In this week's show, we speak to a former navy commander about the Titan sub, do our decision-makers ignore evidence when making scientific policy? And the new telescope that is hoping to explore the dark side of the cosmos...
In this episode
Titan sub remnants found
Frank Owen, Formerly of Australian Submarine Escape and Rescue Project
The disappearance of the Titan submersible, en-route to view the wreck of the Titanic, 4 kilometres down and about 400 miles offshore has dominated the news this week. Contact with the OceanGate sub - and its crew of five - was lost on Sunday as it made a descent to Titanic in the Atlantic Ocean. The tail section of the Titan has reportedly been spotted since, suggesting that the sub may have imploded under the intense 400 atmosphere pressure down close to the sunken ship. Chris Smith spoke to Frank Owen, retired navy commander and former director of the Australian Submarine Escape and Rescue Project…
Frank - This was an expedition mounted where they sought paying guests to go down to see the Titanic. We know that the conditions and the planning had meant that there was only going to be one expedition possible this year. There were two planned for 2024 and we knew that the weather had been unsuitable for proceeding with the mission until a window opened up on the Sunday at which time they dived. They lost contact an hour and 45 minutes into the dive.
Chris - And do we know the nature of that contact when we say they lost contact, you can't talk on the phone when you are underwater. So what was the nature of that contact?
Frank - They have a through water information link. It's similar to a modulated wave that passes on a carrier wave which includes some communication elements, so they're able then to pass text messages between some support vessel and the submersible. There are similar systems like that in the military actually.
Chris - So if contact was lost at that time point, how deep would that put them at the point at which contact was lost?
Frank - The whole trip is supposed to take eight hours and you'd imagine they would take perhaps two hours to get to the bottom, four or five hours circling looking at the wreck and then the rest of the time to return to the surface and be recovered. It would probably take longer to be recovered than it would be to be launched, so I would think that they were quite close to their intended depth when communications were lost.
Chris - Obviously communications could be lost just because something has malfunctioned, it doesn't mean that they were in jeopardy at that point, but the fact they haven't returned argues something has gone wrong. When you are nearly four kilometres underwater, what is that like for a craft to have to tolerate and take and what are the currents like? Tell us about the environment at that sort of depth.
Frank - Most of the current is going to be up towards the surface. You've got things like the Gulf Stream going past. It's not immediately in the Gulf Stream where they are, otherwise you wouldn't have a lot of icebergs that were there when Titanic hit it, of course. But it is in an area where you do have surface currents that are moving around. The current down near the seabed would be much less the temperature and in that sort of water column would tend to be perhaps 10 or so degrees at the surface and it'll stay about that temperature until it gets to what they call the layer, which will be around 200 metres. At that point, the temperature takes a sharp drop and within about a thousand metres or so, it'll drop from that 10 degrees down to the two or three and then it'll stay isothermal or the same temperature all the way to the bottom. What that barrier does that break is that it really affects the passage of sound through the water. So sound that comes down to that depth will then be refracted downwards and it creates a barrier underneath this layer where it's very difficult to hear things.
Chris - And I guess that means it will be very difficult to penetrate that layer with the sort of sonar that can explore the sea floor even if you had one powerful enough to get over this sort of distance. Which at the moment most boats aren't endowed with that, are they?
Frank - No, they're not. And really at 4,000 metres you might get an echo sounder telling you what the depth is, but that's a sort of brute force. You won't get an imaging sonar getting anywhere near through that.
Chris - Has anyone ever recovered anybody or anything from these sorts of depths before in your career as a rescue operator? Would this just be totally unfeasible?
Frank - No, it's not unfeasible. The US Navy has recovered vehicles and aircraft from that sort of depth. They've recovered an F 35 from even deeper than this. Once that sort of vehicle is down at that depth, as long as it's within the pressure rating, it can actually then work as if it's doing its main job. The biggest challenge that an ROV faces is the drag because it's trying to drag the umbilical against the current for all of that 8,000 metres. Once the umbilical itself is bent by the force of the current…
Chris - This is the cable and the tether that these remote vehicles that you would seek to rescue with are on back to the the ship on the surface, isn't it?
Frank - Yeah. So the tethers are going to be in the order of a diameter of about 50 millimetres, perhaps more. If you look at the surface area of 50 millimetres by 5,000 metres, you end up with the frontal characteristics of several big trucks. So it's trying to pull all of that weight through the water.
Chris - And these poor people who've been trapped inside this submersible. If one finds oneself in that sort of situation, is there anything you can do to maximise your chances of survival?
