Hi everyone.

My name is Mrs. Waller and I'm really looking forward to working with you today continuing to learn about the earth, sun, and moon.

And today we're going to be learning about why the sun appears to move across the sky.

Are you ready? So our learning outcome for today's lesson is that you will be able to explain why the sun appears to move across the sky.

Now think really carefully because I'm using that word here appears.

So before the lessons even really begun, I want you to think, does the sun really move across the sky or is it just that the sun appears to move? And if so, why do we think that happens? So here we have our key words for today's lesson, and don't worry at all if there's any of these words that you are not sure about because by the end of this lesson you'll be science vocabulary experts.

Let's take a look at the key words that we'll be mainly using today.

Sun, earth, rotating shadow, observe.

Now I'm fairly sure that you will have come across these words before.

So take a moment to have a think about which of these words do you know the meaning of? And maybe you could share your ideas with a partner.

Okay, so we've got some definitions of our keywords here.

We're not going to spend too much time looking at the definitions just now because all of these keywords and their definitions will be covered throughout the lesson.

So we'll have a quick look now, and it would be really good if you could look for these words throughout the lesson and think all the time about what these words mean.

So we have the sun is a star, and at the centre of our solar system, we have earth, which is the planet on which we live.

Did you know that one? And we also have that earth is always rotating.

So there's that word rotating and this means that it's spinning on its axis.

Now we have a shadow is formed when an opaque object blocks the light.

So you might want to have a chat with somebody about that word opaque as well, and think about what that means.

And finally, we have, when we observe, we look closely.

And don't forget, we can also use our other senses too.

Ready to move on, okay.

So here's our outline for today's lesson.

This lesson is in three separate parts.

And first of all, we will be looking at learning about observing the sun safely.

Now this is a really, really important part of the lesson because we're thinking about keeping ourselves safe.

So we're going to start off by thinking about the sun.

And we're thinking about what the sun is.

It's actually a big enormous, bigger than big, enormous bright ball of glowing gases.

Did you know that the sun was made up from gas? And we know that the sun is extremely bright.

In fact, it is so bright we must never, never look directly at the sun.

Even if you think, well, it's a cloudy day, it's gonna be okay to look at the sun today.

It's extremely dangerous to look at the sun.

In fact, I can say this, that looking at the sun is extremely dangerous.

It could actually damage your eyes, not just for a short period of time, but it could actually cause permanent damage to your eyes.

So this is coming with a really serious safety warning at the beginning of this lesson.

So how do we know about the sun? Well, we must be able to observe it somehow in a safe way.

Well, it's not recommended for us to be doing it, but we know that scientists, particularly space scientists called astronomers, they are able to observe the sun safely.

And they use a very special material called a filter, which they would place over the lens of either a very strong telescope or over a camera.

I'll tell you a little bit more about these filters that you actually can buy from places such as various sites on the internet, something called a solar viewer or some glasses called solar viewing glasses.

And they're made of a very special filtering material, very similar to the ones that scientists use over telescopes and cameras.

And this means that we can observe the sun safely, but only if you are using these special glasses or these special viewers.

If you have a look at the photograph there, you will see lots of people all gathering together.

And this was to view a really special event called a solar eclipse.

And you can see that these people here are wearing their solar viewing glasses so that they can observe what's happening with the sun.

Now we know that being able to make observations of the sun is really important to us to be able to know more and understand more about the sun.

Here we've got Sophia and Lucas and they're having a discussion about the sun.

Now Sophia is saying, I think the sun moves to different positions in the sky during the day.

Now what's Lucas saying? Well, Lucas is saying, well I actually don't agree with that.

I think that the sun stays in the same position in the sky all day and does not move.

So just take a moment to have a think about that and can you suggest any information that supports your argument with who you might agree with and why? So you might just want to pause the recording here and just share your ideas about what do you think.

Okay everyone, we are going to move on to our checks for understanding now.

And my first question for you is a, which statement is true question? So we've got three different options and I would like you to think about which one you think is the option that is true.

So is it A, it's safe to look directly at the sun? Is it B, it's only safe to look at the sun in the afternoon or is it C, it is never safe to look directly at the sun.

