Life Cycle of a Star - Worksheet

Nebula

A large cloud of gas and dust in space where stars begin their life cycle.

Protostar

The earliest stage of a star’s life, formed from the contracting gas and dust of a nebula.

Nuclear Fusion

The process that occurs when a star becomes hot enough to fuse hydrogen atoms, marking the birth of a star.

Main Sequence Star

A star that has begun nuclear fusion and is in a stable phase of its life cycle.

Red Giant

A stage that occurs when a low or medium mass star runs out of hydrogen fuel and expands.

Red Super Giant

A stage for high mass stars similar to red giants but larger and more luminous.

Planetary Nebula

A cloud of gas formed when the outer parts of a low or medium mass star drift into space after becoming a red giant.

White Dwarf

The hot core left behind after a low or medium mass star has shed its outer layers.

Black Dwarf

The final stage of a white dwarf when it has cooled and no longer emits significant heat or light.

Supernova

The explosive death of a red super giant star, resulting in a massive release of energy and material.

Neutron Star

The dense core that remains after a high mass star undergoes a supernova explosion.

Black Hole

A region in space with a gravitational pull so strong that nothing, not even light, can escape from it, formed from the remnants of the most massive stars.

1. nebula

2. low-medium mass protostar

3. low-medium mass main sequence star

4. red giant

5. planetary nebula

6. white dwarf

7. black dwarf

life cycle of a low-medium mass star

1. nebula

2. high mass protostar

3. high mass main sequence star

4. super red giant

5. supernova

6. a) neutron star b) black hole

life cycle of a high mass star

low-medium mass protostar

B

planetary nebula

E

white dwarf

F

super red giant

D

Supernova

E

Black hole and neutron star

F and G

nebula, protostar, main sequence star

What life cycle stages to both high and low mass stars have in common?