Life Cycle of a Star Quiz

Life Cycle of a Star

• Stars begin as protostars, which are huge clouds of hydrogen gas.
• Protostars form when these clouds collapse.
• Protostars are thousands of times larger than our solar system.
• The collapse of these clouds causes stars to be born.

Main Sequence Star

• Our sun is an example of a main sequence star.
• Main sequence stars fuse hydrogen into helium.
• The main sequence phase lasts billions of years.
• Our sun has been a main sequence star for about half of its lifetime.

Red Giant

• When a star runs out of hydrogen, it expands and cools.
• The outer layers of the star expand massively.
• The star becomes a red giant.
• Planets like Earth, Mercury, and Venus are at risk of being swallowed up by their respective red giant sun.

White Dwarf

• Gravity causes the red giant to collapse into a white dwarf.
• The white dwarf is much cooler compared to the former main sequence star.
• It has the same mass but is significantly smaller than the original star.
• It is composed of degenerate matter (helium, carbon).

Black Dwarf

• The white dwarf cools more, eventually becoming a black dwarf.
• This is the final stage of a star like our sun.
• A black dwarf emits no more light.

Massive Star (Red Supergiant)

• Stars significantly larger than our sun will become massive red supergiants.
• These stars fuse multiple elements in their cores, causing them to become increasingly massive and large in size.

Supernova

• A supernova is when a red supergiant explodes.
• This explosion is the largest in the universe.
• Supernova explosions are extremely powerful, blasting matter and energy throughout space.
• The material from these explosions are recycled throughout the universe and form new stars and planets.

Black Hole

• After being a supernova, remaining materials from massive stars can form a black hole.
• The gravity is immense, not even light can escape it.
• Black holes can absorb surrounding matter.
• Black holes can cause neighboring stars and planets to be absorbed.