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00:01Nestled in the Cheshire countryside stands a landmark so vast it can be seen from the Welsh
00:07hills nearly 60 miles away and for 80 years it's played a crucial part in both science and in world
00:15history. It's part of a site that played a leading role in the birth and then the development of a
00:21whole new way of looking at or rather listening to our universe but it also played an important
00:27role in top-secret military intrigue during a period of terrifying world tension. It's one of my favourite
00:34places in the world. This is the magnificent Lovell telescope at the heart of Jodrell Bank.
00:40Welcome to the Sky at Night.
01:14I'm always excited to be here at Jodrell Bank. Every time I visit that first glimpse of the enormous
01:20Lovell telescope looming over the countryside still thrills me just as it did when I first came
01:26here 25 years ago. Once not much more than fields the site has been transformed into a world-leading
01:34centre for radio astronomy. Traditionally astronomers have used the familiar optical telescope to collect
01:41visible light the kind of light your eyes are sensitive to and used it to tell us what objects
01:46look like out in the cosmos. Radio telescopes are built to detect radio waves still light but with
01:53a much longer wavelength. Invisible to the eye this radiation from distant sources can be detected by
02:00equipment that apart from scale isn't that different from a satellite dish on the side of a house.
02:07But it's not Friday night telly they're listening out for. These giant dishes are detecting faint radio waves
02:15that have travelled millions of miles across space and which can reveal the secrets of some of the most
02:20distant and powerful objects in the universe. And it all started here 80 years ago.
02:27On a winter day in 1945 a physicist with a trailer full of equipment drove into a field nearby.
02:35What he wanted to do is observe high energy particles in the earth's atmosphere. What he eventually
02:41divert put the UK at the forefront of a new kind of astronomy and at the very heart of the
02:47space race.
02:51The man was physicist Bernard Lovell who wanted to turn his wartime work with radar to the skies above.
02:59He borrowed equipment from the army and took it to a quiet spot used by the University of Manchester's
03:05Botany Department where he intended to stay for just two weeks. Tim O'Brien one of the directors of this
03:12site can tell me what happened next.
03:16Bernard Lovell first came here in December of 1945. The only people here there were two gardeners who worked in
03:22botany
03:23and a couple of local farmers. He tried to get this radar kit working couldn't get it to work.
03:28One of the farmers pointed out that the fuel, the diesel, was frozen in the generator. So they helped him
03:34get it working,
03:35sending these radio pulses up into the sky and sure enough the echoes returned. But rather than being
03:41from cosmic rays it turned out they were from meteors, they were from the trails from shooting stars.
03:46And it was actually that that turned Lovell into an astronomer and made this an observatory.
03:54So he knew nothing about astronomy. So in fact he got the person called Manning Prentiss, who was a solicitor,
04:10but a leading light in the amateur astronomical community. And actually they realised that to study
04:15more about these radar echoes from meteor trails they needed something a bit fancier than the radar kit
04:21they got from the army. So actually he returned to the army and he said can we borrow a such
04:26light.
04:27And it wasn't the light they were after it was just purely the mount. And so what they did was
04:32they
04:32put it in the field just over there and they strapped all these scaffolding poles to it and basically
04:39made a whole bunch of aerials on it and they used it as the base for a radar aerial which
04:46they could steer
04:46around and study the meteors. OK so what did they find with the meteors? They studied various meteor
04:52showers during 1946 from this field and in the October of 46 there was a massive meteor storm of
04:58the Jacobinids and they got loads of data on that and they were invited to go down to the Royal
05:04Astronomical Society in December of 1946 to talk about the results. And this was very strange right
05:10because they were coming into this environment that was absolutely not used to looking at signals
05:15with dials and things. You would be looking through eyepieces or taking photographs. And Lovell actually
05:20said he said we went into that meeting as if we were sort of aliens infiltrating some privileged
05:26community. Yes. But they left as fully fledged astronomers. So I guess radio astronomy was born?
05:32Radio astronomy was born at that point yeah.
