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# Spinning and orbiting

Year 7 Earth and space · The Earth and the sun

<!-- Speaker note: Students distinguish the Earth's rotation from its revolution, link each to day and night and the year, and describe the tilted axis that keeps its direction (AC9S7U03, node 1, a hinge node). About 20 minutes (Engage and Explore 7 min · Explain 8 min · Evaluate 3 min · Typical adds 1 min, Wider about 3 min). -->

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## Today

**We are learning to** the Earth rotates (spins on its axis) once a day, causing day and night, and revolves (goes round the sun) once a year. Its axis is tilted and always points the same way in space.

- I can explain the difference between rotation and revolution.
- I can link rotation to day and night, and revolution to the year.
- I can describe the Earth's tilted axis and how it points.

<!-- Speaker note: Before class: A concept tutorial for introducing or revising the idea; it does not replace a physical model (a torch and a globe, or students walking round a lamp while turning). Set the width with `?width=minimum`, `typical` (default) or `wider`. The hinge confusion is between rotation and revolution. The board plays them separately: one day, then one year. Board notes: sizes and distances are not to scale (the board says so). The top view shows the axis as a white line marked N, pointing the same way all year; the side view keeps the sun on the left and shows how far the axis leans towards or away from it. Day lengths are calculated for the real latitude and date (ignoring the bending of light by the air). -->

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## Why it matters

> Right now you are spinning at about 1400 km/h (in Canberra) and flying round the sun at about 107 000 km/h. You don't feel either.

<!-- Speaker note: In Year 6 you modelled day and night. This lesson puts both of the Earth's movements together. -->

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<span style="background:#dbeafe; color:#1a1a1a; border:1.5px solid #3b82f6; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">💬 Discussion</span>

## Engage: predict

**What causes day and night?**

- The Earth spins on its axis once a day
- The sun goes round the Earth once a day
- The moon blocks the sun at night
- The Earth goes round the sun once a day

<!-- Speaker note: What happens: The Earth spins (rotates) on its axis once a day. The half facing the sun has day. Going round the sun (revolving) takes a whole year. Take two or three predictions before anyone runs it. -->

<!-- Speaker note: Teacher: count how many chose 'the Earth goes round the sun once a day'. -->

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<span style="background:#fef3c7; color:#1a1a1a; border:1.5px solid #f59e0b; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✍️ Activity</span>

## Explore it

{{embed: https://studio.learningwaypoints.com/tutorials/_playground-board/index.html?id=deck%2Fscience%2Fearth-7%2Fspin-orbit%2Fstep-2&code=widget%3A+sky%0Amode%3A+earth%0A&fresh=1}}

[Open this step in the tutorial](https://studio.learningwaypoints.com/tutorials/science/earth-7/spin-orbit/?full=step-2#step-2)

<!-- Speaker note: Press **Play a day** and watch the orange person on the equator, and Canberra in the side view. Then press **Play a year**. Watch which way the axis (the white line marked N) points as the Earth goes round. -->

<!-- Speaker note: Teacher: ask what the N line does over the year. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## What happened?

* The Earth spins (rotates) on its axis once a day. The half facing the sun has day. Going round the sun (revolving) takes a whole year.

<!-- Speaker note: Reveal after running. Ask who predicted it, and what made them think so. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Which cycle

**Rotation (spinning) or revolution (orbiting)?**

Groups: Rotation · Revolution

Takes about 24 hours · Takes about 365¼ days · Causes day and night · The sun seems to rise in the east · Goes through the seasons once · Different stars are in the night sky in June and December

* Answer: Takes about 24 hours → Rotation; Takes about 365¼ days → Revolution; Causes day and night → Rotation; The sun seems to rise in the east → Rotation; Goes through the seasons once → Revolution; Different stars are in the night sky in June and December → Revolution

<!-- Speaker note:  -->

<!-- Speaker note: Teacher: the sort is the checkpoint. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Spins in a year

**About how many times does the Earth spin in one trip round the sun?**

* Answer: 365

<!-- Speaker note: About 365¼ times, which is why we add a leap day every four years. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## The axis

**During Play a year, what did the Earth's axis do?**

- It flipped over at midyear
- It always leaned towards the sun
- It stood straight up
- It kept pointing the same way in space, so sometimes the north end leans towards the sun and sometimes away

* Answer: It kept pointing the same way in space, so sometimes the north end leans towards the sun and sometimes away

<!-- Speaker note:  -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Elaborate: what a person notices across a year

**A student in Canberra records sunset time every week for a year. What pattern will they find?**

- Sunset changes randomly
- Sunset is latest in June and earliest in December
- Sunset gets later until early January, then earlier until mid-June, then later again: a yearly cycle
- Sunset is at the same time every day

* Answer: Sunset gets later until early January, then earlier until mid-June, then later again: a yearly cycle

<!-- Speaker note: What this step is for: Describing what an observer experiences links the two cycles to everyday evidence. -->

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<span style="background:#fef3c7; color:#1a1a1a; border:1.5px solid #f59e0b; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✍️ Activity</span>

## Elaborate: different places

{{embed: https://studio.learningwaypoints.com/tutorials/_playground-board/index.html?id=deck%2Fscience%2Fearth-7%2Fspin-orbit%2Fstep-5&code=widget%3A+sky%0Amode%3A+earth%0Aplace%3A+Darwin%0A&fresh=1}}

[Open this step in the tutorial](https://studio.learningwaypoints.com/tutorials/science/earth-7/spin-orbit/?full=step-5#step-5)

<!-- Speaker note: What this step is for: Comparing places at the same date shows the tilt matters differently at different latitudes. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Longest day

**On 22 December, where is the day longest: Darwin, Canberra, Hobart or Davis station (Antarctica)?**

- Davis station: the sun doesn't set at all
- Canberra
- Darwin
- They are all 12 hours

* Answer: Davis station: the sun doesn't set at all

<!-- Speaker note:  -->

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## Evaluate: look back

Write one sentence: "At first I thought… Now I think… because…"

**Revision summary**

- **Rotation:** the Earth spins on its axis once a day: day and night.
- **Revolution:** the Earth goes round the sun once a year (about 365¼ days, about 365 spins).
- The **axis is tilted 23.4°** and always points the same way in space, so each hemisphere leans towards the sun for half the year.

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Exit ticket

**What is the difference between rotation and revolution?**

* Rotation is the Earth spinning on its axis (once a day, causing day and night); revolution is the Earth travelling round the sun (once a year).

<!-- Speaker note: Students answer on paper or a mini whiteboard before the reveal. Anyone who cannot answer needs the main idea again next lesson. Where this leads: Next: seasons (node 4), then the moon (nodes 2, 3 and 5). In class: a lamp and a globe or a ball on a skewer; students walk the orbit while turning. -->