Antimatter Achievement: Scientists Successfully Trap Positrons for Months

[00:00:00] [SPEAKER_03] This is Space Time, Series 29, Episode 128, full broadcast on the 26th of October, 2026. Coming up on Space Time, scientists trap antimatter, successfully holding it for months, liftoff for Japan's sample return mission to the red planet Mars, and the time lords have demanded a change in how science understands time. All that and more coming up on Space Time.

[00:00:28] [SPEAKER_02] Welcome to Space Time with Stuart Gary.

[00:00:48] [SPEAKER_03] Physicists have successfully trapped an antimatter particle called a positron in an experiment that helped set the stage for one of the toughest tests yet for the standard model of particle physics, the foundation stone of science's understanding of the universe. The new study, reported in the journal Physical Review Letters, could eventually enable the most precise test yet of a fundamental symmetry between electrons and their antimatter counterparts.

[00:01:14] [SPEAKER_03] See, the problem is, equal amounts of matter and antimatter were created in the Big Bang 13.8 billion years ago. However, as matter and antimatter annihilate each other when they come into contact, the universe should have disappeared in a flash of gamma ray light almost immediately after it formed. Yet, clearly that didn't happen, and we live in a universe dominated by what we call matter, rather than antimatter.

[00:01:39] [SPEAKER_03] The positron is the positively charged antimatter counterpart to the negatively charged electron. According to the standard model, electrons and positrons should be perfect mirror images of each other. So, by measuring the positron's magnetic properties with unprecedented precision, and then comparing those with the electrons' properties, physicists should be able to put this fundamental symmetry to its most stringent test yet. And if the measurements don't match up as expected,

[00:02:06] [SPEAKER_03] that would reveal a crack in the standard model of particle physics, offering new clues to enduring mysteries, including why ordinary matter, rather than antimatter, dominates the universe. After first capturing the fast-moving particle from radioactive decay, the authors cooled it to nearly absolute zero. They then suspended the particle in a near-perfect vacuum, preventing it from touching ordinary matter, an encounter which would cause it to annihilate. By trapping and cooling a positron in this way,

[00:02:35] [SPEAKER_03] the authors created what they're calling a one-positron quantum cyclotron. In this state, the positron essentially behaves very much like an artificial atom. With quantum energy levels, scientists can precisely control and observe. The study's lead author, Gerald Gabriels from Northwestern University, says if you take an electron and a positron and collide them together, they'll both disappear. They'll annihilate each other. And he says the big mystery of the universe is the fact that the Big Bang

[00:03:02] [SPEAKER_03] should have created equal amounts of matter and antimatter. But if that were true, it would annihilate, and we'd be left with nothing. So clearly there's something wrong with the theory, and that's what science is trying to figure out. The standard model of particle physics is a long-standing hypothesis, describing the fundamental particles and three of the four fundamental forces, the electromagnetic force, the strong nuclear force, and the weak nuclear force. Experiment after experiment has confirmed the model's predictions with extraordinary precision.

[00:03:32] [SPEAKER_03] Yet physicists know the model's not complete. It doesn't explain dark energy or dark matter. Nor can it explain why the observable universe contains overwhelmingly more matter than antimatter. Gabriel says science knows the standard model has to be wrong somewhere, or at least incomplete. Nearly everything on Earth is made of just three familiar particles, electrons, protons, neutrons.

[00:03:57] [SPEAKER_03] And an antimatter universe instead could be built from the antimatter counterparts, positrons, antiprotons, and antineutrons. Gabriel says the simple fact is if everything on Earth were antimatter, it would be difficult to tell the difference. The fireworks only occur when the two worlds, matter and antimatter, meet. Now one of the problems with testing all this is that scientists can't simply put a positron into a conventional container.

[00:04:23] [SPEAKER_03] That's because touching the container itself, which is normal matter, would cause the antimatter particle to annihilate. So if scientists want to study antimatter, they need to handle it really carefully. So, to carefully handle the particle, the authors used a state-of-the-art trap, which combines specialised electric and magnetic fields in order to suspend the positron in a void. Sitting in the middle of this container, the positron never touches anything.

