0:00:05 > 0:00:09# If you've got a question and you don't know where to go
0:00:09 > 0:00:11# Ask Nina for help cos she's got a science show
0:00:11 > 0:00:14# She mixes all their senses by helping all her fans
0:00:14 > 0:00:18# By doing her experiments with potions and with bangs
0:00:18 > 0:00:19# Touch your tongue
0:00:19 > 0:00:20# Fingers
0:00:20 > 0:00:23# Eyes, ears, nose
0:00:23 > 0:00:26# Nina and the Neurons find out what you need to know
0:00:26 > 0:00:29# Nina and the Neurons find out what you need to know
0:00:29 > 0:00:33# Luke helps us with our eyes and Felix with our touch
0:00:33 > 0:00:36# Ollie sniffs out smells and scents and Belle she hears so much
0:00:36 > 0:00:39# Bud is Ollie's brother he helps with our taste
0:00:39 > 0:00:43# They're Nina's little Neurons and they're coming to your place
0:00:43 > 0:00:47# Touch your tongue... fingers, eyes, ears, nose
0:00:47 > 0:00:50# Nina and the Neurons find out what you need to know
0:00:50 > 0:00:53# Nina and the Neurons find out what you need to know
0:00:53 > 0:00:56# Oh yeah! #
0:00:58 > 0:01:00Oh, hello there.
0:01:00 > 0:01:03I'm just having my breakfast - some yummy cereal.
0:01:03 > 0:01:06It's still early and the sun is just coming up.
0:01:06 > 0:01:07SHE GIGGLES
0:01:07 > 0:01:09BEEPING
0:01:09 > 0:01:13I hear a beep, I see a flash. I wonder what they're going to ask.
0:01:18 > 0:01:20BOTH: Hi, Nina.
0:01:20 > 0:01:21Hi.
0:01:21 > 0:01:24We've got a question for you.
0:01:24 > 0:01:26Why do we have night and day?
0:01:26 > 0:01:28That's a great question.
0:01:28 > 0:01:31Why do we have night and day? It's daytime now.
0:01:31 > 0:01:34Before that it was night-time and it was dark
0:01:34 > 0:01:36and I was tucked up asleep in bed.
0:01:36 > 0:01:38This'll be really exciting to explore.
0:01:38 > 0:01:41Come down to my workshop and we'll investigate.
0:01:41 > 0:01:45BOTH: See you soon, Nina. Bye!
0:01:45 > 0:01:47Bye.
0:01:47 > 0:01:50Well, I'm going to need some help to answer this one
0:01:50 > 0:01:54and I know just who to ask. OK, Neurons, time to get to work.
0:02:07 > 0:02:10ALL: Neurons at the ready, Nina.
0:02:10 > 0:02:14OK, today's question is why do we have night and day?
0:02:14 > 0:02:18Which Neuron do you think will be most useful in helping us
0:02:18 > 0:02:21- find the answer? - ALL: Me! Me! Me!
0:02:21 > 0:02:23Will it be fabulous Felix?
0:02:23 > 0:02:28I can help so much very much, if you need the sense of touch.
0:02:28 > 0:02:30Will it be beautiful Belle?
0:02:30 > 0:02:32I send messages to brain from ear.
0:02:32 > 0:02:34If there's a sound I'll help you hear.
0:02:34 > 0:02:36Will it be lovely Luke?
0:02:36 > 0:02:38For looking and seeing, day or night,
0:02:38 > 0:02:41I'll help you with your sense of sight.
0:02:41 > 0:02:43Will it be awesome Ollie?
0:02:43 > 0:02:45If it's pongy or whiffy but you can't tell,
0:02:45 > 0:02:48my messages help your sense of smell.
0:02:48 > 0:02:50Or will it be baby Bud?
0:02:50 > 0:02:54Sour, salty, bitter or sweet, I'm your taste buddy whenever you eat.
0:02:58 > 0:02:59It's Luke!
0:03:08 > 0:03:12Cool, Nina. I'll be looking out to help you.
0:03:12 > 0:03:15Today's question is why do we have night and day?
