Hello. Good evening. Welcome to a very special Question Time edition
of The Sky At Night.
We're here at the British Science Festival
here at De Montfort University.
We have a live studio audience!
APPLAUSE
Welcome to The Sky At Night.
APPLAUSE
Hey. Thank you very much.
Welcome to The Sky At Night - Question Time.
Hey, look, look. Time flies by when you're having fun.
This is the 66th year of The Sky At Night,
which means if you've been paying attention, people,
that is the - let me get this right - 825th episode,
not including... Specials, archives...
..compilation shows, that kind of thing.
The whole show started in 1957, which of course, was the beginning,
very much of the space age with the launch of Sputnik,
the very first artificial satellite launched by the Soviet Union.
Since then we've learnt a little bit more about the cosmos.
Hopefully we're going to learn
a little bit more about the cosmos tonight.
And whilst some of those very, very early programmes
sadly have been lost in the space-time continuum,
we've put together a little compilation to show you
what we've been up to for the last 60 years or so.
You know, if I'd come on the air in 1957 when we did the first
of these Sky At Night programmes and said that within five years,
I'd be showing you pictures of the first man to go
round the Earth in orbit in a spaceship,
well, I think you'd have regarded me as mad.
We've just had some amazing photographs sent back
by the American probe to Mars, Mariner 6.
You can see there some of the dark areas, which may be vegetation.
Do you think that these dark areas are due to anything organic?
What do you think about it? Primitive life, there may be.
I don't even think so. Intelligent life, certainly not.
So, in other words, you rather think
that Mars is a dead planet? Absolutely dead as a dodo.
I suppose one of these things, we're going to find out fairly soon.
Do you think, from your knowledge of the Moon, having been there,
that it is going to be possible, in the foreseeable future,
to set up scientific bases there or anything like a large scale?
Oh, I'm quite certain that we'll have such bases
in our lifetime.
If we had a gamma-ray burst in our galaxy,
it might be pretty dangerous.
It could be very dangerous indeed.
Supernovae, of course, can be dangerous if they were
to go off near the Earth,
but a gamma-ray burst is that much more powerful that we believe
it could be detrimental to life on Earth.
Just an hour ago, it was completely cloudy, but the skies have cleared
and behind me, you can see the young crescent Moon
and nearby, the planet Mercury.
A great shot for our astrophotographers.
Well, the clouds are coming and going,
but I have managed to find Mercury.
It's right in the centre of my field of view.
It's really satisfying to find a planet in the daytime sky.
The data Bepi sends back could also have ramifications
for not only Mercury, but the whole solar system.
It's going to be absolutely transformative for our understanding
of the formation and the evolution of the entire planetary system.
So, Maggie, you're an astronomer.
What are you doing working in a satellite company?
Well, I love astronomy, and that is sort of where I started.
But I make instrumentation,
and instrumentation can be used in astronomy for ground-based,
but also up in space.
So one of the satellites I'm working on at the moment
is the James Webb Space Telescope - replacement for Hubble
probably going up about 2013,
and that will give us a whole new vista on space.
The JWST is an incredible feat of engineering,
and I'm immensely proud to be one of the 10,000 scientists
that worked on it.
The amount of new tech we kitted the telescope out with
is absolutely mind-blowing.
Whatever happens and whatever's discovered,
we'll be here to report it for you.
Oh, it's... You're all so young!
It's like time has stood still!
APPLAUSE
CHUCKLING
Hey, listen, it's great to be doing this show again.
It's lovely to be in Leicester.
Leicester, of course, home of the National Space Centre.
Home of the new Space Park.
Home of...
..kings, car parks,
genetic fingerprinting, all kinds of different things.
But, of course, probably most importantly,
it's the home of the crisp - or a particular brand of crisp.
So in honour of that, I thought, as we introduce ourselves
as panellists, you can tell me your top crisp flavour
and where in the universe you would like to eat your crisp.
So we'll start with Chris and we'll go around.
OK. Don't let us down. Sure.
I'm Chris Lintott, I'm one of the presenters.
I care about galaxies and occasionally asteroids
and various things.
I'm a simple man - salt and vinegar crisps,
and I'd like to eat them amongst the wonderful flavours of
the Orion Nebula, which has all sorts of different chemicals.
I'm a bit worried about salt vinegar because for me,
salt and vinegar is blue,
and in this particular brand of crisp, salt and vinegar is green.
Well, the packet... The packet's receding from you
at the right velocity... Sorry. Too early? Is it? Too early?
OK. Yeah, There's a science explanation for that. Good.
Suzie? Yeah, I'm Suzie and I'm a planetary scientist.
I'm interested in magnetic fields of planets
and how they interact with the Sun,
and particularly the Earth and Mercury.
My favourite crisp...
I think this is going to be the most popular one of all, actually.
My favourite crisp is pickled onion Monster Munch,
and I would like to eat them on the International Space Station
because they're full of crumbs,
it would be the most annoying thing you could possibly eat. The smell!
The smell of it would be... Smells amazing! It would be a disaster.
I love... It would linger. ..a picked onion Monster Munch.
We all love pickled... It crosses generations,
the pickled onion Monster Munch.
Yeah. Maggie, what about you? My name is Maggie Aderin-Pocock.
I'm a space scientist and a science communicator. Correct.
Getting onto the crisps...
CHUCKLING
So I think I'd go for cheese and onion -
mainly because I have a dairy allergy now.
Oh, right. And so I used to love cheese and onion,
they were my favourite flavour, but I can't eat them any more.
Oh, no! But I have the memory.
Just onion. Just an onion. An onion.
Pickled onion Monster Munch! No, no, see, you're wrong about that.
That's horrible.
And as to where I would eat them,
I think I would like to be on the cusp, on the event horizon
of a supermassive black hole.
Crikey!
For each crunch, I'd be...
LAUGHTER DROWNS SPEECH
Cos I love living a life of excitement.
Crisp spaghettification...
Yes! ..I think would happen. I'd love to see that.
Nial.
Yes, I am Nial Tanvir.
I work at the University of Leicester and I study things
that go bang in galaxies far, far away.
So that's my thing. OK.
I'm even simpler than Chris.
I really just like ready salted crisps.
I'm afraid none of those artificial flavours for me.
And I guess if I have to eat them anywhere interesting,
I'll go for the restaurant at the end of the universe,
which, for people of a certain age, will mean something
and the other people can go and look it up.
I like just ready salted as well.
I used to like it when you get the little blue packets
in them olden days because that was always quite exciting. So that's OK.
Right. And, finally, Pete!
At the end.
Yes, my name's Pete Lawrence.
I'm an astronomer and a presenter on the show
and my favourite flavour of crisps,
which I'm probably not allowed to say,
so I'll... I'll code it somewhere.
The yeast extract flavour crisps are my favourite.