[00:04:48] [SPEAKER_03] And because of this set-up, the positron in Gabriel's laboratory has remained trapped for months. Mind you, catching the positron in the first place was its own challenge. Positrons can be generated during radioactive decay of certain atomic nuclei. And in this experiment, Gabriel's used nuclei from sodium-22, a rare radioactive isotope of sodium. When the particles emerge from the nuclei, they carry enormous amounts of energy.

[00:05:14] [SPEAKER_03] So the team first needed to slow down the positron, and then guide it into the trap's near-perfect vacuum. The interior of the trap is cooled to just 0.3 degrees above absolute zero, which is minus 273.15 degrees Celsius. Gabriel's and colleagues also demonstrated that they could precisely manipulate and detect the positron's individual quantum energy states.

[00:05:37] [SPEAKER_03] By delivering carefully tuned microwaves, they added tiny precise amounts of energy to the positron and detected its resulting quantum transitions. And that level of control is essential for scientists' ultimate goal, measuring the positron's magnetic properties with extraordinary precision, and then comparing them with those of an electron. Now in previous work, Gabriel's used a one-electron quantum cyclotron to measure the electron's magnetic moment to about one part in 10 trillion,

[00:06:06] [SPEAKER_03] which is among the most precise measurements ever made for any elementary particle. Now with the trapped antimatter, Gabriel's plans to make the same kind of quantum measurement with the positron, and then put the two results head-to-head. He says current theory suggests there should be no difference between the two measurements. But if it turns out they're not equal, that would be the biggest discovery in physics in the last century. And needless to say, we'll keep you informed.

[00:06:35] [SPEAKER_03] This is space-time. Still to come. Lift off for Japan's first sample return mission to the red planet Mars. And the time lords have demanded a change in how science understands time. All that and more still to come on space-time.

[00:07:05] [SPEAKER_03] Japan's Martian moons exploration MMX mission is now on its way to the red planet's moon Phobos, following a successful launch from the Tanegashima Space Center, 1,000 km south of Tokyo.

[00:07:17] [SPEAKER_00] Airplane system, have-set準備完了.

[00:07:19] [SPEAKER_03] All systems go.

[00:07:20] [SPEAKER_00] Engine start. My engine start. Zero. It's RG3, turn on, lift off. We have a successful lift-over, H2 launch peak of number 10, with an MMM spacecraft on board from Jakusa Tanagashima Space Center.

[00:07:34] [SPEAKER_03] The 4.5-ton spacecraft will arrive at Mars in August next year, spending several years orbiting the 27-kilometre-wide potato-shaped moon, undertaking readings and searching for appropriate landing sites. In 2029, it'll deploy a small 25-kilogram four-wheeled land rover called IDFX, which will descend down to the Phobos surface and undertake preliminary observations, before MMX itself drops down to the surface,

[00:08:00] [SPEAKER_03] undertaking several touchdowns in 2030, collecting up to 10 grams of samples. These will then be loaded onto a return module, which will fly back to Earth in 2031, parachuting down into the Woomera rocket range in outback South Australia for collection by scientists. Dr Sarah Webb from Swinburne University says those samples will help answer key questions about the origins of both Martian moons, Phobos and Deimos.

[00:08:26] [SPEAKER_03] They're either captured asteroids from the nearby main asteroid belt between Mars and Jupiter, or they're the remains of a debris ejector thrown out into orbit following a giant asteroid impact onto the Martian surface.

[00:08:39] [SPEAKER_01] So this mission called Martian Moons Exploration, or MMX for short, is quite exciting. It's led by the Japanese Space Agency, and its whole goal is not only to go to Mars to orbit around Phobos, but you actually collect a sample of it and return it back to Earth. And if successful, this will be the first time ever that a sample has been collected from the Martian planet system and then brought back to Earth for further analysis. So us, our scientists are shaking in our boots, getting really excited,

[00:09:06] [SPEAKER_01] because this is things that we've been waiting for for decades, and it's now within reach.

[00:09:09] [SPEAKER_03] Critics are going to say it's Phobos, it's not Mars. The Moon was chosen because it's easier to land there, it's easier to take off from it.

