The discovery of the vast universe, that exists outside our galaxy, began with Edwin Hubble’s discovery of a Cepheid Variable star in Andromeda, which he used to measure the distance to our neighbouring galaxy (Bennett et al. 109). This was instrumental in establishing Hubble’s law or the theory that the universe is expanding and galaxies are moving away from the Milky Way (Bennett et al. 109). However, Andromeda poses a contradiction; while other galaxies are moving away from the Milky Way, Andromeda is actually moving towards it and is set on a collision course with our galaxy. This paper will explore the different ways in which galaxies interact with each other, particularly focusing on galactic mergers. It will also analyze the impact of the Andromeda-Milky Way collision including the effect on existing objects in these galaxies such as stars and black holes, the creation of new bodies and the implication for the survival of life on Earth.
Galaxies interact with each other in three different ways depending on the mass ratio, collision angles, velocity and proximity of the galaxies (citation). First, a major merger occurs when two galaxies of nearly equal mass slowly pass close to each other (citation). Galaxy mergers have a monumental impact on the objects present in the interacting galaxies as it affects the black holes, disks of spiral galaxies and can result in formation of stars and a bright quasar in the new galaxy. The impact of these mergers will be discussed in more detail throughout this paper. The second way in which galaxies interact is through galactic cannibalism. This occurs when a massive galaxy swallows up stars from the smaller satellite galaxies that orbit it (Bennett et al. 630). Through galactic cannibal...
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... is very difficult for astronomers to predict events with absolute certainty; astronomers can only create probable simulations of different scenarios that could occur. While the exact details are still not known with certainty, the collision between Andromeda and the Milky Way will happen and the spiral galaxy we know and live in will transform into the giant elliptical, Milkomeda.
Works Cited
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Dubinski, John. "The Great Milky Way Andromeda Collision." Sky and telescope 112.4 (2006): 30-36.
Moore, Ben, et al. "Galaxy harassment and the evolution of clusters of galaxies." Nature 379 (1996): 613-616.
Two men named Harlow Shapley and Heber Curtis has a debate in 1920 that is still important today for changing how we think about galaxies. They talked about five important things. The first thing they debated was how big our galaxy, the Milky Way, is. Shapley said that the Milky Way was much bigger than we first thought, 100,000 light-years across, and that, because it was that big, it had to be the only one. Curtis said the the Milky Way was smaller than that, and that other galaxies existed past ours. They were both right and both wrong. Shapley was right about the size of the Milky Way, and Curtis was right about there being many more galaxies in the universe.
Throughout the ages, humans have been looking for a way to see into the past. In the year 1990, astronomers from NASA made this possible. Sending the Hubble Space Telescope into orbit with the space shuttle Discovery, NASA would make historical discoveries beyond their wildest dreams. Earlier this year they discovered a galaxy approximately 13 billion light years from Earth. Viewing the object at 750 million years after the big bang, scientists have looked into a time shortly after the "Dark Ages," a time before the first galaxies and quasars were formed. This incredible discovery was made with the aid of a cluster of galaxies known as Abell 2218. Being as massive as it is, Abell 2218 bends and amplifies any light that passes through it, working as a natural telescope ("Hubble"). The Hubble Space Telescope has become a great and valuable astronomic tool that NASA says is too costly and dangerous to keep running, a decision that may be premature.
Quasi-stellar radio sources, more commonly known as Quasars, are the most luminous, and some of the most powerful objects that we have ever observed in our universe. Although Quasars are beautiful to look at, the method that goes into creating them is a continuous process of death and destruction. Quasars may be billions upon billions of light years away, but that has not stopped them from having serious scientific implications, the most famous being that they have helped to prove The Big Bang Theory.
All galaxies contain star clusters. A star cluster is a group of stars held together by gravity. Open star clusters are collections of six to thousands of usually young stars. Globular clusters are ball-shaped collections of thousands to millions of very old stars. Galaxies are collections of millions to hundreds of billions of stars, planets, gas, and dust, measuring up to one hundred thousand ly across. They came in different shapes and sizes and are spread across the Universe. In the 1920’s, astronomer Edwin Hubble changed the way in which scientists view the Universe. The four types of galaxies that are categorized by shape are elliptical, spiral, lenticular, and irregular. Elliptical galaxy is a large group of stars that together make
Over 11 million light-years away from our tiny home planet is a massive galaxy named Centaurus A. This galaxy is one of the many located within the constellation, Centaurus. The image that I chose is of the center of Centaurus A but in this paper I will focus on the whole galaxy as well as the nucleus. In this paper I will be stating why I chose this image, sharing background information on this galaxy, what makes this galaxy so unusual, and the different stars and formations that have been discovered within this galaxy.
