The Holographic Galaxy - Fractal Electron Vortex Black Holes Holograms Filaments Universe

A STUDENT FOUND SOME MISSING MASS, by detecting the soft x-rays emissions in WHIM filaments, which doesn't mean that the "Missing mass of the Universe" has been found. This remake story doesn't make front page headlines in the world, because even the big-bang theory predicted lots of missing baryonic mass to be in the WHIM, in addition to devising dark matter. The discovery by Pimbblet is fundamentally the same story published in May 2010, when Taotao Fang discovered "The Missing Mass of the Universe.", already described & poorly interpreted, to support the work in big-bang collaboration. The better interpretation of these findings, is that lots of more filaments have not yet been detected, & its very likely that the WHIM pervades & permeates throughout all large-scale structures in the Universe. Gudel observed Plasma flowing from the Orion Nebula in to the adjoining ISM, & then in to superbubble Eridanus. Very likely Plasma Flows through whole Galaxies throughout the Universe. Taotao Fang is the professional authority on the WHIM, & saw right through a large filament connecting the sculptor wall of galaxies, with a blazer & large black hole. The WHIM is basically transparent, having a low density of 6 protons per cubic meter, & high temp ~1 million degrees. Fang said, "the WHIM is difficult to detect, being so diffuse & straightforward to see right through." "Most astronomers search for obscured things, but they are looking through the WHIM on a regular basis," states Fang.  Visible light observation of large length filaments, requires exact line of sight alignments, to see right through a filament, that is far more large then it is wide. Even Pimbblet states that half of the atomic matter mass in the Universe could be in the WHIM. Most of the mass in the Universe was already known to be in filaments.
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Galaxy groups and clusters

 

Galaxy groups & clusters are the largest known gravitationally bound objects to have arisen thus far in the technique of cosmic structure formation.[1] They form the densest part of the huge scale structure of the universe. In models for the gravitational formation of structure with chilled dark matter, the smallest structures collapse first  finally build the largest structures, clusters of galaxies. Clusters are then formed comparatively recently between ten billion years ago & now. Groups & clusters may contain from0 to thousands of galaxies. The clusters themselves are often associated with larger, non-gravitationally bound, groups called superclusters.

Galaxy formation and evolution

The study of galaxy formation & evolution is concerned with the processes that formed a heterogeneous universe from a homogeneous beginning, the formation of the first galaxies, the way galaxies alter over time the processes that have generated the variety of structures observed in nearby galaxies. It is of the most active research areas in astrophysics.

Galaxy formation is hypothesized to occur, from structure formation theories, because of tiny quantum fluctuations in the aftermath of the Massive Bang. The simplest model for this that is in general agreement with observed phenomena is the  Cold Dark Matter cosmology; that is to say that clustering & merging is how galaxies gain in mass, & can also choose their shape & structure.

Galaxy Levels

This set was created thus:

he first level is "The Absolute", followed by "All Worlds", "All Suns", "Sun", "All Planets", "Earth", "Moon", and "The Absolute".

This lineage indicates and compares the construction of all of the levels, matters, and laws of the Universe, placing them in scale with another.

  * The heaviest/last level - "The Absolute",
  * Earth's satellite - "The Moon",
  * our planet - "Earth",
  * all of the planets in the solar method to which Earth belongs to - "All Planets",
  * the planets belong to the "Sun" or the solar method,
  * the Sun belongs to the Milky Way galaxy or the "All Suns" combined,
  * all galaxies put together belong to "All Worlds",
  * and all Worlds form a final whole called "The Absolute"

Solar System

The Solar Technique is also home to regions populated by smaller objects. The asteroid belt, which lies between Mars and Jupiter, is similar to the terrestrial planets as it consists chiefly of rock and metal. Beyond Neptune's orbit lie trans-Neptunian objects composed mostly of ices such as water, ammonia and methane. Within these regions, individual objects, Ceres, Pluto, Haumea, Makemake and Eris, are recognized to be huge to have been rounded by their own gravity, and are thus termed dwarf planets.[e] In addition to thousands of little bodies[e] in those regions, various other little body populations, such as comets, centaurs and interplanetary dust, freely travel between regions.