05:36Having established a new field in radio astronomy, Lovell turned his sights to a new dish. Completed in 1947.
05:45The transit telescope was made of a fixed mesh, 217 feet across. And it was soon furthering the case
05:53for radio astronomy. So they built this giant ball. It couldn't tip or turn. It just looked straight up.
06:03It had a pole in the middle. The radio waves coming from above reflected gathered at the pole.
06:09What they did detect was radio waves from other galaxies. In fact they were the first to detect
06:15radio waves from another galaxy, the Andromeda galaxy, the nearby galaxy.
06:18So we have radio astronomy. You've got this big dish but it's not steerable. So then what comes next?
06:24The next thing was this ridiculously ambitious idea that they needed something at least as large but which
06:30could point to any part of the sky. And that's over here. Over this way, okay.
06:37What Lovell was proposing was the largest steerable telescope in the world.
06:42A crazy ambition at the time and one that some said just couldn't be done.
06:48Nobody had ever done anything like this in the world before and it took him a long time to get
06:52an engineer to agree to help design it with him. And he finally found Charles' husband at the end of
06:57the 1940s, just early 1950s, and he was prepared to take on the task.
07:01Wow.
07:02I mean, husband sort of felt he was a bridge builder so he thought, well it's the same sort of
07:05design as a big suspension bridge or something. And in fact it looks like it's very Victorian sort
07:11of engineering riveted together. They had to build and design a specially designed railway track
07:17with railway bogies on it that turn it around. Up in the tops of the towers actually you've got
07:24another bit of army surplus equipment. The whole bowl of the telescope tips on gear racks that came
07:33from the two 15-inch gun turrets from World War I battleships. So he's still pulvering stuff from
07:40the army and the navy. Absolutely. Yeah. And those battleships had been in World War I. They'd been
07:44used in World War II and they were being broken up at the end of the war and they thought,
07:47well this
07:48is a handy bit of steel work. We'll take this for our telescope. And it's still there now.
07:53So looking at the construction, it started in 1952. How long did it take?
07:58It took five years but in the summer of 1957 there was no money left to pay the workers
08:03on site so they were on strike. Lovell was, there were serious questions being asked about the cost
08:08overruns. It really looked like the project would fail and Lovell's phrase was he turned to one of
08:13his colleagues and he said, you know we need a miracle to save us. Yes. And that miracle did actually
08:19happen. Oh yes. The miracle was the launch of Sputnik 1, the Soviet satellite in October of 57.
08:25So how did this dish play a part in that? Lovell got a phone call from someone in a branch
08:30of
08:30government that said to him, we'd like you to try and use a radar on that telescope,
08:35not to detect the satellite but the rocket that carried it into space that was also orbiting. And that
08:41rocket was an intercontinental ballistic missile. The fear was that next time it could be a nuclear
08:47warhead. That of course that drew everyone back in so within less than a week actually they got the
08:53telescope to point north and see this rocket as it flew over the Lake District. The fact that the
08:58telescope tracked that rocket was effectively what saved the day as far as Lovell and as far as the
09:04observatory who was concerned. Yeah, so saved by the space race? Indeed, saved by the space race.
09:11And it was the space race that led to a very secret role Jodrell Bank played during the second half
09:17of the 20th century. As Chris has been finding out. As the 1950s gave way to the 1960s, the Cold
09:26War
09:26threatened to heat up. As the Soviet Union faced off with the United States, the entire world lived under
09:32the shadow of nuclear annihilation. And Jodrell Bank had an unexpected role in their high stakes
09:40competition. The University of Manchester holds previously top secret files relating to this era.
09:50And I'm lucky enough to be getting a look. Danielle George's dual identity gives her a special interest
09:57in these documents. Tell us about your connection to these worlds first. Yes, so I was at Jodrell Bank
10:04in the 1990s, became a professor of radio frequency engineering and I'm currently the chief scientific
10:10advisor for national security for GCHQ. So this is a great story for me because it feels like it's
10:15sort of come all back around to where I started. Well, you're the perfect person to tell us about this.
