Tag Archives: clusters

Astronomers Unveil Merging Mystery: Champagne Galaxy Cluster is Two Colliding Clusters

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Astronomers unveiled a remarkable giant galaxy cluster known as RM J130558.9+263048.4 on December 31, 2020. Due to its bubble-like appearance and superheated gas, they aptly named it the Champagne Cluster. The stunning new composite image of this galaxy cluster features X-ray data from NASA’s Chandra X-ray Observatory combined with optical information from the Legacy Survey.

The Champagne Cluster appears as a luminous array of galaxies amidst a vibrant neon purple cloud. The cluster reveals over 100 galaxies split into two groups, with notable variations among them. Foreground stars display diffraction spikes surrounded by a subtle haze. Many small galaxies showcase blue, orange, or red tones and exhibit varied shapes. This indicates a multifaceted nature, while the central purple gas cloud emitted by Chandra signals a high-temperature region, indicative of two colliding clusters. Image credit: NASA / CXC / UCDavis / Bouhrik others. / Legacy Survey / DECaLS / BASS / MzLS / SAO / P. Edmonds / L. Frattare.

Recent research led by astronomer Faik Bourik from the University of California, Davis, utilized instruments from NASA’s Chandra X-ray Observatory and ESA’s XMM Newton Observatory to investigate the Champagne Cluster.

The team also analyzed data from the DEIMOS multi-object spectrometer located at the W. M. Keck Observatory.

“Our new composite image indicates that the Champagne Galaxy Cluster consists of two galaxy clusters merging to form a larger cluster,” the astronomers stated.

“In typical observations, multimillion-degree gas is roughly circular, but in the Champagne Cluster, it spans from top to bottom, highlighting the collision of two clusters.”

“Distinct clusters of individual galaxies are prominently visible above and below the center,” they added.

“Remarkably, the mass of this hot gas exceeds that of all 100 or more individual galaxies within the newly formed cluster.”

“This cluster is also abundant in invisible dark matter, a mysterious substance that pervades the universe.”

The Champagne Cluster is part of a rare category of merging galaxy clusters, akin to the well-known Bullet Cluster, where the hot gas from each cluster collides, slows, and creates a clear separation from the heaviest galaxies.

By comparing this data with computer simulations, researchers propose two potential histories for the Champagne Cluster.

One theory suggests that the two star clusters collided over 2 billion years ago, followed by an outward movement due to gravity, leading them to a subsequent collision.

Alternatively, another link posits a single collision about 400 million years ago, after which the clusters have begun moving apart.

“Further studies on the Champagne Cluster could illuminate how dark matter reacts during high-velocity collisions,” the scientists concluded.

For more insights, refer to their published paper in July 2025, featured in the Astrophysical Journal.

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Faik Bourik others. 2025. New dissociated galaxy cluster merger: discovery and multiwavelength analysis of the Champagne Cluster. APJ 988, 166;doi: 10.3847/1538-4357/ade67c

Source: www.sci.news

Astronomers Simulate Formation of Early Star Clusters – Sciworthy

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The universe has undergone significant changes. Examining the contrasts between the universe as we perceive it today and its origin nearly 14 billion years ago is a crucial area of study for astrophysicists and cosmologists. Their focus is primarily on the first billion years following the Big Bang, when the first stars and galaxies began to emerge, marking the dawn of the universe. This was the initial phase when celestial objects began to emit light on their own rather than merely reflecting the remnants of the Big Bang, and it was also the first occurrence when elements heavier than helium started forming via nuclear fusion in stars.

In a recent study, a group of scientists utilized computer simulations to explore what star clusters looked like during the dawn of the universe. Their objective was to create models of star and galaxy formation that could be confirmed by new observations made by the JWST. This approach will enhance astronomers’ understanding of galaxy formation in the early universe, particularly the influence of galaxies on dark matter, which remains enigmatic, during the birth of the first stars from cosmic dust.

