There’s a bit of tension in the story for this video.

When I put out a call for interesting things that I could film in England,

one of the team from Jodrell Bank got in touch.

Tucked away in the Cheshire countryside,

it’s the home of the Lovell Telescope, a World Heritage Site,

the largest radio telescope in the country,

and one of the scientific and engineering icons of Britain.

And the tension is this.

They wanted to show off the new science they’re working on

all across their campus,

and we are going to do that, ’cos one of the big questions I had was,

is a 70-year-old telescope still useful?

But also, from my side, what I wanted very much

was to climb the giant telescope.

(bird twitters)

Well, there are definitely worse views than that to start the day, aren’t there?

There is a reason for that,

beyond my just being a massive nerd,

when I was young, probably about ten years old,

I went to Jodrell Bank as a visitor,

to see what was then called the Discovery Centre,

not on a school trip.

Young me, very much into space and science,

wanted to go see the big telescope.

But of course, they don’t let visitors onto, or even up close to the telescope,

it’s a working science thing.

And while I had a good day out,

I think I was a bit disappointed that I couldn’t get under it or...

up on it.

There’s no photos of that trip, by the way, it was the nineties,

people didn’t carry cameras around every minute of their lives.

Anyway, about 30 years later, I went back.

Adult-me parked up, checked in with the team at Jodrell Bank, and first up,

they took me to see the newly-updated visitor centre.

There’s a lot of screens and displays,

it’s far more impressive than it used to be,

but I was quite glad to see there were still a couple of things I remembered.

Do you still have the black hole table?

’Cos I remember... -If you just go round here...

You still have the black hole table!

I spent like 15 minutes as a kid just playing with that black hole table.

I was really tempted to do that again,

but never mind.

Also, the old acoustic dishes are still there!

What you’re about to hear is the audio from the on-camera mics, by the way,

no trickery.

I have such a strong memory of these from when I was like ten years old.

(sotto voce) You can whisper very quietly...

And it turns up on the other side.

Core memory. Got to do that again 30 years later.

It’s not bad.

I couldn’t find the mock control room

where kids used to be able to sit down and pretend they were controlling the dish,

but still, happy with that. Nostalgia complete, on to the science.

Now, there are two sides behind the scenes at Jodrell Bank these days.

I did remember seeing the old university buildings from the ’60s and ’70s,

but in the last few years, there’s been a very shiny new headquarters built

next door for another project.

The Square Kilometre Array Observatory, the SKAO,

is a big intergovernmental organisation.

The actual telescopes are on the other side of the planet,

in South Africa and Australia,

but the headquarters is at Jodrell Bank.

I met William, who’s their director of communication, outreach and education,

and the first thing we went to seemed almost out of place.

That’s a very sci-fi sign, isn’t it?

You’ve picked a full science fiction font there.

Okay, you have a proper council chamber!

Well, so, that’s, you know, right there in the middle of Cheshire.

That’s quite unusual. -Yeah.

It’s an unusual setting.

Big picture, what is the SKAO?

So, maybe, you know, you should turn around, and this is the SKAO here.

You know, all these flags. -(laughs)

Oh, I can see why you’re head of outreach. That was smooth.

But this really embodies who we are as an international organisation.

What we are doing is really to build and to operate

the world’s largest radio telescopes.

And one will be observing lower frequencies,

so that’s the one in Australia.

That’s the one we will be using to really go back in time

to what we call the cosmic dawn.

The Cosmic Dawn, as in D-A-W-N,

is the period just after the Big Bang.

And by “just after”, I mean a quarter of a billion years,

because the numbers you encounter in astronomy are mind-boggling.

So, really observing, you know, these very first signals

which were emitted after the Big Bang.

And so, that will give us some clues about, you know, how all of it started.

We know that Nobel Prize discoveries will be made with our telescopes.

When? I don’t know, but, you know, that’s the goal.

I got to talk to their head of science operations.

One of the cool things about the SKA

is really that we’re building it

to be as flexible as possible to observe things that we don’t even know about yet.

We don’t know what our galaxy really looks like.