LAUGHTER
And I would like to eat them
on the far side of the Moon
because I'll be able to get some peace and quiet
and look up at the night sky without being bothered.
Exactly. And half the universe will hate you for it.
Why?
Because it's yeast... They don't like the yeast flavoured crisps.
Yes, they do! At least half of them. Do they? They do.
They love them, yes. Could spend an hour doing this.
Hey, listen, we've got a lot of questions to get through.
Because we've got so many and it's only an hour show,
we're reduced to just yes or no answers.
CHUCKLING Yes, no, don't know. And that's it.
And then... We'll move on.
Right. We're going to move on to our first question.
First question is about the Moon and about Mars.
But whilst we're talking about the Moon -
the Moon, of course, has been in the news recently
because right now there is a big orange spaceship on the pad,
which unfortunately hasn't launched yet.
It had a hydrogen leak.
So the AA Roadside Assistance are currently,
certainly as we record this show, trying to fix it.
So hopefully it'll get up to the Moon soon.
There it is, Artemis 1, which is about to launch
with a dummy on board.
No people. Just a... Just... Just a mannequin.
But Andrew Thor...Thornet is in our audience.
Andrew Thornet. Hi, Andrew.
You've got the question about the Moon and one about Mars as well.
So, what's your question to the panel?
Well, the launch of Artemis is going to be the first part
of a programme that hopefully will end up with colonisation
of the Moon and Mars, so my question has got two parts.
The first one is, should we be spending so much money
on a project of this nature and on similar projects
when there are so many things back on Earth demanding our attention
and our funds?
And the second part of that question is, should we be considering
colonising anywhere when we don't even know whether there's alien life
on those other planets and there's a possibility we might wipe it out?
Wow. OK. It's... It's a really interesting question, Andrew.
Thank you very much. It's a sort of political question, as well.
Well, I'm going to throw it to Maggie first.
And, by the way, panellists, do jump in whenever, whenever you want.
But, Maggie, you start us off. Yes.
Well, I'm a lunatic. I love the Moon.
We know that. Yes. We...
I want to see a more diverse mix of people going to the Moon. Yep.
Yeah, but apart from all of that, it's quite interesting
because when you say sort of spending all this money on, sort of,
on these missions, as a space scientist, most of the programmes
I've ever worked on, on Earth Observation, trying to make planet
Earth a better place and space is really well positioned to do that.
So, secondly, I think it's quite interesting,
sort of, the way we go forward.
The planet Earth is getting very populated.
I would hate to go to Mars
and that's one of the reasons we keep on looking for life.
We don't want to go to Mars and sort of corrupt it,
but in the future, I think that's where our destiny lies.
At the same time, I do think we need to learn some lessons here.
I always say to kids, it's like we've had a wild party
here on Earth and - woohoo! And then we sort of look around,
we've made a bit of a mess.
So before we go anywhere else, let's sort out the problems here.
But space can really help us do that.
And also, I don't think it's an either or question, is it?
I mean, it's not like there is a pot of money that we're either
going to build hospitals with or go to the Moon. Right.
And it's actually much less money than people think.
It's important to realise, and I think this is missed,
that the money doesn't go to space.
Right? You don't make a big stack of banknotes and set them on fire
and end up on Mars.
Like, we spend the money on people
and technologies down here as well.
So it goes back into the economy.
The second bit of the question was about Mars and worrying
about life... Yes. ..on Mars as well, and that I'm much more worried
about because we try very hard, when we send Rovers to Mars,
for example, we make sure they're very clean
so that we're not taking Earth bugs to contaminate the ecosystem.
We don't send them to the places that we think are most promising
for life because we might contaminate them.
But all of that is going to be out the window when Elon Musk
and friends go on a holiday.
And so I would like to see us going near Mars,
put people on Phobos, the moon,
and you can look down and have your holiday view,
but until we've investigated and got our science
out of the Martian surface,
I'm not sure we should go wandering around on it.
Just very briefly, Suzie, we are extremely careful
when we send probes to probes, spacecraft to other planets.
Absolutely. And it works both ways as well.
So we're very careful about not contaminating
the Martian environment with bugs from the Earth,
but also we now have a plan in action to bring back samples
from Mars to the Earth.
And we're also very careful in the planning phase at the moment
of what we're going to do with those samples to make sure
we don't contaminate the samples, but also nothing in the samples
can then contaminate the Earth as well. Yes.
So it's definitely a process that goes both ways.
Andrew, thank you very, very much for your question.
We're going to have to move on.
We could talk about all these all night.
Unfortunately, we have to move on.
This is from... This is an email from Vince Brandon.
Erm, and again, it's a solar system question.
And I think I'm going to pass this on to Nial, I think.
Vince asked, "When the Sun first formed and the leftover gas
"and debris formed the planets, why didn't those leftovers
"just get drawn into the Sun under its tremendous gravity?"
OK, so we have to imagine how our solar system was formed.
And our modern idea is that,
and this idea actually goes back a couple of hundred years,
is that you have some big cloud, a nebula of gas, mainly,
and then some dust and in some concentration,
the gas starts to pull itself together under gravity
and forms the Sun.
And what naturally happens in those circumstances is a lot
of the rest of the gas actually ends up going in a circular orbit
around that nascent star,
because if there's any kind of angular momentum,
that's what it does.
The gravity is sort of exactly balanced by the centrifugal force,
if you like, and so that will happen.
You'll get a kind of disc of material, you see, like this one.
The planets then will form within that disc
and they will largely hoover up a lot of that gas.
Some of it will continue to go into the star.
Some of it may be thrown out,
but then, gradually, a new effect will take place.
And that is the radiation from your newly formed star
that has the effect of sort of pushing that gas out.
And so its force eventually
will disperse most of that gas that's left over,
that if it hasn't gone into something like a gas giant planet,
then largely it's going to be blown away by that solar wind
and radiation pressure.
And so that's why you don't really expect very much of
that gas to end up back in the star.
There's a bit of a misconception, isn't there, with a massive object
that it's there just pulling everything into itself.
It's not like a vacuum cleaner pulling stuff in, is it?
No, no. More, as I'm describing it, more like a hairdryer, in fact.
Yeah. Once the star turns on, you've got this wind and radiation
pushing material away instead. Got it.
So it's like a sort of... Is there a bit of a balance
between the gravity and the sort of the vacuum cleaner
and the hairdryer sort of both on at the same time?
Yeah, yeah. Sorry, it's a really terrible analogy. Yeah.
We've also got the fact the disc, as Nial said... The spin.
..the disc is spinning. Yeah.
And so because things are spinning,
you know, the Earth is falling towards the Sun all the time,
but we're actually in orbit around it. Right.
And so these things end up on stable orbits.
We know in other planets systems the planets careen about
and it's a bit more chaotic.
