Episode: 3504
Title: HPR3504: James Webb Space Telescope
Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr3504/hpr3504.mp3
Transcribed: 2025-10-25 00:39:46

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This is Haka Public Radio Episode 354 for first day the 6th of January 2022.
Today's show is entitled, James Webb's Space Telescope.
It is hosted by Dave Morris and is about 45 minutes long and carries an explicit flag.
The summer is, Andrew and Dave watch the launch of the J.D.L.U.S.D.
Hello everybody. Welcome to Haka Public Radio. This is Dave Morris.
I'm talking today about the James Webb Space Telescope.
Probably get that wrong a few times more.
So here's the overview. On Christmas Day, that's 2021, at 1220 UTC the James Webb Space Telescope was launched.
This is the largest telescope ever sent into space and the project has been delayed for many many years.
The entire astronomical community, those into a podcast and stuff anyway, was very nervous about the launch after the time that it had taken.
And the amount of money that had been spent. And they're also nervous about the phase that will follow is the telescope is set up.
So there's a lot of work required to get it all configured and ready to go.
So I mentioned this launch to my friend and co-host Andrew Conway.
And he being a professional astronomer back in the day.
And myself being quite interested in the subject of astronomy in general.
Just as an amateur, we got together on mumble to witness the launch and chat about it.
I asked Andrew if he was happy with me recording it as we were starting.
And so he was quite happy with that. And that's what we've got here.
Basically this show is a little bit of preamble just to bring up to speed with the James Webb Space Telescope which is normally called JWST.
I'll be mentioning that most of the time. I wanted to just give you a summary of what it's doing.
What I've done in my notes is to simply extract the first few paragraphs from Wikipedia page which is linked in the notes.
And I'll just briefly read through them. There's quite a lot of condensed information in here.
And I don't want to bore you to death telling you too much which you could read for yourself.
Partly what I'm doing here is covering stuff that's covered better in other places.
So I think mostly it's best if you go and look if you find it interesting enough from what we talk about.
So the JWST is a joint development between NASA in the States and ESA European Space Agency and the Canadian Space Agency called the CSA.
And it's named after James E. Webb who's the administrative NASA from 1961 to 1968 and played an integral role in the Apollo program.
It's intended to succeed the Hubble Space Telescope as NASA's flagship mission in astrophysics.
So as I said before the JWST launched ended up being 25th December 2021 and it used an Ariane rocket provided by ESA.
It's going to be an infrared telescope, that's what it's built to be, which is a different range of light sensitivity than Hubble.
And so it's going to be able to spot things that Hubble couldn't.
It's going to be doing a lot of investigations across the fields of astronomy and cosmology, particularly some of the most distant events and objects in the universe.
Such as formation of the first galaxies and that type of thing, detailed atmospheric characterization of potentially habitable exoplanets, it says.
So in other words they're going to be hunting for exoplanets around very far away stars and they also will have the ability to detect information about the atmospheres of these planets.
So that's a good opportunity to say that one might be inhabited because it's oxygen in the atmosphere which is not a common thing to find as far as I understand it.
The JWST has a mirror made of 18 hexagons and they made of gold-plated brillium and it makes a 65 meter diameter mirror which is much larger than Hubble's which is 2.4 meters.
So the infrared capability will allow it to observe high-red shift objects that are too old and too distant for Hubble to see.
So the red shift, I'm a little bit hazy about exactly how that is, is to do the fact that the origin of the universe was a time and a distance away and during since creation and the present day the universe has been expanding.
So light that was sent out by the original Big Bang, it tends to be called, will have changed frequency, weight length, sorry, because it's been stretched, it's a thing that light will do.
Anyway, the telescope has to be kept very cold to see the infrared without any interference from itself. So it's going to be out in space in a point called the Sun Earth Lagrange point number two, L2, which is about 1.5 million kilometers from, that's nearly a million miles.
And it's going to have a big sun shield, it has a big sun shield facing the sun which will protect it from the sun's heat and itself is quite an amazing achievement I think.