[00:09:17] [SPEAKER_01] That's right, much easier. And we don't know what Phobos is, as well. We theorise that it's likely a captured asteroid, but there's also a theory that it is the left of a chunk of Mars that formed because of a giant impact. And so we really don't actually know until we get our hands on that material and be able to analyse it in more detail.

[00:09:33] [SPEAKER_03] That's one of the first things you learn in astronomy school. Is Phobos a chunk of Mars that's been blasted into orbit, or is it a captured asteroid?

[00:09:40] [SPEAKER_01] That's right. It's a mystery that hopefully by 2035, once we have the sample graph on Earth, we might be able to answer. And then that has a lot of rundown consequences for what we understand about our solar system as well, because Mars is the only other rocky planet aside from Earth that has moons. But its moons are obviously very different to our own gigantic, very influential moon that we have here on Earth.

[00:10:03] [SPEAKER_03] Yeah, we got our moon thanks to the giant impact. We did. Mars, on the other hand, is the only place in the universe that we know of, other than Earth, where there's a real likelihood, a real potential for life to have existed there. It was once warm and wet, and as it cooled, it lost its protective shielding, its atmosphere, and the water that was there slowly evaporated and degassed into space. Any life now would be fossilised, and there are tantalising signs of that in places like Chiava Falls.

[00:10:31] [SPEAKER_01] I think it is exceptionally exciting. As you said, Mars is on a very different planet, very similar to Earth in a lot of ways. And if life did exist there, those fossils should remain in the fossil record. And so I think that's one of the biggest questions we have just in general as humans, as beings, is are we alone in the universe? Is life only on the Earth, or are we going to find it elsewhere? And the first place to really dig into that is our own solar system. We've got some tantalising candidates.

[00:10:58] [SPEAKER_01] We know that we've got moons around Jupiter and Saturn that likely have big subsurface oceans that could have life in them, but they're very far away. They're less tangible to us to physically think about going and collecting samples to analyse, whereas Mars is right there. Yes, it's far away, but it's fairly close to the Earth. We can get there within a year or two. We can collect a sample and bring it back in less than a decade. So it is that kind of holy grail of can we answer this question with one simple sample?

[00:11:24] [SPEAKER_03] And it's easier to launch off because it's so much smaller.

[00:11:27] [SPEAKER_01] It is, that's right. Gravity is relentless, unfortunately, in the universe. All things fall at the whim of gravity. And so if you have a smaller mass, a smaller planet or a small moon, how wonderful you're able to get that exit velocity you need to get on your merry way. Whereas launching things from Earth is very doable. We've done it for decades now, but it is extraordinarily expensive to fight against that force of gravity and get things into orbit and away from the Earth as we need to.

[00:11:53] [SPEAKER_03] China are likely to undertake their sample return mission to Mars and return those samples possibly by 2029. That's very exciting. The American-European mission, which was the final stage of what the Mars Perseverance rover is doing on Jezero crater now, that's sort of up in the air at the moment, no pun intended, because of federal funding. But nevertheless, it's got the samples. They're lying there on the surface to be collected. They are. We just have to go back there and get them.

[00:12:22] [SPEAKER_03] It's a very interesting stage in research right now. It must be really frustrating as a scientist involved in this type of research to see one of your goals so near and yet out of reach.

[00:12:34] [SPEAKER_01] So far, I think it is a very unique time in history where we know so much and so little and we know what we need to do to be able to advance our knowledge. And yet we're constantly blocked by challenges, by different challenges that are global at this point. But certainly when we're looking to the United States, that has been a large halt on what we thought the direction of science is going to be in the next 10, 20 years.

[00:12:59] [SPEAKER_01] And so as a scientist worldwide, we've got this collective worry of we know what we need to do for advancing human knowledge, not just in astronomy or space exploration, but in medicine and things that are really going to change our lives. And yet we're halted by funding.

[00:13:14] [SPEAKER_01] And I think this is a universal problem and something that here in Australia, a lot of scientists have been quite vocal about with our Academy of Science, trying to advocate to all of the MPs around our country how vital scientific research is for our everyday lives and how it should be funded significantly. Because we only know that good consequences will come when we put in that money.