The research employed a cosmological simulation code called Arepo to recreate the dawn of the universe within a three-dimensional box measuring 1.9 megaparsecs on each side. This size converts to 60 quintillion kilometers or 40 quintillion miles. Within this box, the simulation contained 450 million particles representing early elemental matter, including hydrogen, helium, various isotopes, ions, and molecules that formed together. Additionally, it incorporated particles simulating known dark matter, which is affected by gravity but does not interact with other forces. When these aggregates of particles coalesced and surpassed a specific mass threshold known as jeans mass, the code indicated the formation of a star.

The team aimed to identify where the simulated stars and particles formed structures like star clusters, galaxies, and galaxy clusters. They implemented a method to group particles that were sufficiently adjacent to be considered connected, utilizing a friend of friends algorithm. By executing multiple iterations of this algorithm in the simulated universe—some focused on dark matter and others on ordinary matter such as stars, dust, and gas—the researchers sought to ascertain the arrangement of matter in the early universe.

The resulting simulated clusters were found to have dimensions comparable to actual clusters observed by astronomers in the early universe. However, no real clusters with metal-rich stars matching those in the simulations have yet been identified. Furthermore, the number of stars present in the simulated cluster was consistent with previous observations of distant star clusters recorded by the JWST. Many simulated star clusters were unstable, indicating they were not fully bound by their internal gravity. The team also found that as stable star clusters began merging into larger structures, such as galaxies, they became unstable once more.

An unexpected finding emerged from the study. The friend-of-a-friend algorithm produced varying results when assessing dark matter versus ordinary matter. The discrepancy reached up to 50%, implying that an algorithm targeting dark matter might detect only half the objects identified by an algorithm focused on regular matter. This variance depended on the mass of the identified star clusters or galaxies, particularly evident for objects within a moderate size range of 10,000 to 100,000 solar masses and very low masses around 1,000 solar masses.

The researchers could not ascertain the reasons behind this phenomenon, suggesting their simulations might be overly simplistic for accurately representing all conditions present during the universe’s dawn. Notably, they mentioned the absence of newly formed stars ejecting materials into space in their simulations. Consequently, they proposed treating their discovery as an upper limit on the frequency of star-like and, by extension, star-containing objects forming in the early universe. Their results might illustrate instances in nature where star formation occurs extremely efficiently, yet sorting out the roles of all involved processes remains necessary.

The conclusion drawn was that cosmic dawn clusters could have coalesced to create the foundations of modern galaxies or possibly evolved into the luminous cores of later galaxies. Additionally, the simulated clusters appeared to be strong candidates for forming medium-sized black holes, the remnants of which may be detectable with deep-space telescopes.


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Hubble Discovers Cloudy Star Clusters in the Large Magellanic Cloud

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A stunning new image captured by the NASA/ESA Hubble Space Telescope reveals a star cluster known as N11, located within the expansive Magellanic Cloud.

This Hubble image depicts star cluster N11. Image credits: NASA/ESA/Hubble/C. Murray/J. Maíz Apellániz.

“This scene is part of the large Magellanic Cloud, a dwarf galaxy situated approximately 160,000 light years from the constellations Dorado and Mensa,” the Hubble astronomer stated.

“With a mass equivalent to 10-20% of that of the Milky Way, the large Magellanic Cloud is the most substantial of the numerous small galaxies orbiting our galaxy.”

“These large Magellanic Clouds host various significant stellar nursery regions where gas clouds, like those portrayed in this image, converge to form new stars.”

This latest Hubble image illustrates a segment of N11, the second-largest star-forming region within the large Magellanic Cloud.

“The Tarantula Nebula, which ranks as the largest and most active star-forming region in the large Magellanic Clouds, is a frequent target for Hubble,” the astronomer noted.

“We observe bright young stars illuminating gas clouds and sculpting masses of dust using their powerful ultraviolet rays.”

“This image represents observations spaced about 20 years apart, highlighting Hubble’s enduring legacy,” they added.

“The initial observations took place between 2002 and 2003 and provided exceptional sensitivity and resolution with the new technology at the time, the Advanced Camera for Surveys.

“We directed Hubble towards the N11 Star Cluster and accomplished something unprecedented: cataloging all the stars in our young cluster, from those with 10% to 100 times the mass of the Sun.”

