Herschel

Download Subtitles

Transcript

0:00:02 > 0:00:04This is Absolute Genius.

0:00:04 > 0:00:09Dive into a world of action, adventure and explosions.

0:00:09 > 0:00:12Each show will introduce you to a different genius.

0:00:12 > 0:00:16An amazing person that had a genius idea that shaped the world.

0:00:17 > 0:00:19They will inspire us to come

0:00:19 > 0:00:22up with our own genius idea at the end of each show.

0:00:22 > 0:00:24But will it be any good?

0:00:24 > 0:00:27Will it be any good?!

0:00:27 > 0:00:28It'll be Absolute Genius.

0:00:30 > 0:00:34On today's show - we prepare for deep impact...

0:00:37 > 0:00:41..as we investigate the mysterious world of comets.

0:00:42 > 0:00:48And discover how a genius astronomer helped to map out the universe.

0:01:33 > 0:01:35- This way mate.- Don't help! - Over the gap.

0:01:35 > 0:01:38Got to be able to see up there. That's it.

0:01:38 > 0:01:40Today we're going to introduce you to a person who

0:01:40 > 0:01:43changed our view of the world, sorry, the UNIVERSE!

0:01:43 > 0:01:47Yes, she was one half of a brother-and-sister team that unlocked

0:01:47 > 0:01:50the secrets to deep, deep space.

0:01:50 > 0:01:53From building telescopes, to discovering comets -

0:01:53 > 0:01:54and even a new planet!

0:01:54 > 0:01:56- Right. Try and find her. - Oh, yeah.

0:01:56 > 0:01:58Ladies and gentlemen, we give you...

0:01:58 > 0:02:02- Have you found her yet? - No. Got her?

0:02:02 > 0:02:03Koo-eeee, boys!

0:02:03 > 0:02:04Caroline Herschel.

0:02:04 > 0:02:07Now, inspired by her genius, we're going to be creating our own

0:02:07 > 0:02:09genius idea later on in the show.

0:02:09 > 0:02:13And it's going to be an out of this world tribute to Herschel.

0:02:13 > 0:02:15It's coming straight for us!

0:02:15 > 0:02:17THEY SCREAM

0:02:17 > 0:02:20But first, let's find out how it all began...

0:02:22 > 0:02:26Today, powerful telescopes help scientists capture the most

0:02:26 > 0:02:29amazing images of the universe.

0:02:29 > 0:02:34But more than 250 years ago, people knew far less about space.

0:02:34 > 0:02:38Not every planet we know about now had been discovered.

0:02:38 > 0:02:42Astronomy was exciting, and full of mystery,

0:02:42 > 0:02:46and it was about to change the life of a young girl called Caroline.

0:02:50 > 0:02:53Caroline Herschel was born in Germany in 1750,

0:02:53 > 0:02:56into a life of pain and misery.

0:02:56 > 0:02:59Childhood diseases like typhus left her with scars,

0:02:59 > 0:03:01and stunted her growth.

0:03:02 > 0:03:05Because of her appearance, her parents thought that no-one

0:03:05 > 0:03:08would want to be with her for the rest of her life

0:03:08 > 0:03:12so they made the decision to keep her at home as the family maid.

0:03:13 > 0:03:17Have you finished yet? Get a move on.

0:03:18 > 0:03:20How awful.

0:03:20 > 0:03:22Eugh. What a stinker.

0:03:24 > 0:03:28But when she was 22 years old, she was bought to Bath in Somerset.

0:03:28 > 0:03:31Rescued by her favourite brother William,

0:03:31 > 0:03:33a professional musician and keen astronomer,

0:03:33 > 0:03:37together they would explore deep space!

0:03:38 > 0:03:42Can you believe that this house here would become Britain's

0:03:42 > 0:03:44version of the NASA headquarters?

0:03:45 > 0:03:46To tell us more...

0:03:48 > 0:03:49..it's genius helper,

0:03:49 > 0:03:53Joe Middleton from the Herschel Museum of Astronomy.

0:03:53 > 0:03:55- Hey, Joe. - Hi, Dom, very nice to meet you.

0:03:55 > 0:03:57Hi Joe, lovely to be in the Herschels' house,

0:03:57 > 0:03:58but what did they do here?

0:03:58 > 0:04:01This was the place where they actually designed,

0:04:01 > 0:04:04built and made their own home-made telescopes to actually

0:04:04 > 0:04:08stargaze and change what we know about the heavens.

0:04:08 > 0:04:11The Herschels wanted to see more clearly into deep space.

0:04:11 > 0:04:14So William designed, and together they hand-built the biggest

0:04:14 > 0:04:18and most hi-tech telescopes of the time.

0:04:18 > 0:04:22Their telescopes were the Rolls-Royces of all telescopes -

0:04:22 > 0:04:25they were the best that you could get.