So the development began in 1996 with a plan for launch in 2007, so you can see how much time has been added to that with a $500 million budget, but there was lots of issues and I won't read the whole list here.
But lots and lots of delays and problems and things that needs to be resolved, I think the Covid pandemic hasn't helped.
So it's way way over time and it's massively over budget to, I think 10 billion is the figure at the moment.
So it was launched from French Guiana, which is close to the equator because launching things from near the equator gets a boost from the rotation of the earth.
And we watched it and chatted about it as this happened.
So I'm going to patch in, splice in the audio from that particular event of watching it in real time and talking about it.
So there was a slight oddity with the audio, there's a background hum from my end, but I've been fiddling with Audacity's notch filter thing to try and remove it because I think it's, I remember what frequency I took out, but it's a little bit less.
I think it's because I've got a fan heater in this room and I forgot to switch it off.
The point about the altitude of the rocket as it was heading up into space.
The final stage was left, everything else had been shed back to earth.
That final stage, it actually reduced in altitude and, and we pointed this out, puzzled us to why it was happening.
But I've since found a YouTube episode from a guy I follow Anton Petrov, who talks a lot about these sorts of subjects explaining that this is one of the necessities for getting a sort of free boost of speed from the orbit around the earth, the gravitational push, I think.
I think not 100% certain I understand it, but maybe you will understand better when you come to look if you're interested.
We were chatting about another orbital mechanics related mission, which is ongoing at the moment, which is heading to Mercury, but I couldn't remember its name.
It's also passing by in the planets to get its speed, I think it needs to speed up on its way to Mercury, and then it needs to slow down.
So it's using other inner planets of the solar system to do this.
I couldn't remember its name, but later on I remembered it's called Beppy Colombo, taking seven years from launch to get to Mercury.
I think it's due in 2025, so I'm going to just read the last section of the notes and then splice in the audio.
So just to say that after launch, we saw it up until the point that the telescope had detached from the final stage, and we saw the sun, not the sun shield, the solar panels coming out,
with a live camera from the final stage.
So since that point, up until now and today is the 2nd of January 2022, it's on its way to that L2 Lagrange point.
And we talked a little bit about Lagrange points in the talk, but it's a really hard concept to pass on, I think.
I don't fully understand how it works if I quite accept that it does, but you might want to have a look further by following up the Wikipedia article, for example, about how Lagrange points work.
So while JWST is on its way to L2, it's getting yourself ready, so it's unfolding things which will fold it up inside the rocket.
And there's a really interesting site, which I think is called a deployment explorer, so you can actually scroll through steps of where it's actually going to be at different times.
See where it is now, and what's happening with lots of explanation about what's unfolding and how it's working and all that stuff.
So the sun shield's getting opened, the mirror itself, which is folded, will be unfolded, and so on.
Once it gets there, it's going to take another, I don't know, quite a number of months, I think, before everything is set up properly, because they need to calibrate everything and get the mirror set up properly.
So there's tons and tons and tons of information about this, and you follow some of the links I've put in the notes, which should hopefully get you further into the subject.
Just the final thing to say is that the launch that Andrew and I watched is visible on YouTube. Hopefully you find it interesting enough to go and dig deeper.
Okay, that's all for my preamble, and now we go over to the live recording.
Oh, you're recording this? Shall we not? No, it's fight. Yeah, go ahead.
Should warn you that I've got a multitasking in the kitchen.
I've got a schedule for Turkey, but luckily, very kindly, the James Webb telescope has been launched in a window.
Because my T-minus zero when Turkey comes on the oven is not until the past two. I've got nothing to do but remove the foil.
Yeah, yeah, yeah. Just brown it nicely and all that sort of good stuff.
Good, good. Why are they all walking up there?
I think that they can actually go on. I think these are the guys actually in French Guiana, are they?
I think this is the actual control center at French Guiana. I think they're all journalists and stuff and they're going to go and see the actual lift off in, I would guess, I don't know.