“The subsequent observations utilized Hubble’s latest instruments, specifically the Wide Field Camera 3.

“These new images emphasized the cluster-filled dusty clouds, offering a fresh perspective on cosmic dust.”

Source: www.sci.news

How Galactic Clusters Influence Star Formation – Sciworthy

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A multitude of objects inhabit space, from tiny dust grains to enormous black holes. However, the focus of astronomers is primarily on these objects’ formations, held together by gravity. At the smaller scale are planets and their moons; planetary system. Then there are stars and their respective planets, forming a planetary system. Beyond that, we encounter stars, black holes, along with gas and dust in between, referred to as a galaxy. On a grander scale, the assembly of very large objects that creates larger patterns throughout the universe is termed structure. An example of such a structure is a galaxy cluster, composed of hundreds to thousands of galaxies.

Astronomers are keen to understand the influence that being part of a larger structure, such as a galaxy cluster, has on its individual objects, especially as these structures evolve over time. One research team investigated what transpires when a galaxy encounters the Abel 496 cluster, which harbors a mass approximately 400 trillion times that of the Sun and is relatively nearby, at about 140 megaparsecs or approximately 455 million light-years away from Earth.

Their goal was to study how the galaxy evolved after joining the cluster. They observed 22 galaxies within Abel 496 to identify any differences in star formation rates post-infall. Specifically, they aimed to pinpoint the last billion years, focusing on when the cluster’s regular star-forming galaxies ceased creating new stars.

The research team merged two distinct types of data regarding light emissions from the observed galaxies. The first is the long-wavelength emissions from neutral hydrogen atoms present in the interstellar dust; H I, pronounced “H One”. Analyzing these emissions helps determine how much the galaxy is being influenced by its neighboring galaxies and how much gas remains for star formation. These H I emissions were observed using the National Radio Astronomy Observatory’s Very Large Array.

The second dataset comprised short-wavelength emissions from recently formed stars, which have a mass between two to five times that of the Sun. These stars are short-lived, averaging a lifespan of less than 1 billion years. Researchers utilized luminosity patterns from these ultraviolet measurements to calculate the star formation frequency within the galaxies. These observations were conducted using the Ultra Violet Imaging Telescope aboard the AstroSat Satellite.

By combining this data, the team could delineate the history of each galaxy, assessing how long star-forming gas reserves persist and when star formation starts being influenced by the presence of other galaxies. The spatial positioning of each galaxy within the cluster was also examined to understand how the process of falling into the cluster altered their evolutionary trajectories.

The researchers found that galaxies located at the cluster’s edge experience star formation rates perceived as undisturbed, consistent with the Main Sequence. Additionally, it was noted that over half of the 22 galaxies under study reside at the center of the cluster, closely bound by gravitational forces and subject to secondary effects. Nevertheless, none of these central galaxies have fallen into the cluster for the past hundreds of millions of years, implying that they have not yet reached the region closest to the actual center of the cluster.

The team developed a five-stage evolutionary model for galaxies falling into clusters. Initially, galaxies begin their descent into clusters and continue their standard main sequence star formation, termed pre-trigger. In the second stage, other galaxies within the cluster disrupt the neutral hydrogen of the falling galaxies, triggering increased star formation.

The third stage sees a significant disturbance of the galaxy’s neutral hydrogen, escalating star formation to peak levels, designated as star formation peak. Next, during the fourth stage, the emissions of newly formed stars decline, though the galaxies are still quite disturbed, referred to as star-forming fading. The researchers estimate that these first four stages could span hundreds of millions of years. In the fifth stage, the depletion of neutral hydrogen leads star formation rates to fall below the pre-trigger main sequence, termed extinction.

In conclusion, the researchers asserted that their methodology successfully reconstructed the evolutionary history of galaxy clusters. However, they encouraged future teams to develop accurate measurement methods for both star formation and neutral gas within distant galaxies. They recommended utilizing larger samples of galaxies within clusters for more robust statistical analyses and investigating multiple clusters across various local environments to gain deeper insights into how galaxies evolve within vast structures.


