Latest news with #Buzzo
Yahoo
19-04-2025
- Science
- Yahoo
Ghostly galaxy without dark matter baffles astronomers
When you buy through links on our articles, Future and its syndication partners may earn a commission. Astronomers have stumbled upon yet another ghostly galaxy that appears to be devoid of dark matter. Dark matter, the invisible substance astronomers believe dominates the universe, provides the gravitational scaffolding for galaxies to assemble and grow. Discovering a galaxy without dark matter is indeed perplexing, like finding a shadow without a source. Yet, over the past decade, several such sightings have been reported — all of them so-called "ultradiffuse galaxies," which are about the size of our own Milky Way but remarkably sparse in stars. The latest member of this puzzling collection, known as FCC 224, resides on the fringes of the Fornax Cluster, a collection of galaxies that lies roughly 65 million light-years from Earth. Related: What is dark matter? First spotted in 2024, FCC 224 is a dwarf galaxy that boasts a dozen luminous, tightly bound clusters of stars — an unusually rich population for its size, typically seen in larger, dark-matter rich galaxies — yet appears to lack the mysterious substance. It also occupies a distinctly different cosmic neighborhood than other galaxies that are deficient in dark matter, suggesting such objects might not be isolated flukes but rather represent a more common, previously unrecognized class of dwarf galaxies, according to two complementary papers published last month. "No existing galaxy formation model within our standard cosmological paradigm can currently explain how this galaxy came to be," Maria Buzzo, a doctoral candidate in astrophysics at the Swinburne University of Technology in Australia who led one of the new studies, said in a statement. Using data from the Keck Observatory in Hawaii, Buzzo and her team tracked the movement of a dozen star clusters within FCC 224. These measurements revealed a slow speed among the clusters, a key indicator that the galaxy lacks the strong gravitational pull expected from dark matter, the new study reports. No known scenario can fully explain FCC 224's properties, the researchers say. Another team, led by astronomer Yimeng Tang at the University of California, Santa Cruz, compared FCC 224's properties to other galaxies that seemingly lack dark matter, focusing on two ghostly objects within the NGC 1052 group about 65 million light-years away in the constellation Cetus. Tang and his colleagues propose that FCC 224, like those NGC 1052 dwarf galaxies, formed from a high-velocity collision of gas-rich galaxies. In such an event, the gas separates from the dark matter, and subsequent star formation in the expelled gas forms one or more dark-matter-free galaxies. Related stories: — Dark matter might live in a dense haze around stellar corpses — Dark matter could finally reveal itself through self-interactions — Keck Observatory: Twin telescopes on Mauna Kea Previous research found that the two galaxies in the NGC 1052 group, DF2 and DF4, belong to a trail of seven to 11 dark-matter-deficient galaxies that formed in the same ancient collision. FCC 224 likely has a twin galaxy, too, Tang and his team suggest in their study. One candidate is the nearby galaxy FCC 240, which appears to have the same size, shape and orientation as FCC 224. If forthcoming observations confirm the shared properties, it would provide crucial evidence supporting the collision scenario for the formation of FCC 224, the researchers say. Alternatively, FCC 224 could be the result of a chaotic, high-energy environment where intense star formation from overmassive star clusters expelled dark matter from the galaxy, the team suggests. "FCC 224 serves as a crucial data point in our effort to identify and study other dark-matter-deficient galaxies," Buzzo said in the statement. "By expanding the sample size, we can refine our understanding of these rare galaxies and of the role of dark matter in dwarf galaxy formation."
CBS News
31-03-2025
- Health
- CBS News
Electric vehicle fires spark new health fears for firefighters
Local doctors and researchers are studying how electric vehicles can pose long-term health issues for first responders. Claudine Buzzo has never responded to an EV fire, but she knows the health risks involved in firefighting. "I think a lot of people don't realize what we see on a daily basis," Buzzo said. She is a firefighter and the Benefits Officer for the Metro-Dade Firefighters Union. She's also a cancer survivor. "I wasn't feeling good. I went to the emergency room. They found a mass on my pancreas," Buzzo recalled. "It turns out it was a neuroendocrine tumor. It's a really rare tumor. Obviously, it was very shocking." After an intense 10-hour surgery and a 6-week hospital stay filled with complications, she returned to light duty. Then, last year—eight years after her first diagnosis—she was diagnosed with two types of breast cancer. "It was a punch to the gut again. I went through a lot with the pancreas, so my first call was to Dr. Kobetz, and she got me through to Sylvester." Sylvester Comprehensive Cancer Center is home to the Firefighter Cancer Initiative, which is currently leading a multidisciplinary study into electric vehicle fires and how they could impact firefighter health down the road. "The batteries that are located in there create a space for greater exposure to metals," said Dr. Alberto Caban-Martinez. Dr. Caban-Martinez says different metals emitted during an EV fire are linked to different types of cancer. For example, nickel—a key metal in EV batteries—is linked to lung, nasal, and laryngeal cancer. Chromium, which is found in some EV batteries, is associated with lung, nasal, and sinus cancer. "What we know from electric vehicle fires in an experiment we did that summer is that the plume of smoke contains really high concentrations of these metals, so the amount of exposure in one instance is much higher than you would see in a traditional combustion car," Dr. Caban-Martinez explained. We reached out to the Electric Vehicle Association for comment. A board member replied, writing in part, "Firefighters definitely have a risky job. Whether it is gas and oil in cars, asbestos from burning structures, lead in paint, or even rubber in tires, noxious fumes from any fire definitely pose a health risk. I think that's why a self-contained breathing apparatus is such an important part of any firefighter's job." The statement goes on to say, "It seems unlikely that lithium-ion batteries in EVs significantly increase on-the-job risk vis-à-vis other types of fire risk, but it appears the Miller School of Medicine's approach to this field of study is sound." Data from the National Transportation Safety Board shows electric vehicles are less of a fire risk than conventional combustion-engine cars, but firefighters know they present a unique challenge. "It's scary knowing the toxins that are coming out of these batteries," Buzzo said.