The Solar System[a] consists of the Sun and the astronomical objects bound to it by gravity, all of which formed from the collapse of a huge molecular cloud about two.6 billion years ago. Of the plenty of objects that orbit the Sun, most of the mass is contained within two comparatively solitary planets[e] whose orbits are  circular and lie within a virtually flat disc called the ecliptic plane. The smaller inner planets, Mercury, Venus, Earth and Mars, also called the terrestrial planets, are primarily composed of rock and metal. The outer planets, the gas giants, are substantially more huge than the terrestrials. The largest, Jupiter and Saturn, are composed chiefly of hydrogen and helium; the outermost planets, Uranus and Neptune, are composed largely of ices, such as water, ammonia and methane, and are often referred to separately as "ice giants".Six of the planets and of the dwarf planets are orbited by natural satellites,[b] usually termed "moons" after Earth's Moon. Each of the outer planets is encircled by planetary rings of dust and other particles.

The solar wind, a flow of plasma from the Sun, creates a bubble in the interstellar medium known as the heliosphere, which extends out to the fringe of the scattered disc. The hypothetical Oort cloud, which acts as the source for long-period comets, may also exist at a distance roughly a thousand times further than the heliosphere.

HII Regions

The SDSS has  definitely seen hundreds of HII regions in nearby galaxies. But using the SDSS to study HII regions presents an issue. Because the SDSS sees so plenty of objects in the sky, the survey makes use of a computer program called Picture to classify the objects as stars, galaxies, cosmic rays, ghosts (false optical images), or moving objects. Overall, Picture does an excellent job of identifying the objects SDSS sees.

Most spiral galaxies contain star-forming regions rich in ionized hydrogen. Ionized hydrogen is also called HII, so the star forming regions are known as "HII (pronounced 'H-two') regions." Because stars are actively forming inside HII regions, astronomers are interested in studying the regions.

But, nearby spiral galaxies that appear giant in our field of view cause issues for Picture. When Picture examines a galaxy like the below, in lieu of classifying it as galaxy, Picture breaks it up in to several parts! Picture often mistakes the core and the HII regions in a galaxy for separate galaxies. Sometimes Picture can look at a single galaxy and mistakenly see up to four separate galaxies.The next version of Picture ought to fix the issue of HII region misidentification. But until astronomers know how lots of regions have been misidentified by the current version of Picture, they will never know whether the next version is actually an improvement. & although astronomers agree that a catalog of misidentified HII regions is important to checking the accuracy of the survey, none of them has made such a catalog. You can help.

To tell the difference between a single galaxy with misidentified HII regions & genuine multiple galaxies, a program called Plate selects objects for the SDSS will measure spectra. The SDSS cannot measure spectra for all the objects it sees, so Plate selects which objects to examine. Sometimes Plate selects HII regions for spectral analysis. By taking a look at both images & spectra for the same galaxy, you can tell which places are HII regions misidentified by Picture, & which are actually separate galaxies.

Your mission, ought to you select to accept it, is to find the HII regions for which the SDSS has acquired spectra. This information will let you study HII regions in detail, learn how well our Picture program works, & give us a comparison for when they start using a brand spanking new, & hopefully improved, version of Picture.

The only way to be definite you have identified an HII region is to visually inspect the SDSS field that contains the galaxy. Information Release six (the information you see on SkyServer) contains spectra of over 350,000 galaxies, so you cannot visually inspect every. Additionally, some of the galaxies are very small, & it can be hard to tell what you are seeing, so you require other proof to tell whether you are taking a look at an HII region or a whole galaxy. This method may appear tedious, but it is an important part of astronomy: SDSS astronomers have visually inspected hundreds of galaxies for papers they have written.

