Comets

Comets are small and have a composition of ice, rock, and cosmic dust loosely packed together. Comets come from the cold, outer solar system. When a comet passes close enough to the sun, solar radiation heats the water ice so that the comet gives off gas and dust in the form of a long tail. This is how a comet gets its tail. Sometimes a comet can get two tails, an Ion tail or a dust tail. The ion tail is made up of electrically charged particles called ions. The solid center of the comet is called the nuclei. A comet's nuclei can range from less that a half a kilometer to more than 100 kilometers in diameter

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The big bang theory

Big Bang Theory 

The Big Bang theory is an effort to explain what happened at the very beginning of our universe. Discoveries in astronomy and physics have shown beyond a reasonable doubt that our universe did in fact have a beginning. Prior to that moment there was nothing; during and after that moment there was something: our universe. The big bang theory is an effort to explain what happened during and after that moment. 

According to the standard theory, our universe sprang into existence as "singularity" around 13.7 billion years ago. What is a "singularity" and where does it come from? Well, to be honest, we don't know for sure. Singularities are zones which defy our current understanding of physics. They are thought to exist at the core of "black holes." Black holes are areas of intense gravitational pressure. The pressure is thought to be so intense that finite matter is actually squished into infinite density (a mathematical concept which truly boggles the mind). These zones of infinite density are called "singularities." Our universe is thought to have begun as an infinitesimally small, infinitely hot, infinitely dense, something - a singularity. Where did it come from? We don't know. Why did it appear? We don't know. 

After its initial appearance, it apparently inflated (the "Big Bang"), expanded and cooled, going from very, very small and very, very hot, to the size and temperature of our current universe. It continues to expand and cool to this day and we are inside of it: incredible creatures living on a unique planet, circling a beautiful star clustered together with several hundred billion other stars in a galaxy soaring through the cosmos, all of which is inside of an expanding universe that began as an infinitesimal singularity which appeared out of nowhere for reasons unknown. This is the Big Bang theory.

How universe was formed

Does  any  one  believe  that  a small  accident  in space  creates  our  universe 

that  small  accident  was  big bang

About a half a million years after the big bang, the cosmos began to cool, as it cooled, the hot subatomic particles that constituted the early universe began to slow down and stop colliding with each other long enough so that protons, neutrons and electrons could form. The universe cooled further and the hot particles slowed further still allowing these particles to stay together long enough to create atoms.

The universe was nothing but a cloud of hydrogen and helium. Slowly, the universe continued to cool and structure begins to present itself within this universal cloud. From small disturbances woven into spacetime the galaxies begin to collect, tiny variations in the primordial universe became the web that collected galaxies and gave the cosmos its form.

hydrogen  gas come   to  one small place  its  the  formation of universe

These galaxies become distributed along these structures, dancing within their gravitational fields, forming giant tendrils reaching out across the span of eternity.

Until just a few short decades ago, astronomers thought the universe was static and unchanging, we didn't even know there were other galaxies until the 20th century. The heavens was a place of constancy and uniformity, the stars and planets were always there and they always would be - steady and unchanging. Instead we have learned that the cosmos is a seething cauldron of activity, as alive and vibrant as any one of us.

Stars are born, shine and explode; stellar winds blow huge storms of gas across interstellar space; black holes devour all they touch; galaxies collide with each other, spraying stars into eternity.

And spacetime itself grows larger by the minute.

The universe is far from a static place. As giant stars explode after living out their lives, they stream out the elements of life, carbon, oxygen, nitrogen, iron, all the necessary components for planets to form and for life to begin. We are more connected to the universe than we know, the stars are our ascendants (forefathers), we are their progeny.



today  i was shocked  
today  i was watching  a  science fiction 
after  big bang in space 
big bang  is a great explosion after that  its  expands  
in the  expansion  our  solar system is  one of  them    
interesting  thing  if we  compress  crush   a hydrogen  gas in  one place  it with  turn  in to small  fire ball if  we add more gas  and  it turns  big with  gasses 
slowly  it become  food ball shape  it  creates  inside  iron ,gold , all minerals  if it grow  bigger  and  bigger  its  sun  if  it grow more bigger  its   star 


if stars are cool it with ice  and it turns to planets