We seem to live in a nice, stable place,
and hopefully it'll stay that way.
OK, we've got a question that's been sent in by video
from Marcus Connolly. Marcus, what's your question?
Hi, guys!
So, my question is, is it possible that the rocky planets
around our Sun initially formed as gas giants,
then the solar wind blew the gas away,
leaving the rocky core in a thin atmosphere
while other gas giants - Jupiter and Saturn - were ejected
farther away or formed far enough away and resisted their gas
from being blown away?
Thank you.
CHUCKLING
Well, Suzie, I'm going to throw this one to you.
This is... What do you think of that hypothesis?
I like it, but I think it's probably not... Not true.
And there's a few reasons for this.
One is that the rocky planets and the gas giants
actually formed at different times.
The gas giants formed first, the rocky planets second.
So if the rocky planets used to be gas giants, then, you know,
somehow that doesn't quite work.
They would all have formed at the same time. Yeah.
Another thing is that actually the solar wind itself
isn't powerful enough to blast away the atmosphere around the planets.
So, on its own, that is unlikely to happen.
The solar wind simply isn't powerful enough.
So I think it's unlikely.
Having said that, we found some very unusual planets orbiting
other stars, elsewhere in our galaxy, elsewhere in the universe
that we can't really explain.
And we're beginning to understand things like planetary migration.
So, planets that move.
They're not or haven't always been where we see them today.
And that adds sort of some other excitement into their mix.
That means we have to re-evaluate our knowledge so far
based on just our own solar system.
Yeah, we've actually found a couple of systems where this theory
might be right. So it's not that the questioner was wrong... No.
..they're just in the wrong solar system. Yeah!
Am I not right in thinking that the solar wind
got rid of some of the Martian atmosphere or...
That's right. Obviously... Planets do lose atmosphere
and that that effect is stronger as you get closer to the star.
Yeah. So we know there are a couple of mysterious kinds of planets -
there are hot Jupiters around other stars, big gas giant planets
that are very close to their star, close enough that their atmospheres
are actually boiling away, and we can see that.
And then we also see these weird lava worlds which are rocky,
but they're so close to their stars that the surface would be
molten rock, would be lava.
And so one idea is that those lava worlds start off as hot Jupiters,
you boil the atmosphere for about a billion years or so
and you end up with just the tiny... CHUCKLING
That's quite quick for astronomy.
And you end up with this tiny core of a lava world at the end.
So it may be that for those extremes, this works.
But our solar system, we're a bit further away,
things are a bit calmer, and it's just the atmosphere that's affected.
Are we going to find more and more unusual,
strange planets with... Ooh, yes. I think so.
..processes that we just don't understand? Yes. Yeah. Yeah.
Because we do take our solar system as standard,
because it's our solar system. Yes. But when we look out there,
we're finding exotic stuff and sort of weird and wonderful stuff.
And I think now, as technology gets better
and we can see more out there, we will find more exotic stuff. Good.
I always... I always like finding exotic stuff.
Hey, right. We're going to move on.
Question number four. This is an email from Anthony.
Erm...
"Could an object enter our solar system and be big enough
"to be caught in the Sun's gravity,
"causing it to become the ninth slash tenth planet?"
Chris, I'm going to throw you that one.
People have looked at this because there are things
that you might want to explain about our solar system
by capturing planets and so on. Yeah.
It's pretty unlikely because anything that's passing
through the solar system would be moving reasonably fast
and it would have to be in exactly at the right angle
and at the right speed for the Sun to capture it.
So it's quite unlikely for a planet to be captured.
But we do think there are these wandering planets out there.
It may be that the most common type of planet is a rogue planet.
It's a planet that's been expelled from a solar system
and is out between the stars. But space is big.
The odds of encountering them and encountering them in such a way
that we could capture them is pretty low.
But presumably they're quite difficult to see,
actually, these rogue planets.
Yeah, we only catch them sometimes if they're lucky,
if they go in front of a distant star, then they can affect...
Their gravity affects the brightness of the star.
And that's how we know that they're there.
So these are planets that aren't orbiting stars. Yep.
One that wanders. No, they must have started...
Yeah, they must have started in orbit around a star
and been thrown out in the chaos of an early solar system. Yeah.
Can you sort of... Can we track them? Do we sort of know...
We just see them occasionally when they get in front of a star,
then we'll probably never see that planet ever again. Yes.
Cos they're not giving out any light themselves... No, of course.
..like the planets in our solar system. Yeah. Yeah. So there you go.
No, is the answer. Probably. Yes. Probably. Almost certainly not.
Probably, almost certainly not, Anthony. So there we go.
Right. We've got a question from Sheila O'Malley via video.
Sheila, what is your question?
Hello, pal.
My question is this.
If sufficient strides aren't made regarding the reduction
of greenhouse gases, could Earth become a runaway Venus
for future generations?
Wow. Thank you, Sheila. I'm going to throw this to Suzie.
She mentioned Venus, but let's talk about sort of planets,
generally. Sort of atmospheres.
Venus, Mars, could the Earth become something
like either of those planets?
Well, so, Venus, we often think of it as a bit like Earth's twin.
Yeah. About the same size, you know, a little bit closer in,
but that little bit closer in is really important.
And so there are reasons why Venus has had this greenhouse effect
where it lost all of its water
and it ends up in this really inhospitable environment.
If we burned every ounce of fossil fuel on the planet, which I hope
we don't do, then we wouldn't end up in in the situation of Venus.
That doesn't mean that we shouldn't be careful
about the fossil fuels that we burn,
but we're never going to reach that really extreme example.
And then Mars goes the other way.
You know, again, four billion years ago, Mars had an atmosphere,
had water, had a magnetic field, probably looked fairly hospitable
in some ways, and then magnetic field switched off
and it lost its atmosphere and now it looks the way it does today.
So, actually, one of the things that's really interesting
in planetary science is looking at examples that are a bit
like the Earth, but have little subtle differences,
to see where they went.
And then we can understand how the Earth fits
into this broader picture.
What... Sheila's question about Venus -
do we know what it was that sent Venus off
into its runaway greenhouse gas?
Being closer to the Sun as a good starting point,
being closer to the Sun, and so it lost its water.
It lost its water, and then the water
couldn't capture greenhouse gases.
And so it ended up in - we call it a runaway greenhouse effect. Yeah.
People use that language.
Talking about being close to the Sun,
I'm going to do a little handbrake turn and go into Mercury.
I want to very briefly talk about Mercury
because another Leicester project or part Leicester project,
BepiColombo, which is a spacecraft that's en route to Mercury
that you've been involved in.
What do we want to learn about Mercury?
What are the interesting things?
I think we've got some video of BepiColombo.
Is this a Mercury... Is this by Mercury?
Yes. So, BepiColombo launched in 2018.
