Can cloud form a star?

     The answer is yes.  Cloud can from a star.  

     We can see so many stars in the sky at night.  We know that stars are huge fire balls and it has high amount of heat and light.  But, we may not know how it forms?

   

     Stars are formed by the clouds called nebulae or black nebulae(this cloud consist of dust and gas), which present in the space.  It consist of Hydrogen(H) and Helium(He) molecules and some other particles and it is cold.  Whenever the supernova explosion(it happens at end of the star cycle) takes place, it makes shock waves and it releases huge amount of energy, towards cloud.

(What is gravity?  An invisible force that pulls objects towards each other.  Every object in space having its own gravity.)

     This cloud having its own gravity.  Due to the huge amount of energy, the cloud get gravitational disturbance.  And it begins to collapse on itself.  It causes H and He molecules to gather in the mid of a cloud.  It increase the mass in the mid of the cloud due to this, and also increases gravitational pull.  This force(gravitational pull) attracts more molecules and particles from the surrounding.

     At one point, the mid of a cloud become a shinning ball called proto star.  There, nuclear fusion happens.  Due to that reaction, it get more heat, light and radiation.  So, a star forms.

     You may ask one question? Due to gravitational pull, that star may get smaller and smaller.  But it didn't, how?

     Yes, it is a good question.  Gravitational pull creates inwards force.  Heat and radiation create outward force.  So, it get balance.