[00:13:34] [SPEAKER_03] Yeah, the loss of funding for the European Southern Observatory project that is such a massive blow. That is devastating.

[00:13:42] [SPEAKER_01] It is devastating. And Australia has this phenomenal history, especially in astronomy, where we've got that way above our weight in terms of a global scale. And with the European Southern Observatory, it was not only for the astrophysics and the observations of it all, it was actually for the instrumentation as well, which Australia is a world leader at. And so the community right now, and speaking from coming from that astronomical community, is trying to figure out, well, what is next for us?

[00:14:09] [SPEAKER_01] Where can we maybe have different access to different telescopes to help support the goals to keep Australia on top? And all those trickle-down technologies that come from it, all the instrumentation that ends up going into other sectors, all those algorithms and those skills for people that we train that end up going into other sectors, all within the Australian economy. So it is a very interesting challenge and one that we were keen to solve.

[00:14:34] [SPEAKER_03] I keep thinking of the LIGO experience that we had a few years ago where LIGO offered Australia a gravitational wave detector. It was there. It was waiting. The plans were there. And the Australian government said no. So it went to India and India still haven't built it, unfortunately.

[00:14:52] [SPEAKER_01] Yes, it is difficult. I think what's so challenging is in a funding-limited environment where you've got more people fighting to do good work and all work in the scientific community across Australia is good and worthy work. And it's very difficult. You can't, it's very, very difficult to say this is more deserving of this or this or that. And it is an extremely difficult landscape.

[00:15:13] [SPEAKER_01] And I think one way to solve that is to have a landscape that has more funding with bigger dedicated visions for specific funding for specific goals that is able to help serve those communities.

[00:15:24] [SPEAKER_03] That's Dr. Sarah Webb from Swinburne University. And this is Space Time. Still to come, the Time Lords demanded change in how we understand time itself. And later in the Science Report, a world first Australian-developed personalised mRNA melanoma vaccine. All that and more still to come on Space Time.

[00:16:01] [SPEAKER_03] Scientists are changing the way we measure time following a decision to abolish the leap second. Leap seconds are added or deducted every few years in order to keep the world's atomic clocks aligned with the actual rotation of our planet. So that seasons start where they're supposed to. Computers perform as they should and satellite navigation systems work correctly.

[00:16:22] [SPEAKER_03] The world's clocks are governed by their seconds, 60 of them in every minute, 3600 in every hour and 86400 in a standard mean solar day. By the way, a standard mean solar day is the time it takes the Earth to complete one full rotation, placing any given spot with the Sun at zenith, that is directly overhead, directly back at zenith, one full planetary rotation later.

[00:16:47] [SPEAKER_03] That's very different to a sidereal day, which is used by astronomers and observatories to track the Earth's rotation as referenced by a bunch of fixed, seemingly unmoving background stars. The sidereal day shows that the Earth's day is actually just a little bit shorter, 23 hours 56 minutes and 4 seconds. That's 86,164.09 seconds of mean solar time. That difference happens because as the Earth spins on its axis, it's also moving along its orbital path around the Sun.

[00:17:17] [SPEAKER_03] So to bring the Sun back to the exact same overhead position, the Earth needs to rotate not 360 degrees, but actually 361 degrees. That takes an extra 4 minutes, hence the time difference. Measuring the exact time on Earth nowadays is achieved by a global system of atomic clocks, collectively known as Coordinated Universal Time or UTC, Zulu if you're in the military. It's the gold standard. It never changes for daylight saving or for regional differences.

[00:17:47] [SPEAKER_03] So 1200 UTC in London is the same as 1200 UTC in Sydney or in Turkey or Washington or even aboard the International Space Station. Originally, every town and village kept its own local time. Basically, 12 noon was when the Sun was directly overhead in your local village. But the arrival of the railways in the 1800s forced countries to introduce standard time zones so trains wouldn't crash into each other.