I mean, it’s quite bizarre to think about the fact that...

Do we not know that?

With all of the beautiful images of other galaxies out there,

we don’t really know what our own galaxy looks like

because it’s quite hard to observe.

-Yeah, you don’t have a mirror out there! -Exactly.

We don’t actually know how big stars form,

and when you’re talking about understanding galaxies

throughout the universe,

I mean, if you don’t understand how those building blocks are really being formed,

then how can you really know the detail of what’s going on in the galaxies?

I mean, how planets form. -Yeah.

I mean, we know that they form in the debris disc around stars.

But we actually don’t know the crucial phase of how things get from

really, really small particles through the centimetre scale

up to something that’s much larger, of course, to make a planet.

We just assume it happens.

It must happen.

-Yes. -We just don’t know how.

We know it happens, but our theory currently doesn’t support it.

And the SKA is really well-suited to that scale.

A lot of things that I assumed were pretty much proven and sorted

are still promising theories with data attached.

The SKAO is going to produce about a petabyte of science data every day

to help with a lot of astronomy.

But while that’s all coordinated at Jodrell Bank,

the actual receipt of signals is happening in other countries.

Because one of the problems with any radio telescope in the UK

is there isn’t much room for radio quiet zones.

And certainly not this close to cities.

Jodrell Bank does ask visitors to turn their phones off,

but there are still roads and train lines nearby, there will be interference.

So I still have the question...

is the Lovell Telescope, the famous one, still useful?

Or is it now more history than science?

To start answering that, I got taken into the telescope control room by Simon,

he’s a professor and the associate director of the observatory.

Five years to build?

Very rapid project, enormously ambitious in the early 1950s,

not long after the war,

to build a radio telescope

which was so much larger than anything that existed before.

How much?

So, it was ten times larger than the largest telescope that existed before.

Oh, okay. Right, sure.

And a leap in the dark.

They had no idea what they would discover.

There were big telescopes before

what became known as the Mark One 250-Foot Telescope,

they just weren’t steerable.

To this day, the big dish at Jodrell Bank

is still the third largest fully steerable telescope in the world.

It can be pointed at anywhere in the sky.

I cannot tell you how much the young version of me

that sat at the mock control room that the discovery centre had back then

is absolutely overjoyed.

Oh, my word.

(laughs)

So, that is the telescope.

That’s the 250-foot, 76-metre Lovell Telescope.

Pointing straight up,

’cos we’re doing some painting and repair work on it at the moment.

I keep worrying that I’m getting in the way of science here.

And I’ve just realised that this is not an observing day.

There is literally a cherry picker with someone painting the telescope in there.

Alright, so, can I have a look? What’s it...?

So, this is Mirza, our controller today.

So, there’s somebody in here,

there’s a controller in this room 24 hours a day...

Right. It’s a lovely control desk, this.

I know that’s the nerdiest thing I’ve said in a while.

It’s a really nice control desk. -This is the original 1957 control desk.

-Right. -In terms of the steel.

But all the electronics that drives the telescope

and controls the telescope so precisely is new.

I am a little worried that, because the folks in that room

were explaining the very basics of their radio astronomy work to me,

I’m doing them a little bit of a disservice.

So, just to be clear, everyone you’re hearing from in that control room

has a PhD.

Anyway, Mirza, the telescope controller,

also showed me a more modern-looking bank of screens at the back of the room,

that connects the telescope to the E-MERLIN network,

a collection of smaller dishes across the UK.

So, you can remote control all of those as well?

We can remotely control from this station here.

As you can see, we have the names of all the telescopes.

You’ll see they’re pointing at the same position,

so they’re all on the same source.

That’s not an icon.... that’s not a static icon.

That’s literally the direction it’s pointing.

That’s live. That’s live data coming through.

You’ll see the Lovell is... -Lovell is pointed up, and it’s red?

It’s pointed straight up, and it’s red.

It’s pointing up, but not in a few hours’ time, hopefully.

Right.

So, you’re observing something right now.

I’m not sure what it is, but you’re definitely observing something.

That something was explained to me by Emmanuel.

Again, PhD.