Oh, isn't that another tutorial? That is, in fact, the control room.
That's the control room. Yeah, there's director of operation. It's just now on the screen.
So yeah, I think that's, is it Kuru in French Guiana? Because they were saying...
I thought you had an iron in front of them in their back, but they're models of rockets.
Yeah, yeah, that's an Ariane 5. I think the one, and there's the real Ariane 5 over there.
Yeah. So that's the ESA contribution. It's the Ariane 5.
So yeah, we're all going. It's...
It's a volcanic engine, a volcanic engine, then 38 seconds.
Yep. They fire up one engine, then seven seconds away, they fire up the booster, apparently. They were telling us in the preamble.
Yeah, I'm looking at the cylinder, because I feel like it's longer than a rocket engine.
Hopefully that isn't the cylinder. It should be catching fire, Ian.
I've actually set the kitchen slightly on fire this morning.
The baking paper poked into one of the gas hob windows.
Oh, no.
And I went, it looks like we're off.
Yep, yep, yep. We've got a rocket starting up.
That's the main engine, I think, and that's the booster. Wow, and there it goes.
Yeah.
My goodness, me.
It looks slow when it takes off.
I know, I know.
It's just sort of crawling in the end, and then it's going on hell of a speed.
Well, it's accelerating, isn't it?
Because, yeah, this capability is what it needs to achieve, as we know very well.
Do you hear that?
What was that?
Well, I got, I don't know.
I've got a strange message.
My phone's saying, no, no.
Hearing notifications.
I don't know where it came from.
I've got a problem with it.
Anyway.
And now we're into animation of what's going on up in space or wherever.
It's probably not reach space yet, I don't know.
Yeah, I don't think they've got another rocket flying alongside filming it.
No, I don't have a graph.
So I don't know.
Yeah, they've got a fair way to go to get at the atmosphere I imagine.
Do you remember back in the days of the BBC Micro and 8-bit computers,
there was a space shuttle simulator game?
Oh, no, I don't remember that.
And there was a graph that looked very much like the one that we see in the screen.
It looks like it's a parabola on its side.
And showing that was an altitude of time.
And then the game you had to put an input to keep the space shuttle blasting off on that curve.
I was impossible.
I could never do it.
No, I never played those such things.
I was more into space invaders and Galaxians and Chucky egg, I think was worth.
It seemed to get on quite well with Chucky egg.
I think it was a game.
I think there was some...
There was the pistachios coming off.
There was fifth full to the physics.
But that didn't make for an entertaining gameplay.
Yes, yes.
There was a version of Asteroids, wasn't there on the beam?
So it seemed to record?
Yes, several.
I remember playing that and that's one where you got...
It's not proper.
So it's still mechanic stuff.
But it is, you know, a bit more similar to reality.
You can't whiz off in one direction and stop.
You've been around and fire rockets in the opposite direction, all that stuff.
Oh, yes.
Thanks for it.
You had to...
No, no.
Respect Newton's laws, yes.
I think my approach was not to move in that game because I couldn't stop again.
Yeah, true, true.
Yeah.
It was all too easy to find yourself unable to go anywhere that was sensible.
Oh, they've separated.
What they've done, they've opened the stage
which contains the telescope itself.
Just explaining.
It's been just, I guess, I guess...
I guess now I have to clear that up.
Let's hear it see if we can do that now.
Yep, yep, yep.
So because the rest of the journey is 30 days I was hearing
to get to the L2 Lagrange point.
And over the 30 days they're doing all the deployment of everything.
So the whole thing is folded up.
So it's got a sun screen which is this sort of tinfoily stuff
which is all folded inside.
They have to bring it out, open it out,
underneath the telescope such that the telescope can be positioned to point out of the sun
and then look wherever the obvious is pointing at.
And so that is going to be everything.
The actual mirror also folds out.
You can see in the graphic there are three hexagons on the side.
