#active galactic nuclei

[netmassimo]

An image captured by the Hubble Space Telescope depicts Arp-Madore 2339-661, an object that until not many years ago was considered a pair of interacting galaxies, cataloged as NGC 7733 (bottom right) and NGC 7734 (top left). However, observing the upper arm of NGC 7733, it's possible to see a sort of large knot of a color different from the predominant blue which is actually a dwarf galaxy, now cataloged as NGC 7733N. The consequence is that the interaction taking place is what some call a merging group. Mergers between two galaxies are normal but sometimes there are more galaxies and in this case, there are three of them that show signs of having active galactic nuclei.

[spacenutspod]

The Space, Astronomy & Science Podcast. SpaceTime Series 27 Episode 26 *The Brightest and Fastest Growing Black Hole Quasar Ever Seen Astronomers have uncovered a cosmic colossus: the most luminous quasar known, powered by a black hole 17 billion times the mass of the Sun and growing at a staggering rate. The quasar J0529-4351, situated over 12 billion light-years away, is a beacon from the early universe, challenging our understanding of black hole formation and growth. *Supernova 1987A's Hidden Heart: The Neutron Star Within NASA's Webb Space Telescope has pierced through the dusty veil of Supernova 1987A, revealing emissions indicative of a neutron star's presence. This discovery resolves a long-standing debate and provides a glimpse into the violent stellar processes that forge these dense remnants. *Surviving the Cosmic Rays: Earth's First Life and the Shield of Manganese How did life's early building blocks endure Earth's intense radiation? New research suggests that cell-like structures with manganese-based antioxidants could have been life's ancient protectors, enabling the survival and evolution of the first organisms in a gamma-ray-blasted world. *Leap Year Explained: Why February Gains an Extra Day As February 29 approaches, we demystify the leap year phenomenon. Learn how this calendrical correction ensures our timekeeping stays in harmony with Earth's orbit, and discover the historical and astronomical significance behind the extra day in February. Join us on SpaceTime as we delve into the depths of black holes, witness the aftermath of stellar explosions, and explore the primordial resilience of life on our planet. Tune in for a journey through the cosmos and the intricacies of our celestial calendar. Listen to SpaceTime on your favorite podcast app with our universal listen link: https://spacetimewithstuartgary.com/listen and access show links via https://linktr.ee/biteszHQ For more SpaceTime and show links: https://linktr.ee/biteszHQ For more space and astronomy podcasts visit our HQ at https://bitesz.com Become a supporter of this podcast: https://www.spreaker.com/podcast/spacetime-with-stuart-gary--2458531/support.

[requiem-on-water]

(1) NGC 6956 barred spiral galaxy exists 214 million light-years away in the constellation Delphinus. (2) Interacting galaxies known as AM 1214-255 containing active galactic nuclei, or Agnes aka an extraordinarily luminous central region of a galaxy where its extreme brightness is caused by matter whirling into a supermassive black hole at the galaxy’s heart.

{image credit: NASA}

[importantwomensbirthdays]

Charlene Heisler

Charlene Heisler was born in 1961 in Calgary, Alberta. When Heisler was about to begin her PhD in astronomy, her doctors advised against it. They said that she would only survive a couple of years due to her cystic fibrosis. Yet she not only completed her PhD at Yale, but also became a world-renowned astronomer. Heisler made significant contributions to the understanding of active galaxies, and to why some galaxies, but not others, have broad-line regions. Her final major project was the COLA project, which sought to determine whether there was a link between active galactic nuclei and starburst activity.

Charlene Heisler died in 1999 at the age of 37. The Astronomical Society of Australia gives the Charlene Heisler Prize each year in her honor.

[bsuobservatory]

The Seyfert galaxy NGC 5985 (on the left) contains an Active Galactic Nucleus (AGN).

AGN are so. Amazing.

In the dead center of the galaxy lies a supermassive black hole—and a large amount of other matter spiraling into it, caught in the gravitational well. As matter falls in, it accelerates to relativistic speeds, ripping apart until even atoms are split into plasma, and because plasma is not electrically neutral the metaphorical whirlwind of it generates an extremely strong electromagnetic field.

