Tag Archives: luminous

Webb Discovers Surprising Hydrocarbon Abundance in Mysterious Core of Nearby Luminous Galaxy

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Astronomers utilizing the NASA/ESA/CSA James Webb Space Telescope have identified an extraordinary presence of small gas-phase hydrocarbons—such as benzene, triacetylene, diacetylene, acetylene, methane, and methyl radicals—within the concealed core of the ultra-bright infrared galaxy IRAS 07251-0248.

Hydrocarbons are influential in shaping the chemistry of the interstellar medium. However, definite observational constraints on their enrichment and relationship with carbonaceous particles and polycyclic aromatic hydrocarbons remain elusive. García Bernete et al. report Webb infrared observations of the Local Ultraluminous Infrared Galaxy (ULIRG) IRAS 07251-0248, revealing extragalactic detections of small gas-phase hydrocarbons. Image credit: García-Bernete et al., doi: 10.1038/s41550-025-02750-0.

The core of IRAS 07251-0248 (also known as 2MASS J07273756-0254540) is obscured by significant amounts of gas and dust.

This dense material absorbs most radiation emitted by the central supermassive black hole, complicating studies with traditional telescopes.

However, the infrared spectrum can penetrate this dust, providing unique insights about these regions and illuminating vital chemical processes in this heavily obscured core.

Dr. Ismael García Bernete and his team employed spectroscopic observations using Webb’s NIRSpec and MIRI instruments, covering wavelengths from 3 to 28 microns.

These observations reveal chemical signatures of gas-phase molecules alongside signatures from ice and dust particles.

These data empowered astronomers to characterize the abundance and temperature of various chemical species within the core of this concealed galaxy.

Remarkably, they discovered an exceptionally high abundance of small organic molecules such as benzene, methane, acetylene, diacetylene, and triacetylene—the first such detections outside our Milky Way, including the methyl radical.

Additionally, substantial amounts of solid molecular materials, including carbonaceous particles and water ice, were identified.

“We uncovered unexpected chemical complexity, showcasing abundances far exceeding current theoretical models,” stated Dr. García Bernete, an astronomer at the Astrobiology Center.

“This suggests a continuous source of carbon within these galactic nuclei, fueling this rich chemical network.”

“These molecules may serve as vital building blocks for complex organic chemistry, relevant to processes that pertain to life.”

Professor Dimitra Rigopoulou from the University of Oxford remarked, “Small organic molecules may not exist in living cells, yet they could play a pivotal role in prebiotic chemistry—a crucial step toward forming amino acids and nucleotides.”

These findings were published in a recent issue of Nature Astronomy.

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I. Garcia-Bernete et al. Abundant hydrocarbons within buried galactic nuclei with evidence of processing of carbonaceous particles and polycyclic aromatic hydrocarbons. Nat Astron, published online on February 8, 2026. doi: 10.1038/s41550-025-02750-0

Source: www.sci.news

Nocturnal Spiders Employ Captured Fireflies as Luminous Lures to Entice Prey

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Sheet Web Spider Psechrus Clavis is known to utilize the coloration and web of its own body as visual cues to effectively capture and consume insects. Interestingly, it doesn’t immediately eat the male fireflies, referred to as Daifan Lampaloid; instead, these spiders retain them on the web, allowing the fireflies to continue emitting bioluminescent signals for up to an hour. This observation has raised intriguing questions among a research team from Tunghai University, the University of New South Wales, the Sydney Institute of Technology, and the National Museum of Natural Sciences in Taiwan.

Sheet web spider with fireflies caught in the web. Image credit: Tunghai University Spider.

Researcher I-Min TSO and colleagues at Tunghai University documented Psechrus Clavis retaining fireflies on the web while these insects continued to emit bioluminescent light for up to an hour.

They noted that the spiders periodically check for the captured fireflies.

Fascinated by this peculiar behavior, the researchers designed an experiment to see if it serves as a hunting strategy.

The experiment involved placing firefly-like LEDs on the actual sheet spider web, using other webs as controls.

The results indicated that the web with LEDs attracted three times as many prey compared to the control web.

This figure increased to ten times more prey when actual fireflies were visible.

The findings affirm that the presence of captured fireflies enhances the spider’s hunting success.

