. Scientific Frontline: Astrophysics
Showing posts with label Astrophysics. Show all posts
Showing posts with label Astrophysics. Show all posts

Tuesday, February 3, 2026

Supermassive black holes sit in ‘eye of their own storms,’ studies find

An artist’s rendition of the immediate vicinity around the supermassive black hole known as M87*. However, the roiling, superhot gases around these black holes extend much further than seen in this visualization. Two new studies give us new insight into the regions around these black holes and how they influence their surrounding galaxies.
Illustration Credit: S. Dagnello NRAO/AUI/NSF

Scientific Frontline: "At a Glance" Summary

  • Main Discovery: A powerful, rotating magnetic wind has been identified encircling a supermassive black hole, acting as a feeding mechanism that enables the black hole’s growth rather than pushing material away.
  • Methodology: Researchers utilized the Atacama Large Millimeter/submillimeter Array (ALMA) to detect and analyze specific light wavelengths from hydrogen cyanide (HCN) molecules, using the Doppler effect to trace the motion and structure of gas hidden behind thick dust layers.
  • Key Data: The study focused on the galaxy ESO320-G030, located approximately 120 million light-years from Earth, revealing a wind structure that contradicts previous models of purely repulsive outflows.
  • Significance: This discovery solves a persistent mystery in astrophysics regarding how supermassive black holes accrete mass efficiently, demonstrating that magnetic fields can create a "storm" that funnels matter inward rather than expelling it.
  • Future Application: Astronomers intend to survey other active galaxies to determine if this magnetic wind phase is a universal stage in the lifecycle of all supermassive black holes.
  • Branch of Science: Astrophysics and Cosmology
  • Additional Detail: The observed process parallels the mechanics of star formation ("baby stars"), suggesting that similar physical laws govern growth across vastly different cosmic scales, from small suns to galactic monsters.

Monday, January 26, 2026

What Is: Cosmic Event Horizon

The Final Boundary
An illustration of the Cosmic Event Horizon. Unlike the Observable Universe, which is defined by light that has reached us, this horizon marks the limit of causal contact. Beyond this line, space expands faster than the speed of light, meaning no signal sent from Earth today could ever overtake the expansion to reach galaxies in these regions.
Image Credit: Scientific Frontline

Scientific Frontline: Extended "At a Glance" Summary

  • The Core Concept: A theoretical boundary in the universe separating events that can ever causally affect an observer from those that never will; effectively, it marks the absolute limit of future visibility.
  • Key Distinction/Mechanism: Unlike the Particle Horizon (which defines the observable past) or the Hubble Sphere (a kinematic boundary where recession velocity equals the speed of light), the Event Horizon is a strict causal limit determined by the accelerating expansion of space. Light emitted from galaxies beyond this horizon at the present moment will never reach Earth, regardless of how much time passes.
  • Origin/History: Rooted in the standard \(\Lambda\)CDM model of cosmology; current interest is driven by the "Crisis in Cosmology" regarding Dark Energy and the Cosmological Coupling hypothesis, which suggests a link between black hole growth and cosmic expansion.
  • Major Frameworks/Components:
    • \(\Lambda\)CDM Model: The standard framework involving Dark Energy and Cold Dark Matter that predicts the horizon's existence.
    • FLRW Metric: The geometry of spacetime describing an expanding universe.
    • Cosmological Coupling: A recent hypothesis positing that black holes are the source of Dark Energy.
    • Black Hole Cosmology: A theoretical model suggesting our observable universe may be the interior of a black hole within a larger parent universe.
  • Branch of Science: Cosmology, Astrophysics, Theoretical Physics.
  • Future Application: Critical for refining models of Dark Energy and testing the limits of General Relativity; ultimately essential for predicting the long-term fate of the universe (e.g., "Cosmic Solitude").
  • Why It Matters: It defines the fundamental limits of our reality and causal connection to the rest of the cosmos. Recent theories connecting this horizon to black hole physics could radically alter our understanding of the Big Bang, suggesting our universe is a "cell" within a larger multiverse rather than an isolated expanse.