Types of Stars

Classification lies at the foundation of  every science. Scientists create classification systems based on the patterns they see. For example:

When astronomers look through their telescopes, they see billions of stars. How do they make sense of all of them?

Astronomers are no different. They classify planets by their composition (rocky planets or gas giants), galaxies by their shape (spiral, elliptical or irregular), & stars by their spectra.

  * Biologists classify plants & animals in to groups based on their structure
  * Geologists classify rocks & minerals by their origins
  * Chemists classify compounds by what elements they contain

Classifying star spectra was a key step for astronomers in discovering how stars work. Thus, in astronomy as well as other sciences, the seemingly ordinary step of classifying things finally yields critical insights in to our world.

Galaxy Collisions

Many galaxies are members of groups or clusters. Since groups and clusters contain so lots of galaxies comparatively close together, it ought to not be surprising that galaxies sometimes collide with each other. In fact, the Milky Way Galaxy is colliding with the Sagittarius Dwarf Galaxy right now (see the SDSS First Discoveries for more information). Although galaxy collisions are common, stars in each galaxy are so far apart that collisions between stars are rare.

Even if galaxies don't actually collide, though, they can still affect another. When galaxies pass close to another, the force of gravity they exert on another may cause both galaxies to bend out of shape. Both crashes and near misses between galaxies are often called "interactions."When galaxies interact, clouds of gas inside each galaxy may become compressed. Compressing the clouds may cause them to collapse under their own gravity, turning in to stars. This process can lead to a burst of star formation in interacting galaxies, leaving a new generation of stars in a galaxy where normal star formation may have ceased long ago.

At the right, you can see galaxies interacting. You can see they are being distorted by the gravitational interaction between them. Are you able to imagine what they might have looked like before they interacted?

Galaxy collisions take hundreds of millions of years, so they cannot watch them happen. In lieu, they use computer simulations to show us what would happen if galaxies collided in a sure way. In case you are interested in learning about galaxy collisions, you can use a web-based simulation tool to model them.

Planet

The term planet is ancient, with ties to history, science, mythology, & religion. The planets were originally seen by lots of early cultures as divine, or as emissaries of the gods. As scientific knowledge advanced, human perception of the planets changed, incorporating a lot of disparate objects. In 2006, the International Astronomical Union officially adopted a resolution defining planets within the Solar Method. This definition has been both praised & criticized, & remains disputed by some scientists.

A planet "wandering star") is a celestial body orbiting a star or stellar remnant that is large to be rounded by its own gravity, is not large to cause thermonuclear fusion, & has cleared its neighbouring region of planetesimals.[a][1][2]

The planets were thought by Ptolemy to orbit the Earth in deferent & epicycle motions. Though the idea that the planets orbited the Sun had been suggested lots of times, it was not until the 17th century that this view was supported by facts from the first telescopic astronomical observations, performed by Galileo Galilei. By cautious analysis of the observation information, Johannes Kepler found the planets' orbits to be not circular, but elliptical. As observational tools improved, astronomers saw that, like Earth, the planets rotated around tilted axes, & some shared such features as ice-caps & seasons. Since the dawn of the Space Age, close observation by probes has found that Earth & the other planets share characteristics such as volcanism, hurricanes, tectonics, & even hydrology.Planets are usually divided in to main types: giant, low-density gas giants, and smaller, rocky terrestrials. Under IAU definitions, there's three planets in the Solar System. In order of increasing distance from the Sun, they are the terrestrials, Mercury, Venus, Earth, and Mars, then the gas giants, Jupiter, Saturn, Uranus, and Neptune. Four of the planets are orbited by or more natural satellites. Additionally, the Solar System also contains at least dwarf planets[3] and hundreds of thousands of little Solar System bodies.

