30.1
Gravity and weight
Weight = mass × g, gravity on other worlds, and how gravity holds the Moon and the planets in orbit.
30.2
The Solar System
The Sun, its eight planets and their orbits, moons, asteroids, comets and satellites, and the scale of it all.
30.3
Day, night and the seasons
Why we have day and night, why the Earth's tilt gives us seasons, and how day length changes round the world.
30.4
Stars, galaxies and the light year
The Sun as a star, our galaxy and others, and measuring the vast distances of space in light years.
Daily 5
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What this unit covers
Mapped to the KS3 national curriculum (Physics: space physics).
| Programme of study | Lesson |
|---|---|
| gravity force, weight = mass × gravitational field strength (g); on Earth g = 10 N/kg, different on other planets and stars | 30.1 |
| gravity forces between the Earth and the Moon, and between the Earth and the Sun (qualitative only) | 30.1, 30.2 |
| our Sun as a star, other stars in our galaxy, other galaxies | 30.4 |
| the seasons and the Earth's tilt, day length at different times of year, in different hemispheres | 30.3 |
| the light year as a unit of astronomical distance | 30.4 |
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