0:04:25 > 0:04:27It's like finding the next door neighbour was

0:04:27 > 0:04:29making Formula 1 cars in the shed.

0:04:29 > 0:04:31They were making the best stuff around.

0:04:31 > 0:04:33What was Caroline's role in this house though?

0:04:33 > 0:04:36As an amateur, William decided to do his own surveys of the night

0:04:36 > 0:04:39sky and he needed Caroline's help, so she would do all

0:04:39 > 0:04:43the paperwork, record it and document for future generations.

0:04:45 > 0:04:49The Herschels' genius helped us map out the universe.

0:04:49 > 0:04:53They made their own telescopes to see further into deep space.

0:04:53 > 0:04:56William famously discovered the planet Uranus.

0:04:56 > 0:04:59And his astronomer sister Caroline became the first woman to

0:04:59 > 0:05:03spot one of the most mysterious objects in our solar system.

0:05:03 > 0:05:04What's that?!

0:05:04 > 0:05:07- A comet.- Thank you!- And not just one,

0:05:07 > 0:05:10she went on to discover eight of them! Genius.

0:05:14 > 0:05:16What's so important about discovering comets?

0:05:16 > 0:05:19Comets were just one of the real dynamic things

0:05:19 > 0:05:20to see in the night sky.

0:05:20 > 0:05:22I remember when I was a kid, I saw Halley's Comet.

0:05:22 > 0:05:25- That's a famous one, isn't it?- Yeah, and so to stake claim that you

0:05:25 > 0:05:29discovered a new comet would just make you an instant celebrity.

0:05:29 > 0:05:31Ooh, ooh, ooh - cameras!

0:05:31 > 0:05:33Caroline held the world record for most comets

0:05:33 > 0:05:37discovered by a woman for almost 200 years.

0:05:37 > 0:05:40She also became the first female scientist in Britain to be

0:05:40 > 0:05:42paid for her work.

0:05:42 > 0:05:45- It says the tail of the comet... - Very neat handwriting, isn't it?

0:05:45 > 0:05:47- Looks like she's had a ruler. - Read it, read it, read it...

0:05:47 > 0:05:50"The most brilliant phenomenon that accompanied a comet is

0:05:50 > 0:05:52"the stream of light which we call the tail."

0:05:52 > 0:05:57Her handwriting is actually meticulous. It is so, so perfect.

0:05:57 > 0:05:58That is beautiful.

0:05:58 > 0:06:01Yeah, yeah, I have nice handwriting -

0:06:01 > 0:06:03what about the astronomy?

0:06:03 > 0:06:05We want to discover our own passion for astronomy,

0:06:05 > 0:06:09so we've come here - to a house on the Wirral!

0:06:09 > 0:06:11I LOVE the Wirral.

0:06:11 > 0:06:14The Wirral, the north west of England,

0:06:14 > 0:06:16location for the M53 motorway.

0:06:16 > 0:06:20and childhood home to Bond actor Daniel Craig.

0:06:20 > 0:06:23But we're not here to spot Hollywood superstars, no,

0:06:23 > 0:06:26we're here to explore the wonders of the universe.

0:06:26 > 0:06:29Yep, we're going stargazing!

0:06:31 > 0:06:34With genius helper Brendan Martin,

0:06:34 > 0:06:38and his mates Dave and Geoff, from the Liverpool Astronomical Society.

0:06:38 > 0:06:41Just like the Herschels, they build their own telescopes.

0:06:46 > 0:06:47The proof is in the back garden.

0:06:47 > 0:06:50It's full of home-built observatories.

0:06:52 > 0:06:54Brendan and the guys are letting us

0:06:54 > 0:06:57borrow one of their precious handmade telescopes.

0:06:57 > 0:07:00It works in a similar way to the Herschels' telescopes,

0:07:00 > 0:07:03and took three years to build.

0:07:03 > 0:07:05How does this telescope work then?

0:07:05 > 0:07:08The light comes down, hits this mirror,

0:07:08 > 0:07:11then it's reflected back up to this secondary mirror, which is

0:07:11 > 0:07:16at a 45 degree angle and that sends the light out to the eyepiece.

0:07:16 > 0:07:18Why is amateur astronomy so important?

0:07:18 > 0:07:23We search for supernova, the death of a massive star.

0:07:23 > 0:07:26The professionals who used to do this don't have the time any more.

0:07:26 > 0:07:29So what happens is the amateurs discover them,

0:07:29 > 0:07:31and then they can let the professionals know,

0:07:31 > 0:07:33and then they can turn their telescopes onto them.

0:07:33 > 0:07:36So you're like the professionals' secret spy unit.

0:07:37 > 0:07:41There are amateur astronomers all over the world just like Brendan.