Researchers also discovered that the majority of captured fireflies are male and likely mistaken for potential mates.

“Our findings underscore the previously unrecognized interaction where Firefly Signals, intended for sexual communication, also benefit spiders,” remarked Dr. TSO.

“This study provides new insights into how sit-and-wait predators can adapt to attract prey, revealing the intricate complexities of predator-prey interactions.”

“This behavior may have evolved in sheet web spiders as a way to avoid the energy costs associated with producing their own bioluminescence, similar to anglerfish.”

“Instead, spiders can leverage the allure of their prey’s glow to attract their own targets.”

Video recordings taken during the experiments show sheet web spiders employing various tactics when interacting with different prey species.

The spider swiftly consumes a moth caught in the web but takes its time with the trapped fireflies.

“The varying treatment of prey suggests that spiders may use specific cues to differentiate between prey species and adjust their responses accordingly,” explained Dr. TSO.

“We hypothesize that the bioluminescent signals of fireflies help spiders to fine-tune their handling behavior towards different types of prey.”

This study was published in Journal of Animal Ecology.

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Ho Yin Yip et al. Visual seduction through bioluminescence of prey seduces waiting predators. Journal of Animal Ecology Published online on August 27th, 2025. doi:10.1111/1365-2656.70102

Source: www.sci.news

Nanostructured filaments produce luminous waves that twist as they move

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Scientists at the University of Michigan say the twisted shape of the nanostructured filaments allows them to generate bright, twisted light.

Planck's law ignores, but does not prohibit, circular polarization of blackbody radiation (BBR). BBRs consisting of nanostructured filaments with twisted shapes made of nanocarbon or metal have strong ellipticity between 500 and 3000 nanometers. The submicrometer-scale chirality of these filaments meets the dimensional requirements imposed by the fluctuation dissipation theorem, which requires symmetry breaking between absorption and emissivity according to Kirchhoff's law. The resulting BBRs exhibit emission anisotropy and brightness that are 10–100 times superior to conventional chiral photon emitters. Image credit: Lu others., doi: 10.1126/science.adq4068.

“When producing twisted light using traditional methods such as electroluminescence or photon emission, it is difficult to generate sufficient brightness,” said Dr. Jun Lu, a researcher at the University of Michigan.

“We gradually realized that there is actually a very old way of producing these photons, which does not rely on the excitation of photons and electrons, but is similar to the light bulb that Edison developed. .”

“Every object that has some heat, including yourself, constantly emits photons in the spectrum associated with its temperature.”

“If an object is the same temperature as its surroundings, it will also absorb the same amount of photons. Since black absorbs all photon frequencies, this is idealized as blackbody radiation.”

Although the filament of a tungsten bulb is much warmer than its surroundings, the law that defines blackbody radiation (Planck's law) provides a good approximation of the spectrum of photons that a tungsten bulb transmits.

The photons we see as a whole look like white light, but when we pass light through a prism, we see a rainbow of different photons inside.

This radiation is also why it appears bright in thermal images, but even room-temperature objects can appear dark because they are constantly emitting and receiving blackbody photons.

Usually, the shape of the object that emits radiation is not much considered. In most cases, objects can be imagined as spheres.

However, while the shape does not affect the spectrum of different photon wavelengths, it can affect another property: polarization.

Photons from a blackbody source are typically randomly polarized, and their waves can oscillate along any axis.

New research reveals that blackbody radiation can also be twisted if the emitter is twisted on the micro or nanoscale, with the length of each twist similar to the wavelength of the emitted light.

The strength of the twist of light, or its elliptical polarization, is determined by two main factors. One is how close the wavelength of the photon is to the length of each twist, and the other is the electronic properties of the material (in this case, nanocarbon or metal).

Twisted light is also called “chiral” because the clockwise and counterclockwise rotations are mirror images of each other.

The study was done to demonstrate the premise of a more applied project that the Michigan team wants to pursue: using chiral blackbody radiation to identify objects.

They envision robots and self-driving cars that can see like a mantis shrimp, distinguishing light waves in different directions of rotation and degrees of twist.

“Advancing the physics of blackbody radiation through chiral nanostructures is at the heart of this research. Such emitters are all around us,” said Professor Nicholas Kotov of the University of Michigan.