[00:18:12] [SPEAKER_03] And with the arrival of standard time zones across the globe, navigation became easier and businesses flowed more smoothly. It was a great idea. But with the arrival of the computer age in space flight, accuracy has become of prime importance. You see, precision counts. The Earth's rotation tends to wobble and gradually slow down. It's due to tidal friction and geological events like earthquakes.

[00:18:36] [SPEAKER_03] It makes the planet's rotation an unreliable standard for modern science, navigation and internet systems. So as clocks needed to become more and more accurate, scientists moved away from traditional mechanical and electrical devices and began relying ever more on advanced atomic clocks. In 1967, the governing body of the International Bureau of Weights and Measures, which standardizes the Ward's measurements, adopted a more precise definition of a second based on the measurements of cesium atoms.

[00:19:05] [SPEAKER_03] And this is what underpins coordinated universal time. Atomic clocks use cesium fountains to track time with extreme accuracy. Cesium gases cool down to near absolute zero, minus 273 degrees Celsius, and then pushed up as a fountain through a microwave filled cavity. The microwaves are adjusted until they match the exact natural resonance frequency of the cesium atoms, allowing the clock to count the fixed number of cycles that define a second.

[00:19:32] [SPEAKER_03] This method is so exact that cesium clocks neither gain nor lose a single second in tens of millions of years. And this level of precision has allowed the second to be measured by counting 9,192,631,770 oscillations, or radiation cycles, of a cesium-133 atom during its unperturbed ground state hyperdefined transition. But the precision of atomic clocks have their own problems,

[00:20:00] [SPEAKER_03] because they pick up changes in the variability of the Earth's rate of rotation. And that's where leap seconds come in. Since their introduction in 1972, leap seconds have been added to our clocks on 27 occasions, most recently at the end of New Year's Eve 2016. The additional leap seconds keep atomic clocks accurate, navigation systems precise, moving transport smoothly, or at least trying to, and coordinating everything from big business transactions to the automated docking of spacecraft in orbit,

[00:20:30] [SPEAKER_03] even when the power output needs to be increased during ad breaks in televised football games. These changes, by adding leap seconds, compensates for the known variabilities in the rotational speed of the planet's axis. Without them, time would slowly drift away, out of coordination, and into ever-increasing confusion. But the real need for leap seconds came when scientists determined that the Earth's axial rotation rate simply wasn't consistent enough.

[00:20:58] [SPEAKER_03] See, the Earth's axial rotation changes due to things like mass redistribution and torque forces acting on the planet. While we think of the Earth as a rigid cue ball, it's actually a very dynamic, slightly squashed sphere with a molten core, fluid oceans, a shifting atmosphere, and moving tectonic plates. Any event that shifts mass closer or further from the Earth's rotational axis changes the planet's axial spin. That's due to the conservation of angular momentum,

[00:21:24] [SPEAKER_03] much like a spinning figure skater pulls their arms in to spin faster. Overall, there's a long-term slowdown of the planet's spin rate over centuries and millennia. That's caused by gravitational tidal friction with the Moon, and to a lesser extent the Sun. See, the Moon's gravity pulls on the Earth's oceans, creating tidal bulges. And because Earth rotates faster than the Moon orbits it, the Earth tries to drag its watery bulge ahead of the Moon.

[00:21:50] [SPEAKER_03] This causes the Moon's gravity to act like a sort of brake pulling back on this bulge, steadily draining the Earth's rotational energy, which causes the Earth's day to lengthen by about 2.3 milliseconds every century. And it doesn't end there. There are other factors influencing the Earth's axial spin as well, including the climate and the last ice age, which physically covered the planet in a thick, heavy shed of ice, altering the shape of the Earth. Post-glacial rebound following the melting of those billions of tons of ice cover

[00:22:19] [SPEAKER_03] has slowly seen the distribution of mass shift relative to the planet's centre of gravity. During the last ice age, heavy glaciers flattened the Earth's poles. Now that most of that ice has melted, the land at the poles is slowly bouncing back upwards, making the planet more spherical. And this is shifting mass closer to the axis, speeding up the planet's rotation. There are also modern changes, such as the rapid melting of glaciers in Greenland and Antarctica,