That field blasts matter away from the black hole in jets. These can be truly enormous. A single jet emanating from the black hole in the monstrous elliptical galaxy M87 is roughly ten times the length of our entire Milky Way Galaxy.

Seyfert galaxies are calmer than that, but the mechanism is the same. Bright, powerful AGN tend to be found in galaxies further from our own, while Seyferts dominate the AGN population in our local universe.

At BSU, we've imaged Markarian 421, a type of AGN called a blazar, so-named because the jet is aimed almost directly toward Earth.: "blazing" bright. We're in the process of studying our data, but the eventual goal is to determine limits for the mass of the black hole powering it. The student who spearheaded that research is now pursuing a Ph.D. at Purdue University!

2023 July 1

Three Galaxies in Draco Image Credit & Copyright: David Vernet , Jean-François Bax , Serge Brunier, OCA/C2PU

Explanation: This tantalizing trio of galaxies sometimes called the Draco Group, is located in the northern constellation of (you guessed it) Draco, the Dragon. From left to right are face-on spiral NGC 5985, elliptical galaxy NGC 5982, and edge-on spiral NGC 5981, all found within this single telescopic field of view that spans a little more than the width of the full moon. While the group is far too small to be a galaxy cluster, and has not been catalogued as a compact galaxy group, the three galaxies all do lie roughly 100 million light-years from planet Earth. Not as well known as other tight groupings of galaxies, the contrast in visual appearance still makes this triplet an attractive subject for astroimagers. On close examination with spectrographs, the bright core of striking spiral NGC 5985 shows prominent emission in specific wavelengths of light, prompting astronomers to classify it as a Seyfert, a type of active galaxy. This impressively deep exposure hints at a faint dim halo along with sharp-edged shells surrounding elliptical NGC 5982, evidence of past galactic mergers. It also reveals many even more distant background galaxies.

∞ Source: apod.nasa.gov/apod/ap230701.html

[mysticstronomy]

WHAT IS MORE POWERFUL THAN A QUASAR??

Blog#409

Wednesday, June 12th, 2024.

Welcome back,

On July 12th, 2018, researchers announced that they’d caught a single, tiny, high-energy particle called a neutrino that had rained down on Earth from a supermassive black hole some 4 billion light-years away.

Astrophysicists are excited because this is only the third identified cosmic object they’ve managed to collect the elusive particles from — first the Sun, then a supernova that went off in a neighboring galaxy in 1987, and now a blazar.

So, what is a blazar, anyway?

At the center of most galaxies — including our own Milky Way — there’s a gargantuan black hole that can have the mass of millions or even billions of Suns. In some galaxies, this supermassive black hole may collect a swirling disk of gas, dust and stellar debris around it to eat from.

As material in the disk falls toward the black hole, its gravitational energy can be converted to light, making the centers of these galaxies very bright and giving them the name active galactic nuclei (AGN).

Some of these active galactic nuclei also shoot out colossal jets of material that travel close to the speed of light. Scientists call this a quasar.

But when a galaxy happens to be oriented so the jets point toward Earth — and we’re staring right down the barrel of the gun, as it were — it’s called a blazar. It’s the same thing as a quasar, just pointed at a different angle.

Those jets shoot matter at close to the speed of light in our direction and, we now know, produce high-energy neutrinos like the one detected by the IceCube instrument in September 2017.

The first blazar found was originally misidentified as an oddball of a star. In 1929, the German astronomer Cuno Hoffmeister published a catalog of 354 objects he thought were variable stars, or stars that get brighter and fainter over fairly short periods of time. This catalog included an object that was called BL Lacertae, or BL Lac for short, after the constellation it was in — Lacerta, the lizard.

By the late 1960s and 1970s, astronomers began to notice something funny about BL Lac. It did get brighter and fainter, but not in a regular, predictable way, and it seemed to emit a lot of light in the radio wave regime, which was unusual for stars.