0:07:41 > 0:07:45Using modern telescopes, they capture amazing images,

0:07:45 > 0:07:48often making new discoveries of their own.

0:07:49 > 0:07:52Ah, the M45 star cluster. Mmm. Yes...

0:07:54 > 0:07:55So you built this with your fair hands

0:07:55 > 0:07:57and you're going to trust us with it?

0:07:57 > 0:07:59I'm going to let you look through it.

0:07:59 > 0:08:00Yeah, and that's it.

0:08:00 > 0:08:04Don't let us anywhere near that very lovely mirror.

0:08:05 > 0:08:08And while we prepare for a night of stargazing,

0:08:08 > 0:08:12here are some top facts about the solar system.

0:08:15 > 0:08:17It's the genius top five.

0:08:18 > 0:08:21At five - more than 100 spacecraft have been

0:08:21 > 0:08:23launched to the moon.

0:08:23 > 0:08:25It's still the only place in space that humans have landed on,

0:08:25 > 0:08:28stepped onto, and explored.

0:08:28 > 0:08:30- SPACEMAN:- I'm king of the moon!

0:08:30 > 0:08:34Four - the furthest galaxy detected from earth is about 30 billion

0:08:34 > 0:08:35light years away,

0:08:35 > 0:08:39And goes by the catchy name of z8 GND 5296!

0:08:41 > 0:08:45Three - Jupiter's Great Red Spot is a gigantic storm -

0:08:45 > 0:08:47about the size of up to three planet Earths,

0:08:47 > 0:08:51and it's been raging for hundreds of years.

0:08:52 > 0:08:54At two - More than 200 thousand people have

0:08:54 > 0:08:57applied for a one-way ticket to Mars.

0:08:57 > 0:09:00A Dutch engineer's been asking for volunteers to set up a human

0:09:00 > 0:09:01base on the planet.

0:09:01 > 0:09:05Problem is, if you change your mind, there's no way back!

0:09:05 > 0:09:07And at one - apart from the eight planets

0:09:07 > 0:09:09in our solar system,

0:09:09 > 0:09:12there are more than half a million registered minor planets -

0:09:12 > 0:09:1317 of them called Dave...

0:09:15 > 0:09:16..and one called Dick.

0:09:16 > 0:09:19I always said he was on another planet.

0:09:19 > 0:09:22Right, so because it's night-time we've of course,

0:09:22 > 0:09:24as you've probably realised, got night vision.

0:09:24 > 0:09:27Let's have a look at what we can see.

0:09:27 > 0:09:30- If you want to have a look at that. - You've spotted something already?

0:09:30 > 0:09:32- Yep. It's a globular cluster. - A what?

0:09:32 > 0:09:33Globular cluster.

0:09:33 > 0:09:35Global... Globeler... I can't even say it.

0:09:35 > 0:09:37What's a glob-lar cluster?

0:09:37 > 0:09:38DOM LAUGHS

0:09:38 > 0:09:42It's a collection of stars, about 33,000 light years away.

0:09:42 > 0:09:4833... It's incomprehensible to think about how far away that is.

0:09:50 > 0:09:54The M13 cluster is home to more than 100,000 stars,

0:09:54 > 0:09:58so huge it spans 150 light years -

0:09:58 > 0:10:01each light year equal to around 6 trillion miles!

0:10:03 > 0:10:05Amazing. Come and have a look.

0:10:05 > 0:10:07Look, it's there, look.

0:10:07 > 0:10:08In the middle.

0:10:10 > 0:10:12And how big are each one of these stars?

0:10:12 > 0:10:14- They vary in size. - What's the biggest?

0:10:14 > 0:10:18Um, probably around 20 solar masses, possibly more.

0:10:18 > 0:10:20So the size of...? Is that compared to our sun?

0:10:20 > 0:10:22About 20 times the size of the sun.

0:10:22 > 0:10:24What?! Wow.

0:10:24 > 0:10:26We're looking at some stars and some of them

0:10:26 > 0:10:29are 20 times the size of the sun.

0:10:29 > 0:10:31Yeah, but get this right in your head...

0:10:31 > 0:10:34- The sun is how many times bigger than the earth?- A million.

0:10:34 > 0:10:35THEY LAUGH

0:10:35 > 0:10:38But what is it? Hang on... What is it?

0:10:38 > 0:10:44It's a massive ball of fire - just floating around in space!

0:10:45 > 0:10:47What's it doing there?

0:10:47 > 0:10:50What's it think it's doing?

0:10:50 > 0:10:53It's making me feel quite uncomfortable.

0:10:53 > 0:10:56Very hard to get your head around the universe, isn't it?

0:10:56 > 0:10:57It is, it can be.

0:10:57 > 0:11:00How important was the work the Herschels were doing at the time?