[00:22:46] [SPEAKER_03] which is dumping water back into the oceans, redistributing mass towards the equator. Again, acting like that figure skater, extending their arms to slow down rotation. The Earth's spin also changes dynamically from day to day and season to season, because of the weather, with wind patterns and strong global wind systems like jet streams pushing hard against the Earth's surface topography, like mountain ranges. When strong winds blow in the direction of the Earth's rotation,

[00:23:11] [SPEAKER_03] the atmosphere gains angular momentum, causing the solid Earth to slow down slightly to compensate. And this causes seasonal variations of up to a millisecond per day. And internal planetary mechanics also play an important role. Forces deep within the planet and sudden tectonic movements such as earthquakes cause unpredictable changes deep inside the Earth. A primary cause is the drag along the core-mantel boundary layer. The Earth's molten iron outer core sloshes around independently

[00:23:40] [SPEAKER_03] of the base of the rocky mantle layer above it. Changes in magnetic fields and fluid currents at the core-mantel boundary can also cause the crust to speed up or slow down over decades. And then there are mega earthquakes, like the 2004 Indian Ocean tsunami or the 2011 Japanese earthquake, which instantly shift billions of tons of mass enough to permanently speed up rotation, shortening the day by about 1.8 microseconds. And all these events are making timekeeping in the space age increasingly less and less accurate.

[00:24:09] [SPEAKER_03] And so in 1972 scientists introduced the leap second, a one-second adjustment added to coordinated universal time to keep highly precise atomic clocks synchronized to the Earth's natural irregular rotation. Because the planet's rotation fluctuates and gradually slows down over long periods, a discrepancy slowly builds between astronomical time and atomic time.

[00:24:33] [SPEAKER_03] And when the gap approaches 0.9 seconds, a leap second is inserted, making the final minute of that day 61 seconds long, counted as 23, 59 and 60 seconds, usually on New Year's Eve. But while leap seconds keep clocks aligned with space, they're an operational nightmare for modern-day digital infrastructure, causing systems to regularly crash and giving computer-programmed software writers, still recovering from the Y2K bug, conniptions.

[00:24:59] [SPEAKER_03] And the next big leap second insertion will be a negative event, removing a second from the clock. The need for a negative leap second is due to changes in the Earth's core, which has actually caused the planet to temporarily speed up. And this raised fears that scientists would have to implement a negative leap second, a 59-second minute. And that's going to send software engineers into uncontrollable nervous breakdowns. Few will survive without their teddy bears.

[00:25:25] [SPEAKER_03] Now, global tech companies have warned that software infrastructure is entirely untested for deleting a second. That's created a massive risk of severe widespread digital breakdowns. Again, think Y2K. So to eliminate these risks, delegates from 69 countries at the International Bureau of Weights and Measures, meeting back in 2022, voted to remove leap seconds by 2035 and start discussing a different method of keeping the Earth's days in sync with the astronomical world.

[00:25:54] [SPEAKER_03] But the urgent need to introduce a negative leap second has forced the group to vote again last week, this time to bring the abolishment of the leap second forward to 20 May 2027. Under the new rules, rather than micromanaging a one-second gap, the allowed drift between atomic time and the Earth's rotation will be expanded to a full hour. Clocks will continuously run without interruption. Over centuries, our time will slowly drift out of alignment with the Sun.

[00:26:22] [SPEAKER_03] And eventually, like in thousands of years from now, future generations will simply implement a single leap hour, treating it much like a predictable daylight savings time shift. This is space time.

[00:26:49] [SPEAKER_03] And time now to take a brief look at some of the other stories making use in science this week, with a science report. Scientists have announced a major breakthrough in skin cancer treatment with the world first Australian-developed personalized mRNA melanoma vaccine. Clinical trials of over 1,100 patients showed that adding antismorant to the standard post-surgery treatment reduced the risk of melanoma returning within two years by at least 42%.