NASA Reveals New Details About Dark Matter’s Influence on the Universe

Created using data from NASAs Webb telescope in 2026 (right) and from the Hubble Space Telescope in 2007 (left), these images show the presence of dark matter in the same region of sky. Webb's higher resolution is providing new insights into how this invisible component influences the distribution of ordinary matter in the universe.
Image Credit:NASA/STScl/A Pagan

Scientific Frontline: Extended "At a Glance" Summary

The Core Concept: A highly detailed map of dark matter distribution created using data from the James Webb Space Telescope (JWST), revealing the invisible "scaffolding" that structures the universe.

Key Distinction/Mechanism: Unlike previous, blurrier maps, this new visualization is twice as sharp and provides empirical confirmation that dark matter and ordinary matter are tightly interlocked. It utilizes gravitational lensing—observing how dark matter's mass warps space and bends light from distant galaxies—to trace invisible structures with unprecedented precision.

Major Frameworks/Components:

  • Gravitational Lensing: The primary method used to detect non-luminous dark matter by measuring how it distorts background light.
  • Cosmic Evolution Survey (COSMOS): The specific region of the sky (in the constellation Sextans) observed for this study.
  • Mid-Infrared Instrument (MIRI): A key JWST instrument used to measure galactic distances and penetrate cosmic dust.
  • Matter Correlation: The study confirms a direct spatial overlap between "clumps" of dark matter and clusters of ordinary (baryonic) matter.

Branch of Science: Astrophysics, Cosmology.

Future Application: These detailed maps will help refine models of cosmic evolution, specifically clarifying how early dark matter structures accelerated the formation of the first stars and galaxies, thereby enabling the creation of planetary systems.

Why It Matters: It validates the theory that dark matter acts as the gravitational anchor for the visible universe. By proving that dark matter grew alongside ordinary matter, scientists can better understand the timeline of the universe's development, including the conditions that allowed for the emergence of planets like Earth.

Saturday, January 24, 2026

UrFU Researchers Discovered “Laughing Gas” in Interstellar Ices around Protostars

Anton Vasyunin leads the research group and laboratory.
Photo Credit: UrFU press service

Scientific Frontline: Extended "At a Glance" Summary

The Core Concept: Researchers have definitively identified nitrous oxide (N₂O), commonly known as "laughing gas," within the solid ice mantles coating dust particles around young protostars.

Key Distinction/Mechanism: Unlike the gas phase of the interstellar medium—where over 300 molecules have been identified—molecules in the solid "ice" phase are notoriously difficult to detect and are only visible via infrared absorption spectra. N₂O is only the ninth molecule ever confirmed in this frozen state.

Origin/History:

  • January 2026: Findings were reported by the Ural Federal University (UrFU) and published in the journal Astronomy and Astrophysics.
  • Methodology: The discovery relied on observational data from the James Webb Space Telescope (JWST), which was interpreted using laboratory-generated spectra of ice analogues created at UrFU's ISEAge laboratory.

Major Frameworks/Components:

  • Infrared Spectroscopy: The primary method used to detect molecular signatures in solid ices, requiring background starlight to "illuminate" the absorption features.
  • Protostars: The study analyzed 50 young stars, finding N₂O in 16 of them.
  • Orion Molecular Cloud: A specific region where half of the positive detections were located, suggesting that high-intensity ultraviolet radiation aids in N₂O formation.

Branch of Science: Astrochemistry, Astrophysics.

Future Application: These findings improve models of chemical evolution in the universe, helping scientists understand how complex volatiles form and survive in the raw materials that eventually coalesce into planetary systems.

Why It Matters: This discovery indicates that nitrous oxide is relatively abundant in star-forming regions (found in nearly a third of surveyed targets), adding a critical piece to the puzzle of how prebiotic chemistry develops in the freezing vacuum of space before planets are born.

Tuesday, January 13, 2026

The path to solar weather forecasts

Three heads are better than one. Diagram to show the different satellites that made up the ad-hoc sensor network in this study. Their combined data helped paint a picture of how a CME in 2022 changed as it passed by the Earth on its way out of the solar system.
Illustration Credit: ©2025 Kinoshita et al.
(CC BY-ND 4.0)

