gr.8 stars

A .................... is a large cloud of gas and dust containing an immense volume of material.

A contracting cloud of gas and dust with enough mass to form a star is called a ........................

........................... is the process by which atoms combine to form heavier atoms.

When a star begins to run out of fuel, its core shrinks and its outer portion expands.it is called.........................

As the stars start to run out of fuel, their outer layers expand, and they become red giants. Eventually, the outer parts grow larger still and drift out into space, forming a glowing cloud of gas called a .........................

When a supergiant runs out of fuel, it explodes suddenly. Within hours, the star blazes ( burning fire) millions of times brighter. The explosion is called a ..........................

A ....................... may contain as much as three times the mass of the sun but be only about 25 kilometers in diameter—the size of a city.

The coolest stars—with a surface temperature of less than 3,500 K—appear ...............

A .............................is the distance that light travels in one year, or about 9.46 trillion kilometers