A galaxy is a system of stars, stellar remnants, interstellar gas, and dust. Its name is derived from the Greek word galaxies, which is the name given to the Milky Way galaxy. Galaxy lovers should be aware of the fact that this planet is made of stars and other matter that are in a mutual gravitational attraction. This article will provide some basics on the subject of galaxy and its major classes.
Strangely shaped galaxy
A wide-field image of a strangely-shaped galaxy has been captured by NASA’s Keck Telescope in Hawaii. This galaxy has an infrared bright core and a long tail that extends 130 thousand light years. Its multiple components are not clear to humans, but researchers have already detected them in near-infrared observations. The discovery could point to the existence of active galactic nuclei, which are power by supermassive black holes.
The boomerang-shapes galaxy has been discoveres in a tendril of super-heated gas that connects massive galaxy clusters. These tendrils are call filaments, and they form intricate latticeworks. It is thought that the boomerang-shapes galaxy was swept into shape by gas from a filament in another galaxy. Other similarly bent galaxies could be signposts of these cosmic gas filaments, which could be fertile star-forming regions.
Major classes of galaxies
Astronomers have identified two major classes of galaxies – spirals and irregulars – based on the physical properties of their structures. Both schemes were originally devise by Edwin Hubble and were later refine by Gerard de Vaucouleurs and Allan Sandage. Today, classification of galaxies is largely based on physical morphology and computational methods. In this article, we will examine the characteristics of each major class.
The first classification of galaxies was proposing in 1936 by astronomer Edwin Hubble. His “tuning fork diagram” has continued to be useful for astronomers. Elliptical galaxies are egg-shapes and featureless, with a decreasing surface brightness as one moves outwards from the center. These galaxies typically have a long axis four times longer than its short axis.
Structure of galaxy
In this article, we will discuss the structure of a galaxy. The galaxy consists of two main parts. The galaxy disk contains the stars and the interstellar dust. Star formation occurs mostly within the galaxy disk. This is the reason for the dark streaks you see all over the Milky Way. These streaks are cause by interstellar dust. The structure of a galaxy can be further studied using the spectral line properties.
The universe contains organized structures on all scales, from small systems that contain trillions of stars to large systems that contain billions of galaxies. Modern astrophysics is concerned with the formation and evolution of these structures. Using observations and simulations, astronomers can now understand how large systems influence small ones. The data from COSMOS have allowed astronomers to understand how large and small systems interact with each other. The new study shows that the universe is fill with massive, organize structures that influence the evolution of smaller galaxies.
The supermassive black hole at the center
Almost every galaxy has a supermassive black hole at its center. In recent years, scientists have been focusing on the relationship between the central black hole and the host galaxy. Generally, the galaxy formed first and accreted around the black hole. The relationship between black hole mass and bulge is linear. For example, a galaxy with a black hole at the center will have more mass than one million suns.
Astronomers have identified a black hole in the center of the galaxy Messier 87, which is 6.5 billion times the mass of the sun. This massive black hole spews out material into deep intergalactic space, which is why it is call a supermassive black hole. However, most black holes are not this large. Instead, they are much smaller than our sun.
Origin of galaxy
The Brahma Sutra model of the origin of the universe suggests that the first galaxies in our galaxy arose from an embryonic, high-density pool that exploded into visible matter. The current scientific models assume that the explosion took place when the universe was super-high-density, about the same size as a proton. But the Brahma Sutras are bases on Hindu mythology, so it is unclear if this model can be consider scientific.
The “pizza-dough” model does not account for the observations that show stars outside the disk. SO, the “top-down” formation scenario posits that galaxy formation took place during a time when the universe was much more primitive. TheAstronomers have gathered some evidence for this theory, but they are still searching for additional evidence. Regardless of the theory, the question of the origin of the galaxy remains an enigmatic one.