0:03:15 > 0:03:19Because we see when it's night or day, Luke, our sight Neuron,
0:03:19 > 0:03:22will be helping us. But stand by, Neurons.
0:03:22 > 0:03:25I have a feeling I may need help from all of you.
0:03:25 > 0:03:29Right, I need to get the workshop ready before the explorers arrive.
0:03:29 > 0:03:32Sophie loves cupcakes and Logan likes smoothies.
0:03:32 > 0:03:35But they both want to know why do we have night and day?
0:03:35 > 0:03:38The sun wakes me up in the morning.
0:03:38 > 0:03:40I see stars at night time.
0:03:40 > 0:03:43Why do we have night and day?
0:03:43 > 0:03:47So today, for one day only, Sophie and Logan become the explorers!
0:03:52 > 0:03:54- Hi, guys.- BOTH: Hi, Nina.
0:03:54 > 0:03:58Welcome to my workshop and thank you for your great question -
0:03:58 > 0:03:59why do we have night and day?
0:03:59 > 0:04:03To find out the answer, let's start by using our senses.
0:04:03 > 0:04:06ALL: Whoop-whoo! A senses experiment.
0:04:06 > 0:04:07We're ready, Nina.
0:04:07 > 0:04:10Let's have a look at these two pictures.
0:04:10 > 0:04:13So, which one of these is daytime?
0:04:13 > 0:04:16- That one.- Yeah, you're right.
0:04:16 > 0:04:19And what does this picture show us?
0:04:19 > 0:04:21Night-time.
0:04:21 > 0:04:24That's easy, Nina - it's dark!
0:04:24 > 0:04:27Exactly. At night-time we can't see the sun
0:04:27 > 0:04:28and it's dark outside.
0:04:28 > 0:04:30That's when we go to bed.
0:04:30 > 0:04:34But in the day, the sun is in the sky and it's light outside.
0:04:34 > 0:04:37So how does the sun go up and down?
0:04:37 > 0:04:41Well, let me dim the workshop lights...
0:04:41 > 0:04:44and we'll look at this model house to find out.
0:04:45 > 0:04:49Now, we're going to pretend that this torch is the sun.
0:04:49 > 0:04:52You should never look directly at the sun.
0:04:52 > 0:04:54It's very dangerous for your eyes.
0:04:54 > 0:04:57But because this is a pretend sun it's OK.
0:04:57 > 0:05:02So, first thing in the morning the sun is shining from over here.
0:05:02 > 0:05:06So have a look at the shadows, explorers. What do you notice?
0:05:06 > 0:05:10- There's a big shadow at the back of the house.- OK.
0:05:10 > 0:05:13And in the middle of the day,
0:05:13 > 0:05:17- can you see what's happened to the shadow?- It's moved.
0:05:17 > 0:05:18Yeah.
0:05:18 > 0:05:22Let's see what happens to the shadows near the end of the day.
0:05:22 > 0:05:25Ooohh.
0:05:25 > 0:05:28- The shadow's at the front now. - Well spotted!
0:05:28 > 0:05:33So it looks as though the sun moves across the sky during the day.
0:05:33 > 0:05:36Now I'll turn the lights back up.
0:05:40 > 0:05:42Before clocks and watches were invented,
0:05:42 > 0:05:44people used the sun to tell the time.
0:05:44 > 0:05:48They would look at where the shadows were to find out
0:05:48 > 0:05:50if it was morning, lunchtime or evening.
0:05:50 > 0:05:54Lunchtime - that's my favourite time of day.
0:05:54 > 0:05:59Well, Bud, you can tell it's lunchtime by using this...
0:05:59 > 0:06:00a sun clock.
0:06:03 > 0:06:10It's called a sundial and we'll see how it works if I dim the lights.
0:06:13 > 0:06:16Put the torch on again.
0:06:16 > 0:06:20So let's start in the morning, when the sun shines from over here.
0:06:20 > 0:06:26- So, explorers, where's the shadow pointing?- There.- Yeah.
0:06:27 > 0:06:33And now it's the middle of the day and the sun is shining from here.
0:06:33 > 0:06:35So where's the shadow pointing?