Those are part of the mirror which fold out to be called Plano with the rest of it
which is on the side you can't see.
So yeah, it's going to be, this is the really,
this is the bit that everybody's scared of.
You know, the next 30 days it's something going to stop these things from unfolding.
It's all this sort of stuff that's that people are talking about.
Yes, I'm just reminding myself that the L2 Lagrange point is about one and a half million kilometres
on the other side of the earth from the sun.
So if you draw a line from the sun through the earth and go keep going from that 1.5 million kilometres
which is about a hundred of the sun distance then you come to the L2 Lagrange point.
And you can work it because the forces balance out there in this inner which sends the forces balance out.
It's quite interesting.
I did that to all the physics behind that at university.
I think that's interesting.
I was chatting to Ken about this on Matrix this morning and I think he's watching as well actually.
But he was saying, oh, I could do with somebody to come and explain how L2 Lagrange points work.
It's a good HPR show there.
So yeah, it's been a few years.
I mean, I used to devote almost to either 20 lecture course.
I used to do an astronomy at Glasgow University.
You know, it was kind of like a non-mathmatical but quite rigorous introduction to astronomy.
And it took me most of an hour, maybe almost a whole lecture really to get through Alotides worked which is the same idea.
So you're moving into a rotating, just an accelerating reference frame and it's not easy to intuitively.
It's intuition-busting, that's the problem.
The only real way to do it as Lagrange did it back in the 19th century, I think.
But in the 19th century, I think it was mathematical.
So you do it with mathematics first and then after you've understood it that way,
you go back and try and find some intuitive way to weird results that you get.
But it's so easy.
No, no, no. Well, I'm sure I've never even tried.
I mean, the principle of there being places where there is minimal gravity
because there's a sort of cancellation going on, makes sense.
But how on earth you would tell where they were and stuff is way beyond my knowledge of these things.
Yes, I'm going to remain myself.
I mean, I like to say that you heard me earlier.
I said that the forces balance each other was what I said.
But I think some of the forces you'd properly describe as being fictitious forces.
It's your idea of why I called intuition-busting.
Yes, yes.
Are we getting it just centrifugal and centripetal thingies, which are not at least.
Exactly.
Which is fictional, yeah.
Okay.
It feels real when you feel the sort of irony of it.
The forces feel real when you experience them, when you experience them.
So it's actually interesting, right?
The distance, I can't actually see the distance curve elapsed.
I have no idea what that means.
The distance is actually decreasing at the moment.
Oh, no, it isn't. Sorry. What is that?
No, altitude is decreasing.
Ah, yeah, yeah.
There's a plot of distance curve elapsed in kilometers, whatever that means.
Must be projected in the ground, perhaps.
Yeah, altitude is decreasing.
Yeah, I see that.
The graph is tipping downwards away, but it's not here.
To get to the L2 point that they've got to do some sort of bizarre maneuver.
Because it's, what did you say?
It's behind the earth.
It's a point behind the earth.
Yeah, yeah.
So the sun is in the middle, if you think of it that way.
Actually, there's a Wikipedia page about Lagrange stuff,
which shows you a picture of it.
So that's quite useful.
But it shows, you know, the L1, L2, L3, L4 and stuff.
And, yeah, L2 is behind, so it's not clear.
What?
Yeah, I'm not sure how far away it is.
They were talking something about a million miles or...
1.5 million kilometers.
1.5 million.
Okay, fine.
Yeah, I am.
1.5 million kilometers, yes.
Yes, yes.
I'll just correct myself.
It doesn't see distance curve elapsed.
The reason I'm not sure is because the YouTube...
It's right in the limit of the YouTube quality.
Tiny, tiny lettering on the graph caption.
It doesn't make sense, so the graph actually says distance curve elinia.
I think it's French for curve elinia, which means I think it's measuring the distance
along the ground in the earth.
I think...
Okay, okay.
Yeah.
So it could mean it's measuring the distance along the flight path.