Scientific Frontline: "At a Glance" Summary

  • Core Discovery: Researchers successfully tracked the spatiotemporal evolution of an Interplanetary Coronal Mass Ejection (ICME) by repurposing non-scientific spacecraft instruments to monitor fluctuations in cosmic rays.
  • Methodology: The study utilized a multi-point observation strategy, synchronizing data from three distinct spacecraft—the ESA Solar Orbiter, the ESA/JAXA BepiColombo, and NASA’s Near Earth Spacecraft—to create a 3D-like reconstruction of the solar eruption's movement.
  • Detection Mechanism: The team measured "Forbush decreases," which are temporary drops in background cosmic-ray intensity caused when the strong magnetic fields of a passing ICME deflect high-energy charged particles.
  • Key Innovation: A "system-monitoring" radiation monitor on BepiColombo, originally intended only for spacecraft health checks, was calibrated and transformed into a high-precision scientific sensor to detect these particle decreases.
  • Data Integration: By correlating cosmic-ray data with magnetic-field and solar-wind measurements from March 2022, the researchers linked specific changes in the particle signals to the physical structural changes of the eruption as it moved away from the sun.
  • Primary Implication: This approach establishes a framework for continuous solar weather forecasting by utilizing existing and future spacecraft as an ad-hoc sensor network, providing crucial data to protect Earth's power grids and satellite infrastructure.

Monday, January 12, 2026

Tiny Mars’ big impact on Earth’s climate

Differences in the way Earth and Mars orbit the sun.
Image Credit: NASA

Scientific Frontline: "At a Glance" Summary

  • Main Discovery: New simulations reveal that Mars exerts a definitive gravitational influence on Earth’s long-term climate patterns and ice ages, significantly shaping the orbital cycles that drive glacial periods.
  • Methodology: Researchers utilized advanced computer models to simulate solar system dynamics over millions of years, isolating Mars' specific impact by observing Earth's orbital variations (Milankovitch cycles) with the Red Planet both present and theoretically removed.
  • Specific Data: While the 430,000-year cycle driven by Venus and Jupiter remained stable in Mars-free simulations, the 100,000-year and 2.3 million-year climate cycles disappeared entirely without Mars' gravitational pull.
  • Mechanism & Dynamics: The study demonstrated that increasing the mass of Mars in simulations stabilized Earth's axial tilt (obliquity) by reducing its rate of change, while simultaneously shortening the duration of specific orbital cycles.
  • Implication for Exoplanets: These findings suggest that small, outer-orbit planets may be critical for maintaining the climatic stability of Earth-sized worlds in the habitable zones of other solar systems.

Thursday, January 8, 2026

How Many Ghost Particles All the Milky Way’s Stars Send Towards Earth

A map of the Milky Way based on data from ESA's Gaia telescope
Image Credit: ESA

Every second, a trillion of the elusive ghost particles, the neutrinos, pass straight through your body. Now, astrophysicists from the University of Copenhagen have mapped how many ghost particles all the stars in the Milky Way send towards Earth, and where in the galaxy they originate. This new map could help us track down these mysterious particles and unlock knowledge about our Galaxy that has so far been out of reach. 

They’re called ghost particles for a reason. They’re everywhere – trillions of them constantly stream through everything: our bodies, our planet, even the entire cosmos – without us noticing. These so-called neutrinos are elementary particles that are invisible, incredibly light, and interact only rarely with other matter. The weakness of their interactions makes neutrinos extremely difficult to detect. But when scientists do manage to capture them, they can offer extraordinary insights into the universe. 

Wednesday, January 7, 2026

We finally know how the most common types of planets are created

Astronomers have now witnessed four baby planets in the V1298 Tau system in the process of becoming super-Earths and sub-Neptunes.
Image Credit: Astrobiology Center, NINS  

Thanks to the discovery of thousands of exoplanets to date, we know that planets bigger than Earth but smaller than Neptune orbit most stars. Oddly, our sun lacks such a planet. That’s been a source of frustration for planetary scientists, who can’t study them in as much detail as they’d like, leaving one big question: How did these planets form? 

Now we know the answer. 

An international team of astrophysicists from UCLA and elsewhere has witnessed four baby planets in the V1298 Tau system in the process of becoming super-Earths and sub-Neptunes. The findings are published in the journal Nature. 

“I’m reminded of the famous ‘Lucy’ fossil, one of our hominid ancestors that lived 3 million years ago and was one of the ‘missing links’ between apes and humans,” said UCLA professor of physics and astronomy and second author Erik Petigura. “V1298 Tau is a critical link between the star- and planet-forming nebulae we see all over the sky, and the mature planetary systems that we have now discovered by the thousands.”