0:06:35 > 0:06:38- There.- Yeah.
0:06:38 > 0:06:42And now it's nearly night-time. The sun is setting.
0:06:42 > 0:06:45- Where's the shadow pointing now? - There it is!
0:06:45 > 0:06:50That's right. And that's how people used shadows to tell the time.
0:06:52 > 0:06:54That's marvellous, Nina.
0:06:54 > 0:06:58So now we know we see the sun in the day when it's light.
0:06:58 > 0:07:01But we don't see the sun in the night when it's dark.
0:07:01 > 0:07:05The sun's light moves throughout the day, making shadows that move
0:07:05 > 0:07:09- and change shape, too. - Well remembered, Neurons.
0:07:09 > 0:07:12The sun looks like it's moving but really the sun doesn't move.
0:07:12 > 0:07:15We're the ones that are moving.
0:07:15 > 0:07:17Let's go somewhere fun to find out more.
0:07:25 > 0:07:29- Where do you think we're going today? - Nina said it was somewhere fun.
0:07:29 > 0:07:33I hope there's a picnic. Picnics are fun!
0:07:33 > 0:07:38- It doesn't smell like food.- Sharpen your senses, Neurons, we're here.
0:07:39 > 0:07:42So far we've out that when it's daytime the sun is shining
0:07:42 > 0:07:44and it's light.
0:07:44 > 0:07:48And at night-time we can't see the sun shining, so it's dark outside.
0:07:48 > 0:07:52And we also found out that it looks like the sun is moving
0:07:52 > 0:07:54across the sky during the day.
0:07:54 > 0:07:57But it's not the sun that's moving, it's us.
0:07:57 > 0:08:01I can show you what happens with this fairground carousel.
0:08:02 > 0:08:06We are going to pretend that this carousel is like planet Earth,
0:08:06 > 0:08:09where we live. And here behind us is our pretend sun.
0:08:09 > 0:08:13If that was really the sun, it would feel very hot, Nina.
0:08:13 > 0:08:16And it would be MASSIVE!
0:08:16 > 0:08:20At the moment, the sunshine is on this side of the carousel.
0:08:20 > 0:08:25Now, Logan, I would like you to go and take a seat on the daytime side.
0:08:32 > 0:08:36And over on the opposite side of the carousel...
0:08:40 > 0:08:43..it's night-time, where we can't see the sun.
0:08:43 > 0:08:47Sophie, I'd like you to sit on the night-time side. On you go.
0:08:55 > 0:08:57This is just like planet Earth.
0:08:57 > 0:09:01Half of the planet is in the light, and the other half is in the dark.
0:09:01 > 0:09:04But it doesn't stay like that.
0:09:04 > 0:09:06So how can we get Sophie into the daytime
0:09:06 > 0:09:08and Logan into the night-time?
0:09:08 > 0:09:11Well, let's see. OK, guys, here we go.
0:09:29 > 0:09:33Now, Sophie, you can see the sun, so it's daytime.
0:09:33 > 0:09:37And, Logan, it's night-time for you because you can't see the sun.
0:09:37 > 0:09:40So let's keep going and if you see the sun shout, "Day!"
0:09:40 > 0:09:44And if you can't see it shout, "Night!" Here we go!
0:09:55 > 0:09:56- SOPHIE:- Night!
0:09:57 > 0:09:58- LOGAN:- Day!
0:10:03 > 0:10:04- LOGAN:- Night!
0:10:08 > 0:10:10- SOPHIE:- Day!
0:10:14 > 0:10:15- SOPHIE:- Night!
0:10:16 > 0:10:17- LOGAN:- Day!
0:10:21 > 0:10:22- SOPHIE:- Night!
0:10:24 > 0:10:26Day!
0:10:34 > 0:10:38Well done, explorers, you were great at being the pretend planet Earth.
0:10:38 > 0:10:40Now, when you were on the ride,
0:10:40 > 0:10:43- did it look like the pretend sun was moving?- BOTH: Yes!
0:10:43 > 0:10:47I was watching the pretend sun and it didn't move.
0:10:47 > 0:10:49It only looked like it was moving to you
0:10:49 > 0:10:51because you were spinning around.