Maybe that's what it means.
Perve elinia means it would refer to a distance measured along the curve.
So yeah, that must be what it is.
But anyway, it is weirdly, it is descending at the moment in altitude.
Uh-huh.
Yeah.
But I don't fully understand that, but there you go.
But it doesn't seem from the subtitles I'm reading, but they're all freaked out about it.
Oh, no.
It doesn't seem pretty calm about the whole thing.
So the launch and getting up into...
Well, however, now I'm going to get themselves to L2.
It seems to be going...
If they've separated everything out, the main engine is gone.
So they're just running on the topmost section of the Ariane rocket.
I guess you'd call it, yeah.
So obviously the distance is increasing.
The altitude's going up again now.
So quite what that was about.
I have no idea.
Yeah.
It must have just been an elliptical orbit.
It was in...
In the oil thrust into it and to put themselves into the correct orbit.
It just is altitude.
So the parameters we've got on the screen is altitude distance,
which must be the distance along the flight path.
It was increasing.
Yeah.
And vitesse, which is obviously a freight speeder.
Yeah.
Yeah.
So yes, I have no idea what sort of maneuver is needed to get from French Giano,
which is on the equator they said.
And they go there because they get a bit of a boost from being...
That's one of the fastest points of spin of the Earth.
I think that's the right way to put it.
So...
And then quite what they do, presumably have to orbit partially
and then zoom off from there a little bit in some form or other.
No, no concept of how accurate they'd ever understand that.
Yeah.
Yeah, something like that.
Unfortunately, I was looking at the captions there
and it was talking about an apology.
And I'm pretty sure it wasn't apology.
It meant the word apogee, which means the furthest point from there.
Ah, okay.
But because the subtitles are quite badly translated
and it's not like an entrenched English.
But you know, it's like some kind of machine or official intelligence
in the translation.
It takes words like apology for apogee,
which makes it quite hard to follow what's going on.
Yeah, yeah.
I've turned them off.
Those subtitles are awful.
It gets so many words wrong.
Yeah, everybody extends.
Calls from Karl's star of the mission.
Maybe there's a guy who works
involved in a mission called Karl's star.
Maybe that's what it is.
Yes, I think you just end up not betting much attention
to what's going on because you're translating the subtitles.
So I find it.
It's going to a highly elliptical orbit.
Oh, okay.
And at the moment, yeah.
And at the moment, it must be doing a burden because
it's its altitude is rapidly increasing.
Yeah, yeah.
And it's speed.
This hold is going up as well.
Which, yeah.
So there must be doing a burden at the moment.
You can't have that in normal orbit.
Yeah.
As you, if you're an elliptical orbit,
you got further out.
You would, yeah.
It's altitude decreasing.
As you got further out, you're speeding a decrease.
But it's increasing.
It means they're currently firing the rockets.
Even though I can't see that on the screen.
Oh, you can.
Is it in the bottom right?
It's a little graphic.
Yeah, yeah.
A little animation, as you say.
Right.
Importantly, I've realized that I've,
as well as the thing to you, Dave, earlier,
I've got the T-minus for the launch.
I've got a T-minus for when the turkey has to come up the oven.
And I've just noticed that I've
not put the removing the foil in the right.
It's currently a T-minus
for one hour and ten minutes,
but it should be a T-minus 30.
Yeah, of course.
There are there.
Yeah, you want to do that.
Otherwise, you end up with the rather,
rather wishy-washy bit of turkey, don't you?
It doesn't get to brown and dry out and stuff.
Yeah, I could end up with a burnt, dried up turkey indeed.
Well, true, yeah.
Yeah, that's that as well.
Cool.
Okay.
Yeah, is it worth just...
If we turn this into an HVR show, right?
You think it's worth doing a sort of preamble
to say what JWST is and what it's going to do and stuff?
Because I've been listening to all of that.
You can actually go on the YouTube, I think,
and hear a fair bit, though.
I would imagine they will record that, but I'm not sure.