We are pointing on this particular target, 3C84,

which is one of the brightest radio sources in the sky.

And we use this source as a calibrator

to calibrate the instrument or the observation when it is done.

So, once it stays on this target

for some time in the sky,

all the telescopes will move to the science target

from the calibrator to the target and then observe.

And then once the data comes through the fibre-optics

from all the network of telescopes,

it is correlated right here in Jodrell Bank.

And someone’s going to earn their PhD off that,

or someone’s going to find some magical discovery.

-You never know. -You never know.

One of the advantages of radio astronomy is that scientists can take signals

from telescopes that are a long way apart,

correlate them all together with fibre-optic cables and computers,

and end up with the equivalent resolution

of a telescope the size of that entire network.

This is the ends of those optical fibres.

So, these optical fibres stretch out to the individual telescopes,

and then we have to focus them,

and we do that in the machine which is behind us.

Oh, there’s a...

(laughs)

Okay, you’ve got...

Oh! Okay.

Yep.

(whirring)

Little bit noisy.

So, this is the supercomputer which is doing the focusing.

It’s a correlator designed to multiply the raw signals

from each pair of telescopes,

accumulate those,

and then Emmanuel and colleagues turn those into images.

And the reason it’s in this rather weird room

is that this keeps any of the radio signals that this generates

away from the big dish.

So now we can go and see some of our young scientists working on the data.

The young scientists in question

all either have their PhDs or are working on them.

Sorry to interrupt.

I’ve been told you’ve all been briefed on who I am and what I’m doing here.

I’m worried that Simon just kind of opened the door and said, “Hi, here’s Tom.”

Benjamin is working on a live feed from the 42-foot telescope,

one of the other smaller dishes at Jodrell Bank,

which is picking up the signal from the rapidly rotating remnants

of a collapsed star, called a pulsar.

I have an animation of what one of those looks like here...

Someone has prepared a presentation here!

Simon’s been doing hard work here.

Thank you, folks.

So what we’re seeing here is a beam of radio emission,

a little bit like a lighthouse that is sweeping itself around the sky,

and the reason it sweeps around the sky like this is,

I actually have a little model here.

You have a model!

I knew you were coming.

As the star rotates, that beam,

that radio beam, like here that’s coming away from the magnetic pole,

is sweeping around the sky somewhat like a lighthouse.

And if we happen to be fortuitously located in the galaxy,

and that beam sweeps across Earth,

we will see a little pulse every time it does so,

and so we call them pulsars.

A pulsar is the size of a city, the mass of the Sun,

and the fastest one we know of rotates 716 times per second.

Like I said, astronomy includes mind-boggling numbers.

The idea really is to unambiguously account

for every single rotation of these stars.

Right.

Because if we can do that, then we can do all kinds of experiments

because what we have is effectively clocks in the sky,

and if you have clocks in the sky,

that’s a fantastic way to test general relativity

to find the limits of Einstein’s theory.

Next up is Phoebe, who was bouncing radio signals off asteroids.

So, there’s a radar in Madrid that’ll be transmitting,

and then all the radio telescopes in this network

will then be listening to the echo of that radar pulse,

like, bouncing off the asteroid. -Wow.

And you do that a few times, and you can work out how fast it’s moving,

what direction it’s going, everything like that, or...?

-Hopefully, with just one observation. -Just one?

With the multiple telescopes at the same time,

you should get an idea of the speed from that as well.

Resolution is much better than optical.

We can get down to about a metre,

sort of, with the imaging that we’re going to do.

Hopefully.

This is, sort of, quite new, and we’ve not tried it before.

This is the first VLBI observation

to get this level of detail.

VLBI there is Very Long Baseline Interferometry,

which is the name for that process of combining multiple telescopes

in different locations.

I mean, do I just ask what everyone’s working on?

Like, I’m assuming Simon has prepared all of you with something, but...

Uh, no. This is my regular office.

Okay! (all laugh)

Thank you!

That was a little unfair to Justin,

who I later found out specialises in researching cosmic rays

and high-energy particles,

and was actively working there. I’m sorry, Justin.