Since 1992, hundreds of planets around other stars ("extrasolar planets" or "exoplanets") in the Milky Way Galaxy have been discovered. As of December 2010, over 500 known extrasolar planets are listed in the Extrasolar Planets

De Vaucouleurs system

The de Vaucouleurs technique for classifying galaxies is a widely used extension to the Hubble sequence, first described by Gérard de Vaucouleurs in 1959.[2] De Vaucouleurs argued that Hubble's two-dimensional classification of spiral galaxiesâbased on the tightness of the spiral arms and the presence or absence of a bar did not adequately describe the full range of observed galaxy morphologies. In particular, he argued that rings and lenses were important structural parts of spiral galaxies.[3]

The de Vaucouleurs technique retains Hubbles basic division of galaxies in to elliptical s, lenticulars, spirals and irregulars. To complement Hubbleâs technique, de Vaucouleurs introduced a more elaborate classification technique for spiral galaxies, based on morphological characteristics:

  * Bars. Galaxies are divided on the basis of the presence or absence of a nuclear bar. De Vaucouleurs introduced the notation SA to denote spiral galaxies without bars, complementing Hubbleâs use of SB for barred spirals. He also allowed for an intermediate class, denoted SAB, containing weakly barred spirals. Lenticular galaxies are also classified as unbarred (SA0) or barred (SB0), with the notation S0 reserved for those galaxies for which it is impossible to tell if a bar is present or not (usually because they are edge-on to the line-of-sight).
# Rings. Galaxies are divided in to those possessing ring-like structures (denoted â) & thse without rings (denoted â(s)â. So-called âtransitionâ galaxies are given the symbol (rs).
# Spiral arms. As in Hubbleâs original system, spiral galaxies are assigned to a class based primarily on the tightness of their spiral arms. The de Vaucouleurs system extends the arms of Hubbleâs tuning fork to include several additional spiral classes:

  * Sd (SBd) - diffuse, broken arms made up of individual stellar clusters & nebulae; faint central bulge
  * Sm (SBm) - irregular in appearance; no bulge part
  * Im - highly irregular galaxy

Most galaxies in these classes were classified as Irr I in Hubbleâs original system. In addition, the Sd class contains some galaxies from Hubbleâs Sc class. Galaxies in the classes Sm & Im are termed the âMagellanicâ spirals & irregulars, respectively, after the Magellanic Clouds. The Giant Magellanic Cloud is of type SBm, while the Little Magellanic Cloud is an irregular

Hubble sequence

The Hubble sequence is a morphological classification process for galaxies invented by Edwin Hubble in 1936.[1] It is often known colloquially as the Hubble tuning-forkâ because of the shape in which it is historicallyin the past represented. Hubbleâs process divides galaxies in to three broad classes based on their visual appearance:

* Elliptical galaxies have smooth, featureless light distributions and appear as ellipses in images. They are denoted by the letter E, followed by an integer n representing their degree of ellipticity on the sky.
  * Spiral galaxies consist of a flattened disk, with stars forming a (usually two-armed) spiral structure, and a central concentration of stars known as the bulge, which is similar in appearance to an elliptical galaxy. They are given the symbol S. Roughly half of all spirals are also observed to have a bar-like structure, extending from the central bulge. These barred spirals are given the symbol SB.
  * Lenticular galaxies (designated S0) also consist of a bright central bulge surrounded by an extended, disk-like structure but, unlike spiral galaxies, the disks of lenticular galaxies have no visible spiral structure and are not actively forming stars in any significant quantity.
The Hubble sequence is often represented in the type of a two-pronged fork, with the ellipticals on the left (with the degree of ellipticity increasing from left to right) and the barred and unbarred spirals forming the parallel prongs of the fork. Lenticular galaxies are placed between the ellipticals and the spirals, at the point where the prongs meet the âhandleâ.

These broad classes can be extended to enable finer distinctions of appearance and to encompass other types of galaxy, such as irregular galaxies, which have no obvious regular structure (either disk-like or ellipsoidal).