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Hubble Space Telescope Reveals Breathtaking Images of Ancient Spherical Clusters

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Recent images from the NASA/ESA Hubble Space Telescope highlight NGC 1786, a spherical cluster located in the constellation of Dorado.

This Hubble image depicts NGC 1786, a spherical cluster approximately 163,000 light-years away in the Dorado constellation. The color images were created from various exposures captured in visible and near-infrared regions of the spectrum using Hubble’s Wide Field Camera 3 (WFC3). Three filters sampled different wavelengths. Colors were assigned by applying distinct hues to each monochromatic image related to individual filters. Image credits: NASA/ESA/Hubble/M. Monelli/M Hözsaraç.

Spherical clusters are ancient star systems, bound together by gravity, typically spanning around 100-200 light-years.

These clusters host hundreds of thousands, or even millions, of stars. The significant masses at the cluster’s core attract stars inward, forming a spherical configuration.

Considered among the universe’s oldest known objects, spherical clusters are remnants from the early Galactic era. It’s believed that all galaxies harbor a population of these structures.

The Large Magellanic Cloud, a neighboring dwarf galaxy located about 163,000 light-years away, possesses roughly 60 spherical clusters, including NGC 1786.

This spherical cluster, also referred to as ESO 56-39, was discovered on December 20, 1835, by the British astronomer John Herschel.

“Data from the new image is derived from spherical clusters within Milky Way galaxies, including the Large and Small Magellanic Clouds, as well as Fornax dwarf spheroidal galaxies,” stated Hubble astronomers.

“Our galaxy contains over 150 of these extensively studied ancient spherical formations.

“Due to its stability and longevity, it acts as a galactic time capsule, preserving stars from the galaxy’s formative stages.”

“While it was once believed that all stars in spherical clusters formed nearly simultaneously, our research on ancient clusters within our galaxy has revealed multiple populations of stars of varying ages,” they further explained.

“To utilize spherical clusters as historical markers, it’s essential to comprehend their formation and the origins of stars from different ages.”

“This observational program analyzed older spherical clusters like NGC 1786 in external galaxies to determine whether they contained multiple star populations.”

“Such studies can provide insights into the original formation mechanisms of the Large Magellanic Cloud as well as the Milky Way galaxy.”

Source: www.sci.news

20 Million Clouds of Energy Particles Found Surrounding Distant Galaxy Clusters

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Astronomers have identified the largest known cloud of energy particles encircling galaxy clusters, with around 20 million annual clouds around the galaxy cluster PLCK G287.0+32.9.

This new composite image, created using X-rays from NASA’s Chandra X-Ray Observatory (blue and purple), radio data from Meerkat Radio Telescope (orange and yellow), and optical images from Panstarrs (red, green, and blue), illustrates the giant galaxy cluster PLCK G287.0+32.9. Image credit: NASA/CXC/CFA/Rajpurohit et al. / panstarrs / sarao / meerkat / sao / n. wolk.

Located 5 billion light years from Earth in the Hydra constellation, PLCK G287.0+32.9 has garnered astronomers’ attention since its initial detection in 2011.

Prior research uncovered two bright relics, revealing a massive shock wave illuminating the cluster’s edges. However, the extensive, faint radio emissions filling the space between them went unnoticed.

Recent radio images have shown that the entire cluster is enveloped in a faint radio glow that is nearly 20 times the diameter of the Milky Way, suggesting an extraordinary and powerful phenomenon at play.

“We anticipated finding a bright pair of relics at the cluster’s edge. Found “The Harvard & Smithsonian Astrophysics Center” mentioned: “The Harvard & Smithsonian’s Astrophysics Center is a great way to help you get started,” Dr. Kamursh Rajprohit, an astronomer at the Harvard & Smithsonian Center for Astrophysics, noted.

“No energy particle clouds of this magnitude have been spotted in such galaxy clusters or anything comparable.”

Previous record holders, located around Abel 2255 in the Galaxy Cluster, spanned about 16.3 million light years.