But all this research is based on data coming in from other dishes.

We still haven’t talked about the Lovell Telescope itself.

My question remains...

can a 70-year-old telescope still be useful?

Or is it just a heritage landmark now?

Because it has a huge amount of heritage.

Perhaps most famously, it intercepted photos

that were transmitted from the first Soviet lander on the moon.

Those pictures were in the British press

well before the Soviets ever wanted them released.

[announcer] The Western World had their first word of the successful probe

from an English source.

The Jodrell Bank Observatory near Manchester.

It was now time to head out to the telescope itself,

while the maintenance teams were also out there,

and I wasn’t disrupting science.

I put on a climbing harness...

(harness clips and zips) Yeah, alright.

...and then went out to the dish, accompanied by Simon,

plus telescope supervisor, Phil,

who’s worked on the site for decades,

and also, hastily-recruited and quite excited, Megan,

one of Jodrell Bank’s comms team,

who was very happy to volunteer to hold another camera.

Lead the way! Thank you very much.

Oh, shades.

Definitely going to need them.

I’ve never encountered safety sunglasses before,

but when you’ve got not only the sky,

but also the sky reflected off the bowl of a bright-white telescope,

they’re a good idea.

I thought razor burn was just a part of life

that I had to deal with.

But recently, I have unlearned a bad habit

and it’s got better.

I used to instinctively push down when I shaved.

Most folks who shave do that without even thinking about it,

because most modern cartridge razors are built with pivots or springs.

Or if you use disposables, like I did,

the whole thing just flexes a tiny amount.

Because the blade can move, it feels a little unstable

when you're shaving and it meets the resistance of your hair.

It tugs. So you push just a little harder

to try and stabilise it against your skin.

That doesn't actually stop the blade flexing.

It just increases friction, and that’s one of the causes of razor burn.

Just bad design.

A few weeks ago, Henson Shaving sent me their razor.

It’s machined out of solid aerospace-grade aluminum,

the tolerances are as tight as 13 microns in places,

the blade is held completely rigid.

Which means I had to learn not to apply so much force, and

let the weight of the razor do most of the work.

And now I have less razor burn!

There’s no subscription model or proprietary blades here:

this takes the inexpensive, international- standard, double-edge blades.

If you want to use a different brand of blade, you can,

so it also works out much cheaper long-term.

If you use the link in the description or scan the QR code on screen,

you too can get a Henson razor, hopefully end up with less razor burn,

plus they’ll throw in a hundred free blades,

which should last you a long time.

It’s still impressive.

It really is.

3,000 tonnes, able to move from one part of the sky to another fairly quickly,

but also able to track things across the sky

to within a thousandth of a degree.

And that’s a challenge now.

It was a challenge in 1957... -Right!

...before computers! -(laughs)

I came here as a kid,

and remember looking up at this when I was about this tall,

and wanting to do this.

Where do we go from here?

-We’ll head up towards the lift. -Alright.

We just take care stepping over the rails, you can see they’re quite oily and greasy.

Oh, okay.

And we don’t want greasy boots to go climbing with.

Oh! Yeah.

So, are these railway tracks?

Yep, standard railway tracks.

Huh!

That makes sense, because it was built, what, 70 years ago?

And you use the technology you have, if it works and it’s proven.

It’s about 50-100 tonnes per wheel, is the load.

-Yep. -64 wheels it runs on.

-(exhales) -So...

-How on earth? -When you change the wheels,

you jack the telescope up.

Yep.

-Really? -Yep.

So, yep...

Just a hydraulic jack.

-Wow. -About 200 tonnes to lift it up.

Slide it out and put another one in.

The telescope is named after Sir Bernard Lovell,

first director of the observatory,

the driving force behind building the telescope.

And the painting job is apparently never-ending.

You can see the blue cherry picker in the background there.

It’s a steel structure, it relies on painting to protect it.

And, you know, it’s been operating for nearly 70 years,

and we want to keep it going for another 70 years.

Bit cosy, but it does take four people.

(laughter)

And as we headed out onto the catwalks,

I was a little bit lost for words.

