HOW THE MILKY WAY GALAXY FORMED .......

HOW THE MILKY WAY GALAXY FORMED ....... 

 

The galaxy and stars are formed in the observable universe. They were hundred of billions of galaxy, each will many million or billions of individual stars. 

It's a pretty typical barred spiral galaxy containing.Some where between 200 billions and 400 billions stars. It is about 100,000 light year in diameter, meaning it take light 100,000 years to travel 100,000 from one end to other, where as it is only about one thousand light are thick there were are estimated as there are no well defined edges to the galaxy. It is a simply a disk with several arms of varying sizes, surrounding by a halo of stars , with a dense in the middle, most like  a  super massive black hole at the center of it's nuclear. just like other large galaxies . About Fifteen percentage of the visible mass of the milky Way is in the form of interstellar  gas and dust, scatted between all the stars. Some of these stars form grouping call open cluster   , such as the pleiades , which is a few hundreds stars bound family close together beyond the stars in the disk, there are also reversal object is more distance orbits called globular clusters . These are dencer, spherical collection of stars, any where form a few hundreds  thousand to a few million and these are a little more than 150 of them travelling around the halo they were always filled with population two stars, indicating that they are very old, probably forming at the  same time as the milky way. 

The milky Way also had some satellite galaxies. Which are smallest galaxies the orbit around it. The most prominent of these are the small magellanic cloud  and large magellanic cloud each around tenth the size of milky Way an observable form the southen hemisphere. There interact with the milky Way as they orbits, resulting in disturbances and also exchange of material. Andromeda and milky Way are also on paths that will cause them to collider some time around four billion years form now. Simulation show that will be an incredible even that will take several billions years to play out to completion. Many stars will ejected but the end results will likely be a merging to form a large more elliptical galaxy that has been dubbed  Milkdromeda .

A  look at the observable universe there are many million if billions of galaxy these are called as virgo supercluster, containing over a hundred smallest groups and cluster of galaxy, such as the virgo cluster and the local groups. See the local group contains more than fifty galaxies, many of which are tiny dwarf galaxies but some of which are fairly large by galactic standard. The largest of these us called the andrimeda galaxy, which is spiral galaxy around half that size. The next biggest is called milky Way galaxy also a spiral galaxy that's our galaxy

 

Will it rotation provides some information stars out side of  move around galactic center with a speed of around 220 km/sec. That's astonishingly fast by earthly standards but even so, it taken stars in the outer areas about 250 million years to go once around. The closed stars are to the center, the less time they to orbit just like planets are around this sun . This is phenomenon  that is largely responsible for the formation of the spiral galaxies as well can ovserve by looking at other galaxies in our vicinity. The oldest star we can see in the milky Way are very old population of two stars. So we belive that the formation of milky way dates back to the early eras of galaxy formation, less than one billion years after the BIG BANG. The dense region of gas collected to form a system.. 

gravitationally bound stars. Due to the centre fugal force and accentued by conservative of a angular movementum. This began to spin in the way it does now collapasing form a sphere into a disk and has presumably been undisturbed by a major collection all these billion of years, as it's spiral shape has been retained. The older population two stars can be found in the halo, from the time of the galaxy's formation where as most stars in the disk are younger more likely, to be population one  stars formed after the galaxy had already begen a to taken it's current shape. An estimated three to five stars per year continue to from today, from all the interstellar gas and dust. Eventually all the stars that can form from the gas and dust will have formed and many will die, predicting a grim, dark fate for the galaxy in some several hundred billion years. But these is must more to talk about regarding the past and  present first. Some time into the existence of the milky Way, a little less than five dillion years ago, a cloud of gas and dust, full of heavy elements dispersed from the death of population three and two stars, began to accrete to from q very families set objects, our over solar system.