The amazing beauty of galactic collisions. A closer look at the center of NGC 3256 reveals that the chaos there is struggling to restore order. Dark dust clouds and bright stars can still maintain their general spiral distribution. credit: ESA / Hubble, NASA Every now and then, a heavenly image will fall that is so fascinating, so moving, that it stops you in your tracks.
No matter what kind of object it is, planet, nebula, star cluster, galaxy, it is their art that somehow reaches you. NGC 3256 is one of those objects. This image from the Hubble Space Telescope is one of those works of art. Pictures like this take my breath away. At first glance, this is its scope, in general, its wonderfully complete nature.
But then your eye begins to descend in detail, and you see thousands of stars as specks of light that make up the image, streams of filigree-shaped dark dust that your eye can see, and then as soon as your gaze wanders. The galaxies are taken from the background, so far away that the universe has aged considerably by the time they came into our light.
NGC 3256 is fine arts
But as lush and rewarding as this image is for its aesthetics, the science, the reality, behind it, is even more impressive. NGC 3256 are two galaxies that collide, merging into one. The galaxy is something huge, something so vast that our brains struggle to understand it. A decent-size galaxy could have a hundred billion stars, gas, and dust with the same amount of mass and a halo of invisible dark matter around it.
The Milky Way is 100,000 light-years across, which means it takes 100 millennia for light, the fastest thing in the universe, to make that journey. In human terms, from one side to the other it is 1,000,000,000,000,000,000 kilometers. An amazing distance. Galaxies exist in clusters, even strong clusters of tens to thousands of members. They are unique in this way in the universe; Most of the objects are small and far away.
trillions of kilometers away
For example, a star may be a million kilometers wide, but the closest star to it is tens of trillions of kilometers away. The size of the stars and the distance between them can be in the millions. But with galaxies, this ratio can be much lower. Not millions, not even thousands, but maybe ten. Under. Because of this, galaxies can get unnecessarily close to each other. And if they get too close, they can collide.
Even if they don’t collide directly, they can gravitationally affect each other, which is why astronomers still classify it as a collision. The gravity of one galaxy can pull on the outskirts of another, ripping out giant streamers of stars and gas, creating long, bulging tidal tails. These are common places where galaxies congregate.
But if they approach each other slowly enough and pass close enough, they won’t be able to overcome each other’s gravity. The physics is complicated, but the result is inevitable: they merge. Massive forces shake them, creating conflict and devastation, throwing stars like leaves into a dust devil. Conversely, perhaps, physical collisions of stars are extremely rare, since they are small and the distances are very large.
But nebulae, gas clouds, can be tens or even hundreds of light years across, and collisions between them are common in mergers. It could collapse the clouds, causing the birth of a fiery star. Collision galaxies are prolific, and we poetically call them starburst galaxies. NGC 3256 has it all. About 500 million years ago, two spiral galaxies came close to each other.
Maybe they missed the first pass, just to slow down, reverse course, and back away from each other. Chaos ensued, the visible remains have survived to this day. You can see a tidal tail on the left and another still experiencing turbulent times on the right. But order can be found even in chaos. Now there are patterns in the center of a single galaxy, clumps of dust still moving around the center thousands of light years away.
The spiral arms are altered but still retain some structure. The colliding gas clouds are fertile, and NGC 3256 now forms stars at a speed 75 times that of the Milky Way. Surprisingly, the two main tails have very different stars. Many of the stars on the left are undoubtedly about 300 million years old, formed after a collision. The faint tail on the right contains mostly older stars, around 800 million years.
So they were already present in one of the two mating galaxies, and were there to see the merger for the first time. Although we see this association of the two galaxies 400 million years after the primary event, it is too late to see them in flagrante delicto, but still long enough to see the effect.
What will it be like after 400 million years?
I suspect that the general spiral structure may persist, although it will be a long time before peace returns. Oh how I would love to see this galaxy for ages to come! But our descendants can still see something even more spectacular.
When you look at NGC 3256, you are looking at our future. In four billion years, the giant Andromeda galaxy, easily twice our mass, will collide with the Milky Way. The merger would eventually produce something like NGC 3256, albeit briefly in cosmic time, until it becomes something of a higher general order.
A simulation based on real physics shows what the collision of the Milky Way and the Andromeda galaxies will look like in the next billions of years. Note that this is based on previous observations, and the distance they cross first is likely greater than what is shown here. Note that the stars turn red after the collision; A giant star-forming explosion can deplete the gas available for star birth, so no more stars form after a few hundred million years.