10:20So I think people maybe know that Jodrell was able to track the rocket that launched Sputnik,
10:24but there was much more to this connection than that. Yes, so Sir Bernard Lovell at the time had
10:30this really curious relationship with GCHQ. The first thing I want to show you here... Okay,
10:34these were classified, so some of them say secret on and things like this. Yes, so they've just been
10:39declassified quite recently. And this is the first one I'll show you, is this private telephone network
10:45to Jodrell Bank. Oh, okay, so that they could connect. From GCHQ, so what they called Lab 5.
10:50This is actually the card, just to show the telephone card. Oh, so these are the different
10:57connections? Yes, so you're like literally circuiting through the country, Cheltenham to
11:02specific areas. Okay, but they have this sort of private line connected. It already feels very spy.
11:07It does, yes. Yeah, yeah. Those secure phone lines would have been crucial as Jodrell Bank secretly
11:15tracked Soviet movements, including the historic moment in 1966 when they monitored the first ever
11:23controlled landing of a spacecraft on the moon's surface. The next one I want to show you is the
11:29Lunar 9 mission. This is the Soviet mission. It was a soft landing on the moon with an idea to
11:36then
11:37take pictures of the lunar surface. So, Jodrell Bank knew about Lunar 9, they were tracking it and then
11:43all of a sudden the transmission stops and they're like, oh my goodness, maybe we've lost the
11:49transmission. And then it starts again and JG Davis at the time says, I think they're transmitting
11:55pictures, images. Well, how can we get these images? Yeah, because they're recording what
12:00they're receiving, so they've got it on tape. Exactly. They eventually sort of say, who has
12:04something like a facsimile machine precursors to fax machines? So, they call up the Daily Express,
12:09say, hey, can we borrow one of these sort of fax machines? That then gets shipped out to Jodrell,
12:15but then they're able to print these images of the lunar surface. And this was just incredible.
12:22Yeah. So, you can imagine from a scientific perspective, you know, how Lovell and others
12:26must have felt seeing these images. These images were the very first taken from the lunar surface.
12:34And unbeknownst to the Soviets, Jodrell Bank had intercepted them. And there's this letter here
12:40from, I think, GCHQ about the Lunar 9. This is from Leonard Hooper, who was the director of GCHQ
12:46at the time. They actually sent them the intelligence report. So, this is quite interesting,
12:50this sort of relationship. It is going both ways. Yeah. So, there's a sharing between them.
12:54That's right. And then he says here that, you know, his American colleagues are grateful.
12:58So, there's this thing of involving the US as well. We've got Jodrell,
13:02and so we can give this information. Exactly. Huge asset. Yeah, yeah. Which GCHQ absolutely knew.
13:11As the space race escalated towards humans getting to the moon,
13:15Jodrell Bank was listening and caught voices on a mission that was meant to be uncrewed.
13:21ZON-6 was a Soviet mission, again, another lunar space probe, to take living organisms to the
13:28vicinity of the moon. So, this is not landing on the moon. Right.
13:31This is just the vicinity. And it's not people.
13:32And it's not people. So, this was unpiloted, but it was like a Soyuz capsule.
13:36And we're talking, this is, what, 68. We're right at the heart of the space race.
13:40We really are. So, Jodrell tracked ZON-6, listening to all of this telemetry data,
13:45and then it starts to pick up voice as well. So, we have a recording
13:51from Sir Bernard Lovell on the ZON-6 transmissions.
14:05How's your Russian? Not very good. No. So, these voices,
14:08they're coming from the spacecraft. You can see that from the telescope.
14:11But they're not cosmonauts on board. They're not. Yeah.
14:14But they didn't know where they were as well. So, this letter actually has a translation from GCHQ.
14:23They actually say it is actually the role of a ground controller and the other one is taking
14:28a role of a simulated cosmonaut. So, it was two people on the ground relaying messages
14:34through the spacecraft rather than a recording on the spacecraft.