Monday, January 5, 2026

Earliest, hottest galaxy cluster gas on record could change our cosmological models

Artist’s impression of a forming galaxy cluster in the early universe: radio jets from active galaxies are embedded in a hot intracluster atmosphere (red), illustrating a large thermal reservoir of gas in the nascent cluster.
Image Credit: Lingxiao Yuan

The scorching cloud of gas threaded between clusters of galaxies is five times hotter than current models predict, highlighting gaps in our models of galaxy cluster formation.

An international team of astronomers led by Canadian researchers has found something the universe wasn’t supposed to have: a galaxy cluster blazing with hot gas just 1.4 billion years after the Big Bang, far earlier and hotter than theory predicts.  

The result, published in Nature, could upend current models of galaxy cluster formation, which predict such temperatures will occur only in more mature, stable galaxy clusters later in the universe’s life.  

“We didn’t expect to see such a hot cluster atmosphere so early in cosmic history,” said lead author Dazhi Zhou, a PhD candidate in the UBC department of physics and astronomy. “In fact, at first, I was skeptical about the signal as it was too strong to be real. But after months of verification, we’ve confirmed this gas is at least five times hotter than predicted, and even hotter and more energetic than what we find in many present-day clusters.”  

Sunday, December 14, 2025

What Is: Gravitational Microlensing

Scientific Frontline / Stock image

The universe, in its vastness, is largely composed of matter that does not shine. For centuries, the discipline of astronomy was fundamentally limited to the study of luminous objects: stars that fuse hydrogen into helium, gas clouds excited by radiation, and galaxies that act as islands of light in the cosmic dark. This reliance on electromagnetic radiation—photons—as the primary messenger of cosmic information created a significant selection bias. It rendered the "dark sector" of the Milky Way, including brown dwarfs, black holes, old white dwarfs, and free-floating planetary-mass objects, effectively invisible to standard census techniques. To map the true mass distribution of our galaxy, astronomers required a method that did not rely on the emission of light but rather on the one force that pervades all matter: gravity. 

Friday, December 5, 2025

Where the elements come from?

The chlorine and potassium needed to support planet formation and sustain life come from exploding stars.
Image Credit: JAXA

"Why are we here?" This is humanity's most fundamental and persistent question. Tracing the origins of the elements is a direct attempt to answer this at its deepest level. We know many elements are created inside stars and supernovae, which then cast them out into the universe, yet the origins of some key elements have remained a mystery. 

Chlorine and potassium, both odd-Z elements -- possessing an odd number of protons -- are essential to life and planet formation. According to current theoretical models, stars produce only about one-tenth of the amount of these elements observed in the universe, a discrepancy that has long puzzled astrophysicists. 

Historical geography helps researchers solve 2,700-year old eclipse mystery

Artist’s interpretation of an ancient total solar eclipse. This illustration is based on artistic imagination and does not represent the exact appearance of the eclipse recorded in 709 BCE.
Image Credit: Kano Okada, Nagoya University
Based on an image by Phil Hart / NASA

Humanity’s earliest datable record for a total solar eclipse allows scientists to derive accurate measurements of Earth’s ancient rotation speed and provides independent validation of solar cycle reconstruction in the 8th century BCE.

An international team of researchers has used knowledge of historical geography to reexamine the earliest datable total solar eclipse record known to the scientific community, enabling accurate measurements of Earth’s variable rotation speed from 709 BCE. The researchers calculated how the Sun would have appeared from Qufu, the ancient Chinese capital of the Lu Duchy, during the total solar eclipse. Using this information, they analyzed the ancient description of what has been considered the solar corona—the dim outer atmosphere of the Sun visible to the naked eye only during total eclipses—and found that its morphology supports recent solar cycle reconstructions for the 8th century BCE. 

Their findings, published in Astrophysical Journal Letters, provide reliable new data about Earth’s rotation speed during this period and suggest the Sun was becoming more active after a long quiet period, independently confirming what other scientists have found using radiocarbon analysis. 

