Nebula

The term 'nebulae' originally described objects that appeared fuzzier than stars. Many of these were later identified as galaxies. Nebulae form in various ways, including from the remnants of exploding stars, fading smaller stars, or interstellar gas that coalesces under gravity.

What did the term originally refer to before astronomers identified them as galaxies?

• Comets

• Bright stars

• Planets

• Objects that appeared fuzzier than stars

How are nebulae formed from exploding stars?

• Through the fusion of hydrogen atoms

• From the remnants of the explosion

• By the collision of two stars

• By the gravitational pull of a black hole

Which of the following is NOT a way nebulae are formed?

• From the remnants of smaller stars

• From exploding stars

• From the collision of galaxies

• From interstellar gas

What happens to smaller stars that contribute to the formation of nebulae?

• They turn into planets

• They become black holes

• They fade away

• They explode violently

What role does gravity play in the formation of nebulae from interstellar gas?

• It heats the gas

• It pulls the gas together

• It disperses the gas

• It changes the gas into liquid