S27E58: Earth's Fading Shield: The Magnetic Trigger for Life's Diversity

[00:00:00] This is SpaceTime Series 27 Episode 58 for broadcast on the 13th of May 2024.

[00:00:07] Coming up on SpaceTime.

[00:00:09] How a weak magnetic field may have supported the diversification of life on Earth.

[00:00:15] New observations showing the power of black holes is even greater than previously estimated.

[00:00:21] And the launch of China's Changi-6 lunar sample return mission.

[00:00:26] All that and more coming up on SpaceTime.

[00:00:30] Welcome to SpaceTime with Stuart Gary.

[00:00:49] A new study has found that an unusual reduction in the strength of Earth's magnetic field

[00:00:54] may have triggered the diversification of life on Earth.

[00:00:58] The findings reported in the journal Communications, Earth and Environment show

[00:01:02] that between 591 and 565 million years ago the Earth's magnetic field weakened.

[00:01:08] And that just happens to coincide with a significant increase in oxygen levels

[00:01:13] in the planet's atmosphere and oceans.

[00:01:15] The study's authors including John Taduna from the University of Rochester hypothesized

[00:01:20] that this increase in oxygen levels supported a sudden diversification of life forms

[00:01:25] resulting in the evolution of some of the planet's earliest complex organisms.

[00:01:30] Between 600 million and 540 million years ago,

[00:01:34] life on Earth consisted of soft-bodied organisms known as Idiacra and Fauna,

[00:01:39] the earliest known complex multicellular life.

[00:01:42] The fossil record shows that these organisms significantly diversified in complexity and type

[00:01:47] between around 575 and 565 million years ago.

[00:01:52] Our previous research had already suggested that this diversification was linked to a

[00:01:57] significant increase in atmospheric and oceanic oxygen levels that occurred

[00:02:01] roughly the same time period.

[00:02:03] The problem is no one's been able to work out exactly why the oxygen level suddenly changed.

[00:02:09] Scientists analyzed the magnetic properties of 21 Pledge-O-Clase crystals,

[00:02:14] a common mineral in Earth's crust which were extracted from a 291 million year old rock formation

[00:02:19] in Brazil. Pledge-O-Clase crystals contain tiny magnetic minerals.

[00:02:25] These preserved the intensity of the Earth's magnetic field at the time they were formed.

[00:02:30] Analysis of the crystals showed that at their point of formation,

[00:02:33] the Earth's magnetic field was at the weakest ever recorded.

[00:02:37] In fact, it was some 30 times weaker than both the current magnetic field intensity of the Earth

[00:02:41] and also that measured in similar crystals formed approximately 2 billion years ago.

[00:02:46] The authors combined their results with previous measurements to establish that the Earth's

[00:02:51] magnetic field was at a weak level for approximately 26 million years from roughly 291

[00:02:57] million years ago to 265 million years ago.

[00:03:01] And this overlaps with the rise in oxygen which occurred between 275 and 265 million years ago.

[00:03:08] So, how did the two work together?

[00:03:11] Well, the authors proposed that the weakened magnetic field may have allowed more hydrogen to

[00:03:16] escape into space. That would have resulted in a greater percentage of octogen atoms being in

[00:03:22] the Earth's atmosphere and oceans. And that in turn supported greater diversification of

[00:03:27] types and complexity of living organisms. And of course, that eventually led to humans.

[00:03:33] This space time. Still to come. A new study shows how quickly erupting supermassive black

[00:03:40] holes can shut off star formation in galaxies. And China successfully launches its Changi-6

[00:03:46] sample return mission which will attempt to collect the first lunar rocks from the

[00:03:50] far side of the moon. All that and more still to come on space time.

[00:04:11] A new study has shown just how quickly erupting supermassive black holes can shut off star

[00:04:16] formation in big galaxies. The findings reported in the journal Nature are based on new observations

[00:04:22] by the Webb Space Telescope which was able to detect the cold neutral gas which collapses

[00:04:27] in molecular gas and dust clouds to form new stars. See up until Webb observations were only

[00:04:34] really able to see the warm ionized gas. But by using the new data made available from the

[00:04:39] Webb observations, the authors found that more than 90% of the galactic wind is made up of the

[00:04:44] previously invisible neutral gas. Even more shockingly, astronomers found that black holes can

[00:04:50] rapidly quench star formation by explosively removing large amounts of this gas. It's the

[00:04:56] first direct confirmation that supermassive black holes are capable of shutting down galaxies.