A speed camera for the universe

The stars (or rather galaxies) of the show.
A montage of eight time-delay gravitational lens systems. There’s an entire galaxy at the center of each image, and the bright points in rings around them are gravitationally lensed images of quasars behind the galaxy. These images are false-color and are composites of data from different telescopes and instruments.
Image Credit: ©2025 TDCOSMO Collaboration et al.
(CC BY-ND 4.0)

There is an important and unresolved tension in cosmology regarding the rate at which the universe is expanding, and resolving this could reveal new physics. Astronomers constantly seek new ways to measure this expansion in case there may be unknown errors in data from conventional markers such as supernovae. Recently, researchers including those from the University of Tokyo measured the expansion of the universe using novel techniques and new data from the latest telescopes. Their method exploits the way light from extremely distant objects takes multiple pathways to get to us. Differences in these pathways help improve models on what happens at the largest cosmological scales, including expansion.

Friday, November 28, 2025

Stars defy the black hole: research in Cologne shows stable orbits around Sagittarius A*

Image Credit: NASA

New observations made with the ERIS instrument at the Very Large Telescope facility disprove from the assumption that the supermassive black hole at the center of the Milky Way devours nearby dust objects. 

An international research team led by PD Dr Florian Peißker at the University of Cologne has used the new observation instrument ERIS (Enhanced Resolution Imager and Spectrograph) at the Very Large Telescope (VLT) facility in Chile to show that several so-called ‘dusty objects’ follow stable orbits around the supermassive black hole Sagittarius A* at the center of our galaxy. Earlier studies had surmised that some of these objects could be swallowed up by the black hole. New data refutes this assumption. The findings have been published under the title ‘ABCD’ in the journal Astronomy & Astrophysics

The study focused on four of these unusual celestial bodies, which have been the subject of much discussion in recent years. In particular, G2 was long regarded as a pure dust and gas cloud. It was thought to have been initially elongated by the gravitational pull of Sagittarius A*, a process known as 'spaghettification', before being destroyed. However, the specific observations made with ERIS, which captures radiation in the near-infrared range, show that G2 follows a stable orbit. This is an indication that there is a star inside the dust cloud. These results confirm that the center of the Milky Way is not only destructive but can also be surprisingly stable. 

Wednesday, November 26, 2025

After nearly 100 years, scientists may have detected dark matter

Gamma-ray image of the Milky Way halo (with details).
Gamma-ray intensity map excluding components other than the halo, spanning approximately 100 degrees in the direction of the Galactic center. The horizontal gray bar in the central region corresponds to the Galactic plane area, which was excluded from the analysis to avoid strong astrophysical radiation.
 Image Credit: ©2025 Tomonori Totani, The University of Tokyo

In the early 1930s, Swiss astronomer Fritz Zwicky observed galaxies in space moving faster than their mass should allow, prompting him to infer the presence of some invisible scaffolding — dark matter — holding the galaxies together. Nearly 100 years later, NASA’s Fermi Gamma-ray Space Telescope may have provided direct evidence of dark matter, allowing the invisible matter to be “seen” for the very first time.

Dark matter has remained largely a mystery since it was proposed so many years ago. Up to this point, scientists have only been able to indirectly observe dark matter through its effects on observable matter, such as its ability to generate enough gravitational force to hold galaxies together. The reason dark matter can’t be observed directly is because the particles that make up dark matter don’t interact with electromagnetic force — meaning dark matter doesn’t absorb, reflect or emit light.

Monday, November 17, 2025

A new angle of study for unveiling black hole secrets

The balloon-borne telescope XL-Calibur was launched on a six-day flight from the Swedish Space Corporation’s Esrange Space Center in July 2024. During that flight, the telescope took measurements from the black hole Cygnus X-1, located about 7,000 light-years away. WashU researchers will use those results to improve computer models for simulating and uncovering further mysteries of black holes.
Photo Credit: NASA/SSC

An international collaboration of physicists including researchers at Washington University in St. Louis has made measurements to better understand how matter falls into black holes and how enormous amounts of energy and light are released in the process.

The scientists pointed a balloon-borne telescope called XL-Calibur at a black hole, Cygnus X-1, located about 7,000 light-years from Earth. “The observations we made will be used by scientists to test increasingly realistic, state-of-the-art computer simulations of physical processes close to the black hole,” said Henric Krawczynski, the Wilfred R. and Ann Lee Konneker Distinguished Professor in Physics and a fellow at WashU’s McDonnell Center for the Space Sciences.

