Tag Archives: hints

New Research Hints That Our Milky Way May Avoid Collision with Andromeda Galaxy

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The Milky Way galaxy is often believed to be on a collision path with the neighboring Andromeda galaxy. This merger, anticipated roughly 5 billion years in the future, is expected to create a new elliptical galaxy. However, recent studies indicate that the likelihood of such a catastrophic event may be less than previously assumed.

These images depict three encounter scenarios between the Milky Way galaxy and the neighboring Andromeda galaxy. Top left: Messier 81 and Messier82. TopRight: NGC6786. BOTTOM: NGC 520. Image credits: NASA/ESA/STSCI/DSS/Till Sawala, Helsinki University/Joseph Depasquale, STSCI.

The Milky Way navigates through space, its trajectory affected by the gravitational forces from nearby galaxies, including Andromeda, Triangulum, and the Large Magellanic Cloud.

Consequently, prior studies have proposed for over a decade that the Milky Way is likely to collide with Andromeda, forming a new elliptical galaxy referred to as Milkomeda in about 5 billion years.

Dr. Thiru Sawara, an astronomer at the University of Helsinki, stated:

In their latest research, Dr. Sawara and colleagues utilized updated data from the ESA Gaia satellite and the NASA/ESA Hubble Space Telescope to model the Milky Way’s movement through space over the next 10 billion years, while also refining estimates of the masses of local galaxies.

They discovered that there is about a 50% chance that no collision will occur between the Milky Way and Andromeda during this time frame.

The authors suggest that previous analyses overlooked certain calculations and uncertainties, including the gravitational influence of the Large Magellanic Cloud (a smaller galaxy orbiting the Milky Way).

They also propose that a merger with the Magellanic Clouds is nearly certain within the next two billion years, prior to any potential interaction with Andromeda.

“Even with the latest and most precise observational data at hand, the future of local galaxy groups remains uncertain,” Dr. Sawara remarked.

“Interestingly, there are roughly equal probabilities of widely discussed merger scenarios or, conversely, scenarios where the Milky Way and Andromeda remain unaffected.”

The team’s findings will be featured this week in the journal Nature Astronomy.

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T. Sawara et al. There is no certainty regarding the Milky Way and Andromeda collision. Nature Astronomy. Published online on June 2, 2025. doi:10.1038/s41550-025-02563-1

Source: www.sci.news

Webb’s discovery of brown dwarf candidates hints at first wealthy population outside of the Milky Way

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope detected a population of 64 brown dwarf candidates with masses ranging from 50 to 84 Jupiter masses in the star cluster NGC 602.

This image of NGC 602 includes data from Webb's NIRCam (near-infrared camera) and MIRI (mid-infrared instrument) instruments. Image credits: NASA / ESA / CSA / Webb / P. Zeidler / E. Sabbi / A. Nota / M. Zamani, ESA & Webb.

NGC602 is a very young star cluster, about 200,000 light-years away in the constellation Hydra, about 2 to 3 million years old.

Also known as ESO 29-43, this star resides in the wings of the Small Magellanic Cloud.

NGC 602's local environment closely resembles that of the early Universe, with very low abundances of elements heavier than hydrogen and helium.

The presence of dark clouds of dense dust and the fact that the cluster is rich in ionized gas also suggests the presence of an ongoing star formation process.

Together with the associated HII region N90, which contains clouds of ionized atomic hydrogen, this cluster provides a rare opportunity to examine star formation scenarios under conditions dramatically different from those in the solar neighborhood.

Using Webb, Dr. Peter Zeidler and his colleagues at AURA and ESA were able to detect 64 brown dwarf candidates in NGC 602. This is the first rich population of brown dwarfs to exist outside the Milky Way.

“It is possible to detect objects at such great distances only with incredible sensitivity and spatial resolution in the right wavelength range,” Dr. Zeidler said.

“This has never been possible and will remain impossible from the ground for the foreseeable future.”

“So far, about 3,000 brown dwarfs are known, and they all live in our galaxy,” said Dr. Elena Mangiavakas, also from AURA and ESA.

“This discovery highlights the ability to use both Hubble and Webb to study young star clusters,” said Dr. Antonella Nota, executive director of the International Space Science Institute.

“Hubble showed that NGC 602 hosts very young, low-mass stars, but only Webb can conclusively confirm the extent and significance of substellar mass formation in this cluster. Hubble and Webb are an amazingly powerful telescope duo!”

“Our results are very consistent with the theory that the mass distribution of objects below the hydrogen burning limit is simply a continuation of the stellar distribution,” Dr. Zeidler said.

“They seem to form the same way, they just haven't accumulated enough mass to become full stars.”

NSF astronomer Dr. Elena Sabbi said, “Studying the newly discovered metal-poor young brown dwarfs in NGC 602 will shed light on how stars and planets formed under the harsh conditions in the early universe. We are getting closer to uncovering the secrets of this.” NOIRLab, University of Arizona, Space Telescope Science Institute.

“These are the first substellar objects outside the Milky Way,” Manjavakas said.

“We need to be prepared for new breakthrough discoveries in these new objects.”

of result will appear in astrophysical journal.

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peter zeidler others. 2024. A candidate for a subsolar metallic brown dwarf is discovered in the Small Magellanic Cloud. APJ 975, 18; doi: 10.3847/1538-4357/ad779e

Source: www.sci.news

The distinctive chemical makeup of adolescent perspiration includes hints of musk and urine aromas

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Body odor usually worsens around puberty

Carlos Barquero/Alamy

Teens appear to produce chemicals in their sweat that cause body odor, such as urine, musk, and sandalwood. Awareness of these chemicals may lead to more effective odor control measures, such as more effective deodorants.

Because the chemical compounds in sweat are volatile, they easily turn into gases that are perceived as odor. Hormonal changes that occur during puberty are associated with increased body odor.

helen ruth Researchers at Germany’s Friedrich-Alexander University studied how body odor changes from childhood to adolescence.

The team recruited 18 children up to the age of three and 18 adolescents between the ages of 14 and 18. They all washed themselves with unscented gel before bed and had cotton pads sewn to the sides of their clothes.

The researchers then extracted the compounds absorbed by the pads and identified them using a technique called mass spectrometry. They then used a process called gas chromatography and trained evaluators to detect the odorous chemicals. “The human nose is used as a detector,” Roos says.

Overall, the body odor-causing chemicals in the two groups were similar, but the chemicals collected from the teens contained higher levels of some carboxylic acids, and the judges described it as “cheap”, “musty” and “earthy”.

The researchers also identified two steroids unique to the teens’ samples, which smelled of “urine and musk” and “sandalwood and musk,” respectively. Chemical differences between teen body odor and toddler body odor may be why toddlers are generally considered to have more pleasant smells, the researchers write.

Ruth says further research into the scents we produce at different ages could help scientists develop more effective odor control measures.

but andreas natsch Swiss fragrance maker Givaudan notes that the study only assessed overnight body odor. “In adults, more pungent odors occur when they are under mental or physical stress,” he says.

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Source: www.newscientist.com