(laughs)

Oh, wow!

-You okay? -Yeah!

This is very, very cool.

We didn’t check that you’re okay with heights before coming up here, did we?

(laughs)

Megan was absolutely fine with heights.

Also, you can see two of the other, smaller Jodrell Bank dishes there,

those were the ones actively listening and doing science at that moment.

From there, it was up onto the first surface of the dish.

The telescope does look a bit different compared to the early days.

It’s been shored up and upgraded over years,

and it gained a brand new surface in the early 2000s.

Oh!

The first stop was between those two surfaces,

and then it was up onto the dish.

(laughing)

Thank you!

The telescope’s been standing for 70 years,

this floor has been standing for 25 years,

and it’s made of steel, and yet,

somehow I’m still just a little bit worried as I go up here.

So, the idea of the parabola is to focus the radio waves that land on the telescope

to the focus, which is what you can see at the top.

Yes, because there’s all sorts of bad graphics

where the beam is coming into that directly,

and it’s not, it comes into this bowl...

-Yes. -...and gets bounced up to there.

Yep.

And the property of a parabola is, wherever it hits this surface,

it ends up in that hole in the middle.

And moreover, the path length from each ray is the same.

So, if you like, all those radio waves add up coherently, in step, at the focus.

-Oh! -That is the property of a parabola.

Right.

Radio has a wavelength anywhere from a few centimetres to kilometres,

so thankfully, the dish surface doesn’t have to be too precise.

We’re not going to cause any damage walking on it.

To see nothing but dish and the sky is magic.

Okay, if you’re ready for the next challenge,

we can have a go at heading up to the top and have a look.

Yeah, this is where I leave you two behind.

Let’s do it.

And the sun’s come out!

And it’s blinding!

You were right about those shades.

I’m going to put those on.

I know, I look like a dork...

Oh, my word!

...and you can’t see my eyes.

I take the shades off again in a bit,

but with the sun out and that light being reflected up towards us,

it was bright.

There is a reason that you do not point a telescope at the sun.

Even well off-axis, like it was, it felt so bright.

But we were high enough that I could see the horizon again.

I am so incredibly lucky. Right.

Where do I go from here?

Climbing harness hooked in,

up the ladder to the focal point.

That is the very top of the telescope.

(laughs)

Oh, it wobbles!

Course it does.

What an incredible view.

Something special, isn’t it, up here?

It really is.

So, is it still doing science?

I don’t know what I was expecting.

Some mirror system, some fancy little thing?

No, you’re literally moving the entire detector.

Yep. Because there’s only one focal point to the whole dish.

So, to use that same focal point twice... -Yeah.

...it requires to move one out of the way and put the other one into the same slot.

The telescope is 70 years old.

It’s now a Grade I listed historical site,

which is probably going to give them all sorts of trouble

refitting it in future.

But the surface is only 25 years old,

and those multiple detectors, the different science packages

that can be moved into the focal point are much more recent than that.

The Lovell Telescope is still doing world-class science,

on its own, as part of networks,

because it turns out that as long as you do the upkeep,

the scientific concept of

“massive parabolic dish that you can point anywhere”

doesn’t really go out of date.

But there is one more thing.

I spent a while admiring the view,

and then headed back down, and back in the control room,

I got to do something that my ten-year-old self,

playing at the controls in the mock control room in the discovery centre,

would never have dreamed was possible.

Alright.

Five seconds on the siren?

Five seconds on the siren, yes.

(siren wails)

(siren fades)

That got their attention, right? And then...

Return.

-Enter on here. -Yeah.

With slow grace,

the Lovell Telescope began to turn

and pointed at its first science target for the day.

There’s a kid, um, on the fence there,

he’s going to be, like, a few pixels in the final footage.

And he’s just staring up at the machine,

and he’s about the age I would have been when I got here.

I wonder if the same thing’s just sparked off in his head?

(chuckles)

The ten-year-old version of me is so happy.

Your dream’s come true.

Next time, or right now on Nebula,

I visit a school where the students have four legs

and a bendy backbone, to see how they outperform robots.