Giant blue stars waste their fuel excessively and die quickly, leaving behind red stars to light up the universe. This collision will occur during the life of the Sun; The planets can still orbit it when a collision occurs, giving our distant children a view that is unique in our experience. You will see wonders in your sky that we can only imagine and that we can see for ourselves through galaxies like NGC 3256 from far away.
Hubble discovers that “staggering in the galaxies” Observations may insinuate the nature of dark matter. Using the NASA / ESA Hubble Space Telescope, astronomers have discovered that the brightest galaxies within the clusters of galaxies are “inlays” in relation to the center of mass of the group.
staggering in the galaxies
This unexpected result is inconsistent with the predictions made by the current standard dark matter model. An additional analysis can provide insight into the nature of dark matter, perhaps even indicating that the new physics is functioning.
More than 25 percent of all mass energy in the universe constitutes dark matter, but it cannot be seen directly, which makes it one of the greatest mysteries of modern astronomy. Invisible metamorphic dark matter surrounds galaxies and galaxy clusters alike. The latter are large-scale clusters of a thousand galaxies submerged in hot differential gas.
These clusters have very dense nuclei, each of which contains a massive galaxy called the “brightest cluster galaxy” (BCG). Hubble Seas, twelve images of the same galaxy divided by gravitational lenses: An effect called a strong gravitational lens has allowed the NASA / ESA Hubble Space Telescope to see the same distant galaxy multiple times.
Hubble uses gravitational lenses
Called PSZ1 G311.65-18.48, the galaxy is about 11 billion light-years from Earth and a massive foreground galaxy is 4.6 billion light-years away from the lens. This Hubble image shows a massive galaxy cluster, which is about 4.6 billion light-years away. 12 images appear within four arcs along their edges.
These are copies of the same galaxy called PSZ1 G311.65-18.48, which is about 11 billion light-years away. Three of these arcs appear in the upper right of the image, while a counter appears in the lower left, partially obscured by a bright star in the foreground within our Milky Way. Hubble uses gravitational lenses to study objects that would otherwise be very sensitive and even too small for its sensitive instruments.
The known Senserturst arc, PSZ1 is no exception to G311.65-18.48, one of the brightest gravitational galaxies. The lens makes multiple images of this galaxy 10-30 times brighter. This allows Hubble structures to look as small as 520 light years away, a rare detailed observation of a distant object.
analogue of galaxies
This compares quite well to the star-forming regions in galaxies in the local universe, allowing astronomers to study the galaxy and its environment in great detail. Hubble’s observations showed that PSZ1 G311.65-18.48 is an analogue of galaxies that existed long ago in the history of the universe: an era known as the era of times, an era that only 150 million after the Great Bang began to over the years.
This was an important time in the early universe, ending the dark ages, the era before the first stars were created when the universe was dark and filled with neutral hydrogen. Once the first stars formed, they began to radiate light, producing the high-energy photons necessary to ionize neutral hydrogen. It converted space matter into a primarily ionized form, in which it still exists today.
survived the first galaxies
However, to ionize interhydrogen hydrogen, the high-energy radiation from these first stars would have to escape from their host galaxies without first being absorbed by interstellar matter. So far only a very small number of galaxies. High-energy photons of the leak have been found in deep space. How this light survived the first galaxies remains a mystery.
PSZ1 G311.65-18.48 analysis helps astronomers add another piece to the puzzle. It appears that at least a few photons can exit through narrow channels in a gas-rich neutral medium in the galaxy. This is the first observation of a long theorem process. While this process is unlikely to be the primary mechanism that led to the recreation of the universe. It may very well provide a decisive boost.
astronomers has analyzed ten clusters of galaxies
The standard dark matter model (cold dark matter model) predicts that once a cluster of galaxies has returned to a “rest” state after experiencing the turbulence of a melting event, BCG does not move from the center of the cluster.
This is due to the enormous gravitational effect of Dark Matter. But now, a team of Swiss, French and British astronomers has analyzed ten clusters of galaxies seen with the NASA / ESA Hubble Space Telescope, and discovered that their BCGs are not fixed in the center.
Hubble discovers that - staggering in the galaxies
Hubble data indicates that they have been “staggered” around the center of mass of each group, when the group of galaxies has returned to a resting state after fusion. In other words. The center of the visible parts of each cluster of galaxies and the center of the total mass of the cluster, including its halo of dark matter, are displaced, up to 40,000 light years.