14:36So, they're testing the communication system. Exactly that.
14:39So, how important was this information from ZON-6?
14:42From a scientific perspective, very important, but from an intelligence side,
14:45really, really beneficial. So, in the thank you letter here from GCHQ, it even says,
14:51the intelligence value of this material is potentially considerable.
14:55And again, the sense, you know, in our field, as well as yours,
14:57Jodrell Bank and its skilled people is regarded as a major British asset.
15:01And so, it's the sense of it's something that Britain offers the West.
15:04Exactly. Yes. Yeah. It is a huge national asset.
15:07Look, I really like this. We understand that pressures may be put upon you for release to the BBC
15:12of these conversations. Sorry.
15:14Yeah.
15:14I wonder what they've made of us talking about it now.
15:17So, how long did this sort of collaboration carry on for?
15:20Oh, a very long time. There are still records well into sort of the 60s and 70s and beyond
15:28from GCHQ and Jodrell Bank. We have offices here in the North West now.
15:32Some I could tell you about sometime. I couldn't. Right.
15:35But the fact that we are growing in the North West and Jodrell is still this amazing,
15:40iconic science facility here in the North West as well.
15:42So, looking through these files, what surprises you most?
15:46I think it's the relationship. Lovell was always very much a friend of the intelligence community,
15:53but quite a curious friend in that he was a scientist as well.
15:56Right.
15:56So, when you have amazing science coming back from these lunar missions,
16:01it's almost like he didn't care if it was Russian or US or whatever.
16:04If there's science part of that, he wants to share that with people.
16:09And that cutting-edge science has carried on over the decades at Jodrell Bank,
16:15with the upgraded Lovell telescope at its heart.
16:20Overlooking the telescope is the control room,
16:25where Maggie is meeting research support scientists, Emmanuel Benpong-Manful.
16:31So, Emmanuel, the Lovell dish is an amazing telescope,
16:36so there must be a lot of competition to get time on it.
16:38Lovell, as I call it, Majestic Lovell, is one of the most sought-after telescopes on the planet.
16:45Astronomers from the UK and around the world can apply for time to use our facilities or telescopes.
16:51And I can tell you for a fact that Lovell is one of the telescopes that many astronomers love to
16:57use,
16:57because of the sensitivity that it provides.
17:01And it's no wonder it's in high demand when you look at its track record.
17:07So, what sort of discoveries is Lovell doing?
17:10Lovell is a groundbreaking instrument when it comes to POSA discoveries.
17:14As at the year 2007, all the known pulses in the world, about 1,700 of them,
17:21three quarters were detected or discovered right here at Jodrell Bank Observatory.
17:26And also a fast radio burst, which is also something at the forefront of modern astrophysics research,
17:32pinpointing or localising where these fast radio bursts are actually occurring in galaxies,
17:37and studying their environments in much more detail.
17:42On its own, the Lovell telescope is an impressive piece of engineering,
17:47but it is also part of a network of radio telescopes linked across the UK.
17:52With their headquarters at Jodrell Bank, they create one of the most impressive,
17:56high-resolution radio telescope arrays in the world, known as eMerlin.
18:01E-Merlin, what is it, and what's its capabilities?
18:05E-Merlin is the Enhanced Multi-Element Radio Interferometry Link Network.
18:11OK, that's quite an acronym.
18:13Yeah, yeah.
18:13So, the network consists of seven telescopes, including the Lovell.
18:18We can observe almost everything you can think of in the cosmos,
18:21from the smallest-scale structures like meteors and asteroids, exoplanets,
18:27all the way to the larger-scale structures like galaxies and galaxy clusters.
18:31So, yeah, this is one of the most powerful instruments currently on the planet.
18:37That power is already providing new insights.
18:41In 2023, eMerlin achieved the first-ever radio detection of a Type Ia supernova,
18:49a class of exploding star crucial for calculating the vast distances of far-flung galaxies.
18:56Long observed, the precise trigger for their occurrence has remained uncertain.
19:01So, eMerlin was able to do a radio detection of this Type Ia supernova.
