Did you know it takes 240 million years for our sun to complete a revolution around the Milky Way’s center? For those of you who don’t spend much time studying our space and universe, the Milky Way Galaxy is home to our solar system, which is home to planet Earth. At first, Greek philosophers and astronomers estimated that the Milky Way Galaxy, which appeared to be a glowing cloud of gas and dust, was a part of the earth’s troposphere. It was only after Galileo, the famous Greek astronomer, observed this cloud of intergalactic debris through his homemade telescope and found this globular cluster of dust to house millions of stars and other heavenly bodies, that he discovered the true Milky Way Galaxy. The Milky Way Galaxy was named because of its appearance from Earth as a dusty ring of hazy lights. The galaxy could be seen in the night sky and comprised an innumerable number of stars that could not be distinguished without a telescope. The Greek translation of the word Milky Way literally means ‘milky circle’ as the structure of this enormous galaxy appears like a stellar disk when viewed from the surface of the earth. This band of light was first discovered in the year 1610 by the famous Greek astronomer Galileo who simplified the structure of a hazy cloud as a cluster of an uncountable number of stars mixed with other intergalactic debris. The astronomers of the 19th century believed that the Milky Way was, in fact, the only galaxy present in the universe and housed all the stars and other heavenly bodies that could be seen from the surface of the earth. But, this claim was falsified by the discoveries of Edwin Hubble in the 1920s. His studies showed that the Milky Way Galaxy was actually just one of the numerous galaxies present in the universe.This spiral galaxy is estimated to have a diameter of approximately 100,000 to 200,000 light-years. For better clarity, a light-year is a distance traveled by light in one year. This means that one light-year is equal to 9.46 trillion km meaning that the length of our Milky Way Galaxy is a whopping 18,920,000,000,000,000,000 km. However, some recent discoveries have led scientists to believe that the Milky Way Galaxy could actually extend up to two million light-years. This conclusion was drawn after recent simulations, where its dark matter, along with some stars, was visible to the astronomers. On top of this, the Milky Way Galaxy also has several satellite galaxies, also known as dwarf galaxies which form the Virgo Supercluster and the Laniakea Supercluster. The Milky Way Galaxy is estimated to comprise over 400 billion stars and the same number of planets. Our solar system has an estimated distance of 27,000 light-years from the center of the spiral galaxy (galactic center), in the galactic north, in the Orion arm, which is a spiral-shaped amalgamation of gases and dust. The galactic center is known to be a supermassive black hole that forms the center of our galaxy with a mass of four million suns. Is there a black hole at the center of the Milky Way? Can an infrared image help see the oldest stars, or are radio waves a better way to identify small galaxies? Is Planet X really a hypothetical planet? Read on to know more about the brightest feature in the spiral structure of the Milky Way visible in infrared light.Different Galaxies In The UniverseA galaxy is a system of stars, gases, intergalactic dust, and debris along with planets, asteroids, and most importantly, dark matter, which is held together by the gravitational pulls of all the above-mentioned objects. These galaxies vary in size, ranging from a few hundred million stars to more than a hundred trillion stars, all of their orbits around the galactic center of the galaxy. Galaxies come in all matter of sizes and shapes, which may be spiral, elliptical, or irregular. Most galaxies are estimated to have a supermassive black hole at their center on which the entire mass of the galaxy revolves. For us in the Milky Way, the Sagittarius-A is the black hole around which all the halo objects of the Milky Way revolve. The star count was estimated to be more than the grains of sand on the earth’s surface. Subsequent space observations have led to the discovery that these galaxies are organized in various groups and clusters that vary in size. For example, the Milky Way Galaxy is a subsidiary of a local group dominated by the Andromeda Galaxy. This local group is located in the Virgo supercluster.The Milky Way Galaxy, the Large Magellanic Cloud, the Small Magellanic Cloud, and the Andromeda Galaxy are a few prominently known galaxies of the observable universe. The GN-z11 is the oldest and farthest galaxy to be observed as of March 2016, which is just 400 million years younger than what is known as The Big Bang.The Structure Of The Milky Way GalaxyWith the commencement of The Big Bang, like every other galaxy, the Milky Way Galaxy started as a mass of clouds made of dust and gases and intergalactic matter. As matter moved away from the center of The Big Bang, the Milky Way gained matter from its neighboring galaxies and took its shape. This matter is what we today know as the halo or the hazy clouds that are observed as an indistinct part of the Milky Way Galaxy. Due to its enormous weight and the conservation of angular momentum, what began as a hazy cloud has taken the shape of a disc-like structure. In subsequent years, the Milky Way Galaxy witnessed the formation of millions of stars, with the oldest ones forming approximately one billion years after The Big Bang. The structure of the Milky Way Galaxy is essentially made of three components, the central disk, which comprises the spiral arms, the halo or the hazy clouds, and the nucleus, which is also known as the central bulge. These components blend into each other, forming the Milky Way Galaxy.The Importance Of The Milky Way GalaxyOther than being home to our solar system and an essential part of the entire existence of the human race, the Milky Way Galaxy has also proved to have a ton of other benefits for us. Its observations have helped us to understand in detail the working of the universe. The Milky Way has proved to be the foundation of all intergalactic and space exploration in modern-day astronomy. Due to its proximity to Earth, it’s much easier for astronomers to observe various phenomena taking place in the universe through the Milky Way Galaxy when compared to other galaxies. Our galaxy has helped scientists to resolve various befuddling questions regarding space and the very formation and essence of the universe. It helps us draw a structure of galactic space in which heavenly bodies exist.The region in which our solar system exists in the Milky Way is a spherical structure that surrounds the galactic disc. This region comprises dark and visible/luminous matter, with dark matter occupying 90% of the total area of the galaxy. These properties of dark matter are studied by astronomers by their effect on the movement of different solar systems and other bodies. All of this together forms the halo of the Milky Way Galaxy. With the passing of billions of years, our galaxy has witnessed the formation and destruction of millions of stars which could still be observed by the astronomers on earth. These observations have helped in developing an understanding of how Earth and other planets were formed over time.The Discovery And Formation Of The Milky WayAs already discussed, the Milky Way was first observed by the ancient Greek philosopher Galileo, who observed it through his telescope in 1610. Prior to this, the galaxy appeared in the night sky as a hazy cloud and subsequent part of the troposphere of Earth and found its mention in Greek mythology. With the help of his self-made telescope, Galileo was able to observe countless individual stars.The Milky Way Galaxy separated itself from other masses of clouds after The Big Bang. With the cooling of the universe, our galaxy witnessed star formation as dust and gases spread uniformly throughout the vicinity of space. With the development of stars, these bodies attracted floating space debris, which further led to the formation of planets that started revolving around their respective stars.According to an estimate, the Milky Way Galaxy produces around seven stars per year, which proves that not all the stars have existed since the primordial universe. Some even call the Milky Way Galaxy a cannibal as we find that the galaxy has swallowed several smaller galaxies in order to gain stellar mass and reach its present size.
Did you know it takes 240 million years for our sun to complete a revolution around the Milky Way’s center?