Frank - Yes, you can rest. The best thing you can do is lower all parts of your metabolism. So the best thing to do is sleep. If their body temperature really drops down in a way that's a good thing because what will happen is everything will slow down, their heart rate will drop, they won't breathe as much, they therefore won't consume as much oxygen and they won't generate as much carbon dioxide to eke out all of the benefits of the air purification system that they have.
Chris - This sort of mission in this sort of vehicle. What's your reaction when you saw the news and what was going on and who was doing what would you go to sea in that?
Frank - Especially with what I know now, I don't think I would go to see in that craft. It doesn't have the redundant systems and emergency systems that I'm very familiar with, with other vehicles, including the vehicle that we developed in Australia for the submarine rescue system that we had, which had on its roof on the top of the vehicle radar reflector, it had strobe lights, it had radio transmitters, and they would've been used to be able to communicate with searching forces. It also had transponders, or beacons, that could make a ping to alert people to where it's lost when it was diving. So those sorts of systems aren't needed in the day-to-day running of the vehicle, but they're very important when things go wrong and I don't see evidence of them in the titan.
08:06 - UK Gov commitments don't stand up to scrutiny
UK Gov commitments don't stand up to scrutiny
Dame Theresa Marteau, University of Cambridge
A top public health expert at the University of Cambridge has said that efforts to tackle major issues facing the UK - including the nation’s health and climate change - are showing a gulf opening up between the intended target and the reality. Dame Theresa Marteau’s editorial has just been published in the journal Science and Public Policy…
Theresa - I was struck by the number of laudable ambitions that recent governments were issuing to improve our health and tackle climate change, such as halving childhood obesity by 2030, achieving net zero emissions by 2050, which critically depend on being able to change behaviour at scale. And I was also noticing that there were many excellent reports that were coming out summarising the evidence on achieving the sustained behaviour change that these ambitions depend on that didn't seem to be a featuring in the policies. So I wanted to examine the extent to which that impression was realised when I looked at some of those policies.
Chris - So, targets are being laid down, gauntlets are being thrown down, if you will, but there's no evidence for why, how, or what to do in order to achieve those outcomes.
Theresa - What I do in this editorial is that I look at four current government ambitions to improve the health of the population and tackle the climate emergency, all of which were required to an extent being able to change behaviour at scale. And what I found was that all four of them were off track to varying degrees or predicted to be off track. Halving childhood obesity by 2030, that's possibly the one that's most off track. That seems to be set to double, not halve by 2030. In 2018, 20% of 10 year olds were living with obesity. And in 2021 that figure had gone up, not down, to around 25%. Unfortunately, the rates are much higher for children living in deprived neighborhoods where the rates of 34% compared to their peers living in least deprived areas where it's 14%. Eradicating smoking by 2030. We are making some progress there, but eradicating smoking means having smoking rates of 5% or under, and we're only at 14%. And it's estimated that it will take until 2050 to realise that ambition. Two more ambitions, increasing healthy life expectancy by five years, by 2035, and narrowing the gap between the rich and the poor. Unfortunately recently healthy life expectancy fell by half a year. It doesn't sound much, but the trend had previously been increasing a number of years that we can expect to live in good health. So that had fallen by half a year between 2010 and 2018. And the gap in the number of years that we can expect to live in good health between those in the richest and the poorest neighborhoods is 19 years current projections that unless there's a major change, that it will take almost 200 years to gain those extra five years in healthy life expectancy. On net zero, we've actually been making good progress, but in 2021, the Climate Change Committee expressed concern that the targets for 2035 will be missed, possibly by large margin, noting a lack of credible policies to reduce the greenhouse gas emissions, particularly from food systems and travel, including flying.
Chris - You've got to have targets to aim at though, haven't you? There's an old saying, isn't there? What gets measured gets done? So there's nothing wrong with having targets. Is your beef that the targets are off target to the extent that we are just not addressing them? Or is it that they're being set pie in the sky, that they're just so unachievable, unassailable that we may as well not have them?
Theresa - No, I think targets and timelines are really important. We achieve more with them and they're very ambitious. These targets. I think the problem is that the policies that have been implemented are not strong enough to achieve those targets. So as I say, they are ambitious, but if there were stronger policies in there that could achieve them, then the gap would be narrower. The other evidence that seems to be being neglected is the monitoring of these policies and when they're found to be off track, because there's uncertainty with all evidence and all policies. So you don't know until you've implemented about how well they're going to do. The important thing is to monitor and if you find that you are off track to then adjust the policy so that you can get back on track. And it seems that that adjustment is not happening, which is why these key ambitions are off track. Some to quite a large extent.