It's on its way to Mercury.
It will go into orbit in 2025.
So we've only got three more years to wait.
We're a patient bunch in planetary science.
These are photos taken.
So as it approaches Mercury to get into its final orbit,
en route, it does laps and laps and laps of the solar system
in those seven years.
And as it does, it passes by planets and we use the planet's gravity
to change our trajectory and to slow us down.
And we have some cameras on board, engineering cameras,
that we often call selfie cameras
that take photos of the planets as we go by.
And so you can see some images up here.
We're looking at the planets as we go past them.
And these are the images that we have so far.
That's Venus, by the way, which doesn't look so exciting
in the selfie camera. It's pretty good!
So it does this lap - it's a braking system, isn't it?
To slow down. It does 19 laps of the solar system.
It goes round and round and round, gradually slowing down
and gradually getting closer to the planet Mercury
until it's captured by Mercury's weak gravitational field.
The exciting thing for me is there are two spacecraft.
They travel together and they split apart when they get there.
Having two measurements is a real game changer.
I look at space weather, the effect of the Sun on the planets,
and for the first time, fingers crossed, I'll be able to measure
what's coming from the Sun and the solar wind
and what the impact was on the planet.
Because I have two spacecraft, one upstream and one near the planet,
but it's also going to look at things like the geologic history
of Mercury, the thin exosphere, how that exosphere
and thin atmosphere is produced, what's happened over the surface,
how the planet's evolved over its lifetime.
So it's going to be a game changing mission for us, I think.
It's exciting. Right. We're going to pause on the solar system
and we're going to move into another big bit of space news
over the last few months.
And that is the launch and the photographs
that we've got from the James Webb Space Telescope.
They are absolutely extraordinary images
and we've got loads and loads of questions about JWST.
This is a question from someone in our audience.
Rika. Rika Smith. Where's Rika?
Hello, everyone. Good. What's your question?
Now that the JWST is up and running,
apart from the signs that we already know it is doing, what's next?
What else can it do?
What other surprises does it have and can we even talk about it?
Wow.
CHUCKLING
There are knowns and there are... And unknowns.
Things we know who we don't know. Yes. Maggie, what do you think?
As one of the scientists working on the telescope... Yes.
..we've already had these extraordinary images
that we can see. Yes. What do we think is going to happen next?
What do we... What's going to be revealed to us, do you think?
Well, the thing is, we don't...
I think it's a bit like Chris was saying,
we've got this brand-new toy,
and one of the things is it's very embarrassing
that James Webb ran very late and very over budget,
but it is chock-a-block with instrumentation and it's infrared.
So it's looking at sort of redshifts.
We're looking at some of the early parts of the universe.
And if you look at the, sort of, the science case
or sort of what we want to do with JWST,
it covers virtually everything.
We're looking sort of locally at sort of some of the planets
in the outer solar system.
We're looking at sort of, you know, galaxy formation.
We're looking at some of the first, sort of, the stars
and galaxies that ever formed.
It does a lot.
And I think one of the reasons it's been designed to do that is...
Oh, sorry, I didn't mention exoplanets.
One of my passions, exoplanets.
So it's designed to do a lot.
And so it's very hard to predict what it's going to discover.
But we know it's going to it's already started making discoveries.
Sort of, like, I think this is... Is this the Tarantula Nebula?
It is, yeah. It is.
And so the Tarantula Nebula, when you look at it
with a Hubble picture, because it's visible,
there are clouds of dust where visible light doesn't penetrate.
And now with the James Webb, with looking at MIRI
and also near spec, we can start doing an analysis
of some of the stars and we're discovering that they are
much younger than we anticipated.
So we're already sort of making discoveries,
sort of, for the first few steps that we're taking,
but because it's got so much instrumentation on board, I think,
well, one of the things I'd love it to discover is the potential,
the possibility of there being life on another planet.
It's looking at these exoplanets.
It's starting to analyse some of these atmospheres, you know.
So there's... I think it's lots of scope and lots of excitement
and lots of brilliant things to come in the future.
Just as Hubble did. Hubble transformed our understanding
of the universe with things like the Hubble Deep Field,
which gave us an understanding of how many galaxies
are in the universe.
And I think James Webb will definitely do the same.
You all... You all sort of have different areas of science,
of planetary science and engineering and other things.
Does the JWST sort of focus in all of your work?
Yeah, we've actually been competing against each other to some extent
because you put in bids and say, "I want to use it for this."
Yeah. And some of the ones I'm most excited about
are the people who are prepared for the unexpected.
So there are already bids in to do things like follow up
if an asteroid from another solar system passes through,
JWST will look at it.
If a bright supernova goes off nearby,
JWST will look at it.
If one of Nial's gamma-ray bursts go off, presumably, you'll...
Yep, I mean, another one.
I mean, a few years ago, you'll perhaps remember
there was a first detection of a gravitational wave... Yes.
..accompanying a binary neutron star merger,
which also gave rise to a sort of electromagnetic firework display.
That is something that if and when we get the next one and, you know,
they're pretty rare, these things, so we just have to wait and see.
It will be perfect for that.
Thank you. I've got a technical question, actually, for Pete,
and it comes from Peter Lockwood in the audience.
Peter, are you there? Thank you.
Yes. Why are there six rays of light emanating from all the stars
in those wonderful James Webb images?
Are they artifacts?
Are they... Oh, so you can see the picture behind?
That star doing a sort of star thing with its spikes.
Firstly, what do we mean by artifacts?
They're not artifacts, actually,
every star has them to protect itself and stop people
from wandering towards it.
CHUCKLING
No, they are artifacts. They are.
They are diffraction spikes.
They form when you have a straight edge at right angles
to the straight edge.
And the panels which make up
the JWST's main mirror array are hexagonal.
So you end up with six spikes.
But if you look very carefully, there's another two there.
And they come from the support for the secondary mirror,
which is, actually, it has a vertical and then it has
another strut which is 150 degrees round from that
and another one which is 60 degrees around from that.
And that's very clever because the diffraction spikes
that come from the two which have rotated round overlap
the ones which are produced by the hexagonal panels,
so you don't see them.
But the ones which are produced by the vertical strut, you can see.
So, they're little, tiny spikes.
So each star has actually got eight individual spikes.
Did the engineers know this in advance when they were doing this?
No, they just guessed it!
Yes.
LAUGHTER
I'm going to... Just similar... Well, not similar question.
But another JWST question comes from Glenn Saunders
and it's an email.
And Glenn says, "The plans for Hubble,
"for the Hubble successor began four years before the launch of Hubble.
"Are there plans under way already for a successor to JWST?"
Maggie. Yeah, and definitely.
And I think one of the things that defines an astronomer
is, "What's the next big telescope?"
It's only just been blooming launched!
I know, I know. But you've got to plan ahead.