In the central region of the cluster, Dr. Rajprohit and his team identified radio halos where frequencies of this scale are typically undetectable, marking the first discovery of size at 114 million light years at 2.4 GHz.

The findings posed questions for the team, providing compelling evidence of magnetic fields where cosmic ray electrons and magnetic fields extend throughout the cluster.

However, it remains uncertain how these electrons can accelerate over such vast distances.

“Very extended radio halos are seldom visible across most frequencies, as the electrons responsible for them tend to lose energy. They are aged and have cooled over time,” Dr. Rajpurohit stated.

“The discovery of this colossal halo has now led to a significant increase in radio emissions between the catastrophic impact and the rest of the cluster.”

“This suggests something is actively accelerating or re-accelerating the electrons, yet none of the usual explanations apply.”

“We suspect that extensive shock waves and turbulence may be contributing factors, but additional theoretical models are needed to arrive at a definitive conclusion.”

This discovery offers researchers a new pathway to investigate cosmic magnetic fields—one of the primary unanswered questions in astrophysics—helping to elucidate how magnetic fields shape the universe on the largest scales.

“We’re beginning to perceive space in ways we have never imagined,” Dr. Rajprohit emphasized.

“This necessitates a reevaluation of how energy and matter traverse through its grandest structures.”

“Observations from NASA’s Chandra X-ray Observatory, managed by the Smithsonian Astrophysical Observatory, reveal boxy structures, comet-like tails, and several other distinct features of the cluster’s hot gas, indicating that the cluster is highly disturbed.”

“Some of these X-ray features correspond with radio-detected structures, pointing to substantial shocks and turbulence driven by merging events, facilitating electron acceleration or re-acceleration.”

“In the core of a cluster, some of these features may arise from the merger of two smaller galaxy clusters, or an explosion triggered by an exceptionally large black hole, or a combination of both.”

Source: www.sci.news

Astronomers witness the split of dark and regular matter in the clash of two galaxy clusters

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The two galaxy clusters, known as MACS J0018.5+1626, contain thousands of galaxies each and are located billions of light-years away from Earth. As the clusters hurtled towards each other, dark matter traveled faster than normal matter.

This artist's conceptual illustration shows what happened when two massive clusters of galaxies, collectively known as MACS J0018.5+1626, collided. The dark matter (blue) in the clusters moves ahead of the associated hot gas clouds, or regular matter (orange). Both dark matter and regular matter feel the pull of gravity, but only the regular matter experiences additional effects like shocks and turbulence that slow it down during the collision. Image courtesy of W. M. Keck Observatory/Adam Makarenko.

Galaxy cluster mergers are a rich source of information for testing the astrophysics and cosmology of galaxy clusters.

However, the coalescence of clusters produces complex projection signals that are difficult to physically interpret from individual observation probes.

“Imagine a series of sand-carrying dump trucks colliding, and the dark matter would fly forward like sand,” says astronomer Emily Silich of the California Institute of Technology and the Harvard-Smithsonian Center for Astrophysics.

This separation of dark matter and normal matter has been observed before, most famously in the Bullet Cluster.

In this collision, hot gas can be clearly seen lagging behind dark matter after the two galaxy clusters push through each other.

The situation that occurred in MACS J0018.5+1626 is similar, but the direction of the merger is rotated about 90 degrees relative to the direction of the Bullet Cluster.

In other words, one of the giant galaxy clusters in MACS J0018.5+1626 is flying almost straight towards Earth, while the other is moving away.

This orientation gave the researchers a unique perspective to map the speeds of both dark and normal matter for the first time, and unravel how they separate during galaxy cluster collisions.

“Bullet Cluster makes you feel like you're sitting in the stands watching a car race, taking beautiful snapshots of cars moving from left to right on a straight stretch of road,” said Jack Sayers, a professor at the California Institute of Technology.

“For us, it's like standing in front of an oncoming car on a straight stretch of road with a radar gun and measuring its speed.”

To measure the velocity of ordinary matter, or gas, in galaxy clusters, the astronomers used an observational technique known as the kinetic Sunyaev-Zel'dovich (SZ) effect.