Further studies showed that BL Lac was too far away to be a star in the Milky Way galaxy. And in some ways, its behavior looked more like another mysterious object astronomers were finding — called quasars — than it did variable stars.

Eventually, astronomers found that BL Lac was in fact a bright object in the center of a distant galaxy. And they began to find other objects that shared BL Lac’s strange properties, calling them “BL Lac objects.” By 1980, they coined the name blazars, combining “BL Lac objects” with the somewhat similar “quasars.”

Studies in the 1980s and 1990s gave evidence that the bright radio light from blazars came from jets of material moving at relativistic speeds. By the mid-1990s, astronomers determined that blazars, quasars, and some other bright galaxy phenomena they observed were all in the same family of objects: active galactic nuclei.

Originally published on www.astronomy.com

COMING UP!!

(Saturday, June 15th, 2024)

"WHY DO PLANETS ROTATE??"

[mindblowingscience]

These gas emissions are believed to fuel the process of star formation in galaxies but are not yet well understood. Astronomers are interested in learning more about them to improve our understanding of what governs galactic evolution.

This is the purpose of the SUper massive Black hole Winds in the x-rAYS (SUBWAYS) project, an international research effort dedicated to studying quasars using the ESA's XMM-Newton space telescope.

The first results of this project were shared by a group of scholars led by the University of Bologna and the National Institute for Astrophysics (INAF) in Italy. In the paper that describes their findings, the team presented X-ray spectroscopic data to characterize the properties of UFOs in 22 luminous galaxies.

Continue Reading

[thespacewirednews]

 Galaxy with ‘Forbidden’ Light

This whirling image features a bright spiral galaxy known as MCG-01-24-014, which is located about 275 million light-years from Earth. In addition to being a well-defined spiral galaxy, MCG-01-24-014 has an extremely energetic core known as an active galactic nucleus (AGN) and is categorized as a Type-2 Seyfert galaxy. Seyfert galaxies, along with quasars, host one of the most common subclasses of AGN. While the precise categorization of AGNs is nuanced, Seyfert galaxies tend to be relatively nearby and their central AGN does not outshine its host, while quasars are very distant AGNs with incredible luminosities that outshine their host galaxies.

There are further subclasses of both Seyfert galaxies and quasars. In the case of Seyfert galaxies, the predominant subcategories are Type-1 and Type-2. Astronomers distinguish them by their spectra, the pattern that results when light is split into its constituent wavelengths. The spectral lines that Type-2 Seyfert galaxies emit are associated with specific ‘forbidden’ emission lines. To understand why emitted light from a galaxy could be forbidden, it helps to understand why spectra exist in the first place. Spectra look the way they do because certain atoms and molecules absorb and emit light at very specific wavelengths. The reason for this is quantum physics: electrons (the tiny particles that orbit the nuclei of atoms and molecules) can only exist at very specific energies, and therefore electrons can only lose or gain very specific amounts of energy. These very specific amounts of energy correspond to the wavelengths of light that are absorbed or emitted.

Forbidden emission lines should not exist according to certain rules of quantum physics. But quantum physics is complex, and some of the rules used to predict it were formulated under laboratory conditions here on Earth. Under those rules, this emission is ‘forbidden’ – so improbable that it’s disregarded. But in space, in the midst of an incredibly energetic galactic core, those assumptions don’t hold anymore, and the ‘forbidden’ light gets a chance to shine out toward us. Text credit: European Space AgencyImage credit: ESA/Hubble & NASA, C. Kilpatrick

[blasteffect]

The universe as seen with the eROSITA X-ray telescope

As eROSITA scans the sky, the energy of the collected photons is measured with an accuracy ranging from 2% – 6%.

To generate this image, in which the whole sky is projected onto an ellipse (so-called Aitoff projection) with the center of the Milky Way in the middle and the body of our Galaxy running horizontally, photons have been color-coded according to their energy (red for energies 0.3-0.6 keV, green for 0.6-1 keV, blue for 1-2.3 keV).

