4. About Outer Space

    I will introduce the outside of the solar system now. What we can observe is a small part of the whole universe. It is not less than ten percent of the whole universe.

    Earth  belong to the solar system. There are many other organizations such as the solar system in universe. they are gathered and form a giant spiral or disk. This is the galaxy. We can observe from inside the galaxy which we belong. It is a so-called Milky Way. Plenty galaxies are also gathered, forming a cluster of galaxies. They are also gathered, they will form a supercluster. On the whole observable universe, celestial bodies are distributed in the form, such as a foam. But distance that we can observe is in the range of 93 billion light-years in diameter approximately. Because IDM distant is expanding faster than the speed of light. It is that to so, where light does not reach is invisible for us.  
    

Big two are Rigel and Aldebaran, other are Bellatrix, Algol B, Sun.

    There are a variety of celestial objects in the universe. Planets and satellites, and the like star. Human grow older. Star also grow older. Protostar glow in the only potential energy. This is a baby star. Main-sequence stars glow by the nuclear fusion. Sun is also included in this. Star most of the universe is a main-sequence stars. Star that is being run out of nuclear fusion energy becomes red giant. Star has a wide variety of end. Small star just go cold and dark. Huge star cause supernova explosion. Neutron star remain after, or stars that are too large become a black hole. When a star dies, it will release the material of the next star. We observed it as a nebula. Stars are born or dies somewhere at any time in the universe. 
    

If we see the Black hole, it become like this.

    Celestial objects with various properties exist in the universe. Neutron star is a celestial body of small and rotates at high speed. Sometimes energy it emits will be regular as a pulse signal. In that case, We call the pulsar neutron star. Neutron star with a strong magnetic field is called a magnetar neutron star. These stars also known that the density is high. It is said that its density is also one hundred trillion times that of the sun. When the star is no longer withstand the mighty gravity of their own, black hole is born. This star has the location and density gravity is infinite. Be stuck even light is also tied to the gravity of this star. So we can not see this star. 

    By the way, look at the night sky, we can say that star is bright. In most cases, they are close to the Earth relatively. I want to see the stars are in far away.


The sources: 
http://en.wikipedia.org/wiki/Universe
http://4d2u.nao.ac.jp/html/program/mitaka/index.html
The pictures:
http://upload.wikimedia.org/wikipedia/commons/1/11/1e10m_comparison_Rigel%2C_Aldebaran%2C_and_smaller_-_antialiased_no_transparency.pnghttp://www.spacetimetravel.org/galerie/sl218.jpg
http://www.youtube.com/watch?v=MzVduP6ud9Y