Which one do you think is true? And our answer here is C.

It is never safe to look directly at the sun.

And what I'm talking about here is directly with your eyes.

So we have been talking about using special filters and solar viewing glasses, but as a general rule, we must never look directly at the sun as it's extremely dangerous.

And as we know now it could permanently damage our eyes.

Are you ready for another check? So we've got a true or false question for you now and it's leading on from what we've just been thinking about.

So you should wear sunglasses to look directly at the sun.

Do you think that's true or do you think that's false? Yes, it's false, isn't it? Now here's the tricky part.

Are you able to explain why? Can you justify your answer? I'll give you a moment to gather your thoughts.

Okay, let's see what you were thinking.

Well, you must never look directly at the sun.

Even if you are wearing sunglasses, you know that sunglasses don't provide enough protection to your eyes.

They haven't got the special filters that astronomers use.

Moving onto your first practise task for this lesson, we would really love it if you could get a solar viewer.

So we want you to be able to look at the sun, but we need you to be able to do this really safely.

So speak to an adult and maybe if you could get one quite cheaply from an internet site, that would be absolutely fantastic 'cause we'd really like you to use a solar viewer to observe the position of the sun safely.

So we're going back to those conversations about it looks like the sun moves across the sky, but is it really moving across the sky? And the only way really to look at that is to view the sun safely.

So we'd like you to use a solar viewer to observe the position of the sun safely, remember, at different times of the day.

So it'd be really good if you could record the position of the sun in the morning.

And then again, you could have a look up into the sky around lunchtime and then at the very end of the day, and then maybe just before you're going to bed at nighttime.

And when you are doing this and making your observations, it would be really good if you could record what you notice.

So then we can talk about what do you notice about the position of the sun in the sky at different times? I think now would be a good time to pause the video and gather your thoughts.

You might want to prepare a table to record your results in or grab a whiteboard or a piece of paper or a notebook and get ready to observe and record.

So I'm hoping that you're coming back to this practise task, having been able to record the different positions of the sun in the sky at different times.

And I think what you should have noticed is that it does look like the sun changes position.

It appears to move across the sky during the day.

And what did you notice at nighttime? Well, at nighttime it does look like there's no sun in the sky.

So it looks like the sun disappears from the sky.

And if you were able to record your results in a table, something similar to this, then you'll have a really lovely set of data that we can have a look at where you've been able to talk about the different positions of the sun in the sky at different times during the day.

So here's my table of observations, and I've written down the different times that I was able to look up safely into the sky.

And I have also recorded my observations.

So in the morning at nine o'clock I observed that the sun was quite low over to one side of the sky.

And then when I looked again around lunchtime, I noticed that it looked like the sun had moved to a different position and it was above me and it seemed to be really high up in the sky.

So I checked again as I was coming home from school and it was about four o'clock and I noticed that the sun had moved to the opposite side of the sky and it was becoming really low in position again.

And that was really strange.

That really started to get me thinking.

And then when I checked at nighttime around 8:00 PM it looked like the sun had completely disappeared.

So this gives us lots to think about, doesn't it? I think it's time to move on to the next part of this lesson.

So we're moving on now to the second part.

And in this part we're going to be thinking about does the sun move across the sky? This is really our big question for the lesson, isn't it? Because we've observed that it looks like it's moving, but is it really moving? What's happening? So our observations have shown us that the sun looks like it moves across the sky during the day.

And I've got some photographs here.

Where, do you remember when we talked about how in the morning it might look like the sun is really low down on one side of the sky? And as the day moves on and it looks to be really high up in the sky, and then towards the evening it looks like the sun has moved across the sky to the other side and it's slowed down again.

And we also know that the sun looks like it disappears at nighttime.

So we have to start thinking about this, don't we, in terms of science and what's happening with our scientific explanations for this? So you might think that the sun travels around or you might think that the sun actually orbits, if you can remember that word from learning about objects in space, you might think that the sun orbits the earth.

However, scientists tell us that this is not true.

So has that stumped you a bit now or do you know what's actually happening? Let's think about this a little bit more.

So we know that the sun does not orbit the earth.