The red diffuse glow away from the galactic plane is the emission of the hot gas in the vicinity of the Solar System (the Local Bubble). Along the plane itself, dust and gas absorb the lowest energy X-ray photons, so that only high-energy emitting sources can be seen, and their color appears blue in the image.

The hotter gas close to the Galactic center, shown in green and yellow, carries imprinted the history of the most energetic processes in the life of the Milky Way, such as supernova explosions, driving fountains of gas out of the plane, and, possibly, past outburst from the now dormant supermassive black hole in the center of the Milky Way.

Piercing through this turbulent, hot diffuse medium, are hundreds of thousands of X-ray sources, which appear mostly white in the image, and uniformly distributed over the sky. Among them, distant active galactic nuclei are visible as point sources, while clusters of galaxies reveal themselves as extended X-ray nebulosities.

In total, about one million X-ray sources have been detected in this image.

Image credit: Jeremy Sanders, Hermann Brunner & the eSASS team / Max Planck Institute for Extraterrestrial Physics / Eugene Churazov & Marat Gilfanov, IKI.

[livingforstars]

The Swirling Center of NGC 4261 - December 5th, 1995.

"What evil lurks in the hearts of galaxies? The above picture by the Hubble Space Telescope of the center of the nearby galaxy NGC 4261 tells us one dramatic tale. Here gas and dust are seen swirling near this elliptical galaxy's center into what is almost certainly a massive black hole. The disk is probably what remains of a smaller galaxy that fell in hundreds of millions of years ago. Collisions like this may be a common way of creating such active galactic nuclei as quasars. Strangely, the center of this fiery whirlpool is offset from the exact center of the galaxy - for a reason that remains an astronomical mystery."

[netmassimo]

An article being published in "The Astrophysical Journal" reports the results of the study of two galaxy mergers between dwarf galaxies with active galactic nuclei. A team of researchers used data collected by NASA's Chandra X-ray Observatory to discover candidates and then compared them with infrared observations conducted with NASA's WISE Space Telescope and optical frequency observations conducted with the Canada-France-Hawaii Telescope (CFHT).

[starryeyesmasc]

wanna go back to the Stone Age and tell someone about active galactic nuclei and watch their head explode

[spacetimewithstuartgary]

Unlocking the secrets of the first quasars: how they defy the laws of physics to grow

In the article published today in the Astronomy & Astrophysics journal, new evidence suggests how supermassive black holes, with masses of several billion times that of our Sun, formed so rapidly in less than a billion years after the Big Bang. The study, led by researchers of the National Institute for Astrophysics (INAF), analyses a sample of 21 quasars, among the most distant ever discovered, observed in the X-rays band by the XMM-Newton and Chandra space telescopes. The results suggest that the supermassive black holes at the centre of these titanic quasars, the first formed during the cosmic dawn, may have reached their extraordinary masses through very rapid and intense accretion, thus providing a plausible explanation for their existence in the early stages of the Universe.

Quasars are active galaxies powered by the central supermassive black holes (known as active galactic nuclei), which emit an enormous amount of energy as they attract matter. They are extremely luminous and distant from us. In particular, the quasars examined in this study are among the most distant objects ever observed, dating back to a time when the Universe was less than a billion years old.

In this work, the analysis of X-ray emissions from these objects revealed an entirely unexpected behaviour of the supermassive black holes at their centres: a connection emerged between the shape of the X-ray emission and the speed of the winds of matter ejected by the quasars. This relationship links the wind speed, which can reach thousands of kilometres per second, to the temperature of the gas in the corona, the region that emits X-rays closest to the black hole. Thus, the corona turned out to be connected to the powerful accretion mechanisms of the black hole itself. Quasars with low-energy X-ray emission, and thus a lower temperature in the corona, show faster winds. This indicates a highly rapid growth phase that exceeds a physical limit for the accretion of matter called the Eddington limit, which is why this phase is called "super-Eddington." Conversely, quasars with higher-energy X-ray emissions tend to exhibit slower winds.

