The sun appears fated to end its existence as a white dwarf, billions of years from now.

This white dwarf has a mass comparable to the sun contained in a body slightly larger than Earth. Its binary companion is ⁠a type of low-mass star called a red dwarf that is about a tenth the mass of the sun and thousands of times less luminous. It orbits the white dwarf every 80 minutes, with the two extremely close to each other - approximately the distance between the moon and Earth.

The gravitational strength of the white dwarf is pulling gas off the red dwarf. This siphoned material is being pulled into the white dwarf along its strong magnetic field, eventually landing at its magnetic poles. While this process releases energy and radiation, it cannot account for the outflow of material needed to produce the observed shockwave, Scaringi said.

"Every mechanism with outflowing gas we have considered does not explain our observation, and we still remain puzzled by this system, which is why this result is so interesting and exciting," Scaringi said.

"The shape and length of the (shockwave) structure show that this process has been ongoing for at least about 1,000 years, making it long-lived rather than a one-off event," Scaringi added.

The ‌researchers took note of the aesthetics of the colorful shockwave.

"Beyond the science, it's a striking reminder that space is not empty or static as we may naively imagine it: it's dynamic and sculpted by motion and energy," Scaringi said.

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Varieties

The Milky Way Devoured Smaller Galaxy About 11.8 Billion Years Ago

The collision about 11.8 billion years ago, when a dwarf galaxy known as LKH collided with the Milky Way and merged with it, appears in an artist's concept released on August 17, 2026. NASA, ESA, Joseph Olmsted (STScI)/Handout via REUTERS
The collision about 11.8 billion years ago, when a dwarf galaxy known as LKH collided with the Milky Way and merged with it, appears in an artist's concept released on August 17, 2026. NASA, ESA, Joseph Olmsted (STScI)/Handout via REUTERS
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The Milky Way Devoured Smaller Galaxy About 11.8 Billion Years Ago

The collision about 11.8 billion years ago, when a dwarf galaxy known as LKH collided with the Milky Way and merged with it, appears in an artist's concept released on August 17, 2026. NASA, ESA, Joseph Olmsted (STScI)/Handout via REUTERS
The collision about 11.8 billion years ago, when a dwarf galaxy known as LKH collided with the Milky Way and merged with it, appears in an artist's concept released on August 17, 2026. NASA, ESA, Joseph Olmsted (STScI)/Handout via REUTERS

The Milky Way, a large and spiral-shaped galaxy that is home to hundreds of billions of stars including our sun, has taken a long and complicated path to achieve its current dimensions, as illustrated by new research documenting a milestone event early in its history.

Scientists observing clusters of stars congregated near the Milky Way's center have discovered evidence that our galaxy swallowed a smaller galaxy roughly 11.8 billion years ago, when the universe was less than 15% of its current age. The event represents the Milky Way's earliest-known galactic merger and shows how it grew not only by forming its own stars but by merging with smaller galaxies caught in its gravitational pull.

The smaller galaxy is classified as a dwarf galaxy, differentiating it from larger galaxies like the Milky Way. The researchers estimate that it contained stars with a mass equivalent to 500 million times that ⁠of the sun ⁠at the time of the merger, about a quarter the size of what the Milky Way was at the time.

The researchers used the orbiting Hubble and Gaia telescopes to study stellar clusters, each containing hundreds of thousands of stars, inhabiting a region spanning the Milky Way's innermost 20,000 light-years, gauging their age, chemical composition and trajectory. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).

These stars became part of the Milky Way after a galactic merger that occurred about 2 billion years after the Big Bang event that initiated the ⁠universe, they said. The dwarf galaxy where they originated was given the name Low-energy-Kraken-Heracles, or LKH, in recognition of three earlier studies that examined the possibility of such a primordial merger.

"The key finding of our research is the unambiguous discovery of the first merger event experienced by our galaxy in its infancy," said astrophysicist Davide Massari of the National Institute for Astrophysics, or INAF, in Bologna, Italy, lead author of the study published in the journal Nature Astronomy.

Whether the Milky Way's early growth was fueled by homegrown star formation or a galactic merger has been a matter of debate, Reuters quoted Massari as saying. The new study indicates that the merger infused the Milky Way early in its history with a large volume of stars and interstellar gas that feeds star formation, as well as the mysterious substance called dark matter.

"I would say that from the point of view of stars, the merger ⁠was rather peaceful, with ⁠no star-to-star crashes. But from the point of view of the gas, the merger was more 'explosive' — likely, the collision between the gas from LKH and that from the Milky Way triggered the formation of many stars," Massari said.

Massari said there are probably many stars that originally formed in the dwarf galaxy that still are buried in the inner regions of the Milky Way, some of them inside stellar clusters. Because of all the interstellar dust in this region, however, it is very difficult to identify individual stars, Massari said.

The Milky Way is known to have been involved in two other massive galactic mergers. It absorbed a dwarf galaxy called Gaia-Sausage-Enceladus about 1.8 billion years after the LKH merger. And over the past approximately 6 billion years it has been combining with the Sagittarius dwarf galaxy.

"Every single one of these mergers had an influence on the events that have led to the formation of our own solar system, and ultimately of Earth," Massari said. "This is why I think that reconstructing the pieces of the Milky Way's past effectively contributes to answering the big question about, 'Where do we come from?'"

