What are the cold, dark clouds of hydrogen gas and dust where stars begin to form called?

• Galaxies

• Quasars

• Nebulae

• Supernovas

What two forces are typically in balance within a gas and dust cloud before star formation is triggered?

• Magnetic force and electric force

• Gravity and gas pressure

• Nuclear force and weak force

• Friction and tension

Which event can disturb the balance of a gas cloud, leading to the initiation of star formation?

• A black hole forming nearby

• A supernova explosion

• A planet orbiting through it

• A comet passing by

As it spins, what shape does gravity pull the dust and gas into?

• A sphere

• A disk

• An ellipse

• An circle

What process begins when the core temperature of a young star reaches approximately 15 million degrees Celsius?

• Gravitational collapse

• Planetary formation

• Nuclear fusion

• Nuclear fission