Anatomy of the universe-2-(galaxies)

   The universe 

 1- anatomy of the universe speak 

2- galaxies

3- The Milky Way

4-  Nebule and star clusters

5- Stars of northern skies

6-  Stars of southern skies

7- Stars 

8-Small stars

9- Massive stars

10- Neutrons  stars and Black Holes

11- The solar system

12- The sun

13- Mercury 

14-Venus

15-The earth

16-The moon

17- Mars

18 - Jupiter

19-Saturn

20- Uranus

21- Neptune and Pluto

22- Asteroids, comets, and meteoroids 

                                                                                                           2- galaxies

A Galaxy is s a huge mass of stars ,nebulae,and interstellar material .the smallest galaxies contain about 100,000 stars whyile the largest contain up to 3,000 billion stars. there are 3 main types of Galaxy, classified according to their shape: elliptical which are Oval shaped; spiral, which have   arms spiralling outwards  from a central bulget(hose whose arms spiraling outwards from a bar shaped bulge are called spirals) and irregular, which have no obvious shape.

 

 sometimes the shape of a Galaxy is destroyed by collision with another Galaxy quasars (quasii-stellar objects) are thought to be galactic nuclei but are so far away that their exact nature is still uncertain. they are compact, highly luminous objects in the outer reachs of known universe: while the furthest known “ordinary’’ galaxies are about 12billion light years away, the furthest known quasar is about 13 billion light years away.

 

 active galaxies, such as seyfert galaxies and radio galaxies, emit intense radiation. In a seyfert Galaxy, this radiation comes from the galactic nucleus; in a radio Galaxy, it also comes from huge lobes on either side of the Galaxy. the radiation from active galaxies and quasars is thought to be caused by material falling into central black holes.

 


 

 

 3- The Milky Way.....coming soon

 

 

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