[00:27:15] [SPEAKER_03] 82% of people in the trial's vaccine group were still living without a recurrence of their cancer after two years, compared to 70% on the standard Keytruda treatment alone. The trial is continuing in order to track longer-term outcomes. A new study has shown a catastrophic collapse of environment and marine life in the wake of the 2010 BP Deepwater Horizon oil spill. The findings, reported in the Proceedings of the National Academy of Sciences, PNAS,

[00:27:44] [SPEAKER_03] found that populations of deepwater fishes, crustaceans and squid declined significantly over the past 16 years since the BP ecological disaster first unfolded. The study included over 2,000 net samples, acoustic surveys and genetic analyses. It revealed declines in 64% of fish numbers, 62% of large crustaceans and 60% in small squid and other cephalopods. And some of the most ecologically important animals were hit even harder.

[00:28:14] [SPEAKER_03] Krill declined by 83%, lantern fishes by 63% and Bristol mouth fishes by 69%. These concentrations are essential for whales, dolphins, tuna, sharks, seabirds and other marine life. Aquatic life that was common back in 2011 has now virtually disappeared. BP's Deepwater Horizon oil spill released between 4 and 4.9 million barrels of oil, while approximately 770,000 gallons of chemical dispersant were injected near the wellhead.

[00:28:43] [SPEAKER_03] All related compounds have since been detected in deepwater fish eggs and encephalopod tissues. It's an environmental disaster on an unprecedented scale. Breakdown plastics such as polyurethane in shoe foam, kitchen sponges and mattresses can be a problem for recycling. Now, scientists have improved an enzyme normally produced by bacteria found in compost to enable it to more efficiently break down polyurethane products.

[00:29:10] [SPEAKER_03] Researchers edited the DNA of the bacteria to produce a more efficient version of a plastic eating enzyme. They tested the enzyme on pieces of soles of shoes, and after three days, it had chewed up about 1.4% of the polyurethane, splitting the waste product into smaller reusable pieces. A report in the journal Chem Catalyst claims that, although their research is still in its early stages, it does show promise for future plastic reprocessing.

[00:29:37] [SPEAKER_03] A new study has found that people who spend more time with their pet cats tend to have more positive moods. The findings, reported in the journal iScience, are based on a trial involving 29 cats and their human companions. The authors conducted hormonal analysis through urine samples, attached small Bluetooth low-energy beacons to the cat's collars to measure their physical daily proximity, assessed the owner's mood through questionnaires, and observed the cat's behavior towards their owners and towards unfamiliar people.

[00:30:07] [SPEAKER_03] The findings revealed a hormonal connection between cats and their humans involving oxytocin and cortisol, hormones that are associated with social relationships and stress. They showed a positive correlation in concentrations of oxytocin for both the cats and their people, with higher oxytocin levels in cats linked to lower cortisol levels and fewer negative feelings in their owners. Ultimately, the authors observed that positive mood states in the owners were not connected to how long they've had their cats,

[00:30:34] [SPEAKER_03] but rather to the overall physical proximity between owners and their pets. In other words, owners' positive feelings seem to be most strongly associated with how much time they spend with their cats in everyday life. A new documentary has been released exposing the famous Patterson-Gimlin Bigfoot film as a fake. The iconic shaky 59-second silent 16mm clip shows what appears to be an enormous female Sasquatch walking along a trail at Bluff Creek, California.

[00:31:05] [SPEAKER_03] Skeptics have long claimed it's just some dude in a gorilla costume. And in 2002, Philip Morris, who runs a North Carolina-based company offering costumes, props and stage products, claimed that he made the gorilla costume that was used in the film, but had been reluctant to expose the hoax earlier for fear of harming his business. Meanwhile, a few years earlier in 1999, long-time Patterson and Gimlin friend Bob Heronius admitted that he was the figure wearing the costume in the film.

[00:31:30] [SPEAKER_03] He says he had not gone public earlier because he was afraid of being convicted of fraud for his part in the hoax, but agreed to finally go public following legal advice. The Skeptics' Tim Mendon says the new film, Capturing Bigfoot, which exposes the hoax, has just been released on cable.