0:11:00 > 0:11:02Well, it was very important, because they were actually

0:11:02 > 0:11:08cataloguing everything they saw and marking its location in the sky,

0:11:08 > 0:11:11to make it easier for other astronomers around the world.

0:11:12 > 0:11:15I think we can now realise why the Herschels were getting

0:11:15 > 0:11:18so excited about what's up there.

0:11:18 > 0:11:19What is up there?

0:11:22 > 0:11:26We've been blown away by seeing the M13 globular cluster,

0:11:26 > 0:11:30but Caroline was searching for something even more spectacular -

0:11:30 > 0:11:32comets!

0:11:32 > 0:11:34Which leads us to one burning question...

0:11:34 > 0:11:37What are comets?

0:11:37 > 0:11:39- I don't know.- Fran?

0:11:40 > 0:11:43This is Fran, she just loves experimenting...

0:11:45 > 0:11:48..to help explain the ideas of our geniuses.

0:11:48 > 0:11:52And she's sure to pop up just when you really need her.

0:11:52 > 0:11:55Fran, quite a big question here - what is a comet?

0:11:55 > 0:12:00OK, well, a comet is like a cosmic snowball that zooms around the sun.

0:12:00 > 0:12:03It orbits around it - sometimes going really close to the sun

0:12:03 > 0:12:05and sometimes far away.

0:12:05 > 0:12:09Comets are made from the leftover stuff from the solar system

0:12:09 > 0:12:11after the planets and the moons and the sun formed.

0:12:11 > 0:12:14So like, when someone's building a house they've got

0:12:14 > 0:12:16a pile of leftover bricks?

0:12:16 > 0:12:18Yes. That that is a comet.

0:12:18 > 0:12:20But I thought the best way to show you in detail what it's

0:12:20 > 0:12:22made from is to make one.

0:12:22 > 0:12:24So, Dick, can you pour that water into here?

0:12:24 > 0:12:27This is where I'm going to make my comet.

0:12:27 > 0:12:30These are smelling salts. Do you know about smelling salts?

0:12:30 > 0:12:32It's something to wake you up, is it?

0:12:32 > 0:12:35- Yeah, have a sniff...- Eugh.

0:12:35 > 0:12:37Shake that ammonia in.

0:12:37 > 0:12:40A comet can be quite rocky, so we've got some sand there to represent

0:12:40 > 0:12:44those rocks and minerals right inside that comet's core.

0:12:44 > 0:12:46Now, the exciting thing about comets is

0:12:46 > 0:12:49they contain what are known as organic molecules.

0:12:49 > 0:12:52Now, organic molecules are molecules that contain an element

0:12:52 > 0:12:56known as carbon, and soy sauce, surprisingly,

0:12:56 > 0:12:58has a lot of organic molecules.

0:12:58 > 0:13:00So can you give a good dollop?

0:13:00 > 0:13:03- How much? - A good shake, let's say.

0:13:03 > 0:13:06The other thing that comets contain are amino acids,

0:13:06 > 0:13:10and amino acids make up proteins, so we've got some amino acids here.

0:13:10 > 0:13:13So give a good sprinkle of those into our comet.

0:13:13 > 0:13:14You might see on adverts that

0:13:14 > 0:13:17shampoo contains amino acids, apparently,

0:13:17 > 0:13:19so we've got some shampoo here.

0:13:19 > 0:13:22My turn! Get off!

0:13:22 > 0:13:24That's it - that'll do, that'll do.

0:13:24 > 0:13:27This last ingredient will freeze it down quite quickly into what

0:13:27 > 0:13:30is hopefully a dirty snowball.

0:13:30 > 0:13:32But it's pretty dangerous, so we need to pop our goggles on,

0:13:32 > 0:13:35so put your goggles on your face, and your gloves on.

0:13:38 > 0:13:42This is dry ice, which is frozen carbon dioxide.

0:13:42 > 0:13:45This is at minus 80 degrees Celsius.

0:13:45 > 0:13:48Hopefully, when we put it in here,

0:13:48 > 0:13:50it will cause the water to bubble away a little bit.

0:13:50 > 0:13:52- Right, OK.- Just like...

0:13:52 > 0:13:56- Harry Potter stylee!- Here we go...

0:13:56 > 0:13:59- Mmmm. Lovely bubbly. - Now, what I want to do is...

0:14:02 > 0:14:04- All right, Fran!- Can you see it?

0:14:04 > 0:14:06I can see that.

0:14:06 > 0:14:08I'm trying to squeeze all the ingredients together.

0:14:08 > 0:14:12So just that bit of dry ice will freeze the contents of that bag?

0:14:12 > 0:14:13Hopefully.

0:14:17 > 0:14:21- I think that might be ready. - Have we got a dirty snowball?

0:14:21 > 0:14:22Hopefully.