"Our work suggests that the supermassive black holes at the centre of the first quasars formed within the first billion years of the Universe's life may have actually increased their mass very rapidly, challenging the limits of physics," says Alessia Tortosa, lead author of the study and researcher at INAF in Rome. "The discovery of this connection between X-ray emission and winds is crucial for understanding how such large black holes could have formed in such a short time, thus providing a concrete clue to solve one of the greatest mysteries of modern astrophysics."

The result was achieved mainly by analysing data collected with the XMM-Newton space telescope of the European Space Agency (ESA), which allowed for approximately 700 hours of observations of the quasars. Most of the data, collected between 2021 and 2023 as part of the Multi-Year XMM-Newton Heritage Programme, under the direction of Luca Zappacosta, a researcher at INAF in Rome, is part of the HYPERION project, which aims at studying hyperluminous quasars during the cosmic dawn of the Universe. The extensive observation campaign was led by a team of Italian scientists and received crucial support from INAF, which funded the program, thereby supporting cutting-edge research on the evolutionary dynamics of the early structures of the Universe.

"In the HYPERION program, we focused on two key factors: on one hand, the careful selection of quasars to observe, choosing the titans, meaning those that had accumulated as much mass as possible, and on the other hand, the in-depth study of their properties in X-rays, something never attempted before on such a large number of objects from the cosmic dawn," says Luca Zappacosta, a researcher at INAF in Rome. We hit the jackpot! The results we're getting are genuinely unexpected, and they all point to a super-Eddington growth mechanism of the black holes."

This study provides important insights for future X-ray missions, such as ATHENA (ESA), AXIS, and Lynx (NASA), which are scheduled for launch between 2030 and 2040. In fact, the results obtained will be useful for refining the next-generation observational instruments and for defining better strategies for investigating black holes and active galactic nuclei in X-rays at more distant cosmic epochs. These are key elements for understanding the formation of the first galactic structures in the primordial Universe.

IMAGE: AI-generated representation of an accreting supermassive black hole, surrounded by gas spiralling toward it along the equatorial plane (the accretion disk) and emitting powerful winds of matter as it falls in. This representation is based on a NASA's artist's concept that illustrates a supermassive black hole with millions to billions times the mass of our sun. Credits: Emanuela Tortosa

[spacenutspod]

2 min read Hubble Glimpses a Bright Galaxy Group This new NASA Hubble Space Telescope image shows a tangled group of interacting galaxies called LEDA 60847. NASA/ESA/A. Barth (University of California – Irvine)/M. Koss (Eureka Scientific Inc.)/A. Robinson (Rochester Institute of Technology)/Processing: Gladys Kober (NASA/Catholic University of America) This new NASA Hubble Space Telescope image shows a group of interacting galaxies known as LEDA 60847. LEDA 60847 is classified as an active galactic nuclei, or AGN. An AGN has a supermassive black hole in the galaxy’s central region that is accreting material. The AGN emits radiation across the entire electromagnetic spectrum and shines extremely brightly. By studying powerful AGNs that are relatively nearby, astronomers can better understand how supermassive black holes grow and affect galaxies. Galaxy mergers are relatively common occurrences. Most larger galaxies are the result of smaller galaxies merging. The Milky Way itself contains traces of other galaxies, indicating it is the product of past mergers. Astronomers believe somewhere between 5% and 25% of all galaxies are currently merging.  This image of LEDA 60847 combines ultraviolet, visible, and near-infrared data from Hubble. The ability to see across all those wavelengths is one of the things that makes Hubble unique. Different types of light across the electromagnetic spectrum tell astronomers different things about our universe. Ultraviolet light traces the glow of stellar nurseries and is used to identify the hottest stars. Visible light shows us moderate-temperature stars and material, and also how the view would appear to our own eyes. Last but not least, near-infrared light can penetrate cold dust, allowing us to study warm gas and dust, and relatively cool stars. LEARN MORE: Hubble’s Cosmic Collisions Hubble Science: Galaxy Details and Mergers Hubble Science: Tracing the Growth of Galaxies Download this image Media Contact: Claire AndreoliNASA’s Goddard Space Flight Center, Greenbelt, MDclaire.andreoli@nasa.gov Share Details Last Updated Jan 23, 2024 Editor Andrea Gianopoulos Location Goddard Space Flight Center Related Terms Active Galaxies Astrophysics Division Galaxies Goddard Space Flight Center Hubble Space Telescope Missions The Universe Keep Exploring Discover More Topics From NASA Hubble Space Telescope Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe. Galaxies Stories Stars Stories James Webb Space Telescope Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…

