Journey to the Andromeda Galaxy [4K]

The universe is filled with galaxies much larger, brighter, and more densely populated with stars than the Milky Way, but most are so inconceivably far away that they are too faint to be seen with the naked eye; However, there is one

galaxy

that appears visible at night. sky a

galaxy

that has revealed to us as much about the universe as about itself that galaxy is the

andromeda

galaxy a vast and ancient colony of stars more than twice the size of the milky way today we will embark on a

journey

from the ancient history galaxy to its remote future using the most beautiful images and intricate data to learn about our cosmic neighbor like never before this is our

journey

to the

andromeda

galaxy the andromeda galaxy is known by many names this is due to the constellation in which it may be found with Named after the Phoenician princess Andromeda, wife of Perseus in Greek mythology, she is also known as NGC 224 and Messier 31 according to the various star catalogs in which she has appeared.

Unlike most galaxies, Andromeda is visible. with the naked eye and is best seen in dark, moonless skies during autumn and winter nights in the Northern Hemisphere. As such, it was discovered long before we knew other galaxies existed, but was incorrectly assumed to be a nebula residing within the boundaries of the Milky Way for the longest time, the first known mention of the galaxy came in 964 AD. in the persian philosopher abd al-rahman al-sufi's book of fick stars, which recorded it as a nebulous blob, but it was not studied in greater detail until the invention of the telescope in the early 17th century, when it was rediscovered.

By Simon Marius later in 1764, the object was added as entry number 31 in Charles Messier's catalog of diffuse deep-sky objects, which included a number of other galaxies unbeknownst to Messier himself, later that century, William Herschel noticed that the center of M31 appeared to have a red color. hue compared to the outside and because he was able to observe such fine details, he incorrectly assumed that Andromeda was the closest of all the large nebulae, postulating a distance of no more than 18,000 light years in 1845. William Parsons was the first to identify a spiral structure in galaxies m51 and m99 and five years later added Andromeda along with these galaxies and several others to a new classification of so-called spiral nebulae, believing that they were their own type of gaseous cloud within the Milky Way, not all The nebula's explanation convinced him: some highly respected minds of the time, starting with the 18th-century philosopher Emmanuel Kant, suggested that this object might actually be its own island universe, a vast congregation of stars like the Milky Way, but situated far beyond any other.

Another object at the time, however, was that the Milky Way was thought to encompass the entire universe and this idea placed the distance of m31 on a scale too vast for contemporary astronomers to accept. That was until 1917, when American astronomer Heber Curtis witnessed a nova event coming from within. m31, where a transient luminous object briefly eclipsed its surroundings after exploring the object's limited collection of historical photographs, Curtis found no less than 11 other nova events that occurred within Andromeda considerably more than anywhere else in the Milky Way, but they all seemed to be around 10 magnitudes. fainter than those observed in other parts of the sky, it was at that moment that Curtis realized that what he was looking at was not a nebula but a much more distant and remote colony of stars, like the Milky Way.

This led Curtis to revive Emmanuel Kant's insular universe hypothesis by proposing Andromeda. was approximately half a million light years away, but this claim was disputed by many scientists, particularly fellow American astronomer Harlow Shapley, who had previously measured the Milky Way and therefore what he considered to be The entire universe was about 300,000 light years in diameter. This culminated in one of the most significant events in 20th century science: the great debate of 1920, where Shapley and Curtis argued the nature of the universe and spiral nebulae versus A live audience at the Smithsonian Museum of Natural History Shapley in the On the one hand argued that the Milky Way was the entire universe and that all known spiral objects were simply their own type of nebula residing within it.