[00:05:02] One of the study's authors Rebecca Davies from Swinburne University says the outflows removing

[00:05:07] gas faster than the gas can be converted into stars and that indicates that the outflows

[00:05:12] like they'd have a very significant impact on the evolution of the galaxy.

[00:05:16] Put simply, when star formation is quenched it means a galaxy stopped forming new stars.

[00:05:23] And that represents the transformation between a galaxy that's actively forming stars allowing

[00:05:28] it to grow and evolve and a galaxy that's dead and static. Quenching therefore is a fundamental

[00:05:34] process in the life cycle of stars. The thing is astronomers still don't really understand in detail

[00:05:40] what leads a galaxy to stop forming stars. So Davies and colleagues studied a galaxy more than

[00:05:46] 10 billion light years away using James Webb. We know that actively feeding supermassive black

[00:05:52] holes generate huge creation disks of superheated material around their event horizons. The event

[00:05:58] horizon is the border zone beyond which matter disappears as it falls forever into the black

[00:06:03] hole singularity. But before it passes this event horizon point of no return, the material in

[00:06:10] the creation disk is being ripped apart and superheated by friction and immense gravitational

[00:06:14] forces releasing huge amounts of energy which together with some of the material itself

[00:06:19] is driven by powerful magnetic fields into superluminal jets called quasars, blazars and active

[00:06:25] galactic nuclei depends on which angle you're seeing it. And these jets can then shoot out

[00:06:31] perpendicular to the creation disk close to the speed of light. The new observations show that

[00:06:36] these massive outflows which can be bright enough to be seen on the other side of the

[00:06:40] universe can remove all the gas from their host galaxies in a relatively short amount of

[00:06:44] time thereby causing star formation to cease. Davies says that in the galaxy her and a team

[00:06:50] were studying they found that the outflow rate of the neutral gas phase was about 100 times larger

[00:06:56] than the outflow rate in the ionized gas phase therefore showing a lot of our flowing mass that

[00:07:00] was previously invisible. It shows how Webb can be used to detect a much larger fraction

[00:07:06] of the outflows whereas previous ionized gas observations were only able to detect about

[00:07:11] 1%. Davies says before Webb astronomers were really only scraping the tip of the iceberg when it

[00:07:17] comes to understanding the outflow of mass from a galaxy with an active galactic nuclei.

[00:07:22] What we found with the observations from the James Webb Space Telescope is actually that

[00:07:28] supermassive black holes in the centers of galaxies are able to remove a lot more gas

[00:07:34] from galaxies than we previously thought. So for a long time as you mentioned there have been these

[00:07:40] theories suggesting that black holes in the centers of galaxies are one of the most important

[00:07:47] processes responsible for shutting off star formation. However it has been difficult to find

[00:07:53] observational evidence to support this picture so we've been looking back in time to galaxies

[00:07:59] in the distant universe because that's when they were growing the fastest, that's when most of the stars

[00:08:05] were forming and that's also when we started to seeing a lot of star formation being shut off

[00:08:11] in the most massive galaxies. And so for at least the last 10 years we've known that these galaxies

[00:08:17] do show outflows of gas and that the black hole is able to remove a lot of material however

[00:08:24] these observations suggested that the outflows were not actually strong enough to completely

[00:08:30] shut off star formation. They did remove some fuel but there was still a lot left and so the

[00:08:34] galaxies should have enough material to keep growing for a long time. The difference between

[00:08:39] those results and our new observations with the James Webb Telescope is that with the James Webb

[00:08:45] we are probing colder gas which is more dense and has a lot more mass in the outflow. So

[00:08:52] with James Webb we were able to observe both ionized gas which is warm and can be detected through

[00:08:58] emission lines and also neutral gas which is cooler and requires much higher sensitivity

[00:09:05] to detect so we couldn't see it from ground-based telescopes. And basically we found that this

[00:09:10] cool gas contributes at least 90% of the mass of the outflows which means that these outflows

[00:09:16] were virtually invisible in our previous studies with ground-based telescopes. And so now with these

[00:09:22] new observations we find that the outflows are in fact powerful enough to remove most of the gas

[00:09:30] from the galaxies and thereby shut down star formation. And this process happens very quickly

[00:09:35] too at least in galactic terms. Yes so we think that the star formation quenching can happen

[00:09:40] on time scales of just a couple of hundred million years with the James Webb Telescope data we

[00:09:46] are actually also able to track the history of star formation in the galaxies and so for this one

[00:09:52] particular source that we published in The Nature article we saw that about 200 million years before

[00:09:59] the epoch of observation the galaxy was forming stars at a high rate and then this rate suddenly

[00:10:06] dropped and we think that that sudden drop is associated with an episode of outflow driven

[00:10:12] by the supermassive black hole. When you look that far back in space-time what do the galaxies look like?