Varieties

Flight Attendants and Pilots Have Highest Risk of Dying from Radiation-Linked Cancers, Study Says

American Airlines flight 718, the first US Boeing 737 MAX commercial flight since regulators lifted a 20-month grounding in November, lands at LaGuardia airport in New York, US, December 29, 2020. (Reuters)
American Airlines flight 718, the first US Boeing 737 MAX commercial flight since regulators lifted a 20-month grounding in November, lands at LaGuardia airport in New York, US, December 29, 2020. (Reuters)
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Flight Attendants and Pilots Have Highest Risk of Dying from Radiation-Linked Cancers, Study Says

American Airlines flight 718, the first US Boeing 737 MAX commercial flight since regulators lifted a 20-month grounding in November, lands at LaGuardia airport in New York, US, December 29, 2020. (Reuters)
American Airlines flight 718, the first US Boeing 737 MAX commercial flight since regulators lifted a 20-month grounding in November, lands at LaGuardia airport in New York, US, December 29, 2020. (Reuters)

Flight attendants and pilots are at the highest risk of dying from radiation-related cancers — even more than people who work with radioactive materials, according to a new study.

Cosmic radiation comes from space. Only a small amount reaches the Earth's surface, but exposure is greater for people flying at high altitudes.

There’s been limited evidence from small studies suggesting that the exposure translates to higher cancer death rates among people who fly often, particularly pilots and flight attendants. The new study “brings important new evidence to bear on this question,” two Australian radiation experts who weren't involved in the research wrote in an accompanying commentary.

The latest study, published Monday by JAMA Internal Medicine, used national data from more than 12 million death certificates that included information about occupations. The authors looked at death rates from cancers that are tied to radiation exposures, including leukemia, lymphoma, multiple myeloma, and cancers of the skin, breast, thyroid, prostate and central nervous system.

Among more than 500 occupations, flight attendants had the highest percentage of deaths from radiation-related cancers, and pilots were second, the researchers found. For those two occupations, the odds of dying were unusually high for each type of radiation-related cancer.

Neither group showed higher-than-normal death rates from cancers that aren't tied to radiation exposure, noted the commentary writers, Catherine Olsen and Ken Karipidis. That fact “supports the hypothesis that occupational radiation exposure, rather than lifestyle or socioeconomic factors, underlies the observed excess,” they wrote.

The researchers found that flight attendants had about 50% higher odds of dying from a radiation-related cancer than the general working population, and pilots had about 36% higher odds.

In terms of absolute risk, about 6.9% of flight attendant deaths were from these cancers — roughly 1 in 14. Among pilots, it was 6.7%. For the general working population, it was 5%, said the study's first author, Dr. Vishal Patel of Harvard Medical School.

The authors acknowledged some limitations in their study. They do not know how much exposure each flight attendant and pilot got in the air or from other sources. It's also possible occupations were misclassified on some death certificates.

They also could not account for another possible contributor specific to the professions: Cancer risk can be worsened by frequent disruption of the body’s internal clock, which can be affected by jet lag, crossing time zones and irregular work schedules.

The Federal Aviation Administration has acknowledged that aircrews are exposed to ionizing radiation, but the government does not set federal dose limits or require monitoring, the authors noted.

“You can't manage an exposure you've decided not to measure,” Patel said in an email.

Sara Nelson, who leads a union representing 55,000 flight attendants, said the report reinforces that radiation exposure needs to be taken seriously, as the union has suggested for years.

“The risk is known, but crew are not educated or informed. And, no one is taking responsibility,” said Nelson, president of the Association of Flight Attendants-CWA.

Annual skin examinations may be warranted for all people working on high-altitude flights, and women in those jobs may want to get mammograms earlier or more frequently, Olsen and Karipidis wrote. Doctors who care for pilots and flight attendants also should have a “heightened index of suspicion” for cancer when evaluating these patients, they said.

Varieties

Misk Foundation and UN Youth Office Announce Establishment of Global Network for Youth

The network is the first platform of its kind established by Misk - SPA
The network is the first platform of its kind established by Misk - SPA
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Misk Foundation and UN Youth Office Announce Establishment of Global Network for Youth

The network is the first platform of its kind established by Misk - SPA
The network is the first platform of its kind established by Misk - SPA

The Mohammed bin Salman Foundation (Misk), in collaboration with the United Nations Youth Office, announced on Tuesday the establishment of the Global Network for Youth, a new international network connecting independent global organizations working to serve youth with leadership and policymaking pathways at the global level.

The announcement was made during the convening of the AFS Youth Assembly in Geneva, coinciding with International Youth Day.
The Global Network for Youth will be officially launched during the United Nations General Assembly in New York in September 2026, SPA reported.

The network is the first platform of its kind established by Misk in collaboration with the UN Youth Office, building on a partnership between the two dating back to 2018.

It brings together independent youth-focused organizations from different regions and provides tailored pathways enabling young people to participate in global policymaking and decision-making.

The network operates around four pillars: strengthening young people's capacities in public policy and advocacy; creating clear pathways to UN platforms and global forums; amplifying diverse youth voices and those of underrepresented groups; and equipping member organizations with tools, data, and shared knowledge.