He argued that if they really were other galaxies, their distance would have to be on the order of tens of millions of light. years a leap scale that not many contemporary astronomers were willing to accept Curtis, on the other hand, highlighted the excessive density of novae with Andromeda compared to the rest of the Milky Way, argued that no type of nebula could explain the high number but The constant darkness of these events also pointed out dark lines within early photographs of Andromeda's spirals, noting their similarities to the opaque dust clouds found within the Milky Way's avoidance zone, but the debate ultimately failed. yielded a clear winner and it took another four years for the question to finally be resolved. being laid down in 1924 edwin hubble settled the debate by using the hooker telescope in california to measure pulsating cepheid variable stars within andromeda the pulsation period of a variable star is indicative of its luminosity and once we know the luminosity of a star we can compare it with its apparent luminosity Earth's brightness to limit a distance Using this technique, Hubble demonstrated indisputably that m31 was more than a million light years away and therefore had to be its own galaxy, in addition, all the so-called spiral nebulae that had been discovered were also their own galaxies.

Tens of millions of light years beyond our local group, the terrifying true scale of the universe had been revealed: a universe filled with thousands or perhaps even millions of galaxies, a scale far beyond anything ever thought possible. before, once we realized that m31 was a separate galaxy. Our understanding of the universe took a giant leap thanks to its proximity. Andromeda offers an unparalleled opportunity to study a spiral galaxy like the Milky Way from the outside looking in. In the 1950s we were making radio maps of the galaxy and today the NASA's four large space observatories regularly examine Andromeda for ultraviolet, infrared, and distant and telescopes like Hubble, which regularly look at galaxies billions of light years away in a vacuum, a galaxy less than 3 million light years away is a simple task and therefore we have a wide range of images Beautifully detailed and amazing Andromeda.

We have made mosaics of its stars and maps of its In its interior we have found clusters, clouds, neutron stars and black holes within its limits. Its interior contents mirror that of our own galaxy, but often on a larger scale, so without further ado, let's delve into these findings as we make our way to Andromeda. Andromeda is a barred spiral galaxy like the Milky Way that consists of a peripheral spiral structure of dust and gas connected by a dense concentration of bar-shaped stars in the galactic core. The structural similarities of our neighboring galaxy with our own galaxy suggest that the two followed similar evolutionary paths.

Andromeda is believed to have formed about 10 billion years ago and has been growing, colliding with and consuming other galaxies since m31's torrid past is evident in its enormously elongated structure. The visible component of the galaxy is believed to be about 120,000 light years old. The diameter is not very different from that of the Milky Way; However, Andromeda's entire structure includes an extended disk of scattered stars thrown outward by tidal interactions, giving the galaxy a maximum extent of about 220,000 light years, by far the largest object in the local group. ; its stellar population vastly outnumbers. Even the most generous estimates for the Milky Ways, where m31 is thought to host more than a trillion stars, the distance between the galaxy and Earth has been limited by several different methods, with most measurements agreeing on a value of approximately 2.56 million light years the first time.

One step in this enormously expansive journey occurs as we rise above the plane of the Milky Way, as less and less starlight extinguishes our view of galaxies beyond the local group. The true mind-blowing scale of this enormous universe becomes evident once we have passed beyond the peripheral stars of the Milky Way and their ghostly satellite galaxies and reached intergalactic space almost as empty as it can be in a universe dominated by gravity. By comparison, the air we breathe on Earth contains about 10 trillion trillion atoms per cubic meter, even just above the atmosphere in space there are still a million trillion atoms per cubic meter.

Interstellar space between stars only contains about a thousand atoms per cubic meter, but in intergalactic space that count drops to just 10 atoms per cubic meter, but that being said, there's nothing out there, the big galaxy. The highway also contains the most unfortunate stars and planetary systems that have been completely ejected from their galaxy by the enormous tidal forces of the collisions. Conditions on those worlds are as cold and lonely as those found in space without a heat source. of any kind out here, rogue intergalactic planets freeze from their atmospheres to their cores. Only halfway through our cosmic journey do we begin to deviate towards the territory of Andromeda, not yet towards its star fields, but towards its enormous galactic atmosphere, like the Milky Way that surrounds it.