So you would think that it was the sun travelling around the earth that makes it look like it's moving around the earth from one side of the sky and then really high and then low again on the other side of the sky.

But that's not true.

So there's the earth and there's the sun.

And let's think about something else is moving here, something else is moving, which makes it look like the sun is moving.

Take a moment to really think about what's actually moving that makes it look like the sun is moving.

Do you know what is moving? So did you get that right? Yes, it's actually the earth that's moving, isn't it? It's not the sun that's moving, it's the earth and we know that the earth is spinning.

And we should also know that it takes 24 hours, which is the same as a day for the earth to rotate fully on its axis.

So we're bringing in lots of lovely key science vocabulary here to explain that the earth is spinning, but actually we are using the word that it's rotating and it's rotating on its axis.

So take a look at our scientific diagram and we can see the dotted line going straight through the centre of the earth to represent the axis.

And we can also see the earth is rotating in an anti-clockwise direction.

So it's the fact that the earth is rotating that makes it look like the sun is moving across the sky.

So as the earth spins to face the sun, this makes it look like the sun is moving.

So as earth spins away from the sun, this makes it look like the sun is getting lower in the sky.

And can you remember that that's why we say that the sun doesn't disappear at night.

It's always still there.

It's just that our part of the earth has rotated away from the sun.

So we are not facing the sun anymore, so we don't see the sun in the sky, but it is always still there.

Okay, everyone, are we ready to check our understanding of this part of the lesson? So our first check is in which way does the sun appear to change during the day? Is it that the sun appears to get brighter in the sky or does the sun appear to move in the sky or does the sun appear to get bigger in the sky? Take a moment to have a think.

And the answer here is B, yes, the sun appears to move across the sky.

Moving on now, so I have two images here for you to take a look at, image A and image B.

And they both show a person standing on the ground and there are various representations of the sun in the sky.

So which image A or B, do you think represents what you would see if you observe the sun safely during one day? And the answer is A, yes.

So it looks like the sun starts off quite low on one side of the sky and then moves to directly above you very high in the sky.

And again, it looks like it's moving so it finishes off the day low down on the opposite side of the sky.

I think representation B looks like the sun is moving higher and lower in the sky, but always directly above you.

And we know that that one isn't the case.

I've got one more check for understanding for you because there's some quite tricky scientific information in this lesson.

So I'm just double checking that you're 100% here on what you understand about the sun.

So which statement about why the sun appears to move is correct? Is it because the sun moves around the earth? Is it because the sun spins towards and away from earth? Or is it because earth rotates on its axis? And the answer here is C.

Yes, well done if you chose C, we know that it's the earth rotating that just makes it look like the sun is moving, but we know that the sun is not moving.

It's the earth that's moving instead, well done everyone.

We're moving on to our practise task now, and it would be really brilliant if you had a polystyrene ball with a pencil or a short stick through it to represent the earth and its axis.

And I've put my camera on just to show you that I've got a polystyrene ball here and I've put a pencil just into one end of it here.

It's quite easy just to push it in.

And I've got my polystyrene ball here and this represents the earth and the pencil.

I can spin it round like this, can't I, to represent the earth rotating on its axis.

So we've got our earth spinning on its axis, and then also you're going to need a partner to help you with this to hold a torch because the torch is going to represent the sun shining on earth.

So what do we need to do next? So we've got our diagram here, we've got our ball with our pencil through it, and we've got our dotted rotation line to show that you're going to be rotating the earth.

And we've got our torch switched on to represent the sun.

So as I've said already, I want you to slowly, very slowly spin the ball to show earth rotating on its axis.

And that would be a great idea if you could turn the lights off in the room because then you would be able to see more clearly where the sun shines, where the torch is shining, representing the sun.

So where it shines on earth as earth rotates.

And the reason that we are doing this is we're going to use this as a model to help you to explain what is really happening.

So we've talked about this a lot in this lesson today, and a lot of the time using a model really helps us to see something for ourselves that we are not actually able to experience in real life.

So the model is going to help us to see where the light from the torch is shining onto earth.

And that's going to help you to explain to a partner what's really happening when the sun is appearing to move across the sky, but we know that it's the earth rotating.