What are you talking about, "What's next?"
It's called aperture fever. Yeah. LAUGHTER
And so it was the case because with the Hubble Space Telescope, I mean,
people were talking about the large space telescope 40 years
before it was launched, the JWST, sort of, a good 30 years. Yeah.
So, yes, the discussion is already under way
and some of it will be dictated by what JWST discovers.
But we do want to get, sort of, the next space telescope out there.
But one of the things we base it on is looking at
the electromagnetic spectrum.
Space telescopes are best and they give us the most information
when we are looking at wavelengths that we can't really detect
here on Earth because the Earth's atmosphere absorbs them.
So, like, things like, soft of, as part of the infrared,
part of the UV and sort of X-rays, gamma rays, things like that -
really good because they're nasty for us.
And so the Earth's atmosphere absorbs them.
So when we put space telescopes out there, we want to capture
these parts of the electromagnetic spectrum
because we can't detect them here on Earth.
And so we've got the JWST which was almost sort of
the predecessor of that was a telescope called Spitzer,
which was also an infrared telescope.
And now, but...
So the JWST isn't the, sort of, the next generation
of Hubble Space Telescope because Hubble was optical and UV.
So I think another optical UV telescope or maybe
a large survey telescope sort of looking out there.
But, yes, lots of Nasa, European Space Agency,
they're all looking at, you know, what comes next
and making plans for it now.
Given how long it took to launch JWST... Yes.
..and how unbelievably expensive it was and over budget
and everything else, do we...
I mean, when do you think
the next one will be? So... So the plans are reasonably...
We're beginning to get firm plans.
So the idea is for, say, a Hubble successor would be something
like a 6-10m telescope.
That's as big as the biggest telescopes on Earth today,
but in space. Yeah.
And an optimistic guess is that we'd look to launch that in 2039.
Erm, so a little less than 20 years' time.
That will probably overrun.
But we're talking about the next 20 years of development.
People are also talking about a big X-ray telescope. Yeah.
Sort of a new suite of great observatories
that will have to be international projects.
But there are people in the audience,
young people in the audience will be working on data, I'm sure,
from these telescopes that we're beginning to plan now.
And so it's really... I think it's really inspiring to be thinking
20 years ahead and we've got JWST for 20 years,
we're going to be busy.
We've got to think now about what we want to do next.
Do you... I mean, just very, very quickly, do we...
How long do you think JWST is going to run for?
Is it going to just keep going in the way that Hubble did?
It's about a 20-year lifetime? Yes. Although it's not like Hubble.
Because Hubble was in low Earth orbit, with the space shuttle,
we could go to Hubble... Yes.
..replace the mirrors, replace the solar panels.
JWST sits 1.5 million kilometres away from Earth. It's tricky...
It was a one-way trip when...
Yeah, yeah, you don't go that far. No-one's going out there to fix it.
So if things start failing, then unfortunately it's gone.
OK, listen. Brilliant. Thank you, panel.
We're going to give you guys a moment or two to pause
and reset your brains,
because it's Pete's turn to give us his wonderful star guide.
Take us through the astronomical wonders that we expect to see
in the night sky for the last quarter of this year.
That's right.
As we head into the last quarter of 2022,
there's a lot to see up there in the night sky
and in the daytime sky.
Mars will be a prominent object late evening.
And if you go out on the 17th of October,
if you look at Mars with binoculars,
there is a star just below it,
which is called Tianguan.
And that star
and the planet are a good markers to locate
an object which is roughly between them.
So if you look at the midpoint slightly over to the west,
which is to the right, you'll see there's a faint fuzzy patch,
and that's M1, the Crab Nebula.
That's the remnant of a supernova
which was witnessed to explode in 1054 AD.
Now, a few nights later, as we go into the 20th,
and you've got the peak
of the Orionid Meteor Shower.
And the Moon is largely out of the way this year,
so it should be a favourable appearance of this shower.
Orionid meteors appear to emanate from a point which is close
to the star Betelgeuse in Orion.
And when you see an Orionid streak across the night sky,
that's actually a tiny fragment of Halley's Comet
vaporising in Earth's atmosphere.
On the 25th of October,
we have a partial solar eclipse.
Now, this begins at 10:07 BST.
Maximum eclipse is at 10:58 BST.
And the eclipse ends at 11:50 BST.
The best eclipse will be seen from the north-eastern part of the UK.
They get about 35% of the Sun's diameter covered by the Moon.
Down in the southwest,
they get about 17% of the Sun's diameter covered.
Now, you should never look at the Sun directly, of course,
cos you'll damage your eyesight and you should never point
any equipment at the Sun unless you use appropriate
certified solar safety filters.
But there is another way to do it safely.
If you take a bit of card and you drill a hole 1-2mm
across and project the Sun's image through it
onto a white sheet of paper or card, that's a tiny image of the Sun.
Or you can get creative, as I did here with a tea strainer.
A tea strainer is a very important piece of kit
for any serious eclipse chaser. LAUGHTER
And each one of those dots you can see there
is a tiny image of the eclipsed Sun.
OK, so as we head into November,
then the planet Uranus will reach opposition.
And that means it'll be in the opposite part of the sky
to the Sun.
That means it's visible all night long and, theoretically,
it's at its best, its brightest and largest through the eyepiece
of a telescope.
As we head into December, then,
we have a very special event
because there will be a lunar
occultation of the planet Uranus.
We've had... This is the second one of these events this year.
There was one on the 14th of September as well.
This one isn't as well-timed
because it occurs in the afternoon
at about 4:50 BST in the afternoon.
And the twilight sky will make it
difficult to see Uranus
because Uranus is right on the threshold
of naked eye visibility.
The event lasts for about half an hour,
and as Uranus reappears
from behind the Moon,
the sky will be a bit darker.
So that's probably your best chance to actually be able to see it.
So if you get clear skies, go out and enjoy this beautiful world.
Great. Thank you very much, Pete.
Erm, talking of supernova, which you mentioned,
we've had a question about that from Lawrence Hazel.
What's your question about Supernova?
Hi, panel. Hi.
I've got a question to ask.
Have we ever observed supernovae in real time
and within a moderately close distance to Earth?
Also, how long does it take the average supernova to play out?
Is it something relatively short,
or is it over decades or hundreds of years?
Pete, that's a really interesting question.
I've never thought of that.
You must have seen millions of supernovae, all the time.
I've seen... I have seen supernovae in distant galaxies. Yep.
But to get one which is really close to us is exceedingly rare.
The only one which has been close to us since the invention
of the telescope occurred in the Large Magellanic Cloud,
the LMC, and that was about 168,000 light years away.
So quite distant, still.
We should just actually just pause and explain what a supernova is.
The main one that people think about is when you have
a massive star which runs out of fuel, basically,
and everything can't be supported in the star.
