In our childhood, we all have seen different pictures of galaxies and also used to think about it. But we can not have a proper idea or actual knowledge about it and its history of making as well. There are roughly 200 billion galaxies in this Universe.
Galaxies are sprawling gravitationally bound space systems composed of dust, gas, dark matter, and countless stars. Most astronomers believe that 10 billion to 20 billion years ago shortly after the cosmic “big bang” the galaxies were formed. Galaxies may be Active and Normal or Dormant. Active galaxies release far more energy than the normal galaxy. Galaxies can vary in shape and size. In the universe, especially spiral, elliptical or irregular shaped galaxies can be found. Most galaxies contain a black hole in its center. Our Earth is the part of the galaxy known as the Milky Way. Spiral galaxies consist of planets, stars, gas and dust. Elliptical galaxies consist of a large number of older stars, interstellar matter, and very little dust. There are different opinions about the formation of such galaxies. Because the theory of Scientists and astronomers differ in the way of their thinking.
Here are some of the notable largest galaxies discussed bellow.
This galaxy is also known as NGC 224 or Messier 31. this galaxy was named after Andromeda, the mythological princess. It is also considered as the closest galaxy to Milky Way.
This galaxy has a spiral shape, and it is 2.5 million light years from our planet. It is the collection of multiple smaller galaxies and it contains approximately 1 trillion stars in it. The estimated mass of this Galaxy is 1.5 × 1012 solar masses. This galaxy was formed at large 10 billion years ago.
11. ESO 306-17
The ESO 306-17 is a giant elliptical galaxy of the fossil group. It is 493 million light-years away from the Earth. This galaxy belongs to one of the largest galaxies in the Universe.
10. NGC 6872
The NGC 6872 is a large barred spiral galaxy also known as the Condor Galaxy. It is located 212 million light-years away from the Earth. The English astronomer John Herschel discovered the galaxy in 1835.
The five billion years old galaxy has two elongated arms. The diameter of the galaxy is around 522,000 light-years. It has an interaction with the galaxy named IC 4970.
9. Malin 1
The Malin 1 is situated 1.19 billion light-years away from the Earth. It is a spiral galaxy with a low surface brightness (LSB). Astronomer David Malin discovered the galaxy in 1986.
The diameter of the galaxy is approximately 650,000 light-years, and it is the first LSD galaxy so far discovered. The most interesting thing is the galaxy is increasing day by day by eating small galaxies or merging with the smaller ones. Malin 1 has another special feature like it has a straight pointer from it such as an 11 O’ clock position. Probably it is all about the presence of a long stream of gas.
8. Comet Galaxy
The Comet Galaxy is situated in the galaxy cluster Abell 2667 and 3.2 billion light-years away from Earth. It was detected by Hubble Space Telescope in 2007.
The Comet galaxy has a tail of around 600,000 light years long.
7. UGC 2885
The UGC 2885 is a jumbo spiral galaxy. It is around 310 million light-years away from earth with a relatively low surface brightness.
It is one of the largest spiral galaxies with the diameter of about 832,000 light years. The most prominent feature of the galaxy is its central giant nucleus.
The A2261-BCG has located approximately 3 billion light-years away from Earth. It is elliptical in shape and was found by Hubble Space Telescope.
A2261-BCG has a diameter of a million light-years and a galactic core spanning over 10,000 light-years. The core of this galaxy is highly populated by a large collection of old stars. There is no supermassive black hole in its center.
5. NGC 4874
The NGC 4874 also known as Coma A was discovered in 1785 by the British astronomer Frederick William Herschel I. It is 350 million light-years far from the Earth.
It is a smooth, ball-shaped galaxy surrounded by a stellar halo which is about one million light-years in diameter. In its core, a supermassive black hole is there. A highly energetic plasma jet is stretched out to 1,700 light-years from its center. The NGC 4874 is a collection of about 300 galaxies.
4. NGC 4889
The NGC 4889 is also famous as Coma B, a supergiant elliptical galaxy situated approximately 308 million light-years away from the Earth. British astronomer Frederick William Herschel I discovered this galaxy in 1785.
The diameter of the galaxy is 239,000 light years with an effective radius of 326 million light years. It holds a massive black hole in its center. The diameter of the black hole is about 20 to 124 billion kilometers. The NGC 4889 is the collection of multiple smaller galaxies and it contains approximately 10,000 or more galaxies. It emits ultraviolet, soft X-ray, and radio frequency radiation.
3. NGC 262
The NGC 262 is located at 202 million light-years away from the Earth which is one of the largest spiral galaxies known. Lewis A. Swift was discovered the NGC 262 in 1885.
The diameter of the galaxy is approximately 1.3 million light-years. The NGC 262 is surrounded by a gigantic neutral hydrogen gas cloud which has an approximately 50 billion solar masses. It is made up of approximately 15 trillion stars.
2. Phoenix Cluster
The Phoenix Cluster is one of the most massive galaxy clusters in the universe. It is located approximately 5.7 billion light-years away from the Earth.
The elliptical galaxy is composed of intra-cluster medium and dark matter. The galaxy extends to more than 1.1 million light years from the center which is associated with a supermassive black hole. It is a huge collection of about 1,000 galaxies. The Phoenix Cluster galaxy contains a large amount of hot gas and it was detected by the South Pole Telescope, applying the Sunyaev – Zeldovich effect.
1. IC 1101
The IC 1101 is the largest galaxy of the universe. The galaxy is elliptical to lenticular in shape and appears as golden yellow color. The brightest galaxy is situated more than 1.04 billion light-years away from the Earth.
The British astronomer Frederick William Herschel I first discovered this galaxy in 1970. The IC 1101 has the effective radius of 210 ± 39 thousand light years and populated by 100 trillion metal-rich stars. It consists of a large black hole in its center.
Looking up at the stars in a dark night can help to take a look at and feel the utmost beauty of the natural view. Galaxy is considered as an open source. Galaxy is held together by gravity. Galaxies differ from each other due to various reasons. In the basis of brightness, area, mass, colors and location it can differ. There is no fixed statistics in this field. This will continue to get enlarged on the basis of observations and inventions. The most simple technique is to determine the distance is to measure its velocity. But this distance is uncertain because of its random motion.