So it's definitely time for you to pause the video now and go and gather together all the things that you're going to need and have a go at this.

And let's see if you can get some fantastic scientific explanations.

So we're back together again, and we're going to share our ideas of how we use the model to explain what's really happening when the sun appears to move across the sky.

And we've got our scientific image here of our model with our bright torch representing the sun and our ball on a stick representing the earth rotating on its axis.

I'm really interested to hear what you found out.

When I used my model, I found that when earth rotates, the sun's light reaches different parts of earth.

Did you see the light from the sun shining on different parts of earth as earth was rotating so from earth, this makes it look like the sun is moving across the sky.

Did you find that on your model too? But we know that actually it is earth that's moving, not the sun.

So take a moment again to pause the video and share your explanations with somebody else and really take time to use the correct scientific vocabulary and get your explanation really correct in terms of some quite tricky science that's going on here, over to you.

So we're moving into the third and final part of this lesson today, and we are actually going to be using shadows as even more evidence to help us to explain what's happening when the sun appears to move across the sky.

So this part of the lesson is called changing shadows.

Let's think for a moment about shadows.

When something is opaque, Now, can you remember this word from previous learning? When something is opaque, it means it does not let the light pass through it.

So if an opaque object outside is blocking the sun's light, that's when we would see a shadow on a sunny day.

Take a look at this beautiful photograph of these trees outside and you can see the sun shining through and you can see the sun's light on the ground.

Can you see that? But we can see these long, dark shapes where the opaque objects, which in this case are the trees have blocked the light from the sun and we can see shadows forming on the ground.

Take a minute to just think about what shadows have you seen or have you made any shadows outside on a sunny day? Share your ideas.

Now we're always thinking about working like scientists, aren't we? So as, as well as having fun with shadows, we can also use our scientific skills.

We can observe shadows and we can observe them changing throughout the day.

Have you ever noticed that a shadow changes at different times throughout the day? You might have noticed that you might not.

So let's think about what happens to a shadow outside at different times of the day.

So we've got a beautiful image here of a person and their really clear shadow there behind them where the sun is shining and we know that that person is an opaque object.

They're not letting the lights through, they are blocking the sun's light and a shadow is forming.

So if that person was to stand there for a whole day and we were able to observe their shadow, what would happen to the shadow outside at different times of the day? And why do you think this happens? You might want to pause the video and share some of your ideas.

Now, what would be really great would be for you to go outside and try it for yourself.

So remember, it needs to be a sunny day and you need to go outside at different times and you can observe it for yourself and see what's happening to your shadow and try to explain why.

If it's a lovely day today, you might want to pause the video now and go outside and give this a go.

Okay, let's think again about the science that's happening behind this thing that we might see every day in our life.

You might not have ever wondered about it.

And now's the time to explain it using science.

So we know, don't we? We know that the earth is rotating.

So it's going to be something to do with this, because earth is rotating, light from the sun shines on objects from different directions throughout the day.

So let's use this drawing to help us to understand what's happening to shadows.

We know that the sun certainly does not move like this.

So this is a drawing to represent where the sun would be in the sky at different times of the day.

So let's take a look at the shadow in the morning, we can see that the shadow is in a certain direction behind the tree, and we can also see that the shadow is quite a long shadow.

Let's move on now as the earth has rotated, remember, the sun will now appear to be above us and quite high in the sky.

And we'll notice that something very different has happened with the shadow.

We can see that the shadow is in a different direction directly beneath the tree and it's quite a short shadow.

Okay, keep moving on.

Let's think about the earth continues to rotate.

So it would appear that the sun is now on the opposite side of the sky, but we do know, don't we, that it's not the sun moving, it's the earth that's rotating.

But let's think about again how the shadow is different.

So it's moving now in a different direction to where it was in the morning and at noon.

And also we have a long shadow again.

So again, we can use the idea of the earth rotating to explain why the direction of the shadow changes at different times of the day.

Let's keep thinking about this.

The earth is rotating.

We know that the direction of a shadow changes, but now we are thinking a bit more about the length of a shadow changing throughout the day.

We know that the sun makes a long shadow in the morning and late afternoon when the sun appears to be low in the sky.