14:09 - New polio vaccine could eradicate it for good
New polio vaccine could eradicate it for good
Raul Andino, UCSF
Until the 1950s, polio killed and maimed millions. The discovery at that point, by Albert Sabin, of a weakened form of the virus that could be administered by mouth on a sugar lump was a game changer. And by the year 2000 the world was within a whisker of eradicating the disease. But there was a problem: in a small minority of cases, the weakened vaccine form of the virus would mutate and regain its virulence, seeding live polio virus back into the environment. Now scientists think they might have the answer: UCSF’s Raul Andino together with colleagues in the UK has produced a version of the polio vaccine into which they have engineered a number of additional genetic changes, further weakening the virus. Unless it reverts all 5 of these changes at the same time, which is a vanishingly remote possibility, it cannot become virulent again. Data from the World Health Organisation, who have tested these new vaccines, show they work, and suggest they give us our best chance yet of eradicating polio from its final strongholds on Earth…
Raul - In the 50s, there was two vaccines developed. One by Jonas Salk and one by Albert Sabin. Albert Sabin's vaccine was then used for many years to try to control polio myelitis. And the vaccine was very effective but not perfect because it was alive and sometimes could become more strong and could cause the disease itself.
Chris - But we have got killed polio vaccines that we're using in countries like the UK at the moment where we've eliminated the virus. It's not circulating in our country anymore. So we use the killed vaccine. So why can't we just use that everywhere around the world and solve this problem?
Raul - That's a good question. The killed vaccine is very effective to prevent disease, but it doesn't prevent the virus to circulate. It continues being transmitted from people to people in a silent form without causing disease. It's more expensive and you need medical personnel to administer the vaccine because it needs needles. In contrast, the Sabin vaccine, you give it orally and so you don't need a specialised personnel.
Chris - So your challenge then was to try to come up with something with all the virtues and benefits of that Sabin live vaccine that does endow sufficient protection to stop this virus circulating, but doesn't have the problem of the risk of it reverting back to being a transmissible, fully virulent virus capable of causing polio-like symptoms.
Raul - That's exactly right. So the key question here was can we modify the original Sabin vaccine without changing how effective it is and how easy it's to produce and to deliver, but prevent that Sabin vaccine now will acquire those mutations.
Chris - So how did you do that then? How did you change it in such a way that it would have those characteristics?
Raul - What we did is introduce and number of additional mutations in the genome to make the virus to have to go over many more mutations such as single one. The original Sabin vaccine with a single point mutation. You can make the virus as strong as the wild type and that virus could cause disease. And so what we did is introduce mutations that now all of them has to change at once. You need five mutations that needs to be reverted and so the probability for this to happen is much lower.
Chris - So the virus basically would have to change all five of those things all at once, all in the same virus to revert back. Whereas previously it would only have to change one. So the odds of that happening, you are arguing, are so slim that this makes what you've constructed much, much safer. But how did you know where to go? How did you pick on those places in the virus?
Raul - It was two particular things that we did. One is more trial and error and a particular region of the genome that we knew accumulated modifications that were causing the problem. And then the other one was a little bit more rational. We knew that there is a particular enzyme that makes the virus to introduce mutation and we modify that particular enzyme so it doesn't introduce those mutations and that reduced the ability of the virus to evolve.
Chris - And are you confident that having made these changes, you haven't affected the ability to grow the virus sufficiently so we can make vaccines from it? And secondly, when we put those viruses into people, they do the job as well as they did historically.
Raul - So what we did is first look at this in cell culture and in animal models in the lab, and it was very similar compared to the Sabin. Also in people with did clinical trials. And then people also demonstrate that what we call the kinetics of replication was very comparable to the original Sabin.
Chris - And you are confident that the people that have been challenged with this are now protected and will have the same duration of protection against polio for real, that they would've done had they had the original Sabin polio vaccine.
Raul - The World Health Organization, WHO, has used the new vaccine in about 28 countries and after 600 million doses later, we know the vaccine is safe and immunogenic and it has been effective to stop epidemics. So right now it's being used as an emergency measure. Moving forward, I think that is possible that with this vaccine, we replace the previous saving vaccine because it's safer.