A sparkling ‘Diamond Ring’ in space: Astronomers in Cologne unravel the mystery of a cosmic ring

Stars Brewing in Cygnus X
Image Credit: NASA/JPL-Caltech/Harvard-Smithsonian CfA

The structure of gas and dust resembles a glowing diamond ring. Computer simulations and observations made on board the 'flying observatory' SOFIA are now able to explain the special shape. 

An international team led by researchers from the University of Cologne has solved the mystery of an extraordinary phenomenon known as the ‘Diamond Ring’ in the star-forming region Cygnus X, a huge, ring-shaped structure made of gas and dust that resembles a glowing diamond ring. In similar structures, the formations are not flat but spherical in shape. How this special shape came about was previously unknown. The results have been published under the title ‘The Diamond Ring in Cygnus X: an advanced stage of an expanding bubble of ionized carbon’ in the journal Astronomy & Astrophysics

The ring has a diameter of around 20 light years and shines strongly infrared light. It is the relic of a former cosmic bubble that was once formed by the radiation and winds of a massive star. In contrast to other similar objects, the ‘Diamond Ring’ does not have a rapidly expanding spherical shell, but only a slowly expanding ring. 

Sunday, November 9, 2025

Astrophysics: In-Depth Description

An illustration of the vast and complex field of astrophysics, featuring elements that represent celestial objects and phenomena.
Image Credit: Scientific Frontline / stock image

Astrophysics is the branch of physics that applies physical laws and theories to understand the origin, evolution, structure, and behavior of celestial objects and phenomena. Its primary goal is to use the principles of physics to explain the universe and everything within it, from stars and planets to galaxies and the entirety of the cosmos.

Wednesday, November 5, 2025

Are there different types of black holes? New method puts Einstein to the test

At the current resolution of telescopes, black holes predicted by different theories of gravity still look very similar. Future telescopes will make the differences more visible, making it possible to distinguish Einstein's black holes from others.
(Image text translation: Einsteinian Black hole and Alternative Black hole)
Image Credit: L. Rezzolla / Goethe University

Images of black holes are more than just fascinating visuals: they could serve as a “testing ground” for alternative theories of gravity in the future. An international team led by Prof. Luciano Rezzolla has developed a new method to examine whether black holes operate according to Einstein’s theory of relativity or other, more exotic theories. To that end, the researchers conducted highly complex simulations and derived measurable criteria that can be tested with future, even sharper telescopes. Over the next few years, this method could reveal whether Einstein’s theories hold true even in the most extreme regions of the universe.

Black holes are considered cosmic gluttons, from which not even light can escape. That is also why the images of black holes at the center of the galaxy M87 and our Milky Way, published a few years ago by the Event Horizon Telescope (EHT) collaboration, broke new ground. “What you see on these images is not the black hole itself, but rather the hot matter in its immediate vicinity,” explains Prof. Luciano Rezzolla, who, along with his team at Goethe University Frankfurt, played a key role in the findings. “As long as the matter is still rotating outside the event horizon – before being inevitably pulled in – it can emit final signals of light that we can, in principle, detect.”

Monday, November 3, 2025

Dark matter does not defy gravity

Map of the distribution of galaxies observed by the DESI collaboration, from which it is possible to accurately measure the velocities of galaxies.
Image Credit: © Claire Lamman/DESI collaboration; custom colormap package by cmastro.

Does dark matter follow the same laws as ordinary matter? The mystery of this invisible and hypothetical component of our Universe — which neither emits nor reflects light — remains unsolved.  A team involving members from the University of Geneva (UNIGE) set out to determine whether, on a cosmological scale, this matter behaves like ordinary matter or whether other forces come into play. Their findings, published in Nature Communications, suggest a similar behavior, while leaving open the possibility of an as-yet-unknown interaction. This breakthrough sheds a little more light on the properties of this elusive matter, which is five times more abundant than ordinary matter.

Ordinary matter obeys four well-identified forces: gravity, electromagnetism, and the strong and weak forces at the atomic level. But what about dark matter? Invisible and elusive, it could be subject to the same laws or governed by a fifth, as yet unknown force.

Dark matter falls into gravitational wells in the same way as ordinary matter, thus obeying Euler's equations.

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