So the star collapses into its core and just explodes.
Super... Nova just means new star.
Supernova means super new star.
Bright new, star - right?
These things can outshine a whole galaxy.
We're kind of excited to see one in the Milky Way
and also a bit terrified if they're too close... Yes. Mmm.
..as we heard in one of the archive clips.
But what you're seeing isn't the light
from the initial explosion.
In almost all cases, what you're seeing
is light from the decay of radioactive elements
that are created.
There's such an amount of energy and such a density,
material rushing out from this exploding star
that you get a runaway set of nuclear reactions.
And then over the course of weeks and months, this dies down.
So what you see is a rapid rise in brightness
and then a slow fade over the course of months.
But, Nial, you work on cosmic explosions.
This is... Yeah. Yes, I do - of a particular kind.
So the kind I work on are called gamma-ray bursts,
which are also a kind of explosion of massive stars.
And in that case, the initial flash we very much do see in real time,
it's a flash of high-energy, gamma ray radiation.
And there, we're talking about things which are like
a billion times brighter than the galaxy they're sitting in.
So they're really the most extraordinary kind of explosions.
But the ones we see are all very, very far away
and over and done with - at least that flash of gamma rays -
in a matter of seconds.
We're going to move on from exploding stars to black holes.
Everyone likes talking about black holes.
We've got a question from Sebastian. Where's Sebastian?
Sebastian Thornton is in our audience.
He's got a really good question about black holes.
Hi, Sebastian.
Accretion discs around black holes are extremely hot.
So is there any chance of them generating nuclear fusion?
Wow.
"Accretion discs around black holes are extremely hot.
"Is there any chance of them generating nuclear fusion?"
So we should first off thank you very much, Sebastian, for that.
Let's establish what we mean by accretion disc first, I think.
Nial. Right. OK.
So you've got something like a black hole.
It's got the very intense gravitational field.
That, of course, will - although we said before
that material tends to go in circles
around gravitating objects - to an extent,
you can also get, if you've got a kind of gas cloud coming in,
let's say, from another star,
material that's come off another star,
there's a certain amount of friction goes on and that will tend to pull
material in and it creates this kind of a disc kind of effect.
And it gets extremely hot, as you say,
and it gets to the sort of temperatures - actually,
well in excess of the temperatures that you get inside stars.
And so we know that nuclear reactions are happening
inside stars, you quite rightly then say,
"Surely they should also happen in accretion discs."
And, you're right, it turns out that you can get a certain...
You do expect to get a certain amount of nuclear processing
going on in those accretion discs.
But it also turns out that it's relatively small peanuts
in terms of the amount of energy that creates compared to that
super amount of energy that you get just from the gravitational pull
of the material into the accretion disc -
that creates, releases an enormous amount of energy.
It makes everything very hot.
That's how you get those high temperatures, very bright...
And so these things shine with very intense radiation as well.
And it's principally that gravity power, really,
rather than the nuclear.
We should say as well, that nuclear fusion, of course,
that's the process that powers the stars. Right.
Which is, erm...
But, actually, what Nial points out is it's pretty...
It's a pretty terrible way to generate energy.
If you've got a large lump of matter and godlike powers
and you want to generate as much light as possible,
you're much better off throwing it into an accretion disc around
the black hole when you get... CHUCKLING
..about 10% of the energy gets turned into light,
whereas over the course of its lifetime,
the Sun only converts 1%... It's rubbish.
It's rubbish, basically. We should be orbiting a black hole.
This, of course, is the famous photo from a couple of years ago
of a black hole, which I think looks rather like a plain Hula Hoop.
Continuing our...
LAUGHTER
Which is my favourite space crisp.
Anyway, we're going to move on from black holes to dark matter.
We've got Adrian Smith in the audience.
Adrian, where's Adrian? Hi, Adrian.
Numerous experiments have failed to detect dark matter.
Is it time that we contemplate the dark matter does not exist
and start to pay proper attention to alternative ideas,
especially those that do not require any modification of gravity
or any new physics?
CHUCKLING
Adam, do you know, the word I likes that you used was proper attention.
Proper.
LAUGHTER
Chris, have you not been paying proper attention?
Well, you know, I'm kind of busy. LAUGHTER
No, but it's an interesting conundrum.
So we should say...
So this dark matter is an explanation for a set
of observations that we see in the universe,
which is that on all sorts of scales, from the universe
as a whole, as we see in these big computer simulations on the screen,
to sort of the behaviour of stars in galaxies,
and indeed galaxies in galaxy clusters,
it looks like there's more stuff there than we know to account for.
And so one way of explaining that is -
and astronomer's like simple explanations -
there must be more stuff in the universe
than we thought there was.
And we've done some tests, and we don't think that stuff
could be normal matter. It can't be made.
You can't just say there's more electrons, protons, neutrons,
planets, stars, black holes.
There aren't enough of those things.
And so one option is to invent a new kind of matter.
We call it dark matter.
And, as you say, there have been all sorts of experiments trying
to detect it and to think about it.
And we haven't got a direct detection.
We've never caught a dark matter particle in a box or seen its effect
on anything here on Earth.
The other option is to play with physics,
to say there must be some new force
or some new idea that we're missing.
This is the really exciting solution.
Dark matter is actually the boring solution, because all it says
is there's some extra particles in the universe
and new force would be fun or what... Actually, people, including
myself, have spent time doing is trying to fiddle with gravity
so that you can...
Maybe gravity works differently on large scales or something like that.
The trouble is that you really shouldn't fiddle with gravity
unless you know what you're doing.
It turns out... It's what my grandmother always says!
Exactly. If only I'd been warned!
Because it's really easy to break the universe!
It's quite hard... You can fiddle with gravity in such a way
that you don't need dark matter in galaxies, but then you find
that solar systems don't work any more.
And I'm rather attached to our solar system. Yeah.
Or you could fix it on large scales and solve the cosmological problems.
But then you discover that you've got the wrong number of galaxies. So, we haven't yet come up with
an idea. New ideas would be good... There's something, though. The point is there's something, we just don't
know what it is. We've got these observations that we need to explain. And either you need
dark matter or you need a new idea or gravity is wrong. I'll put that down in the "It's complicated" pile.
Yeah, yeah, put it in "We're working on it"!
I think people are coming up with these different ideas and playing with them and trying to find
solutions, but we haven't found one yet. No. Exactly. Talking of "we're working on it", as you know,
this is... This is a "It's complicated" pile.
It's a Nial question, I think.
And it's an email from David Storrs.
Thank you, David.
Time is of the essence,
just before I give you this question, Nial,
and I'm not going to let you... See if you can answer this
to our satisfaction in under a minute.
What is the universe expanding into?
OK, a very good question, a question I'm sure many of you asked.
If you haven't asked, you should ask yourself -
why haven't you asked this question?