In 2013, they made the first observational detection of the kinetic SZ effect on an individual cosmic object, a galaxy cluster named MACS J0717.

The kinetic SZ effect occurs when photons from the early universe, or the cosmic microwave background radiation (CMB), are scattered by electrons in hot gas on their way to Earth.

Photons undergo a shift called the Doppler shift due to the movement of electrons in the gas cloud along the line of sight.

By measuring the change in brightness of the CMB due to this shift, astronomers can determine the speed of the gas clouds within the cluster.

By 2019, the study authors had made these motional SZ measurements in several galaxy clusters to determine the velocity of the gas, or ordinary matter.

They also measured the speed of galaxies within the cluster, which gave them an indirect idea of ​​the speed of dark matter.

However, at this stage of the study, our understanding of the cluster orientation was limited.

All they knew was that one of them, MACS J0018.5+1626, was showing signs of something strange going on: hot gas, or regular matter, moving in the opposite direction to dark matter.

“We saw a totally strange phenomenon where the velocities were in opposite directions, which initially made us think there might be a problem with the data,” Prof Sayers said.

“Even our colleagues simulating galaxy clusters had no idea what was going on.”

Scientists then used data from NASA's Chandra X-ray Observatory to determine the temperature and location of the gas in the cluster, as well as the extent to which it is being bombarded.

“These cluster collisions are the most energetic events since the Big Bang,” Šilić said.

“Chandra will measure the extreme temperatures of the gas, which will tell us the age of the merger and how recently the galaxy cluster collision took place.”

The authors found that before the collision, the clusters were moving towards each other at about 3,000 kilometers per second, roughly 1 percent of the speed of light.

With a more complete picture of what's going on, they were able to work out why dark matter and normal matter appear to be moving in opposite directions.

They say it's hard to visualize, but the direction of the collision, combined with the fact that dark matter and normal matter separated from each other, explains the strange speed measurements.

It is hoped that more studies like this one will be conducted in the future, providing new clues about the mysterious properties of dark matter.

“This work is a starting point for more detailed studies into the nature of dark matter,” Šilić said.

“We now have a new type of direct probe that shows us how dark matter behaves differently from ordinary matter.”

of Investigation result Published in Astrophysical Journal.

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Emily M. Silich others. 2024. ICM-SHOX. I. Methodology overview and discovery of gas-dark matter velocity separation in the MACS J0018.5+1626 merger. ApJ 968, 74; doi: 10.3847/1538-4357/ad3fb5

This article is a version of a press release provided by Caltech.

Source: www.sci.news

NASA makes “Christmas tree clusters” come alive

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The Christmas Tree Cluster, NGC 2264, is a young star cluster in the Milky Way galaxy, about 2,500 light-years from Earth. Enhanced by specific color selection and rotation, this composite image depicts these stars of varying sizes as part of a cosmic Christmas tree. Credit: X-ray: NASA/CXC/SAO. Optics: TA Rector (NRAO/AUI/NSF and NOIRLab/NSF/AURA) and BA Wolpa (NOIRLab/NSF/AURA). Infrared: NASA/NSF/IPAC/CalTech/University of Massachusetts. Image processing: NASA/CXC/SAO/L.Frattare & J. Major

NGC 2264, also known as the “Christmas Tree Cluster,” milky way depicted with a new enhanced image to resemble a cosmic Christmas tree.

  • NGC 2264 is a cluster of young stars that has been colored and rotated to emphasize its nickname, the “Christmas Tree Cluster.”
  • This composite image includes X-rays from Chandra (blue and white), optical data from WIYN (green gas), and infrared data from 2MASS (white star).
  • The stars in this cluster are between 1 and 5 million years old, while the Sun is 5 billion years old.
  • Young stars are volatile and produce strong flares of X-rays and other types of light, but not in the coordinated way shown in the animation.