But maybe we're doing something right then,
and then just cut to our chatting about it.
So, yeah.
Yeah, that sounds like a good plan.
Indeed, because I'll be honest, I'm actually,
despite supposedly being an astronomer,
I actually don't know that much about the details
of the James Webb telescope,
other than, obviously, it's a placement.
It's the next step beyond the Hubble Space Telescope.
Yeah, yeah, yeah.
Well, I listened to a few...
I'm not... I'm no astronomer,
but I listened to a few podcasts
where the astronomy podcasts
and they've been talking a lot about the James Webb.
I've been talking about it for years,
because it's been delayed enormously.
And it's...
So, some people's entire careers have been spent
working on the James Webb,
because they thought they were going to be doing a few years,
and then it was going to be launched,
and they just kept on and on and on developing
or problems coming up and having to be solved, et cetera, et cetera.
But, yeah, so the podcasts are talking about,
what's different between it and Hubble,
and what's going to be used for and all that sort of stuff.
So, yeah.
Yeah.
I mean, I did have the pleasure of working in one NASA space mission,
and I came in fairly late and left the project early.
I was only on it for a few years,
but just as you said,
there was people who spent their entire careers on it,
and there was one chapter in particular,
because it stopped functioning a few years ago,
and we...
Glasgow was one of the universities that had an interest in it,
and so we held wake for it in Glasgow,
when it bit really bit the dust, you know,
I think it's a little bit ran out or something.
Something ran out, which I mean that was the end,
but it didn't function anymore.
We'd be on this desired space mission,
and this was the end,
and so we held a wake for it,
because it meant quite a lot to people's lives.
There was one chapter,
who was probably the...
Sadly, I think one of the main principal investigators
had died by that point.
The other one was getting on a bit,
like the research into his in his 80s.
He was so heavily invested,
and he just couldn't bring himself to attend the wake.
We were refusing to have one over,
and as I got out,
which was just outside Washington,
do you see?
But the Glasgow students had no problem in the French
and Swiss folk over quite a bit.
You know, reluctantly,
we had a little day of talks about it,
and then we just all went to the pub,
and did the proper wake in the pub.
We had so much to do,
but it's the Irish tradition of basically drinking you case
through the clean process
on the day of the funeral.
Yes, yes, yes, yes.
That's a great idea.
Great idea.
It's a fantastic day of the funeral.
I think it was probably on the day of the day.
I think of the person,
and that's certainly how the tradition came about,
because you heard somebody had died.
You know, all pylons in the pub
and started grieving immediately.
Yes.
I think it's got moved to the funeral.
So many cases these days, isn't it?
It's been one or two that was sort of effectively
awake to have a thing after a funeral.
But yeah.
Yeah.
Cool.
So, yes.
Well, I guess you've got a sort of hard stop time,
I guess, you know,
because your cooking programme requires you to be away,
what, what a clock or something like that over earlier.
Um, yeah, I spoke then.
Yeah.
Yeah.
There's some preparations that I need to do.
Yeah.
Basically what?
Yeah.
I don't need to go right now.
That's right.
Yeah.
So, yeah, it does look at that graph
of flight path versus altitude.
It's really climbing quite steeply in altitude.
So, it's, yeah, must be,
it will be burning, burning away in the weekend.
And the graphic, unfortunately, the,
yeah, you can just see the graphics pull has,
the, um, still has the booster firing,
little flame behind the,
um, the spacecraft bit behind the gym,
the telescope.
Um, but it's IS, yeah.
It's sort of pointing towards the camera for a bit there.
So, you didn't receive it now, you can.
Yeah.
Talking about the upper stage freight,
not flight, but flight.
I assume that means flight,
and that they're all freighted.
Yes.
Yes.
Yes.
The subtype of the road.
So, yes, still accelerating.
I think it's 9,
966.
What?
What is that?
9,67 mean.
Uh, it's late,
9.6.
It's the freight.
Of course, of course.