What is the universe expanding into?
We have this picture in our heads of the Big Bang, giant explosion,
flying stuff all off into space.
Wrong picture.
Instead, I would ask you to picture an infinite rubber sheet.
If anyone at home has an infinite rubber sheet, you can get out,
play along. On this infinite rubber sheet,
we're going to sprinkle an infinite amount of loose change.
So, coins everywhere distributed.
Those coins are our galaxies.
Now we stretch the rubber sheet.
It's an infinite rubber sheet.
There is no edge, there is no boundary to our distribution
of coins. But they started off with one density
and, after some period of expansion, as we know the universe
is undergoing, they're further apart from each other.
So, that's the kind of universe we think we live in.
Why do astronomers cook up such crazy ideas?
Was it something that we felt was just so wonderful that, you know,
that must be it? It's sufficiently weird that it'll spook everybody
out. The answer is really no.
I mean, fundamentally, it comes down to observations.
As far as we can tell, in every direction,
the galaxies are distributed much the same.
We have to move on.
One of the other great questions, we've had so many
questions about this. Aliens.
We love questions about aliens.
Before we move on to the question about aliens, I just want to pay
a little tribute to the great astronomer, Frank Drake.
Dr Frank Drake, the American astronomer,
who was so central in setting up SETI and the search
for extraterrestrial intelligence with Carl Sagan and others.
And, of course, when we think of Frank Drake, we think
of the Drake Equation, which was a framework for asking the question
is there life beyond Earth?
And, of course, Frank had all these different parameters
that you could multiply together, which would give you an answer.
And, of course, it wasn't an equation as such.
It didn't actually give you an answer, but it was a way
of approximating, a way of exploring,
getting our imagination thinking about how do we ask this question
sensibly. Anyway, Frank Drake, lovely guy.
We're going to take a little audience poll
while we're on the subject of SETI.
Hands up if you think there is life out there in the universe
beyond Earth.
Crikey.
That's everyone.
Hands down. Hands up if you don't.
Hands up if you think it's just us.
No-one... Oh, no, no. There's one. Where?!
Yes. In the blue. Just one there.
Where? Do we have a microphone? Where's the microphone?
Oh. Come, bring me the microphone! Thank you.
Right. Guy in blue shirt. I'm going to pass you the microphone.
Why do you think we're alone in the universe?
Well, the conditions for life are just so highly improbable
that it's very unlikely to happen anywhere else.
And the number of coincidences which have made life on Earth
possible. But even sort of very simple life, even kind of, you know,
single-cell life, perhaps.
Well, even that's unlikely, I think.
Interesting. So, you think it's just completely... Hmm, yes, I mean, even if the conditions for life
are perfect, the probability of it actually forming is very small. Yeah.
Interesting. Thank you very much indeed.
What I find interesting about that is that it's...
Hardly anyone thinks we're alone.
The general consensus is that there is life, be it simple,
or otherwise, out there simply because of the numbers,
the sheer numbers of planets.
Right, continuing our alien signatures theme,
this is from Chris Pitt via video. Chris.
Hi, panel.
I've been thinking about the accumulating space junk
orbiting the Earth and wondered if it would give our planet
a unique signature, given that we have or could develop a probe
to detect that.
So, my question is, with our planet serving as a positive control,
could such signatures be used to detect intelligent life
that exists or has existed on exoplanets?
I think that's a very sensible question.
So, back in Frank's Drake... In Frank Drake's time,
they were looking at radio signals, "Can we find radio
"signals on exoplanets?"
But now there's all kinds of other ways we can look at things
like the spectra from atmospheres of other planets.
Could we look at space junk around exoplanets, for example,
and go, "Oh, look, we've found aliens".
I want to ask Suzie about this picture, actually, because I know you look at...
You've seen this image a lot. There's something a bit misleading about this image, isn't there?
Yeah, it's meant to give you an idea of the number of objects in orbit
around the Earth, but the misleading part...
That makes it sound intentional!
The thing that I think can be a bit confusing about it is that
some of these objects are the size of a fleck of paint,
and they appear, in this, to be the size of a city.
And so, from this image, it looks like near-Earth space
is incredibly congested.
And I'm not underplaying space debris as something
that we should be concerned about and be discussing
over the next few decades.
But this picture does make it look like near-Earth space
is much more clustered than it really is.
But you could look for not junk, but this is space junk or satellites
around a planet. People have talked about advanced civilisation
building vast space stations
or orbiting solar panels around their star,
things called Dyson spheres or Dyson swarms.
And we found, a project I helped run called Planet Hunters,
found a star that was blinking strangely,
and this bunch of people we'd never met published a paper that said,
"Ah, this is clearly signatures of alien megastructures"!
It's quite a day when you get... Your phone rings in the office
and they say... And somebody says, "I hear you've discovered aliens".
And you're not sure what they're talking about. We have heard a lot
about alien meg... The Avi Loeb... What was the...?
Oh, well, this is... Yeah, people have talked about Oumuamua,
which is the interstellar asteroid that came through the solar system,
which a certain Harvard astronomer thinks is an alien spaceship.
But it's not.
But it's the kind of... But it is a sense that you can look
for weird things, and as I said, people have looked for dust
from mining in... Around stars.
People have looked at distant galaxies to see if they can see
bright infrared sources that might be alien power stations.
People have looked for flashes of laser light
that might be communications.
We're generally up for looking for weird things in the universe
anyway... Yes. ..because either you find aliens or you find
some exciting new astrophysics. Yes!
Oh, it's never aliens! Either way. It's never aliens!
It's never aliens. Suzie, just a final word.
No aliens on Mercury?
No aliens on Mercury, sorry. Really? I know. Not even... A burst bubble,
there. ..in your wildest dreams? No. No? Damn.
Right, we're going to move on.
Angus O'Gallagher, I hope I'm pronouncing your name right.
This is an interesting question about habitable planets. Angus.
Hi, panel.
My question is, can habitable planets exist
around red dwarf stars?
We have already discovered lots of habitable worlds
with different space telescopes - Kepler, Hubble, James Webb -
all of these candidate worlds around stars like our sun.
But if they exist around red dwarf stars, then that makes our odds
much, much better.
I think Angus has been watching The Sky at Night too much,
if that's possible.
Who wants to have a go at this. Chris?
We should explain what a red dwarf is. Let's start with that, yes.
Because to those of us of a certain vintage, it's a comedy show,
but it's also a small star.
So this is an illustration that shows a red dwarf to scale.
So the yellow thing here is the sun.
There are stars bigger than the sun that we're used to talking
about because they go supernova and so on.
But most of the stars in the galaxy are smaller than the sun.
They can be, sort of, almost planet size.
And we have, in fact, found lots of planets around red dwarf
stars, and some of them are close to their stars, but in what people
sometimes call the Goldilocks zone.