Andromeda is a diffuse halo of plasma that is believed to have been ejected with tremendous force by the reverberations of Andromeda's past collisions. This gives the halo a truly astonishing radius of 1.3 million light years that extends more than half the distance between m31 and us. Within this atmosphere we find that of Andromeda. satellite galaxies, each of which hides clues to its violent past Andromeda is currently home to over 20 known satellite galaxies and probably had more in its past that it has since devoured. Of these satellite galaxies, there are three in particular that are believed to have played a role. key role in the formation Andromeda's elongated, skewed structure and its enormous galactic halo are more disordered 32, more disordered 110 and 33, also known as the triangulum galaxy m32 is a small elliptical dwarf galaxy seen as a small blur of golden light In close-up photographs of Andromeda, the satellite is only around 6,500 light-years across, but is joined by a supermassive black hole more than a million times the mass of the Sun, which is an extremely massive core for such a galaxy. small, suggesting it may have been larger in the past given its mass.

From the central black hole, scientists believe that M32 may have once been its own spiral or lenticular galaxy, even larger than the triangle galaxy, but ultimately not large enough to survive its encounter with its host, as that the two galaxies were a short distance from each other. The fated protogalaxy had its peripheral stars absorbed by Andromeda, leaving only the dense galactic core attached to the supermassive black hole. It now appears as a small golden elliptical galaxy with an aging stellar population. m110 is another elliptical satellite galaxy of Andromeda larger than m32 at around 17,000 light years in diameter, very similar to the ancient m110, it is believed to have interacted with Andromeda in the past.

Scientists have detected faint dusty, metal-rich fringes within Andromeda's halo that are believed to be formed by stars stripped from the satellite galaxy when it entered. reach of andromeda imagine what it would be like to live inside m110 you would see the vast side of andromeda in the galactic disk consume your sky at night just think of the historical, social and religious implications if early humans had seen something like this hanging finally in their ancient sky There is Messier 33, also known as the Triangle galaxy. He is currently the third largest member of the local group. A dwarf spiral galaxy about 60,000 light years in diameter.

It is not known if M33 is a true Andromeda satellite. It may just be your own galaxy, what happens. It would be located about 750,000 light years away, but in any case the two galaxies have definitely interacted in the last billion years and the data suggests that they will interact again in the future with the 40 billionstars of the triangle galaxy destined to be absorbed into a new galaxy or to be banished completely from the local group finally after millions of light years on this dark and lonely journey we reach the outer edge of the Andromeda galaxy once we have passed through From the plasma halo we reach the densest extended stellar disk formed composed of stars scattered by Andromeda's past collisions, once we have gone through all that, we will finally reach the visible component of the galaxy, the barred spiral structure rich in dust, gas and metals, similar to the Milky Way, but unlike it, the spiral structure of Andromeda is more complicated as it has been deformed by billions of years of gravitational interactions with galaxies such as the triangle, among others.

In 1998, ESA's infrared telescope suggested that Andromeda could be transitioning toward a ring galaxy, as dust from its body appears to be clustered in overlapping rings at various distances from the nucleus, studies conducted in the years since. NASA's Spitzer telescope has shown two spiral arms that extend from the central bar and beyond the rings, but are fractured into seven spiral segments separated by junctions of enhanced hydrogen gas where vigorous star formation occurs. ngc 206 is one such region Andromeda's largest star-forming cloud situated on a boundary between two of its southwestern spiral arms at around 4,000 light-years in diameter is one of the largest clouds of its type in the entire local group. and contains a cluster of more than 300 luminous blue supergiant stars with diameters dozens of times larger than that of the sun and ngc 206 is not the only place where we find clusters in andromeda, in fact we have identified more than 460 globular clusters within its limits, More than triple the number discovered in our own galaxy, the most significant of these clusters is Male 2.

It is the most massive cluster known in Andromeda and contains several million luminous stars of different ages and metallizations. The massive luminosity and general disparity in its stellar population implies that Male 2 may not be a true. globular cluster and may actually be the broken heart of a protogalaxy in a similar way to m32, but on a smaller scale, the outer layers of male 2 were torn off and dissolved into the fields of andromeda, but its galactic core managed to stay together by its central intermediate-mass black hole of 20,000 solar masses and so now these surviving stars cling to the black hole while their barrels around the galaxy appear as a surrogate globular cluster hiding the secrets of a richer past.