To this day, the Hubble sequence is the most often used method for classifying galaxies, both in professional astronomical research and in amateur astronomy.

Galaxy morphological classification

Galaxy morphological classification is a process used by astronomers to divide galaxies in to groups based on their visual appearance. There's several schemes in use by which galaxies can be classified according to their morphologies, the most famous being the Hubble sequence, devised by Edwin Hubble and later expanded by Gérard de Vaucouleurs and Allan Sandage.

Galaxy formation and evolution

Galaxy formation is hypothesized to occur, from structure formation theories, because of tiny quantum fluctuations in the aftermath of the Large Bang. The simplest model for this that is in general agreement with observed phenomena is the  Chilled Dark Matter cosmology; that is to say that clustering and merging is how galaxies gain in mass, and can also select their shape and structure.

The study of galaxy formation and evolution is concerned with the processes that formed a heterogeneous universe from a homogeneous beginning, the formation of the first galaxies, the way galaxies modify over time, and the processes that have generated the variety of structures observed in nearby galaxies. It is of the most active research areas in astrophysics.

Galaxy color magnitude diagram

The Galaxy color-magnitude diagram shows the relationship between absolute magnitude, luminosity, & mass of galaxies. A preliminary description of the areas of this diagram was made in 2003 by Eric F. Bell et al. from the COMBO-17 survey[1] that clarified the bimodal distribution of red & blue galaxies as seen in analysis of Sloan Digital Sky Survey data[2] & even in de Vaucouleurs' 1961 analyses of galaxy morphology[3] Noticed in this diagram are main features: the red sequence, the green valley, & the blue cloud. The red sequence includes most red galaxies which are usually elliptical galaxies. The blue cloud includes most blue galaxies which are usually spirals. In between the distributions is an underpopulated space known as the green valley which includes plenty of red spirals. Unlike the comparable HertzsprungRussell diagram for stars, galaxy properties are not necessarily determined by their location on the color-magnitude diagram. The diagram also shows considerable evolution through time. The red sequence earlier in evolution of the universe was more constant in color across magnitudes & the blue cloud was not as uniformly distributed but showed sequence progression.

Galaxy Science Fiction

Galaxy Science Fiction was an American digest-size science fiction journal, published from 1950 to 1980. It was founded by an French company, World Editions, which was looking to break in to the American market. World Editions hired as editor H. L. Gold, who quickly made Galaxy the leading science fiction (sf) journal, focusing on tales about social issues than know-how.

Gold published plenty of notable tales in the coursework of his tenure, including Ray Bradbury's "The Fireman", later expanded as Fahrenheit 451; Robert A. Heinlein's The Puppet Masters; & Alfred Bester's The Demolished Man. In 1952, the journal was acquired by Robert Guinn, its printer. By the late 1950s, Frederik Pohl was helping Gold with most aspects of the magazine's production. When Gold's health worsened, Pohl took over as editor, beginning officially at the finish of 1961, though he had been doing all of the production work for some time.Under Pohl Galaxy had continued success, regularly publishing fiction by major writers such as Cordwainer Smith, Jack Vance, Harlan Ellison, & Robert Silverberg. However, Pohl seldom won the annual Hugo Award for his stewardship of Galaxy, winning Hugos in lieu for its brother journal, If. In 1969 Guinn sold Galaxy to Universal Publishing & Distribution Corporation (UPD) & Pohl resigned, to get replaced by Ejler Jakobsson. Under Jakobsson the journal declined in quality. It recovered under James Baen, who took over in mid-1974, but when they left at the finish of 1977 the deterioration resumed, & there were financial problemsâwriters were not paid on time & the schedule became erratic. By the finish of the 1970s the gaps between issues were lengthening, & the title was finally sold to Vincent McCaffrey, who brought out issue in 1980. A brief revival as a semi-professional journal followed in 1994, edited by H. L. Gold's son, E. J. Gold; this lasted for three bimonthly issues.