We discovered that BCFL, the Swiss astronomer, David Harvey and the lead author of the article, David Beevi, point out that BC indicates that, instead of a dense area in the center of the galaxy cluster As the cold dark matter model predicts , has a very shallow central density. It is an important sign of strange forms of dark matter in the heart of galaxy clusters.
The wobble of the BCG can only be analyzed since the galaxy clusters studied also act as gravitational lenses. They are so large that they give spacetime enough deformation to distort the light of the most distant objects behind them. This effect, called a strong gravitational lens, can be used to create a map of the dark matter associated with the cluster.
Which allows astronomers to locate the exact position of the center of mass and then from this center. You can measure the displacement of BCG. If this “wobble” is not an unknown astronomical event and is actually the result of Dark Matter’s behavior, then it is inconsistent with the standard Dark Matter model and can only be explained when Dark Matter particles interact with each other.
Strong contrasts with the current understanding of dark matter. This may indicate that a new fundamental physics is needed to solve the mystery of dark matter. Frederick Courbin, co-author of EPFL, also concluded. We expect larger surveys such as the Euclid Survey, which will expand our data set.
galaxy & small flakes of dark matter
Then we can determine if the wobble of the BGC is the result of a new astrophysics event or a new fundamental physics. Both will be exciting! Hubble detects little known groups of dark matter. This graphic shows how the light of a distant Kaiser is replaced by a huge foreground galaxy and small flakes of dark matter along the path of light.
The galaxy’s powerful gravity amplified and improved Kaiser’s light, creating four distorted images of the quasar. Dark matter flakes reside in and around the foreground galaxy, along with the quasar line of the Hubble Space Telescope.
The appearance of Dark Matter changes the apparent brightness and position of each quasar image distorted by tilting and tilting slightly as it travels from the distant Kasar to Earth, as indicated by the wavy lines in the graph.
Astronomers compared these measurements with an estimate of how the image would look without the effect of dark matter groups. The researchers used these measures to calculate the mass of small concentrations of dark matter.
Dark matter is the gravitational
Dark matter is an invisible substance that forms most of the mass of the universe and forms the scaffold in which galaxies are formed. Quadruple images of a quasar are rare because the background quasar and the foreground galaxy require almost complete alignment.
When looking for dark matter, astronomers must go like a “ghost hunt.” This is because dark matter is an invisible substance that cannot be observed directly. However, it forms most of the mass of the universe and forms the scaffold in which galaxies are formed. Dark matter is the gravitational “glue” that holds galaxies and galaxy clusters together.
Astronomers can detect their presence indirectly to discover how their gravity affects stars and galaxies. Mysterious matter is not made of the same things that stars, planets and people do. This material is common “barionic” material, which includes electrons, protons and neutrons.
However, dark matter may be some type of unknown subatomic particle that contacts weakly with normal matter. A popular theory holds that dark matter particles do not move very fast, which makes it easier for them to collide with each other.
Dark Matter forms
According to this view, the universe has a wide range of dark matter concentrations from small to large. Astronomers have detected groups of dark matter around large and medium galaxies. Now, using Hubble and a new observation technique, astronomers have discovered that dark matter forms much smaller groups than previously known.
The researchers discovered small concentrations of dark matter in the Hubble data. Which show how light is affected by distant quasars when they travel from space. The quasars are the luminous nuclei driven by black holes of very distant galaxies.
Hubble images show that the light from these quasar images is largely distorted and amplified by the gravity of foreground galaxies in an effect called gravitational lens. Astronomers used this lens effect to detect small scales of dark matter.
massive foreground galaxy
The tweezers are located along the telescope to the quasars, as well as around the foreground lens galaxies. Using NASA’s Hubble Space Telescope and a new observation technique. Astronomers have discovered that Dark Matter forms much smaller groups than before. This result confirms one of the fundamental predictions of the widely accepted theory of “cold dark matter.”
Each of these snapshots of the Hubble Space Telescope shows a background quasar around the middle nucleus of a broad massive galaxy and four distorted images of its host galaxy. The gravity of the massive foreground galaxy is acting like a magnifying glass by striking the light of the quasar in an effect called gravitational lens.
Caesars are extremely distant cosmic lanterns created by active black holes. Such quadruple images of quasars are rare due to the almost exact alignment between the anterior galaxy and the background quasar.