[superusrblog]

@superusrblog 👈🏻 follow

Quasars are extremely luminous active galactic nuclei powered by supermassive black holes. They are among the most distant objects observed in the universe and can outshine entire galaxies.

[kny111]

Are Some Black Holes Wormholes In Disguise? Gamma-Ray Blasts May Shed Clues

I’ve recently in my spare time been doing some reading and reviewing on supermassive black holes, relativistic jets and wormholes especially after noticing that the supermassive black hole in the movie ‘Interstellar’ didn’t have an astrophysical jet which is required for a black hole to be supermassive. This had me thinking, where else were there any inconsistencies with our main views of black holes and quasars? What are the differences between them and what makes them a quasar?

Are there some that connect with each other at different dimensionalities beyond that of our own cosmos like what occurs with hyper-black holes or are their physics perfectly accountable for within current cosmology’s explanations without hyperdimensionality explanations?

The difficulty in even figuring this out in acquiring any data and what that data looks like is it’s so difficult to spot a black hole let a alone a wormhole. In this article from Space, writers try to figure out if any such connection occurs by observing the outbursts from Active Galactic Nuclei (AGN) which are a type of supermassive black hole heavier than those at our own galactic center. These are helpful for this type of study because the temperatures the gamma ray bursts they release can be quantified and better understood. Here’s more from the article:

Unusual flashes of gamma rays could reveal that what appear to be giant black holes are actually huge wormholes, a new study finds.

Wormholes are tunnels in space-time that can theoretically allow travel anywhere in space and time, or even into another universe. Einstein's theory of general relativity suggests wormholes are possible, although whether they really exist is another matter.

In many ways, wormholes resemble black holes. Both kinds of objects are extremely dense and possess extraordinarily strong gravitational pulls for bodies their size. The main difference is that no object can theoretically come back out after crossing a black hole's event horizon — the threshold where the speed needed to escape the black hole's gravitational pull exceeds the speed of light — whereas any body entering a wormhole could theoretically reverse course.

Assuming wormholes might exist, researchers investigated ways that one might distinguish a wormhole from a black hole. They focused on supermassive black holes with masses millions to billions of times that of the sun, which are thought to dwell at the hearts of most, if not all, galaxies. For example, at the center of our Milky Way galaxy lies Sagittarius A*, a monster black hole that is about 4.5 million solar masses in size.

Anything entering one mouth of a wormhole would exit out its other mouth. The scientists reasoned that meant that matter entering one mouth of a wormhole could potentially slam into matter entering the other mouth of the wormhole at the same time, a kind of event that would never happen with a black hole.

Any matter falling into a mouth of a supermassive wormhole would likely travel at extraordinarily high speeds due to its powerful gravitational fields. The scientists modeled the consequences of matter flowing through both mouths of a wormhole to where these mouths meet, the wormhole's "throat." The result of such collisions are spheres of plasma expanding out both mouths of the wormhole at nearly the speed of light, the researchers said.

"What surprises me most of all is that no one has proposed this idea before, because it is rather simple," study lead author Mikhail Piotrovich, an astrophysicist at the Central Astronomical Observatory in Saint Petersburg, Russia, told Space.com.

The researchers compared the outbursts from such wormholes with those from a kind of supermassive black hole known as an active galactic nucleus (AGN), which can spew out more radiation than our entire galaxy does as they devour matter around them, and do so from a patch of space no larger than our solar system. AGNs are typically surrounded by rings of plasma known as accretion disks and can emit powerful jets of radiation from their poles.

Full Article: Are Some Black Holes Wormholes In Disguise? Gamma-Ray Blasts May Shed Clues