Grade 9 · Science · Unit 11 of 11
Sun, Solar System & Universe
Our place in space
What your child practises
The Sun's role on Earth, the planets and other bodies, distances in AU and light-years, seasons, eclipses, tides and the aurora, evidence for the Big Bang, and the benefits and costs of space exploration. Indigenous ways of knowing about the sky are not covered yet and need community review.
Ontario Curriculum expectation: E1.1, E1.2, E1.3, E2.1, E2.2, E2.3, E2.4, E2.5, E2.6 · the Sun and its energy, the solar system and universe, distances and scale, astronomical phenomena, and the impacts of space exploration
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
In a lunar eclipse…
- the Moon moves out of orbit
- Earth passes between the Sun and the Moon
- the Sun is hidden by Venus
- the Moon passes between the Sun and Earth
Show answer
Earth passes between the Sun and the Moon
Hint: Earth's shadow falls on the Moon.
Question 2
The four inner planets are…
- rocky (terrestrial)
- made of the Sun
- all ice
- gas giants
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rocky (terrestrial)
Hint: Mercury, Venus, Earth and Mars have solid surfaces.
Question 3
Space exploration has benefits and costs. Which is a benefit?
- Satellites help track weather, climate and natural disasters
- It makes all other research unnecessary
- It has no cost
- It never produces any debris
Show answer
Satellites help track weather, climate and natural disasters
Hint: Weigh the benefits against the cost, debris and environmental impact of launches.
Question 4
What causes day and night on Earth?
- Earth rotating on its axis
- the Moon blocking the Sun
- the Sun spinning around Earth
- Earth orbiting the Sun in a day
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Earth rotating on its axis
Hint: Rotation takes about 24 hours.
Question 5
One astronomical unit (AU) is about 150 million km. An object orbits 4 AU from the Sun. About how many million km is that?
answer boxM km
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600 M km
Hint: 4 × 150 = 600 million km.
Question 6
What are the northern lights (aurora borealis)?
- reflections from the Moon
- light from distant cities
- light made when charged particles from the Sun hit gases in Earth's atmosphere
- lightning in clouds
Show answer
light made when charged particles from the Sun hit gases in Earth's atmosphere
Hint: Earth's magnetic field guides the particles toward the poles.