Andromeda Galaxy

    

Andromeda galaxy is twice bigger than our galaxy , which is 220,000  light years in diameter. It has more than 1 trillion stars, which is also twice the number of stars in our very own milky way galaxy. The distance between our galaxy and Andromeda galaxy is about 2.5 million light years. It is approaching to our galaxy at the speed of 120 km/s  which collides with our galaxy. 

   Oh oh wait..... 

            It's not going to happen that much earlier, but you have to  wait for estimated time of 4.5 billion  years. We'll see about galaxies...Every galaxies can have a huge spherical halo around it.

                

                 
       Galaxies  have two hallos- inner and outer hallos.Those were nothing but envelope of gas covering entire galaxies. In the case of Andromeda,it have a huge halo of about 2 million light years.Now recent research shows that the halo's of Milky way and Andromeda galaxy start colliding with each other.

         When two galaxies start to collide,this will happens. First of all,they both combine and form a new galaxy. Many large galaxies can attract a smaller ones. The gravity of larger galaxy pulls the smaller one. However,the galaxies are made up of stars,dusts,rocks,gas etc.when galaxy collides,gasses in galaxies form a very huge cloud of gases all around the galaxy.Then the gasses starts to become more denser and experience more pressure. The combination of these gasses can cause a new stars to born. Already existing stars probably move to  some million or billion light years away from current position.

     

    Every galaxy can have a very own supermassive black hole.  Scientists think that both black holes will combine during the collision,but they don't know what the results  will be(but they are not going to be good).

    

       Note:- Don't imagine like two planets colliding with each other, forming a big explosions and pieces of planets all over the galaxy. It is not the way it's going to happens. When they collide they give birth to new stars and some newly born stars some not able to survive and some will make it.

   What is one  light year?

              One  Light years is the distance travelled by the light in one year. Which means, the speed of light in vaccum is 299,792 km/s. One light year is approximately 10 trillion kms.

  Take a deep breath....there are 200 billion galaxies in the observable universe. Imagine that ,by the time you are reading this somewhere, somehow two or more galaxies colliding with each other and forming newer ones.