Andromeda's stellar population appears broadly in line with the Milky Ways containing young and old stars, clusters, nebulae, black holes and perhaps life-sustaining worlds around stars like the sun, unfortunately m31 is too distant for us to concentrate on the planetary systems of their stars, we can't even do that. However, within our own galaxy, despite the odds, in 1999 scientists thought they had detected indirect evidence of a planet within Andromeda when a microlensing event was detected. Microlensing occurs when light from a light source is bent very slightly as it travels toward Earth by gravity. of a planetary-mass object One possible explanation for this Andromeda-based microlensing signal called pa99n2 was that the light from a red giant star was being warped by a surrounding exoplanet with a mass six times that of Jupiter, unfortunately, however , microlensing events often occur due to unpredictable possibilities. alignments, so it's unlikely we'll ever be able to pick up this same signal again to follow up on, but even if it's not the result of an exoplanet, we can still say with relative certainty that Andromeda, like the Milky Way, is home to thousands of millions of planets orbiting their stars, many of which will be sun-like and suitable for supporting Earth-like worlds, in addition to living stars, we have also found dead stars within Andromeda.

Our search for The most important black hole is, of course, the one located in the center of the galaxy in The place where we find one of the most peculiar characteristics of Andromeda: its dense galactic core is divided into two regions classified as a double nucleus with the two nuclei called p1 and p2. p1 is the brightest concentration of matte, but it is believed to be displaced from the center. be a blanket of bright stars orbiting the inner core, in contrast, the less luminous concentration p2 is located in the center and contains the supermassive Andromeda black hole that drives its galactic tide.

The black hole is estimated to be more than a hundred million times the mass of the sun, significantly more massive than the central supermassive black hole of the Milky Way, Sagittarius, a star that has only about 4 million solar masses. The reason for this disparity, as So many other features of Andromeda, it is probably the product of its past collisions, as Andromeda has swallowed other galaxies. Mergers have supplemented its central black hole with an abundance of gas and matter, so m31's black hole has consumed much more mass than the Sagittarius star over its lifetime, culminating in this overwhelmingly large beast housed in the core. fractured composite galactic.

The journey to Andromeda is long and currently impassable for us humans; even if we could escape the gravity of the Milky Way, the time required to travel even one light year would far exceed the span of a lifetime; However, while we may not be able to reach Andromeda, we may not. After all, it is necessary to do so, since within a few billion years Andromeda will reach us. When studying images of the galaxy, a striking aspect of Andromeda is its bluish tint, but this is not a result of the natural color of the galaxy's starlight; in fact, it is being caused. by a phenomenon known as blue shift, one of the two types of Doppler shift.

Doppler shift occurs when waves traveling toward an observer are deformed by the motion of the object that emits them. They think that ambulances and police car sirens sound different when they approach us than when they move away. This is because approaching sound waves are bunched together while trailing ones are stretched out. The same phenomenon applies to light traveling through space. If an object moves away from us, its light will shift toward the red end of the spectrum and the galaxy will redshift. Most galaxies in space are redshifted because the expansion of the universe is moving them further away over time. but in the same way, an object moving through space towards us will have its light waves compressed, making them appear blue.

What does this mean? is that Andromeda's aesthetic blue tint is indicative that it is heading directly towards us at speeds of around 110 kilometers per second, the reason is that while the expansion of the universe separates most galaxies, Andromeda and the rest of the group local are close enough to us that they will be attracted by the gravity of the Milky Way, so over the next billion years the contents of the local group will merge into a single object beginning with the head-on collision of the Milky Way and andromeda in the next two billion years andromeda will subtly grow in the night sky increases in size until it becomes larger and brighter than the moon and every other object in the night sky within 3 billion years will occupy a considerable portion of our field of view, its light and its gas will extinguish the view of the universe behind, of course.

