6 Jan 2019

The home of 200 billion stars"The Milky Way"

The milky way 

Milkyway galaxy

The universe is full of surprises and mysteries and humans are curious. This interesting relationship between humans and universe is the reason behind such a huge number of unsolved mysteries.
Today we know that, we are living in a planet named as earth, this planet is in our solar system and this solar system is present at outer edge of our galaxy " the milky way ".

Here the question is, how much we really know about our own galaxy?

Let's try to get answer of the question.

 Facts of milky way

The size of milky way is 100,000 light years, which means light will take 100,000 year to travel from one end of the galaxy to another end.
Milky way is the home of more than 200 billion stars.

Until 1920s astronomers thought, all the stars and everything is inside milky way galaxy. Our milky way is considered in a spiral galaxy.

The study of galaxy helps in understanding, how our universe and their stars forms.

The place where stars born in called nebula. It is a complex mixture cloud of gasses and clouds which emits light. Our galaxy also contains many of nebulas where stars born’s.

Most interesting facts of milky way:-

 1. All naked-eye stars contained in milky way :- it isn't that long ago that we use to think of the stars as light leak in a black curtain, just a little further than we could reach, and heaven was on the other side. 
In actual fact, all the stars that we can see in the night sky with the naked eye, which is around 9,096 or 4,548 from each hemisphere, are contained within our own galaxy.

 2. Milky way is classified as barred spiral galaxy:- the milky way is a spiral armed galaxy, and as is typical for about 67% of those, ours is barred. It is suspected that such bars are the consequences of a galaxy drawing gas from its spirals into its heart, but as the density of the bars increase over the millennia their own gravity destroys them resulting in spirals without bars.

 3. A black hole is located at its centre:- after such a long discussion and debate in scientific world now we can say that, a super massive black hole is present at the centre of milky way. That black hole is named as Sagittarius A and it is situated at 26,000 light years from us and it's weight is equal to 4.1 million solar mass which is a source of intense radio waves.

Nebula in milky way

Nebula in milkyway galaxy

Study of nebula in a particular galaxy is the best way to understand that galaxy.
When lots of gasses and dust collected a place in a galaxy then that could make the light of stars dim. With the observation by the Hubble telescope, now we also know that the nebula doesn't only make star's light but the clouds of nebula also Emit light. The colours in a nebula also tells about the elements by which the nebula formed.

Orion nebula:- It is situated at 14 light years from us. It is a shining cloud of gasses and dust. With the help of this nebula, we could know that how our Sun or any other star originated. Study tells that, some stars in Orion nebula is to much new some of them are lakh year old only. It is one of the brightest nebula and visible to the naked eye in night sky. It is also known as messier 42/ m42/ NGC 1976. The nebula is part of a much larger nebula that is known as the Orion molecular cloud.

Formation of stars

Formation of star

Observation of the nebula have revealed approximately 700 stars in various stages of formation within the nebula. Stars form when clumps of hydrogen and other gasses in an H|| region contract under their own gravity. As the gas collapses, the central clumps becomes stronger and the gas heats to extreme temperatures by converting gravitational potential energy to thermal energy.

If the temperature gets high enough, nuclear fusion will ignite and form a protostar. The protostar will born when it begins to emit enough radiative energy to balance out its gravity and halt gravitational collapse.

Star formation is the process by which dense regions within molecular cloud in interstellar space sometimes referred to as "Steller nurseries" or "star-forming regions", collapse and form stars.

As a branch of astronomy, star formation includes the study of the interstellar medium and giant molecular clouds as precursors to the star formation process, and the study of protostars and young Steller objects as its immediate products. It is closely related to, planet formation, another branch of astronomy.

Star formation theory as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function. Most stars do not form in isolation but as part of a group of stars refers as star clusters or Steller association.

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