Of course, of course.
Yeah, it's more points, yeah.
Yeah, yeah, yeah.
I don't like that.
Seven kilometers per second.
Yeah.
Yeah.
That's increasing about every second is going up by 0.01 kilometer per second.
And so it's significantly accelerating.
We don't want that.
And its altitude is climbing,
as you can see from the graph, obviously.
So, yeah.
Yes.
We've fascinated if there's anything that shows the actual trajectory of this craft,
because there was...
What's the mission that's going to mercury in the sun?
That's going around the solar system several times of getting gravitational boosts
from the earth and from Venus and whatever.
And there were various diagrams of this strange path that this thing is taking
all over the place.
Yeah.
Perfect.
I got one.
I got one.
Where the one that went?
No.
Oh, yeah.
That was also weird, wasn't it?
Something coming up in the next year or two,
which is a sun related thing.
It's not the other part of solar probe that's already there,
but there's something else.
There's a European one, I think, that's coming up.
Yeah, I should know this.
I can't think of its name off top.
No, I...
It's gone out my head.
So, the graph said extinction,
which I think meant that's what they turned the engines off.
So...
But then not?
Well, the graphic shows the engines being off.
So, I don't know whether that's what it was.
It seemed to coincide with the extinction point in the graph.
So, strange way of putting it.
We turn the ends off here.
You can see that altitude is still increasing.
So, it's now...
We're just over 1,100 kilometers in altitude.
But speed is now decreasing, which tells us that the burn has stopped.
No gravity is accelerating it.
Yeah, and also there's no graphic of the engine firing anymore.
I'm sorry.
Well, the engine...
Yeah, there's the graphic there, but the engine is off the line.
I can't see the graph with this.
No, I didn't notice.
I didn't notice.
Lumpur suggests that the engine is not firing now.
Yeah.
I did notice that the graphic showed the engine stopping
a few minutes ago.
A few seconds probably.
It goes...
The hexagons there, no?
Do you think...
Yep, they're part of the middle or part of the middle?
Yeah, they are.
Those are the panels.
Those are brilliant panels, which have been created as sort of integral pieces.
So, the way to put it, they have cast them or made castings
and then mill them to the specification.
So, they're brilliant hexagons.
We have a gold layer on the top.
And they're using gold because of its reflectance, which you say, in relation to infrared.
It's an infrared telescope.
So, the telescope is now detached from the...
Oh, and everybody is very, very excited.
Of course, that's all clapping.
Yep, yep.
That must mean that that's the...
That must be a few moments for them.
Yes.
You know, I think...
So, there's anything that's going to explode and go badly wrong with that?
Yes, yes.
It's been averted.
Yeah.
So, the final stage has sheltered it to where it needs to be.
Now, it can zoom off by, yeah, all the tool mechanics and whatever to the L2 point.
So, how does it?
Yes.
Because it will have sort of positional rockets on it, I would imagine.
So, I'm sort of on to it because...
Yes, it must.
I mean, when you...
It will orbit in the L2 background points.
It's a bit like orbiting, you know, a mass.
You're going to orbit around the L2 point.
It would be impossible to just sit at it.
So, it will have to enter orbit and to have to decelerate again, I would think.
But maybe, actually, because the L2 point behind the Earth, a lot of the deceleration is done
by the gravitational color of the Earth.
Yeah, I can see even more.
I could fuel that way.
I imagine.
Yes.
Because there's just a telescope and I imagine just positioning thrusters left on the telescope itself.
Yes.
That's what I was trying to say.
It's the right turn.
Yes.
So, it's going to be moving itself around a little bit.
But mostly, it's going to be sitting there with its Sun Reflect pointing at the Sun.
And telescope looking out because it's orbiting the Sun.
The L2 point is moving around the Sun, isn't it?
It will be looking at the entire, well, universe, I guess, as it's moving.
Actually, the images on the screen just now are not graphics.
They're actually camera footage from the booster, although it's just detached from.