“For example, these findings could be important in helping autonomous vehicles tell the difference between a deer and a human. Deer fur curls differently than our fabric, so even though the wavelengths are similar, Helicity emits a different light.”

The main advantage of this method of producing twisted light is its brightness, which is up to 100 times brighter than other approaches, but the light contains a wide spectrum of both wavelengths and twists.

The authors have ideas on how to address this, including exploring the possibility of building lasers that rely on twisted light-emitting structures.

They want to further explore the infrared spectrum. The peak wavelength of blackbody radiation at room temperature is approximately 10,000 nanometers or 0.01 millimeter.

“This is a noisy spectral region, but elliptical polarization could potentially enhance the contrast,” Professor Kotov says.

of the team work Published in a magazine science.

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Jun Lu others. 2024. Bright circularly polarized blackbody radiation from twisted nanocarbon filaments. science 386 (6728): 1400-1404;doi: 10.1126/science.adq406

Source: www.sci.news

IXPE uncovers a new extremely luminous X-ray source in our galaxy

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Cygnus X-3It is an X-ray binary system located about 7,400 parsecs (24,136 light years) away in the constellation Cygnus, and analysis of the data indicates that it is a type of extremely luminous X-ray source. NASA’s Imaging X-ray Polarimetry Probe (IXPE).

The halo around Cygnus X-3. Image courtesy of NASA.

“X-ray binaries are interesting systems that consist of two objects: a normal star and a compact object such as a black hole or neutron star that sucks material from the companion star,” explained astronomer Aleksandra Beredina from the University of Turku and her colleagues.

“To date, several hundred such sources have been identified in our Milky Way galaxy.”

“When it comes to the most powerful phenomena in the Universe, the release of gravitational energy in binary X-ray systems stands out as an extremely efficient process.”

“Among the first X-ray binary systems discovered in the Universe is the Cygnus X-3 system,” the researchers added.

“Since the early 1970s, this binary system has been noted for its ability to briefly appear as one of the most powerful radio sources, only to fade or disappear completely after a few days.”

“This unique feature prompted early efforts to coordinate astronomical observations around the world through telephone coordination.”

“The peculiar behaviour of this system during this short-lived, high-energy event contrasts with its normal nature and led to it being named ‘Astronomical Mystery Cygnus X-3’ by R.M. Helming in 1973.”

“Since then, there have been numerous efforts to understand its properties.”

Dr. Veredina and her co-authors used the Imaging X-ray Polarimetry Explorer to measure the X-ray polarization of Cygnus X-3.

“The X-ray polarization images provide insight into the composition of matter surrounding the compact object in Cygnus X-3,” the researchers said.

“We found that this compact object is surrounded by a dense, opaque membrane of material.”

“The light we see is a reflection from the inner walls of a funnel formed by the surrounding gas, similar to a cup with a mirror on the inside.”

“Cygnus X-3 is a type of Ultraluminous X-ray source (ULX), which consumes material at such a rate that a significant portion of the infalling material does not fall within the event horizon, but rather is ejected out of the system.”

“ULXs are usually observed as points of light in images of distant galaxies, and their radiation is amplified by the focusing effect of the funnel around the compact object, acting like a megaphone,” said Professor Juri Poutanen from the University of Turku.

“But these sources are so far away – thousands of times the extent of the Milky Way – that they appear relatively faint to X-ray telescopes.”

“This discovery reveals that luminous counterparts to these distant ULXs exist within our own Galaxy.”

“This important discovery marks a new chapter in our investigation into the source of this extraordinary universe, providing an opportunity to study its extreme matter consumption in detail.”

of result Published in the journal Natural Astronomy.

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A. Veredina othersIXPE discovered Cygnus X-3 as an ultra-luminous X-ray source in the galaxy. Nat AstronPublished online June 21, 2024, doi: 10.1038/s41550-024-02294-9

Source: www.sci.news

MUSE finds peculiar star surrounded by a luminous protoplanetary disk

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Astronomers Multi-unit spectroscopic probe The (MUSE) instrument on ESO’s Very Large Telescope (VLT) in Chile has imaged Propride, an externally illuminated protoplanetary disk around a young star, at 177-341 W. Orion Nebula.