0:14:22 > 0:14:25Let's have a look! Ahhhh! It's a comet!

0:14:26 > 0:14:28Now, this is a comets core.

0:14:28 > 0:14:31Most of the pictures you might have seen of a comet have that

0:14:31 > 0:14:34sort of rocky bit in the middle then that beautiful tail coming

0:14:34 > 0:14:35out from behind it.

0:14:35 > 0:14:39And that happens when they go near the sun, and they're heated up by

0:14:39 > 0:14:43the sun and so all of the ice that's in the comet's core is turned into a

0:14:43 > 0:14:47gas, so that's all the gas trailing behind the comet that you see.

0:14:47 > 0:14:51- Wow.- And can you see just there? Can you see that gas coming out?

0:14:51 > 0:14:53That's like our comet's tail.

0:14:53 > 0:14:55- Can I hold it? - Of course you can.

0:14:55 > 0:14:57Do you know what this reminds me of, Fran?

0:14:57 > 0:15:00- Er, I don't think I want to know. - Your brain.

0:15:03 > 0:15:07Comets travel in a big loop - from the icy edges of the solar

0:15:07 > 0:15:09system, round the sun and back again.

0:15:09 > 0:15:12When they heat up they release dust and gases -

0:15:12 > 0:15:15the comet tail Herschel wrote about!

0:15:15 > 0:15:18But you have to be patient to spot one.

0:15:18 > 0:15:23Some, like Halley's Comet, pass earth once every 76 years.

0:15:23 > 0:15:26Others take thousands of years.

0:15:26 > 0:15:30We need to know more about these dirty great snowballs.

0:15:30 > 0:15:33We've come to the Royal Observatory in London to meet...

0:15:34 > 0:15:37..genius helper and astronomer Liz Roche.

0:15:38 > 0:15:40- Hey Liz, how are you doing?- I'm good.

0:15:40 > 0:15:43We've had the pleasure of making our own comet,

0:15:43 > 0:15:46which was really interesting, but we need to know more about them.

0:15:46 > 0:15:49Do you have one here in this amazing place that we can touch?

0:15:49 > 0:15:50- Or a bit of one?- A bit of one...

0:15:50 > 0:15:53That would be brilliant, but unfortunately, no, we can't because

0:15:53 > 0:15:57if comets ever do come to earth they kind of just evaporate and there's

0:15:57 > 0:16:01nothing left to look at apart from the big hole that they left behind.

0:16:01 > 0:16:03But there are other things to look at that were around at the time

0:16:03 > 0:16:06when our solar system was forming that we can touch, like this one.

0:16:06 > 0:16:08You're not talking about that massive

0:16:08 > 0:16:10hunk of rock right in front of you, are you?

0:16:10 > 0:16:13- I am. Yes.- What is this? - So this is a meteorite -

0:16:13 > 0:16:16a chunk of asteroid that probably broke off

0:16:16 > 0:16:19and then as it comes through our atmosphere we call it a meteor,

0:16:19 > 0:16:23and if it lands to earth we call it a meteorite.

0:16:23 > 0:16:26And how old are we talking for these comets and asteroids?

0:16:26 > 0:16:28As old as our solar system.

0:16:28 > 0:16:30In fact even older than our solar system

0:16:30 > 0:16:32because they're left over from when it formed.

0:16:32 > 0:16:354.5 billion years old.

0:16:35 > 0:16:37This is the oldest thing you will ever touch.

0:16:37 > 0:16:38Unbelievable.

0:16:38 > 0:16:42What kind of damage could a comet do if it hit the earth?

0:16:42 > 0:16:44You've only got to look at something like the moon to

0:16:44 > 0:16:48really see the kind of damage that can be done by space rocks

0:16:48 > 0:16:51hitting into something, cos our moon is covered in craters.

0:16:51 > 0:16:53And that's how that was done.

0:16:53 > 0:16:55Wow, right, I never knew that.

0:16:55 > 0:16:58They come from lots of different things in space, like asteroids

0:16:58 > 0:17:01and meteors and possibly comets as well -

0:17:01 > 0:17:03so all sorts of things just crashing into it.

0:17:03 > 0:17:05So the moon gets a fair old battering, doesn't it?

0:17:05 > 0:17:06Has done over the years.

0:17:08 > 0:17:11If that's the kind of damage comets can do - you would NOT want

0:17:11 > 0:17:13to get in the way of one!

0:17:13 > 0:17:15But how likely is it they could hit us on earth?

0:17:16 > 0:17:19To get the lowdown we're meeting...

0:17:21 > 0:17:25..genius helper Dr Gareth Collins, from Imperial College London.

0:17:25 > 0:17:28He knows all about the damage caused by objects hitting us

0:17:28 > 0:17:29from outer space.

0:17:31 > 0:17:34- Hi, Gareth.- Nice to meet you.