20:37 - Euclid telescope prepares for launch
Euclid telescope prepares for launch
Guadalupe Cañas Herrera, European Space Agency
In just a few weeks, hopefully, a new European Space Agency telescope will be sent into space in a bid to explore the dark side of the cosmos. It is hoped that the Euclid mission will help shed new light on both dark energy and dark matter, which are two of the Universe’s biggest enigmas. The spacecraft’s telescope has two cameras: one to see visible light and the other to measure the distance between us and distant galaxies. Euclid will eventually settle at a point between Earth and the Sun which has one of the best views out into the cosmos.
Guadalupe - So there are two instruments that we have on board. One is a camera. So in that camera we will just take a picture where we will see galaxies in the sky. From that picture, we can actually obtain the position. So basically the altitude and the latitude the galaxy is placed in the sky. With the other instrument, we will measure the distance between us and that galaxy. And we already have three dimensions. With that, we can construct a map. The good thing about this map is that we can infer where that matter is located. We will do that not only by studying the position of the galaxies in the pictures, but also the shape of the galaxies. We know that the light that it is arriving from us, from really distant galaxies, that the form has deviated from due to the matter that is in the universe between those galaxies and us. By starting this cosmic history, we can study the evolution. So basically the speed at which the universe is expanding, that will help us to analyse dark energy. And then by inferring the distribution of matter overall in this map, we can actually extract some properties from that matter.
Chris - So if we look at really, really far away galaxies, the light we're seeing from those has been travelling for a long time. So we are seeing a long way back in the past when we look at those galaxies. When we look at nearer galaxies, that light's been travelling less far, so it's younger. So you can then see the effect of any influence on the growth of the universe in the meantime because it will be more manifest in the older ones than the younger ones. And that enables you to, I suppose, recapitulate what the universe has gone through as it's aged.
Guadalupe - Exactly. That is exactly the point.
Chris - We think the universe is about 13.8 billion years old. We know it grew really fast when it was first born at the big bang, then it slowed down a bit and now we think it's speeding up again. When in the timeline, between 13.8 billion years ago and now, are you looking and why do you think that we are seeing this acceleration of the universe the way that we are?
Guadalupe - So we are looking between now and 10 billion years in the past, and this is exactly the time range in which we believe that dark energy has started dominating and therefore the universe started accelerating its expansion. This is the moment that we are really interested in looking at because the structure that we see in our universe has already formed. So galaxies had already formed, clusters of galaxies had already formed, and we can actually study the distribution of this matter in the universe, which is the main measurement that we want to achieve with Euclid.
Chris - Was there no dark energy around before about 10 billion years ago then, or was there just not as much of it and that's why the trajectory changed at that point?
Guadalupe - So dark energy is really puzzling. Even though we believe that at the beginning of the universe still 70% of it was dark energy, that ingredient, despite being dominant, wasn't the one that had the largest influence in the expansion of the universe and on how it was evolving in time. However, right now is when it has started dominating the ratio of expansion. And this is why our model does not only need to explain why our universe is accelerating its expansion right now, but also why, at the beginning, other ingredients such as our ordinary matter, or matter in general, played a more significant role in the past.
Chris - It's really interesting that you say that because previously many physicists have said, the more universe we get, the more it grows, the more dark energy we get and that's why things are speeding up. But you've made a subtle point, which is saying the dark energy hasn't changed, but it's how it behaves, or how the universe responds to that dark energy, that has changed and that is accelerating. The response, the sensitivity to the amount of dark energy is increasing, so it's having or wielding more of an influence now than it did.
Guadalupe - Exactly. So this is why this relation to how much the universe was growing and how much the universe's space was being created had some influence in the expansion of the universe. It's because we thought, "okay, we don't know what dark energy is, but at the beginning of the universe, space time was definitely smaller and now it's getting bigger and it is getting bigger in an accelerated way. So what are we having now that we didn't have before" More empty space. And this is why we try to postulate that this dark energy is somehow associated with the energy of emptier space. And this is why we are starting to see how its role is more dominant now just by simply thinking, "okay, now there is more empty space." However, it's really tricky to keep this theory on hold because you need to actually make a relation between vacuum energy and also the quantum world. So you need to come back to quantum physics and if you actually make some predictions of how important the energy of the vacuum can actually be from the quantum physics point of view, it is not enough to explain what we are seeing right now at our universities. This is why it is one of the biggest mysteries that we have right now in more than cosmology.
Chris - So when will Euclid take to the skies and when will you begin to see first light? When are you going to first begin to get data flowing back from the instruments?
Guadalupe -So the project will be six years, and this is actually all the time that we need to take pictures of this one third of the sky. So Euclid won't have holidays. There will be a possibility of having four years extension to this mission, but we will need to decide on the scientific goals after that. But, in principle, we're going to be busy for six years.
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