Evolution

Evolution (also called biological or organic evolution) is the change over time in or more inherited traits present in populations of organisms.[1] Inherited traits are particular distinguishing characteristics, including anatomical, biochemical or behavioural characteristics, that are passed on from generation to the next. Phenotypic expressions of these traits can be influenced by geneenvironment interactions. Evolution may occur when there is variation of inherited traits within a population. The major sources of such variation are mutation, genetic recombination and gene flow.[2][3][4][5] Evolution has led to the diversification of all living organisms, which are described by Charles Darwin as "endless forms most stunning and most wonderful".
In speciation, a single ancestral species splits in to or more different species. Speciation is visible in anatomical, genetic and other similarities between groups of organisms, geographical distribution of related species, the fossil record and the recorded genetic changes in living organisms over lots of generations. Speciation stretches back over four.5 billion years in the coursework of which life has existed on earth.[9][10][11][12] It is thought to occur in multiple ways such as slowly, steadily and gradually over time or quickly from long static state to another.

Two processes are usually distinguished as common causes of evolution. is natural choice, a process in which there is differential survival and/or reproduction of organisms that differ in or more inherited traits.[1] Another cause is genetic drift, a process in which there's random changes to the proportions of or more inherited traits within a population.[7][8]

Elliptical Galaxy

An elliptical galaxy is a galaxy having an about ellipsoidal shape as well as a smooth, very featureless brightness profile. They range in shape from very spherical to highly flat & in size from hundreds of millions to over trillion stars. They can be the result of galaxies colliding.

Elliptical galaxies are of the main classes of galaxy originally described by American astronomer Edwin Hubble in his 1936 work The Realm of the Nebulae,[1] along with spiral & lenticular galaxies. Elliptical galaxies are (together with lenticular galaxies) also called "early-type" galaxies (ETG), due to their location in the Hubble sequence.

Most elliptical galaxies are composed of older, low-mass stars, with a sparse interstellar medium & minimal star formation activity. They are surrounded by giant numbers of globular clusters. Elliptical galaxies are believed to make up about 1015% of galaxies in the local Universe[2] but are not the dominant type of galaxy in the universe overall. They are preferentially found close to the centers of galaxy clusters[3] & are less common in the early Universe.

Spiral Galaxies

In the event you can clearly see the spiral shape, the galaxy is called a "face-on spiral." In the event you in lieu see the galaxy from the side, it is called an "edge-on spiral." You can recognize edge-on spiral galaxies because you can see their bright central bulges. Face-on and edge-on spiral galaxies are not any different; they only look different because of the angle from which you see them.

The most common type of galaxy is called a "spiral galaxy." Not surprisingly, spiral galaxies look like spirals, with long arms winding toward a bright bulge at the middle. But be cautious - in the event you looked at a spiral galaxy from the side, you could mistake its shape for a circle, and so you'd must make use of other criteria to learn it was a spiral.

About 77% of the observed galaxies in the universe are spiral galaxies. Our own galaxy, the Milky Way, is a typical spiral galaxy.

Some spiral galaxies have arms that are wound tightly, while other galaxies have loosely-wound arms. The difference between tightly and loosely wound spirals is a actual difference between the galaxies, and can be used to classify spirals.
Some spiral galaxies have a bright line, or bar, walking through them. These are called "barred spiral galaxies.
The arms of a spiral galaxy have lots of gas and dust, and they are often areas where new stars are constantly forming. The bulge of a spiral galaxy consists primarily of elderly, red stars. small star formation goes on in the bulge

Spiral galaxies are further classified by how tightly their spiral arms are wound. A galaxy with tightly wound arms, such the left galaxy in the list above, would be called "type a." galaxy A "type b" galaxy has more loosely wound arms. A "type c" galaxy (such as the middle above) has loosely wound arms. What type do you think the barred spiral to the right would be?

What is galaxy ?