0:17:34 > 0:17:37How often do smaller objects actually penetrate

0:17:37 > 0:17:39the earth's atmosphere?

0:17:39 > 0:17:42Well, we're hit by pebble sized things all the time.

0:17:42 > 0:17:46In fact, if it's a clear night and you're lucky,

0:17:46 > 0:17:48you'll probably see a shooting star, which is

0:17:48 > 0:17:51- something about that size burning up in the atmosphere.- No way!

0:17:51 > 0:17:54OK, OK, so, how long before we get an asteroid or comet

0:17:54 > 0:17:59- the size of a city? - That is a truly rare event.

0:17:59 > 0:18:03That probably only happens every once in 100 million years.

0:18:03 > 0:18:04Thank goodness for that.

0:18:04 > 0:18:07Looks like we'll all be safe for a good few million years yet.

0:18:07 > 0:18:09Great idea for a science fiction movie though!

0:18:09 > 0:18:11When was the last one?

0:18:11 > 0:18:1265 million years ago.

0:18:12 > 0:18:14And what kind of damage would that do?

0:18:14 > 0:18:17When they slam into a planet it's like a huge explosion.

0:18:17 > 0:18:19Comets are travelling incredibly fast.

0:18:19 > 0:18:21Probably about 40km per second.

0:18:21 > 0:18:24- What's that in miles an hour? - That's 100,000 miles per hour.

0:18:24 > 0:18:27100,000 miles per hour!

0:18:27 > 0:18:29Or 200 times the speed of a jumbo jet.

0:18:29 > 0:18:32Wow! Have you got some kind of experiment that you can

0:18:32 > 0:18:36show us that will give us an idea of the damage that gets done by one?

0:18:36 > 0:18:38We can't get up to 40km a second,

0:18:38 > 0:18:42but what we can do is fire this cannon.

0:18:42 > 0:18:44To safely provide the firepower, we've enlisted

0:18:44 > 0:18:49the help of Worcester Norton Shooting Club, and their cannons.

0:18:49 > 0:18:52Here's Bob and Trevor, our mini-cannon experts.

0:18:52 > 0:18:55OK, boys, you think you can put a crater into that clay there?

0:18:55 > 0:18:58- With that? - Well, yes, we think so, yes.

0:18:58 > 0:19:00If we use the proper ammunition for it, which is

0:19:00 > 0:19:03like a lead ball, it'll put a hole through that.

0:19:03 > 0:19:05What are you going to use, then? What's the ammunition?

0:19:05 > 0:19:09We've raided the bushes, and we're using rosehips.

0:19:09 > 0:19:10Eh?

0:19:10 > 0:19:14So that is our comet. A biodegradable comet.

0:19:14 > 0:19:16Actually, it's a great representation of a comet.

0:19:16 > 0:19:17It's low density,

0:19:17 > 0:19:20and just like a comet it's going to explode on impact.

0:19:20 > 0:19:23Right, Bob and Trevor, do your stuff!

0:19:24 > 0:19:28The cannon is primed with a small amount of gunpowder.

0:19:28 > 0:19:30Look at that it's a perfect fit.

0:19:30 > 0:19:33Instead of a lead ball, we're using a rosehip,

0:19:33 > 0:19:36which should break up like a comet on impact.

0:19:39 > 0:19:42All you need is an absolute idiot who's ready to light the thing.

0:19:43 > 0:19:45He looks at me!

0:19:48 > 0:19:50Fire in the hole!

0:19:50 > 0:19:52BANG Yeah, look at that!

0:19:52 > 0:19:56- Yeah, look at that!- Beauty!

0:19:56 > 0:19:58Yeah, this is great. We can see

0:19:58 > 0:20:00some quite characteristic features of craters here.

0:20:00 > 0:20:05We have the impacter completely broken up,

0:20:05 > 0:20:07a raised rim of material thrown out around the crater...

0:20:07 > 0:20:11This is something you see on a lot of lunar movies,

0:20:11 > 0:20:13and all the footage from the original moon landing.

0:20:13 > 0:20:15It's very characteristic of impact craters.

0:20:17 > 0:20:19- That's great. Can we do it again? - Can we do it again?

0:20:19 > 0:20:22BANG Yeah! Look at that!

0:20:22 > 0:20:24So, Gareth, why is the crater that we've just made

0:20:24 > 0:20:26so much smaller than the first?

0:20:26 > 0:20:31Speed. That time, the rosehip registered only 99 feet per second.

0:20:31 > 0:20:34- And what was the last one?- 400.

0:20:34 > 0:20:38The first rosehip hit the clay at around 120 metres per second.

0:20:38 > 0:20:41The second one was much slower, at 30 metres per second.

0:20:41 > 0:20:43So it made less impact.