Barring some kind of miraculous engineering, Earth will have long been uninhabitable due to the evolution of the Sun, but if anything else in the solar system manages to survive so far into the future, it will see its sky clouded and illuminated by a messy asymmetric galaxy. . collision in four billion years the two galaxies will have collided with each other fundamentally deforming their spiral structures and dispersing their gases after the initial impact the cause of the two galaxies will spin again and again until they merge in the center with each iteration Hundreds of billions of stars will be rippled by gravity and sent cascading in all directions, but despite the large number of stars involved, it is statistically unlikely that two will collide, since the space between the stars is incomparably larger than the stars themselves.

As they pass within range of each other wreaking havoc on the orbits of their finely balanced planetary systems, the fate of the solar system ultimately depends on its position during and after the merger. Dozens of simulations have been run to determine a final resting place for the sun, but there is no clear consensus: on the one hand, the solar system could be ejected considerably further away, perhaps within the boundaries of Andromeda, or such. perhaps even expelled into intergalactic space; Alternatively, the sun could be thrown into the heart of the new galaxy's turret, where it could be torn away. fragments as it approaches the core, within about seven billion years the merger events will be completed with the merger of the core of each galaxy, that is, when their two black holes collide, these supermassive black holes will gradually begin to orbit each other as they use their dynamics. energy to catapult the stars out of their way, their orbits will decay and sink towards the center when they are a light year away from each other, they will begin to lose energy in the form of gravitational waves that will generate immense tidal waves that will be felt by thousands of millions. of light years through space, finally these two black holes will merge in the center creating a new supermassive black hole that will unite the heart of the new galaxy and after this the final phase of the evolution of the local group will have begun: a new supergiant elliptical galaxy whose unoriginal name Milcomodo galaxy collisions like this one are common throughout the universe and have played an important role in the formation of rich and diverse spiral galaxies suitable for habitable worlds like ours, but this cycle of collisions and Mergers have a limit and once the elliptical galaxy has taken shape, it will not change its morphology much from there, but will gradually absorb the rest of its satellite galaxies over billions of years, including the triangle galaxy it will likely orbit. the new galaxy Meanwhile, it will be more than 150 billion years before the last members of the local group have been consumed by this monster galaxy, but once they do, it will be that way forever, long before that happens.

The star-forming gases within Andromeda and the Milky Way have been depleted, and there will be less left for Milcomodo to repopulate its stars when it finally forms. While the elliptical galaxy is projected to undergo a productive starburst phase, vigorous star formation, this phase will be brief and less fruitful than those we have seen in other elliptical galaxies, without new stars to accompany the old ones, the stellar population milkomeda general will age. an increasing proportion of its stars progress towards the red giant phase, where they will explode or evolve into white dwarfs. As this happens, the expansion of the universe will accelerate, pushing galaxies beyond the local group, far out of reach, ultimately destined to become undetectable. will never find or even see another large galaxy again and, barring some small minor mergers within the remaining dwarf galaxies of the local group, the milk commodore will run out of rejuvenation mechanisms to keep itself replenished, the galaxy will stagnate and begin to die out, That will happen incredibly slowly over tens of billions of years, in fact, but the galaxy's stars will eventually cool to a temperature of just 5 kelvin, at which point they will no longer be hot enough to stay luminous and will freeze into solid spheres. and impenetrable of matter during their life. -giving elements locked inside it little by little our galaxy will become darker and dimmer and once the last star has faded the story of Andromeda and the Milky Way will be over, fortunately humanity was born in the middle of this great story Galactic galaxy long after its chaotic opening and long before its eternally depressing end, the story of Andromeda is more intertwined with the Milky Ways than people like Al Sufy Curtis Shapley and Hubblecould have imagined and since it's only been about 100 years since we realized that m31 was another galaxy, imagine what incredible knowledge our descendants will discover in the next century.