A cosmic Christmas tree: NGC 2264’s starscape

This new image of NGC 2264, also known as the “Christmas Tree Cluster,” shows the shape of a cosmic tree with a glow of starlight. In fact, NGC 2264 is a cluster of young stars, about 1 million to 5 million years old, located in the Milky Way about 2,500 light-years from Earth. The stars in NGC 2264 are smaller and larger than the Sun, ranging from those with masses less than a tenth of the Sun’s mass to those containing about 7 solar masses.

Festive composite image: color and rotation

This new composite image enhances the resemblance of a Christmas tree through color and rotation choices. The blue and white light (flashing in the animated version, see video below) is a young star that emits X-rays, and the X-rays are detected. NASAChandra X-ray Observatory. Optical data from his National Science Foundation-supported WIYN 0.9-meter telescope at Kitt Peak shows gas nebulae in green star clusters that correspond to the “pine needles” of trees. Finally, the infrared data from the Two Micron All Sky Survey shows foreground and background stars as white. The image has been rotated 160 degrees clockwise from astronomers’ standard north-up orientation, so the tops of the trees appear to be toward the top of the image.

This composite image shows a Christmas tree cluster. The blue and white light (blinking in the animated version of this image) is her X-ray-emitting young star detected by NASA’s Chandra X-ray Observatory. Optical data from the National Science Foundation’s WIYN 0.9-meter telescope at Kitt Peak shows gas in the nebula in green, corresponding to the “pine needles” of trees, and infrared data from the 2-micron all-sky survey shows foreground and background shows the stars. White. The image has been rotated about 160 degrees clockwise with astronomers’ standard of north at the top, so the tops of the trees appear to be near the top of the image.

Star dynamics and observation techniques

Young stars like NGC 2264 are highly volatile, causing strong flares in X-rays and other types of fluctuations seen in different wavelengths of light. However, the coordinated blinking variation shown in this animation was done artificially to emphasize the position of the star seen in the X-rays and to emphasize the resemblance of this object to a Christmas tree. . In reality, the changes in the stars are not synchronized.

The fluctuations observed by Chandra and other telescopes are caused by several different processes. Some of these are associated with activity involving magnetic fields, such as flares like those experienced by the Sun (but much more powerful), and hot spots and spots on the star’s surface that move in and out of view as the star rotates. dark areas etc. Other possibilities include changes in the thickness of the gas obscuring the star, and changes in the amount of material falling onto the star from the surrounding gas disk.

NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center manages scientific operations from Cambridge, Massachusetts and flight operations from Burlington, Massachusetts.

Source: scitechdaily.com

Comets are the most likely carriers of life’s essential building blocks to planets in clusters

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Nearby neighboring worlds can slow down the comet enough to allow the building blocks of life to survive

Shutterstock/Bradaki

It may be easiest to deliver materials for life to neighboring planets. Comets can carry many of the key building blocks of life, such as amino acids and other organic compounds, but their ability to deliver those building blocks to a particular planet depends on the configuration of their broader systems. It may depend.

There are several ideas about how the ingredients for life began on Earth, but the common idea is that a comet hit the Earth and organic molecules were deposited here. But comets tend to travel through space at extremely high speeds, and if they hit a planet at more than about 20 kilometers per second, the chances of their important compounds surviving the impact are almost zero.

Richard Anslow Researchers at the University of Cambridge ran a series of simulations to investigate how planetary systems can slow down comets and reduce their impact velocity enough to preserve these compounds. In ideal conditions, a slow impact would leave behind a type of prebiotic soup called a comet pond within the impact crater.

They discovered that there are two types of systems that can slow down a comet by 5 to 10 kilometers per second. One is a system with relatively massive stars, where everything tends to orbit slightly. For planets that are slow and have several planets spaced closely together like peas in a pod, the comet could weave between them and lose speed over time. there is.

“The best planetary systems are on relatively low-mass planets like Earth, around high-mass stars similar to the Sun but perhaps even more massive, and close enough for other rocky planets to pass through.” “It would be in a planetary system that has comets around it,” Anslow said.

He said that if astronomers eventually detect signs of life on other planets, simply examining the overall system configuration could help them understand how it got there. and that it could advance our limited understanding of how life formed. Earth.

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Source: www.newscientist.com