So the region where, if you took an Earth-like planet and put
it there, conditions would be reasonably temperate.
You'd have liquid water, and so on.
The trouble is, red dwarf stars maybe have much more active
space weather, so they have flares.
This is your territory.
Suzanne, yeah, can you tell us a little bit about
exoplanet space weather?
I don't think we entirely know, actually, about, about the activity
of red dwarfs, but there have been some studies suggesting
that they are quite active and habitability of planets does
depend on the star and the stability of the star.
So we're pretty lucky.
We have big space weather events that happen very rarely,
and we are on a planet with a magnetic field far enough
from the star that it doesn't decimate us.
But you can imagine that the habitable zone around a red
dwarf - again, this is your area - is very close to the star. It is.
And so if there was a big event on the star itself, it would probably
have quite a big impact on the planet.
So habitable, perhaps in terms of having liquid water
and the temperatures and that kind of thing, but maybe not habitable
when it comes to the sort of environment of the star.
Yeah, read the small print before buying an inhabitable planet
That's the key. Good advice.
Right, we're going to move on. I absolutely love this question.
This was a question that made loads and loads of headlines a couple
of years ago, and it's about phosphine in Venus.
Alex, your question.
Hi, panel.
One of the most exciting episodes in recent times was the discovery
of phosphine on Venus, suggesting signs of Venusian life forms.
Is this hypothesis now shrouded in doubt?
That is a really good question.
It was a terrifically exciting headline talking about signatures.
Phosphine in the Venetian atmosphere.
Suzie and Chris, there's been a little bit of...
We should probably just, the story first, what was seen
and then how it's evolved over the couple of years.
Well, we had this as a Sky at Night exclusive because the person who led
the team, Jane Greaves, is an old friend of the programme,
and she was very excited because she's found phosphine
in the atmosphere of Venus
by using telescopes here on Earth.
And phosphine on Earth is made by things like penguins,
it's made by life, and occasionally by factories.
It's not a chemical that forms naturally.
And so if you find phosphine and it's not formed naturally,
then you've found life on Venus, which is this hellhole of a planet.
So it's a very strange thing to have found.
The discovery came out.
It was immensely controversial.
There were papers published that said it's rubbish,
it's definitely not phosphine, you don't know how to use
the telescopes properly, you haven't got rid of the background,
it's a difficult measurement. Jane and her team are standing by it.
They've actually got new results from different data with a different
instrument that seem to confirm that the phosphine is there,
though at a different and not quite as strong a signal
as they thought they'd found. That's now being attacked.
It's just controversy all round, but it's a fascinating thing.
And new measurements are being planned.
So the main telescope you want to use for this is Alma in Chile.
They've got more Alma time and that will be the definitive measurement.
I think the question of how they observe phosphine is one
question that we've been discussing.
The other question is, is it life if they have observed phosphine?
There are other ways that you can produce phosphine so it doesn't mean
that there's definitely life.
I think one of the things that captured people's imagination
was that they'd observed this phosphine up in the atmosphere
at a place where the temperature is not dissimilar to the temperature
on Earth and the pressure is about the same as on Earth.
OK, the atmosphere is highly toxic.
So there had been, sort of, conversations rumbling
around this area of Venus before.
I think what I'd really like to highlight about
this announcement and the subsequent discussion, is that I think
this is a good example of how science should be.
So somebody gets excited and publishes something
and then everybody else goes to try and verify that.
And there's a good, enthusiastic scientific debate
about whether the observations prove one thing or prove another.
And this debate's been rumbling on for a while now, hasn't it,
since it was first announced?
And I think that's great. This is how things should be.
And now what we've concluded is we need more measurements.
Good. Good point.
It brings us to our final question. We've run out of time.
We could talk about all these questions forever.
But sadly, our final question is upon us.
Happily, it's a very good question.
And it comes to us from Bernie Major,
which is a very good name for a Sky at Night viewer
who's in our audience. Bernie, where are you?
Hi, Bernie. Next to Tim.
Good evening.
With Shaun the Sheep gaining a place on the Artemis I mission
around the Moon,
which cartoon character do the panel think deserve a trip into space?
Wow, what a question.
Shaun the Sheep is about to go around the Moon on Artemis I
at some point.
This is a training image.
LAUGHTER
I must admit, I'm really jealous. I want to go on Artemis I.
I know, they could have... Exactly. If they'd asked me,
I would have done it. I don't mind whether it's a test mission.
Let's start with Pete at this end. OK. A cartoon character.
Who do you think should merit that trip?
Well, I've been greedy and I've picked two, actually.
I think Garfield would be hilarious because you could
stick it to the window.
But also it would be quite funny to take SpongeBob up there,
because if the craft were ever kidnapped by aliens,
they would be looking at SpongeBob, wondering what the hell this life
form was from our planet.
SpongeB-... Nial?
Well, I'm going to go for Scooby-Doo because, you know, you never
can tell when you might meet some spooky space ghost
that turns out to be...ooh,
Elon Musk.
With Scooby-Doo, it's never supernatural as well.
It's always, like, the fairground owner.
It's always that rich businessman kind of character.
We'll get the answer to dark matter. It's not a mystery anymore!
Yeah. Scooby-Doo, that works.
Maggie? We know what Maggie's going to choose. With me, it's simple.
For me, it is always The Clangers. Always.
And this is an opportunity that I got because they made
an episode of The Clangers recently and they featured
a little Maggie doll.
So my childhood dream was to meet The Clangers, and I got my
dream come true.
So I'd like to return the favour and invite The Clangers to come
and see our moon, because I think it has to be done, really. I think so.
I'm become amazed they haven't put a clanger in the action.
This summer I had the wonderful experience of seeing Maggie
deejaying with The Clangers,
which was something you should all experience.
It was a clanger rave. And I'll tell you, it was it was amazing.
Nice, nice.
Suzie, who's your moon-based cartoon?
My moon-based cartoon character is Zebedee from The Magic Roundabout
because I think Zebedee in space would be quite something to watch.
I think that would be pretty trippy.
I mean, Zebedee at the best of times is pretty trippy.
But in microgravity - bing-bing-bing!
Exactly!
Have we done...? Oh, Chris.
Yeah, well, the Moon's old hat.
So I'm starting a campaign to get Marvin the Martian from Bugs Bunny
back to Mars. I think it's the least we can do.
Yeah. Am I allowed to have one? Yes.
Can I do Homer?
I want to do Homer Simpson in that brilliant episode where Homer
went to the Moon and he was eating crisps, and they had that
2001: Crisp Odyssey.
Which brings us back to the end of the show.
I just want to say a huge thank you to everyone who sent in questions.
Thank you very much to our studio audience.
That is the 825th episode of The Sky at Night.
From me, goodnight.