It's realised that.
That's exciting.
And the solar panels are unfurling.
Look, can you see that?
Ah, yeah, yeah, yeah.
Oh, my goodness.
Yes, it's quite interesting.
You can see the cover of the Earth.
And I don't know if it overexposed at the moment.
And yeah, the solar panels are reflecting the Sun in a crater.
Yeah, that's a little bit overexposed just now.
Yes.
Wow, that's actually a real footage.
That's a lot of things.
That's amazing.
Yeah, yeah.
It's going to be in an inaccessible place, isn't it?
A Hubble world's accessible.
So that's how there was a mission over there, and fixed the mirror.
Whatever, whatever.
I did, I'm not sure what they did, but they had been grand, wrong, or something.
But, yeah, this one, anything goes wrong with that, that's the end of the story.
Oh, that's amazing.
It's been a one-way trip for a space shuttle.
I wouldn't be able to, even if we didn't have space shuttles,
it would be you wouldn't be able to get back.
No.
No, it's not.
It's because too damn far.
But, yeah, so yes, the hexagons are part of the mirror.
So it will actually open out to produce a sort of circular array of hexagons
with the hole in the middle, where, is that where the camera is?
I'm not sure.
The camera is on a boom of the top of it, or the actual optical pickup point type of thing.
It will be that one too.
Yeah.
Well, actually, I don't know when to look at the design of the telescope,
but also the hexagons.
We even have some big ground-based optical telescopes that are made up of hexagons now,
because to make one big contiguous mirror, I think the Russians tried to do it.
The biggest telescope in the world for a while.
The problem is, when you get to that mirror, it's so massive.
When you tilt it, look at different parts of the sky, it starts to deform,
and obviously that's not on.
No, no, no, no.
You can't have the mirrors deform, but you can slightly.
So the hexagons allow you to pack it up for a space flight,
but also when you can control the shape of the mirror as you tilt it around
in the office, but in the space, I guess, the packing up aspect that's more valuable.
I think that there was some talk which I didn't fully understand
about how the individual hexagons can be moved independently upon another,
and that might be of use in some context.
Because they're actually going to be looking, they're going to be looking at things like Europa,
and try and get really detailed views of Europa and type them.
And they're also going to be checking out comments.
But they're also going to be looking into the deepest possible space,
maybe on what Hubble could see.
Yes, well, on Earth, you call that, that technology you referred to,
maybe able to move the mirrors very precisely, and quickly move them.
What they do, they call it adaptive optics.
You can actually jiggle the mirrors around very quickly to compensate for the seeing,
which is the motion, the twinkling actually, the motions on the Earth's atmosphere,
to distort the image.
Of course, that isn't a problem for the James Webb telescope.
No atmosphere, but there must be something else,
something, maybe to do with interferometry, you know, waving.
Yeah, I'm not sure.
They're going to be doing some very detailed spectroscopy.
Is that the right word?
Of course, they're going to be looking at exoplanets,
with a view to detecting the atmosphere of these things.
So the part of the program is to look for potential planets,
planets with potential life, or potential, you know,
when water seared to methane, et cetera, those sorts of things,
and they have designed it, so they will be able to spot this
by a spectroscopy using the light of the star
that the planet transits.
That makes sense?
Yes, yes.
So what you do there is you look for a spectroscopy,
you look at spectral lines of the star,
and you'd see them juggling backwards and forwards
because of the Doppler effect,
because although the star is doing most,
sorry, the planet is doing most moving,
the star has to move slightly as well,
and that's how we detected our first potential planets.
Yes, yes.
We've seen that the star was juggling around.
Yes.
Due to the effects of the planet orbiting the star, which is...
I think at that point, I need to sign off Dave.
Yeah, no problem.
That was good fun.
Yeah, thanks for that.
Enjoy your Christmas and have a great turkey.
Yes, thanks.
See you soon.
Yeah, okay.
Speak to you soon, cheers.
Righto.
Bye-bye.
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