0:10:51 > 0:10:54And the real Earth does the same thing, too.
0:10:54 > 0:10:56And this is a model of the Earth.
0:10:56 > 0:10:59Nina, the Earth is broken. It looks wonky.
0:10:59 > 0:11:03It's not broken, Belle, it's tilted in real life,
0:11:03 > 0:11:05exactly like this model.
0:11:05 > 0:11:07And we live up here.
0:11:07 > 0:11:10And the Earth spins like the carousel did.
0:11:13 > 0:11:15And as it turns round,
0:11:15 > 0:11:18we go from daytime...
0:11:18 > 0:11:20into night-time.
0:11:20 > 0:11:23And back round into daytime again.
0:11:23 > 0:11:27From where we are on the Earth it looks like the sun's moving,
0:11:27 > 0:11:31but it stays still. Just like our pretend sun stayed still
0:11:31 > 0:11:34when you were moving around in the carousel.
0:11:34 > 0:11:38The Earth spins and goes from daytime to night-time,
0:11:38 > 0:11:41when people go to sleep.
0:11:41 > 0:11:44SHE SNORES
0:11:44 > 0:11:48So it looks like the sun is moving across the sky,
0:11:48 > 0:11:52but it's really the Earth that is spinning.
0:11:52 > 0:11:54Well remembered, Neurons.
0:11:54 > 0:11:58# Nina and the Neurons. #
0:11:58 > 0:12:01So, your question was, why do we have night and day?
0:12:01 > 0:12:03And I think we've answered it.
0:12:03 > 0:12:06When we can see sunlight, that's daytime.
0:12:06 > 0:12:09When we turn away from the sun it goes dark,
0:12:09 > 0:12:11and that's when we get night-time.
0:12:11 > 0:12:14It looks like the sun is moving but it's not -
0:12:14 > 0:12:16we're the ones that are moving.
0:12:16 > 0:12:20- So I hope that's answered your question.- BOTH: Thanks, Nina. Bye.
0:12:20 > 0:12:22You're welcome. Bye!
0:12:24 > 0:12:28If you want to know more about the science that's all round us,
0:12:28 > 0:12:32go to the Nina section on the CBeebies website. Have fun!
0:12:32 > 0:12:34# Every day the sun comes up
0:12:34 > 0:12:37# It brightens up the sky
0:12:39 > 0:12:41# A brand-new day to understand
0:12:41 > 0:12:43# A chance to ask ourselves why? #
0:12:43 > 0:12:44Why?
0:12:44 > 0:12:47# There's a world of possibilities
0:12:47 > 0:12:50# Outside our front door
0:12:50 > 0:12:54# So every day take a look around
0:12:54 > 0:12:55# And explore
0:12:55 > 0:12:58# Explore
0:12:58 > 0:13:00# Exploring in the garden
0:13:00 > 0:13:01# Rocks
0:13:01 > 0:13:03# Exploring in the park
0:13:03 > 0:13:04# Rivers
0:13:04 > 0:13:06- # Exploring in the daytime - Mountains!
0:13:06 > 0:13:09- # And even when it's dark - Planets!
0:13:09 > 0:13:11# Look at the Earth
0:13:11 > 0:13:13# Look at the sky
0:13:13 > 0:13:15# Look at the world before us
0:13:15 > 0:13:17# Explore explore explore
0:13:17 > 0:13:20# We're always on the lookout
0:13:20 > 0:13:23# We're Earth explorers
0:13:23 > 0:13:26- # We're Earth explorers- Oh-oh
0:13:26 > 0:13:30# We're Earth explorers. #
0:13:30 > 0:13:34Remember, exploring is about looking at the world around us,
0:13:34 > 0:13:36asking why, and finding out the answer.
0:13:36 > 0:13:40So, whether it's deep underground, at the end of your playground,
0:13:40 > 0:13:42or way up above the clouds,
0:13:42 > 0:13:45let's keep exploring our exciting world. See you again soon. Bye!
0:13:46 > 0:13:48ALL: Bye!
0:13:48 > 0:13:50Subtitles By Red Bee Media Ltd