The Milky Way

The Milky Way,
I have always been interested in Astronomy, the study of our universe: the constellations, the nebulae and the galaxies. I found it very fascinating.
Of course one has to start from studying our solar system that belongs to The Milky Way galaxy.

The Milky Way is the galaxy which is the home of our Solar System together with at least 200 billion other stars, and thousands of clusters and nebulae. All the objects in the Milky Way Galaxy orbit their common centre of mass, called the Galactic Centre. As a galaxy, the Milky Way is actually a giant mass of probably between 750 billion and one trillion solar masses. Its diameter is about 100,000 light years across and the thickness is 1000 light years. The age of the Milky Way was estimated to be around 14 billion years, and our Solar System is 4 billion years old.
The Milky Way Galaxy belongs to the Local Group, which consists of 3 large galaxies and over 30 smaller galaxies. The 3 large galaxies in the Local group are the Andromeda Galaxy M31, The Milky Way and the Triangulum spiral M33.

Like early explorers mapping the continents of our globe, the astronomers are busy charting the spiral structure of our Milky Way galaxy.
Using infrared images, scientists have discovered that the Milky Way's elegant spiral structure is dominated by two arms wrapping off the ends of a central bar of stars, as shown on the accompanying artist's diagram (with "Star Wars" music theme).
The spiral arms of our Milky Way contain interstellar matter, diffuse nebulae, and young stars and open star clusters emerging from this matter.
On the other hand, the bulge component consists of old stars and contains the globular star clusters. Our galaxy has probably about 200 globulars, of which we know about 150. These globular clusters are strongly concentrated toward the Galactic Center.

Our Solar System consists of 9 planets lies near a small partial arm called the Orion Arm, located between the Sagittarius and Perseus arms of The Milky Way.
The inner solar system contains the Sun, Mercury, Venus, Earth and Mars. The outer solar system are Jupiter, Saturn, Uranus and Neptune. ( Pluto, used to be called the 10th planet of the Solar System is now classified as a dwarf planet).