Look at that fantastic photo of those people.

Look at those long leg.

But we know that this all depends on where the sun appears to be in the sky and the time of day.

We also know that at midday when the sun appears to be directly above us, then that's when our shadow is short.

It might be another good opportunity if it's a sunny day today for you to go back outside again and have another look.

Moving on to our checks for understanding now.

So shadows are formed during the day when an opaque object blocks the light.

Where does the light come from? Is it A, the sun, B, the moon or C, the streetlights? Yep, it is A, the sun.

Because remember the question is asking you about shadows during the day.

Moving on to our next question now, Jacob and Sophia observed the shadow of a fence post in the school field one morning.

So let's take a look at our diagram.

We've got our fence post in the ground, we've got our sun and we've got the dark shadow appearing on the ground.

So this image shows the shadow one morning.

Our question is what will happen to the shadow at home time later in the day? Do you think A, the shadow will have changed colour, do you think B, the shadow will have changed direction or do you think C, the shadow will have changed shape? And the correct answer is B, the shadow will have changed direction because we know don't we, that as the sun appears to move across the sky during the day, shadows change direction.

Our next question, and we are still thinking about Jacob and Sophia.

So we've got the same fence post and we've got the same shadow.

And this again was one morning.

Now they're really interested now to think about the shadow at lunchtime and they want to know what will happen to the length of the shadow at lunchtime.

So do you think A, it will be longer, B, it will be shorter, or C, it will be the same length? And the answer here is B, it will be shorter.

Well done if you got that one right, because we know that at lunchtime, at midday, the sun appears to be directly above us, so the sun's light will be shining directly down onto the object, which makes the shadow shorter.

Well done everyone, onto our final practise task now.

So we're still going to use our polystyrene ball and our pencil, which represents earth and its axis.

But this time if you've got a really small stick like a craft matchstick, if you can push that into the ball with a little piece of sticky tack and that's going to represent a shadow stick.

Now I'd like you to ask a partner again to hold that torch and that again is going to represent the sun shining on earth.

So we've got our diagram here to show you our ball with our pencil.

And if you just notice there we've got that little short stick and that is our shadow stick.

So again, your person holding the torch, keep nice and still to represent the light from the sun.

Again, we're going to need to dim the lights for this one.

Slowly spin the ball to show earth rotating on its axis.

And what I'd really like you to do is use this model to explain why shadows change throughout the day.

It's a good time to pause the video, gather together what you are going to need and have a go at this task.

Okay, so hopefully we've had some time now to try out the activity and we're thinking about why shadows change throughout the day.

Well, the first thing that I observed was that the matchstick blocked the light and made a shadow so that matchstick is made from an opaque material.

As I slowly rotated earth on its axis, I observed that the shadow changed direction.

Did you notice that too? Did you look for direction? Did you look for anything else? Well, I kept my activity going.

I was really interested in this.

So I continued to explore and I looked at the length of the shadow.

So I also observed that the shadow started long and then as earth rotated, it very gradually got shorter.

But then as I kept rotating earth, the shadow became longer again.

Did you find that too? Finally, I'm thinking about what happens in real life.

Shadows change direction and size when the sun shines on them from different directions.

And we know that this isn't because the sun is moving, we know that this is because earth is rotating on its axis.

So lots of really tricky learning here today, everybody.

I'm really proud of how hard you've worked, well done.

So let's take a moment now to recap our learning from the whole of today's lesson.

So first of all, if we remember that it is extremely dangerous to look directly at the sun.

So what else have we learned today? We know that the sun does not move around the earth.

It does not orbit the earth.

And we know that because the sun appears to move across the sky, but we know that it's not, and that's because it's the earth that's rotating on its axis.

Finally, we know that because earth is rotating, we can observe shadows changing throughout the day.

And can you remember different ways that we can see changes in shadows? Yes, we can see shadows can change direction and also that they can change lengths depending on the time of day.

Well done, so that's the end of our lesson, and I've really enjoyed learning about some really tricky scientific things that we might observe happening in our lives every day.

It really helps to be able to understand the science behind it, doesn't it? Well done everyone, and I really look forward to another lesson with you another time.