Universe Unit Review

Front

What are gamma rays?

Back

Gamma rays are a type of electromagnetic radiation with the highest energy and are the most dangerous to living organisms.

Front

Which star is the coolest?

Back

The coolest star is a red star.

Front

What is a star?

Back

A star is a huge ball of very hot gas that emits light through a process called nuclear fusion.

Front

What is a comet?

Back

A comet is an icy small body that, when passing close to the sun, heats up and begins to release gases, forming a tail.

Front

What are galaxies composed of?

Back

Galaxies are composed of stars, dust, and gas held together by gravity.

Front

What is the process of nuclear fusion?

Back

Nuclear fusion is the process by which two or more atomic nuclei combine to form a heavier nucleus, releasing energy.

Front

What is the electromagnetic spectrum?

Back

The electromagnetic spectrum is the range of all types of electromagnetic radiation, including gamma rays, x-rays, ultraviolet, visible light, infrared, microwaves, and radio waves.

Front

What is the difference between a planet and a star?

Back

A planet is a celestial body that orbits a star and does not produce its own light, while a star is a massive celestial body that emits light and heat through nuclear fusion.

Front

What is the significance of gravity in galaxies?

Back

Gravity is the force that holds galaxies together, keeping stars, dust, and gas in orbit around the galaxy's center.

Front

What are the characteristics of a blue star?

Back

Blue stars are very hot and massive, with high energy output and a short lifespan.