19:06So, what did it find?
19:07Astronomers were able to resolve the host supernova explosion,
19:11or the star that was hosting this particular explosion.
19:14So, there was a white dwarf with a companion star,
19:18and so they were able to resolve these two components as the progenitor of this supernova explosion,
19:24which is really cool.
19:26Yeah, that's amazing.
19:28This is a huge leap forward in our understanding of Type Ia supernova.
19:33The observations revealed that these stellar explosions aren't created by a single star exploding,
19:39as some have theorised, but more complex models must be at work,
19:43with a second star feeding material which fuels the explosion.
19:47And it's the incredible power of eMerlin that is made that possible.
19:52EMerlin's resolution and sensitivity is unique in the sense that it allows eMerlin to be able to resolve structures.
19:59By resolving structures like see, find details of structures that are as far as 250 kilometres away from us.
20:06So, if you want to look at this in context, then this is almost equivalent to resolving like a £1
20:13coin in London from Manchester.
20:15Wow.
20:15So, if someone was in London holding up a £1 coin, you can literally see that £1 coin from Manchester.
20:24That's how powerful eMerlin is.
20:30While radio astronomy listens out for the signals coming from deep space,
20:34it's going back to Jodrell Bank's radar routes, where signals are sent out and their reflections recorded,
20:40that may give us a new way of studying what's happening just above our heads.
20:46There's currently a global rush to get more and more satellites into orbit.
20:50Everything from mobile phone networks, GPS, to weather forecasting, flood monitoring,
20:56and even tracking animal migrations relies on them.
20:59And keeping track of them all is no easy feat.
21:02But today, the level is being repurposed again,
21:06and its upgraded capabilities can now focus on modern threats from space.
21:13PhD student Phoebe Ryder is using radar to track what's moving above our heads
21:18to protect us from possible dangers.
21:22Oh my goodness, what an incredible view. Is this actually your office?
21:26Yeah, though it's so amazing to get to sit and work and look at that.
21:29Tell me about your research. What are you actually working on?
21:31So, I'm using the telescopes here, including this big one,
21:35to do bi-static radar for space situational awareness.
21:38Normally, radar is monostatic, so the same bit of kit does the transmitting and the receiving.
21:43But we're using these as bi-static receivers.
21:47So, if you don't have to keep switching, you can keep the system temperature a lot lower,
21:50so your sensitivity is much better.
21:52It's also, it's massive, much bigger than any radar transmitter.
21:57So, the main things we're looking at are geostationary satellites.
22:01And so, to get detections, you need something very sensitive to be able to do meaningful work.
22:07And this detailed tracking of the satellites, 36,000 kilometres above us,
22:13is getting more and more important.
22:15Between 2020 and 2025, more satellites were launched than in all previous history combined.
22:23And by 2030, up to 100,000 could be orbiting Earth, each with a limited lifespan.
22:30As failed satellites join fast-moving debris and natural space dust,
22:35Earth's orbit is becoming dangerously crowded, increasing the risk of collision.
22:41But Phoebe's precision tracking could reduce that risk.
22:46There was a communications satellite that exploded about a year ago.
22:50So, we did some detections of some small pieces of debris.
22:53So, I mean, how big a thing are we talking about, and how big are the chunks of debris, do
22:58you think?
22:58So, it's difficult to know that. And so, what we're doing is trying to characterise how big these bits are.
23:03The bit that we observed is, we think, about 65 centimetres.
23:07I'm absolutely blown away by the fact that you are, with a radio telescope,
23:10observing something that's 65 centimetres across. Do you have some data that you can show me?
23:15Yeah. So, this is a little movie showing it moving.
23:18The intensity of the colour is the intensity of the reflection of the radar wave that we're getting back.
23:23Yeah. So, you can see it kind of jittering and moving. And that's because it's tumbling and rotating.
23:29And that's how we can get a size estimate, is by mapping the period with which it flashes again.
23:37This single blip on a screen could be the early warning crucially needed.
