Many people tend to point What are the types of galaxies that exist?, since visiting them and determining the shapes of the unequal galaxies has been a very regular center of study in thousands of explorations throughout humanity. In this article I will show you the different kinds of existing galaxies.
In this sense, treat the origin of the forms of the galaxies It is a question that perhaps many of us ask ourselves, however, scientists establish that if all the gas is transformed into stars before the gas has time to form a disk, then it becomes an elliptical galaxy. On the other hand, they define that if the gas has time to stabilize in the form of a disk before everything is used, it transforms into a spiral galaxy. If you want to delve deeper into the general characteristics of galaxies, you can read about the characteristics of galaxies.
On the other hand, some of the galaxies elliptical they are made of several galaxies that have merged. Investigations of distant galaxies show that spiral galaxies were more common in the past than they are today, so perhaps what once were spiral galaxies are now elliptical.
Either way, this is a site of active exploration. The difficulty is that most of the mass in galaxies is unreferenced, so we have a hard time understanding the dynamics of galaxy formation. You can also learn more about galaxy formation in the article detailing it. how galaxies and stars are formed.
Inquiries of galaxy classifications
Dealing with what are the types of galaxies that exist is a curious study since to know their state we must first start from certain inquiries regarding their classification since it has to do with the representation of the galactic center (the placement of stars in the center of the galaxy) and the disk (the distribution of arms) of the galaxy in argument. If you would like to know more about the types of galaxies in the universe, read on.
Spirals, as their nickname shows, have great disks and galactic centers of regular dimension. Ellipticals are essentially pure galactic centers with no disk. Irregulars do not have symmetrical representations, neither a center nor perceptible disks.
What are the types of galaxies that exist?
According to the Hubble telescope, in the Milky Way We can find four main types of galaxies, which are:
1.Galaxy elliptical
A common form is the elliptical galaxy which, as its nickname shows, has the glowing profile of a ellipse. They are devoid of gas and dust and are made up of old, yellow, low-metallicity stars. In other words, they are population II stars. It is presumed that all enormous elliptical galaxies have a supermassive black hole at their galactic center. This is a fascinating topic that can be explored further in the context of how black holes form.
Characteristics of the elliptical galaxy
Elliptical galaxies vary greatly in brightness, mass, and volume, going from the dwarf spheroidal girls, of particulars similar to those of a globular cluster, but very rich in dark matter. Their common characteristics are:
Missing or insignificant angular instant.
Lack or insignificant sum of interstellar matter (gas and dust), no young stars, no open heaps (except for exact inequalities like NGC 1275).
Center Light Gathering
In the "square" there is a lack of light gathering in its center while the "discoid" have more joint of light there.
Stellar populations
While the former are accommodated in stars old with greater heritage in loaded elements, in the latter there is little or no gain of such elements and their stars are younger (not much younger).
radio wave sources
elliptical galaxies «square» sometimes hold sources that cause strong manifestations of radio waves; in ring fingers this is much rarer.
light blue
The former usually have gas hot that can be discovered thanks to its X-ray manifestation, especially in the largest ones; in the latter it is much rarer to enjoy said gas.
Globular clusters and satellite galaxies
Magna elliptical galaxies usually have a work of globular mounds, double nuclei, and large sum of satellite galaxies. A possible definition is galactic cannibalism, that is, the impregnation of a smaller galaxy by a larger one, for example, our Milky Way is known to be "digesting" a pair of smaller galaxies today.
Origin of the elliptical galaxy
The usual picture of elliptical galaxies presents them as galaxies where the star creation ended after the initial outburst, now showing only old stars.
Some recent research has found clusters of young stars, Blues within some elliptical galaxies, along with other forms that can be represented by galaxy mergers. In the new view, an elliptical galaxy is the result of an extensive process where several smaller galaxies, of any size, collide and merge into a larger one. If you are interested in the impact these mergers have on galaxies, you can read the article on types of galaxies and their formation.
There are three formulas in which a galaxy elliptical from the collision between two previous galaxies: an encounter that astronomers frequent as wet in which there is exuberant cold gas and a stellar outbreak and another accredited as dry in which there is no gas or it is very little copious and therefore very little or no star creation action.
The first type causes elliptical galaxy «discoid» and the second a «square» elliptical galaxy. An excellent model of the second type at work noted with the help of the Spitzer Telescope is what is taking place in the cluster of galaxies CL0958+4702, almost five billion light-years from our galaxy, where four large galaxies are joining together to zone a much larger elliptical galaxy surrounded by a great halo made by billions of stars thrown out during the meltdown.
The third way involves a spiral galaxy that has consumed all its gas due to the creation of stars or that has lost it by other methods becoming a lenticular. In this space, the collision and impregnation of minor galaxies, which in the case of a spiral galaxy would have hardly any consequence when remedying the stellar constitution caused in said collisions the damages tolerated by the disk of said galaxy, end up demolishing the disk of the lenticular galaxy, transforming it into an elliptical one.
It is believed that all galaxies huge ellipticals they have a super massive black hole at their axis.
2. Spiral galaxy
This type of galaxies has a nucleus or bulb made by population stars II (old, yellowish-orange, and low metallic content), and a disk with a large amount of interstellar gas and dust, which shows the creation of young, bluish, and very metallic stars (type I population stars), increasing the aforementioned spiral arms, which are created as shock waves due to the differential rotational current of the entire galactic disk. You can find out more about how galaxies are formed at this interesting article.
Essentially, spiral galaxies are classified into two large groups: Normal spirals and barred spirals (with a beam of stars passing through the core).
3. Lenticular Galaxy
What Are The Types Of Galaxies That Exist is a very common question and for this reason I will present another of them, the galaxy lenticular, these have the shape of a core with a disk, but without spiral arms. They are made up of old stars, with little metal, and no interstellar gas or dust. To better understand the difference between these and other types, see the article on lenticular galaxies.
They differ from elliptical galaxies in that they do have a disk, unlike those that only showed a more or less flattened nucleus. And they diversify from spiral galaxies in that the disk is similar, that is, without stellar arms due to the cohesion waves typical of the gear movement of the stars near the galactic core.
Lenticular galaxies tend to be left over in rich galaxy clusters, in extortion from spiral galaxies, and apparently they were once spiral galaxies that wasted their gas by rubbing against the gas heated intergalactic that fills the intergalactic space or by gravitational interactions with other galaxies (the latter supporting starbursts that would contribute to the loss of their celestial environment and the growth of their central bulge). Learn more about dwarf galaxies in the corresponding article, which can be found at dwarf galaxies.
4. Irregular galaxies
An irregular galaxy is a galaxy that does not have any precise shape. They are galaxies without spiral, lenticular or elliptical. Some irregular galaxies are small spiral galaxies warped by the gravity of a very excessive neighbor.
So notice what are the types of galaxies that exist in our wonderful and extensive Milky Way.