Dark Matter is next largest ingredient, which only interacts with the rest of the universe through its gravity. Astronomers believe that the Universe is critically balanced between being open and closed. They derive this fact from the observatio...
Choi, Charles Q. "The Expanding Universe: From the Big Bang to Today." Space.com. N.p., 21 Mar. 2013. Web. 05 Jan. 2014.
Comparing this galaxy’s size to are own Milky Way Galaxy, which is estimated to be around 8.5*1011 solar masses large, the Andromeda Galaxy is about 20% bigger then are own. Along with this we also know that both our own galaxy and this galaxy are on a collision course. It is estimated that in around 7.5 billion years that these two galaxies will merge together in a surely violent process. It is suspected that after this a large disc or elliptical galaxy will exist in the place of the once separate galaxies.
In 1912 the astronomer Vesto Slipher who studied the light spectrum of objects in space that first noticed the redness of other galaxies as they appeared the skies. Some years later in 1929 Carl Hubble discovered that the other galaxies are moving away from us. While studying the light from Type 1a supernova explosions he observed a Doppler effect in the light from the supernova the farther away the redder the light that he observed. A Type 1a supernova is a binary star system where a white dwarf star absorbs the gas of the other one and thermonuclear explosion when it get...
This suggests that in the past, galaxies were much closer to us than they are now: simply extrapolate the motion into the past. As it turns out, if this is performed, it indicates that all galaxies in the observable universe would have been at the same 'location' about 11 billion years ago: that is, all the matter in the universe originated from a single location. This is the (simplified) Big Bang theory. Actually, it's a little more complicated than that: according to general relativity, it's not really that distant galaxies are flying away from us, it's that space itself is expanding, increasing the distance. You can think of the universe as the surface of a balloon, with the balloon constantly expanding.
At the beginning of the course we were asked to choose a “Cosmic Target”, which is something in space that we wanted to know more about. I chose the Milky Way Galaxy as a single unit. I wanted to know why it was, what it was and where it was going. All of us of course know where the Milky Way is, it is our home. A part of our cosmic address, and up until recently it was the biggest thing that we could imagine. As far as where it is in the universe, it is in The Local group, which is a sub-cluster, located in the Virgo Super Cluster. All of this is somewhere around 13 Billion years after the Big Bang.
Space experts are still not totally beyond any doubt how different universes have or are framed, and took the numerous shapes that we see today. Despite the fact that they do have a few thoughts regarding the sources and advancement of these cosmic systems. There is a verbal confrontation between two particular speculations clarifying the development of systems. The first is that soon after the enormous detonation around 14 billion years prior, giving way gas and tidy mists may have lead to the development of systems. The second hypothesis, which has picked up quality as of late, says the youthful universe contained some little "irregularities" of matter, which bunched together to frame cosmic systems or that connections between worlds, particularly crashes between systems, assume a vital part in their advancement. Hubble Space Telescope has shot numerous such irregularities, which may be the forerunners to cutting edge systems. As indicated by this hypothesis, the greater part of the early extensive worlds were spirals. Be that as it may, after some time, numerous spirals converged to frame
This essay has provided some small glimpses into the fascinating world of stellar astronomy and stellar evolution. It has shown how a star is born and what its existence is like as a main sequence star. It has explored some of the most common final transformations and the resulting stellar remnants. This essay has also presented insight into a variety of the nuclear fusion reactions that take place as stars die and given the reader information about how long stars exist in various states. As one learns more about the lifecycle of stars, one cannot help but to be awed by the vast transformations and complex internal reactions that take place during their existence.
“Sheltered as we are by Earth's atmosphere and magnetic field, which deflect lethal radiation from space, we are like coddled children who have never ventured into a tough neighborhood” (Folger 2). Humans have been fascinated with space since the beginning of our time. Just like children and rough neighborhoods, we have tackled obstacle over obstacle to make it home again. In the end, we have a better knowledge and strength than before. The future of space exploration can assist us in answering the everlasting question of how the universe came to be. The more we explore the infinite galaxies, the more we can scientifically discover and create new technologies as science advances. As we continue to discover, we can create new fields and occupations for aspiring young students like myself.
Astronomers believe that most galaxies consist of a supermassive black hole at the center, which attracts all constituents of galaxies such as, dust, gases (mainly Hydrogen and Helium), atoms, stars, interstellar clouds and planets to the center by force of gravity, but are not sure whether all galaxies contain a black hole in the center. Galaxies keep moving in relative motion to one another and intermittently can come so close that the force of gravitational attraction between the galaxies may become strong enough to cause a change in the shape of the galaxies, while in exceptional cases, the galaxies may collide. If two galaxies collide, they may pass right through without any effect or may merge, forming strands of stars, extending beyond 100,000 light years in space (World Book Online Reference Centre, 2005). Hence, neighboring and often other colliding galaxies induce the sha...