[00:31:46] [SPEAKER_02] The footage is probably one of the most famous film videos of a cryptid, an unknown creature, especially a legendary one. And this is the one taken in 67 in a place called Bluff Creek in California by two, I don't know, actually what they were actually, adventurous documentary makers, who knows, happened to have a 16mm camera with them. And they filmed a Bigfoot, a Sasquatch, a tall creature, hairy creature, walking along near a creek, sort of a stony tree background. It walks along, it looks at them, sort of strolling, it's not exactly running anywhere, and then walks on and disappears.

[00:32:16] [SPEAKER_02] And the film runs for about almost a minute and became sort of proof for a lot of people that Bigfoot exists. Now, people have always been investigating it, you get Hollywood makeup people trying to see if the costume is real, there is a costume, and the suggestion always has been that it's a fake footage. It's quite reasonable, it's probably one of the clearest bits of footage of such a creature, and it goes for a long time. So it's not a fleeting thing disappearing behind a tree. But, since then, a filmmaker has made this documentary recently that's appeared, Mark Evans, called Capturing Bigfoot.

[00:32:46] [SPEAKER_02] And it contains a 40-second clip from a year earlier, from 1966, of Bigfoot walking, being filmed in much the same way, which they're saying is a trial run for the later 1967 famous clip. They've also spoken with a gentleman who said he was actually inside the costume, which is a lot older now, and that he explained what happened after how it was set up. And a son or a grandson or something like that of the, one of the Patterson or Gimlin,

[00:33:12] [SPEAKER_02] one of the two guys who made the film, witnessing their relative burning the costume in the backyard. So, it's a, it was always a controversial film. It was quite a nice film to look at. It probably convinced a lot of people. But there's been a lot of problems with it. Everything from how the animal moves, the shape of the animal, does it have breasts? Does it not have breasts? Male, female, et cetera. The way it sort of just saunters across the landscape, gives a look to the researchers. Very unlike most Sasquatch stories you've ever heard. And trying to get a better grip on it.

[00:33:38] [SPEAKER_02] So, this film contains probably evidence which is as definitive as the original Patterson-Gimlin film. So, you think, oh, all right, okay, which one is real? So now there's some firmer quotes, evident, in quotes, that the original film is not true. Not that anyone who seriously investigates Christians really does think it's true. But I'm sure there are people who still do. Probably the people involved, Patterson. Patterson died not long after in 72. It's interesting that this new evidence has cropped up.

[00:34:05] [SPEAKER_02] Pretty much saying we have the silver bullet that proves that the original film is not true. What a shame. Really. It'd be nice if it was true.

[00:34:12] [SPEAKER_03] We all want Bigfoot to be real, but yeah.

[00:34:15] [SPEAKER_02] But you've got to have the evidence.

[00:34:16] [SPEAKER_03] You need a corpse or the DNA evidence at least.

[00:34:20] [SPEAKER_02] Well, they're also saying, of course, you need about a hundred big feet. Well, you need several hundred Bigfoots. It's not Bigfoot.

[00:34:27] [SPEAKER_03] In order to have a viable breeding population, yeah.

[00:34:30] [SPEAKER_02] That's right. And that's a lot of Bigfoots.

[00:34:32] [SPEAKER_03] Not to be recorded by people who have cameras on their cell phones.

[00:34:35] [SPEAKER_02] That's exactly right. Everyone carries a camera now. You don't need a 16mm camera. Everyone's got a camera in their pocket. And it's pretty good quality, but no one has really come up with definitive films. It's amazing how often people see Bigfoot. Some of them for a lengthy period of time, they forget to film it. And there's no, every Bigfoot makes you most see these days as fuzzy. Perhaps Bigfoot's fuzzy. Squatch blobs.

[00:34:55] [SPEAKER_03] They're called Squatch Blobs.

[00:34:57] [SPEAKER_02] And, I don't know, it's a fascinating area for as much for the psychology of belief as it is for any actual evidence of a humanoid. People want to believe. People do. Yeah, that's okay. People want to believe. It doesn't mean it's true.

[00:35:12] [SPEAKER_03] That's the skeptics Tim Mendham. And this is Space Time. And that's the show for now. Space Time is available every Monday, Wednesday and Friday through Bytes.com, SoundCloud, YouTube,

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