23:42One impact could trigger a Kessler syndrome, a chain reaction turning low Earth orbit into a debris field
23:50and cutting off access to space for generations to come.
23:55My question is, because it's exploded, is it kind of stable in that geostationary belt?
24:00Or could its trajectory come inward at some point?
24:03It could definitely come inward. It's not stable at all. We don't know where these things are going.
24:09I mean, there's thousands of pieces of debris from this explosion and this is just one.
24:13So, it's a lot of work to map all of these and to get an idea of what's up there.
24:17So, it's genuinely incredible to see images of something so small.
24:22What do you see for the future? What are your hopes for the future of this technology?
24:25So, the hopes for the future are to use the sensitivity that we've got with Lovell,
24:29but also combine it with observations from the multiple telescopes that are the eMerlin network.
24:35And so, by combining observations from all of these telescopes,
24:38should be able to build up a better 3D picture of the debris,
24:41which will help with avoiding it and making it less of a hazard in space.
24:46While telescopes like the Lovell can give us great insights into the skies above us,
24:51there is much to enjoy purely by looking up.
24:59Pete's on site to guide us through the coming months.
25:03I still don't know where the eyepiece goes. Luckily, you don't need one of these to be able
25:07to view the planets from your own back garden. And over the winter months, the planets have been in
25:12great positions for viewing, when the weather allows of course. Now most are too close to the sun's glare
25:18in the morning and evening skies, but there are still a few out to play.
25:24Both Venus and Jupiter are currently visible, bright and obvious as twilight darkens.
25:31To find them, look towards the west-northwest around 45 minutes to an hour after sunset.
25:38If you repeat this over many evenings, you can see a convergence or moving together of the planets,
25:45as they move around their orbits in relation to us. And from the end of the month, keep a look
25:51out for
25:52little Mercury, which makes an appearance closer to the position of the sun in the evening sky.
25:59While the two planets move across the sky in opposite directions, there's also an interesting
26:05interplay to look out for involving the moon over the next month or so. Watching how these celestial
26:11objects move with the naked eye gives a great sense of the 3D nature of our solar system, something you
26:17don't always pick up when viewing a planet in isolation. Three dates in particular are great to look out for.
26:25On the evening of the 18th of May, a thin 6% lit waxing crescent moon sits near Venus,
26:32a popular pairing for astrophotography.
26:36Then on the 19th, the now 13% lit lunar crescent appears between Jupiter and Venus.
26:45Finally, on the 20th, the 22% lit waxing crescent moon appears close to Jupiter.
26:53Jupiter's movement means it'll soon disappear into the sun's glare until later in the year. On its way,
27:00there's a lovely meeting between it and Venus to look forward to. The conjunction is visible from the
27:06middle of May through to the second week of June. That's assuming we get clear skies of course.
27:12Not only does this present a beautiful thing to watch, it also presents a great opportunity to take
27:18a picture with basic kit like a smartphone, a general photographic camera or a telescope imaging setup.
27:27To find it, continue looking towards the west-northwest around 45 minutes to an hour after sunset.
27:33And by tracking it for as many days as possible, you can see them come together. Until, on the 9th
27:41of June,
27:42they will reach their closest point, with a minimum separation of 1.6 degrees.
27:48This is approximately equivalent to three times the apparent diameter of the moon.
27:53As ever, if you do take a picture of this or of any other stargazing targets,
27:59please send them in to our Flickr account. You can find details at bbc.co.uk
28:04forward slash sky at night. Here are some which were submitted recently.
28:28While Jodrell Bank is a historic site, it's also a monument to decades of scientific effort.
28:34A place where discoveries have been made and are still being made today.
28:38And it's also a pretty fascinating place to visit.
28:41But to me, it's more than all of that.
28:44It's a reminder, a very visible reminder, that we can do world-class astronomy here in the UK
28:50and live up to the dreams of its founders and builders who thought about exploring the cosmos.
28:55Let's hope it can do that for another 80 years.
28:58Good night.
29:05Good night.
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