A spiral galaxy centers around a hub, which is roughly spherical & bulges outward from the disk. The hub is the gravitational middle of the galaxy, & usually contains a supermassive black hole. Surrounding the hub are spiral arms, which are bunched-up waves of stars & gas orbiting the middle. The spiral arms usually have more gas & dust, & they contain most of the newly formed stars, which make them appear blue in color imagery. A spiral galaxy may have a horizontal bar passing through its hub; our own galaxy, the Milky Way, is believed to contain a bar.

A galaxy is a cluster of stars, nebulae, dark matter, & other astronomical objects. Most galaxies are tens of thousands of light years in diameter,  contain billions of stars. Galaxies come in primary shapes; spiral galaxies are narrow disks, with spiral arms surrounding a central hub; elliptical galaxies are uniform, oval-shaped agglomerations;  irregular galaxies have tiny or no positive structure.
Elliptical galaxies have a massive, central hub, but they lack the arms of a spiral galaxy; they usually appear more yellowish in color imagery from elderly, reddish stars. Irregular galaxies often have no discernible structure, but often they can be recognized as having a distorted spiral or elliptical shape. Elliptical and irregular galaxies often result from collisions, which cause massive bursts of star formation and distort the galaxies' structure due to the complex gravitational interactions. Finally, the galaxies usually combine to form massive galaxy, which has cast off most of its gas and dust clouds.

There's roughly a hundred billion galaxies in the visible universe; most of them occur in massive agglomerations called galaxy superclusters. Between these superclusters are voids with few or no galaxies, often for a hundred million light years or more. By studying the rotation of spiral galaxies, astronomers found that most of the matter in the universe is not stars and gas, but invisible �dark matter� which cannot be seen but still exerts gravity. Dark matter is thought to be responsible for these massive clusters, as the gravitational attraction of the dark matter pulled galaxies together.

Galaxy Information

A galaxy is a large, gravitationally bound method that consists of stars & stellar remnants, an interstellar medium of gas dust, & an important but poorly understood part tentatively dubbed dark matter.[1][2] The name is from the ancient Greek word galaxias , literally meaning "milky", a reference to the Milky Way galaxy. Typical galaxies range from dwarfs with as few as0 million (107) stars,[3] up to giants with a hundred trillion (1014) stars,[4] all orbiting the galaxy's middle of mass. Galaxies may contain lots of star systems, star clusters, & various interstellar clouds. The Sun is of the stars in the Milky Way galaxy; the Solar Method includes the Earth & all the other objects that orbit the Sun.

Historically, galaxies have been categorized according to their apparent shape (usually known as their visual morphology). A common form is the elliptical galaxy,[5] which has an ellipse-shaped light profile. Spiral galaxies are disk-shaped assemblages with dusty, curving arms. Galaxies with irregular or unusual shapes are known as irregular galaxies, and usually result from disruption by the gravitational pull of neighboring galaxies. Such interactions between nearby galaxies, which may ultimately lead to galaxies merging, may induce episodes of significantly increased star formation, producing what is called a starburst galaxy. Small galaxies that lack a coherent structure could even be known as irregular galaxies.

Although it is not yet well understood, dark matter appears to account for around 90% of the mass of most galaxies. Observational information suggests that supermassive black holes may exist at the middle of lots of, if not all, galaxies. They are proposed to be the primary cause of active galactic nuclei found at the core of some galaxies. The Milky Way galaxy appears to harbor at least such object within its nucleus.

There are probably over 170 billion [one.7 � 1011] galaxies in the observable universe.7,8 Most galaxies are one,000 to 100,000(9) parsecs in diameter & are usually separated by distances on the order of millions of parsecs (or megaparsecs).10 Intergalactic space [the space between galaxies] is filled with a tenuous gas of an average density less than atom per cubic meter. all of galaxies are organized in to a hierarchy of associations called clusters, which, in turn, can form larger groups called superclusters. These larger structures are usually arranged in to sheets & filaments, which surround immense voids in the universe.11