This VLT/MUSE image shows propylid 177-341 W. Image courtesy of ESO / Aru others., doi: 10.1051/0004-6361/202349004.

Young stars are surrounded by a disk of gas and dust that gives rise to planets.

If another very bright and massive star is nearby, its light can heat up the young star’s disk and strip it of some of its material.

“Protoplanetary disks made of gas and dust emerge as a result of star formation processes and are the birth sites for planetary systems,” explained ESO astronomer Marie-Rees-Al and her colleagues.

“The evolutionary path of a protoplanetary disk and its ability to form planets depend on the surrounding environment, and we expect disks to undergo rapid changes in the presence of massive stars.”

“In massive clusters close to OB stars, ultraviolet (UV) radiation can cause the disk to photoevaporate externally, significantly reducing its size, mass, and lifetime.”

Astronomers used the MUSE instrument on ESO’s Very Large Telescope to observe 177-341W and 11 other dwarf stars in the Orion Nebula Cluster, about 400 parsecs away from the Sun.

“The stars encroaching on 177-341 W’s disk drop out of the frame after passing the upper right corner,” the researchers said.

“When that radiation collides with the material around the young star, it creates the bright bow-like structures we see in yellow.”

“The tail extending from the star toward the lower left corner is material being dragged away from 177-341 W by a star outside the field of view.”

“The colours displayed in this image represent different elements, including hydrogen, nitrogen, sulphur and oxygen,” the researchers added.

“But this is only a small part of the total data collected by MUSE. MUSE actually takes thousands of images simultaneously in different colors and wavelengths.”

a paper The findings have been published in the journal Astronomy and Astrophysics.

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M.-L. Al others2024. A kaleidoscope of irradiated disks: Propride MUSE observations of the Orion Nebula Cluster. I. Sample presentation and size of the ionization front. A&Ain press; doi: 10.1051/0004-6361/202349004

Source: www.sci.news

Largest black hole energizes the most luminous entity in the cosmos

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Artist's impression of record-breaking quasar J0529-4351

ESO/M.Kornmesser

A quasar 500 trillion times brighter than the Sun has earned the title of the brightest known object in the universe. It appears to be powered by a supermassive black hole that devours a sun-sized mass every day.

Quasars are the centers of galaxies where gas and dust falling into a supermassive black hole emit energy in the form of electromagnetic radiation. christian wolff Researchers at the Australian National University in Canberra will discover a new object called J0529-4351 in 2022 by scouring data from the Gaia Space Telescope and looking for extremely bright objects outside the Milky Way that have been mistaken for stars. The brightest quasar was discovered for the first time.

Follow-up observations from the Very Large Telescope (VLT) in Chile revealed that it is the brightest object in the universe as we know it.

Wolf and his colleagues used an instrument on the VLT called a spectrometer to analyze the light coming from J0529-4351 and calculate how much was produced by the black hole's swirling disk of gas and matter, called the accretion disk. did. This revealed that J0529-4351 is the fastest growing black hole in the universe, swallowing about 413 solar masses per year, or more than one sun per day.

Using the spectra of these lights, the researchers calculated that the mass of the black hole was between 5 billion and 50 billion solar masses.

Wolf and his colleagues also discovered the brightest quasar to date in 2018, about half as bright as J0529-4351. Wolf believes this new discovery is likely to account for most of the observable sky and remain the record holder for some time. Now, thanks to extensive star catalogs like those created by Gaia, they can be studied in great detail. “This is the largest unicorn we've ever found with the longest horn on its head. I don't think this record will ever be surpassed,” Wolf says.

The quasar's accretion disk appears to be the widest ever known, measuring 7 light-years in diameter. It says this provides a rare opportunity to directly image a black hole and precisely measure its mass. Christine Dunn At Durham University, UK. “This is large enough and bright enough that it can be solved with current equipment,” he says Done. “That means we can more directly measure the mass of this monster black hole. I was very excited about that.”

VLT is currently upgrading its spectroscopic equipment as part of the Gravity+ project, which should allow it to resolve the characteristics of J0529-4351 in detail. This means different parts of a quasar's accretion disk can be distinguished and better understood, but it could take several years, Dunn said.

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Source: www.newscientist.com