The Mikly Way Galaxy is home to our solar system. It includes thousands of clusters of stars and nebulae. The galaxy can be seen as a faint band of hazy white light in the night sky. It has a diameter of about 100000 light years and is very massive.

The Milky Way is a spiral galaxy and has about 200 billion stars. It has six spiral arms, four elliptical bulge. The arms twirl out from the nucleus like a giant wheel. All objects in the galaxy orbit around a common centre of mass. This centre of mass is called the galactic centre.






Age of the Milky Way: 

The Milky Way is one of the oldest galaxies. Scientist believe that it is around 13.6 billion years old. They have calculated the age of the Milky Way by measuring the difference in the beryllium content of an adolescent star and that of a nearly dead one. The two stars that were studied are A0228 and A2111 innthe globular cluster NGC 6397.






Virgo supercluster: 

The Milky Way is located in the Virgo Supercluster. The Virgo Supercluster has a diameter of around 200 million light years. It contain several local groups and smaller cluster. The most dominant cluster in the supercluster is the Virgo Cluster.





Types of Stars:

The Milky Way has two types of stars: type I stars and type II stars. The type I stars are brilliant, blue star and the type II stars are giant red stars. The type II stars from the halo of the galaxy. The central region of the galaxy  has stars of both type I and type II.



Greek mythology and the Milky Way: 

Our galaxy gets name from Greek mythology. According to one account , Hera, Zeus' queen, was tricked by Zeus to feed his son . When she came to know about this , she spilled the milk in the sky. The spilt milk became the Milky Way Galaxy.

Local group: 

The Milky Way is a member of the Local Group of galaxies. The group was first recognized by the Hubble space telescope. There are over 30 members in the local Group. It has a diameter of about 10 million light-years. The Large and the Small Magellanic Cloud along with several smaller galaxies are members of the Local Group. The Milky Way and the Andromeda Galaxy are the most massive and dominant members of the group. The gravitational centre of the group is located at some point between the Milky Way and the Andromeda Galaxy. 







Dwarf galaxies of the Milky Way:

The Milky Way has many dwarf galaxies nearby. These are Draco, Carina, Sextans, Sculptor Fornax,Leo I, and Leo II.






Arms of the Milky Way:

The major arms of the Milky Way Galaxy are the Perseus Arm, Sagittarius Arm, Centaurus Arm, and Cygnus Arm. Our solar system is in a minor arm called the orion Spur. The arms are named after the constellations seen in their direction.