Space claims, down to Earth.
A few cosmic statements to sort out.
Ten questions, with the answers explained. Try them in your head, then open each answer when you're ready.
Play this quiz →QUESTION 1 / 10
Mercury and Venus have no natural moons.
- True
- False
Show answer & explanation+
True
They are the two planets in our solar system without known natural satellites.
QUESTION 2 / 10
The Sun is a solid rocky ball.
- True
- False
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False
The Sun is made of hot plasma, mostly hydrogen and helium.
QUESTION 3 / 10
A comet's tail always trails directly behind its direction of travel.
- True
- False
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False
Solar radiation and the solar wind drive comet tails generally away from the Sun.
QUESTION 4 / 10
A solar flare is an eruption of energy from the Sun.
- True
- False
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True
Solar flares are intense releases of electromagnetic radiation associated with magnetic activity.
QUESTION 5 / 10
Earth's axis is tilted relative to its orbital plane's perpendicular.
- True
- False
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True
That axial tilt is central to Earth's seasons.
QUESTION 6 / 10
The Moon's dark plains are called maria.
- True
- False
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True
Maria is Latin for seas, though these lunar plains are made of solidified volcanic rock.
QUESTION 7 / 10
A star's apparent brightness depends partly on its distance from us.
- True
- False
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True
Two equally luminous stars can appear different in brightness if they are at different distances.
QUESTION 8 / 10
An astronaut's mass vanishes in orbit.
- True
- False
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False
Mass remains. The feeling of weightlessness comes from falling continuously around Earth.
QUESTION 9 / 10
Jupiter is a terrestrial rocky planet like Earth.
- True
- False
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False
Jupiter is a gas giant, very different in structure from the rocky inner planets.
QUESTION 10 / 10
Some planets outside our solar system have been discovered orbiting other stars.
- True
- False
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True
These are exoplanets, planets beyond our solar system.