0:20:43 > 0:20:46So the faster they're travelling the bigger the impact,

0:20:46 > 0:20:47- the bigger the crater. - Yes.

0:20:47 > 0:20:49So how can we now do the next shot

0:20:49 > 0:20:52and make sure we've got a bigger crater than the first?

0:20:52 > 0:20:55- We need more speed. - How do we make it go faster guys?

0:20:55 > 0:20:57More powder!

0:20:57 > 0:21:00Bob's doubling the amount of firepower in our cannon to

0:21:00 > 0:21:02increase the speed of the rosehip.

0:21:02 > 0:21:04Our final hit should be the biggest yet.

0:21:06 > 0:21:08BANG Come on!

0:21:08 > 0:21:10- Yeah!- Look at the size of that!

0:21:13 > 0:21:14How fast was that going?

0:21:14 > 0:21:16That was about 240 metres per second.

0:21:16 > 0:21:18That was double the speed of the first one!

0:21:18 > 0:21:20Which is why it's twice as big.

0:21:20 > 0:21:21Twice as big.

0:21:21 > 0:21:23So it's not the size of the comet that matters,

0:21:23 > 0:21:24it's all about the speed -

0:21:24 > 0:21:26because these rosehips were all the same size.

0:21:26 > 0:21:28Absolutely. It's all about speed.

0:21:28 > 0:21:30Our very own craters!

0:21:30 > 0:21:33The kind of holes a speeding comet might leave behind.

0:21:33 > 0:21:37Cracking craters, boys.

0:21:37 > 0:21:40Inspired by the Herschels, we've discovered our own

0:21:40 > 0:21:43passion for astronomy and the Universe!

0:21:46 > 0:21:49We've investigated Caroline's world of comets...

0:21:50 > 0:21:52..and seen the craters they can cause!

0:21:53 > 0:21:55And now, inspired by Caroline's comets,

0:21:55 > 0:21:59we're going to reveal the genius idea.

0:21:59 > 0:22:03Right, here goes - we're going to make our own comet action movie.

0:22:04 > 0:22:07Our genius idea - to star in our own film,

0:22:07 > 0:22:11in which we attempt to escape a comet heading straight for us.

0:22:11 > 0:22:12Our challenge -

0:22:12 > 0:22:16to use what we've discovered to make it look as realistic as possible.

0:22:16 > 0:22:19Our problem - we've never directed a film before.

0:22:19 > 0:22:22So instead of genius, it could be absolute rubbish!

0:22:25 > 0:22:28To provide the special effects, it's genius helper Mark Turner.

0:22:28 > 0:22:30Standing by.

0:22:30 > 0:22:32In the past he's helped us do this...

0:22:35 > 0:22:38So a comet crater should be no problem!

0:22:38 > 0:22:41- Hey, Mark. Good to see you again. - Hello.- Friend of the show.

0:22:41 > 0:22:43Right, today we are making an action movie.

0:22:43 > 0:22:46This is our storyboard and we need you for this part, a crater.

0:22:46 > 0:22:50- Fantastic.- We've been studying craters, we need a fairly big hole,

0:22:50 > 0:22:52kind of slopes over at the side, and lots of debris.

0:22:52 > 0:22:54- Can you do that?- We can do that.

0:22:54 > 0:22:56- Can I show you how the special effects people do it?- Yeah, go on.

0:22:56 > 0:22:59We take a mortar like this. We add...

0:23:00 > 0:23:01Compost.

0:23:01 > 0:23:05A bit of this vermiculite, cork to simulate stones

0:23:05 > 0:23:06and the rubble in there.

0:23:06 > 0:23:09So we've got a soft, spongy mixture that's going to really fly

0:23:09 > 0:23:12high into the air, but what's actually going to be sending it up?

0:23:12 > 0:23:14I think we should use gunpowder.

0:23:14 > 0:23:17Ha-ha! Look at that!

0:23:17 > 0:23:18Two!

0:23:18 > 0:23:20I reckon about a kilo of gunpowder should do it.

0:23:20 > 0:23:22It's going to be one mighty crater.

0:23:25 > 0:23:30Comets disintegrate on impact, so our explosive effect must be

0:23:30 > 0:23:32big enough to leave an empty hole behind.

0:23:34 > 0:23:36While you're covering this over

0:23:36 > 0:23:38we're going to continue with our movie.

0:23:38 > 0:23:39See you in a bit.

0:23:39 > 0:23:43Let's make a bit of a kind of city street here,

0:23:43 > 0:23:46- a little bungalow, look. - Very nice.

0:23:46 > 0:23:48Where are you going?

0:23:49 > 0:23:51It looks like a comet!

0:23:52 > 0:23:54Oh, look a telescope - woohoo!

0:23:55 > 0:23:58We just need one more thing for this movie to be complete.

0:23:58 > 0:24:00A little flame.

