QS
Which planet is closest to the Sun?
Mercury
What is the main gas in Venus’s atmosphere?
Carbon dioxide
Which planet is the only known planet with life?
Earth
Which planet have humans visited with spacecraft the most?
MARS
How many terrestrial planets are in the Solar System?
4
How long is one day on Mercury compared to Earth days?
About 59 Earth days
Which planet is known as Earth’s “sister planet”?
Venus
Which giant volcano is located on Mars?
Olympus Mons
What is the name of the first rover to successfully land on Mars?(its name means ‘traveler’ or 'a person who stays somewhere temporarily' in English)
Sojourner
What are terrestrial planets mainly made of?
Rock and metal
Why does Mercury have almost no atmosphere?
Its weak gravity cannot hold gases for long.
Why does Venus rotate backwards?
a huge collision that changed its rotation(no evidences though)
Why is water difficult to exist on Mars today?
Because Mars has low pressure and very cold temperatures.
Why do scientists send rovers to Mars?
To study the planet and search for signs of past life.
Why are terrestrial planets called “rocky planets”?
Because they have solid rocky surfaces.
Why does Mercury have extreme temperature changes?
Because it has almost no atmosphere to keep heat.
What causes Venus to be the hottest planet?
Its thick carbon dioxide atmosphere creates a strong greenhouse effect.
Why does Earth have a strong magnetic field?
Due to movement of molten iron in its core.
Why is landing on Venus difficult for spacecraft?
Because of extreme heat and pressure.
What is the largest terrestrial planet?
EARTH
Explain why Mercury is not the hottest planet even though it is closest to the Sun.
Mercury lacks a thick atmosphere to trap heat, while Venus’s atmosphere keeps heat trapped.
Compare Earth’s atmosphere with Mars’s atmosphere.
Earth has a thick nitrogen-oxygen atmosphere, while Mars has a thin carbon dioxide atmosphere.
Explain the greenhouse effect on Venus.
Thick carbon dioxide traps heat from the Sun, making Venus extremely hot.
Explain why terrestrial planets are important for space exploration.
They may contain resources, clues about life, and possible future homes for humans.
Describe two major differences between terrestrial planets and gas giants.
Terrestrial planets are rocky and smaller, while gas giants are larger and mostly made of gas.