0:24:01 > 0:24:03All right, Mark!

0:24:05 > 0:24:09To recreate a glowing comet tail, Mark's built a genius contraption,

0:24:09 > 0:24:13using fishing wire and a wooden ball covered in flaming cotton felt.

0:24:14 > 0:24:16Yeah, nice.

0:24:16 > 0:24:17Look at that! Brilliant!

0:24:17 > 0:24:22Mark's an expert - so don't try this at home.

0:24:22 > 0:24:24We've just one more explosive scene to film

0:24:24 > 0:24:27in our Herschel-inspired action movie.

0:24:27 > 0:24:30But first, here's another tale about comets.

0:24:30 > 0:24:33It's the not so genius idea....

0:24:33 > 0:24:37The Deep Impact Spacecraft has spent almost nine years chasing comets,

0:24:37 > 0:24:40gathering incredible information on how they're formed.

0:24:40 > 0:24:43Genius, huh?

0:24:43 > 0:24:45Er, no, because it's gone missing!

0:24:45 > 0:24:47Deep Impact's thought to have lost control,

0:24:47 > 0:24:49pointing its antenna in the wrong direction.

0:24:49 > 0:24:51Now it's a write off,

0:24:51 > 0:24:54and NASA's given up trying to make contact.

0:24:54 > 0:24:56Well, gosh, golly-darn it!

0:24:58 > 0:24:59So our movie is complete.

0:24:59 > 0:25:02Just one more scene to film now, which is the comet

0:25:02 > 0:25:05hitting our model city, leaving a massive great crater.

0:25:05 > 0:25:07Mmm. Ear defenders on. And you, Caroline.

0:25:07 > 0:25:09Right, Mark, push the button.

0:25:09 > 0:25:13In five, four, three, two, one!

0:25:13 > 0:25:14Stop!

0:25:14 > 0:25:18Spoiler alert! You'll just have to wait.

0:25:18 > 0:25:22We've been on an brain-boggling journey with the Herschels,

0:25:22 > 0:25:26who helped unlock deep space.

0:25:26 > 0:25:29We discovered how Caroline Herschel found new comets -

0:25:29 > 0:25:32left over from the creation of the solar system.

0:25:32 > 0:25:34And inspired by the craters they could cause,

0:25:34 > 0:25:37we've filmed our own comet action movie.

0:25:37 > 0:25:39And as we say in the movies that's a wrap.

0:25:39 > 0:25:42Caroline Herschel, you are an Absolute Genius,

0:25:42 > 0:25:43and our film is in honour of you.

0:25:43 > 0:25:45It's called Caroline's Comet.

0:25:45 > 0:25:48Why, thank you, boys.

0:25:48 > 0:25:49Enjoy the movie.

0:25:59 > 0:26:03- Where is everybody?- I don't know.

0:26:09 > 0:26:11I think I can see a comet.

0:26:11 > 0:26:13It's all right, it's miles away!

0:26:13 > 0:26:16- No...!- That's clever, the way it's getting bigger and bigger.

0:26:16 > 0:26:20Yeah. It's coming straight for us!

0:26:20 > 0:26:22THEY SCREAM

0:26:26 > 0:26:27Quick, get in the car!

0:26:30 > 0:26:32Right, go, go, go!

0:26:32 > 0:26:35Go, go, go, go, go, go, go!

0:26:37 > 0:26:38Seat belt.

0:26:39 > 0:26:42- Floor it, Dicky! - ROCK MUSIC

0:26:49 > 0:26:50We've got to do something!

0:26:52 > 0:26:55Ah. Boxes!

0:26:55 > 0:26:56DOM SCREAMS

0:26:57 > 0:27:00- Let's change the music. - COUNTRY AND WESTERN MUSIC

0:27:02 > 0:27:03That hasn't helped!

0:27:03 > 0:27:05The road's closed - handbrake turn!

0:27:07 > 0:27:10ROCK MUSIC

0:27:11 > 0:27:13THEY SCREAM IN SLOWMO

0:27:19 > 0:27:22THEY SCREAM

0:27:34 > 0:27:36- I tell you what - that was close.- Yeah!

0:27:36 > 0:27:39Oh, I've spotted another one!

0:27:39 > 0:27:41- BANG! - Now roll those credits!

0:27:45 > 0:27:47Aaaah!

0:27:47 > 0:27:50Eurgh! It smacked me in the face!

0:27:50 > 0:27:51- Dom's!- Oh, no!

0:27:55 > 0:27:58- What are you doing?! - Let me get it straight!

0:27:58 > 0:27:59Ooh!

0:27:59 > 0:28:01What's all that? What's all the black stuff?

0:28:01 > 0:28:03- Hey-hey!- Aaaah!

0:28:06 > 0:28:08Aieeeee!