[00:10:18] So galaxies back in time have many similar features to the galaxies in the nearby universe.

[00:10:25] When we observed the galaxies with Hubble we first thought that distant galaxies were very

[00:10:32] very clumpy and irregular compared to nearby galaxies. Train records the two. Yes it turns

[00:10:37] out that when you look at them with the James Webb Space Telescope they look a lot more regular

[00:10:42] and part of the reason for that is that Hubble when you are looking at distant galaxies is actually

[00:10:48] seeing the ultraviolet light emitted by the stars because the photons are red shifted

[00:10:53] as they travel from the galaxy to us. And so if you see the light at visible wavelengths that

[00:11:00] means that it was at ultraviolet wavelengths when it was emitted. Now the James Webb Telescope

[00:11:04] because it's an infrared telescope can actually see the visible light emitted from those distant

[00:11:09] galaxies and so the ultraviolet light only traces the very young stars but the visible light traces

[00:11:16] the older stars and the lower mass stars which make up the majority of the galaxies. And so when

[00:11:21] we look at this redder light in the James Webb Telescope the galaxies do look a lot more regular

[00:11:27] and more similar to what we have in the present universe. But the main difference is that

[00:11:32] these distant galaxies are a lot more gas rich. They can often form stars in much clumpier regions

[00:11:40] so they have these very active regions of star formation and they're often a lot smaller because

[00:11:45] they haven't had the time to grow into these large structures that we see today. The fact that

[00:11:49] they're looking so for one of the better term well formed so early in the history of the universe

[00:11:56] must tell you that galaxy formation is starting very early. Yes and this is something

[00:12:02] that we are exploring almost anew with all the observations from the James Webb Space Telescope.

[00:12:08] There have been a lot of observations suggesting that there are very massive galaxies in the

[00:12:13] very early universe and so this is really challenging astronomers to come up with new models to understand

[00:12:20] how large amounts of stars and really big galaxies could form so rapidly so early in the universe.

[00:12:27] Webb has changed the way we see the universe hasn't it? Yes entirely. What do you want to do next?

[00:12:32] Do you want to study more galaxies like this early one? Yes so actually this nature article that we

[00:12:37] published was just based on one galaxy but we have a sample of 150 galaxies all at a similar epoch

[00:12:45] so about 10 billion years in the past and we published a companion paper which looked for

[00:12:51] similar cold outflows in this entire sample and we showed that these outflows are actually

[00:12:56] relatively common across high mass galaxies and so this provides another piece of evidence to

[00:13:02] suggest that this black hole driven outflows could be an important mechanism for shutting down star

[00:13:07] formation across the entire population of galaxies not just in one specific galaxy. Now

[00:13:12] our team has been awarded more observations on the James Webb Telescope to get more detailed

[00:13:19] information about these outflows because so far we've been able to identify them and measure

[00:13:25] their mass but we also want to measure how much gas is left in the galaxy not just how much is

[00:13:31] outflowing and so we're going to be going back and looking at the same galaxies but with higher

[00:13:35] resolution more detailed information to be able to understand how the rate of outflowing material

[00:13:42] is related to how much gas is left in the galaxy and this would really be the cherry on the

[00:13:47] cake if we could show that the amount of gas left in the galaxy decreases as the star formation

[00:13:52] rate decreases. When you look at the wavelengths of light through web and you're seeing these stretched

[00:13:59] wavelengths what types of gases are you seeing? With the James Webb observations detecting the

[00:14:05] neutral gas what we are studying is sodium absorption actually so there's a there's an

[00:14:11] absorption line of sodium in the rest frame optical and we detect that because it's a

[00:14:17] strong absorption feature and it happens to land at the correct wavelength so that it's within the

[00:14:23] spectrum of James Webb. This is a feature that has been studied in detail for closer galaxies

[00:14:30] through things like the flowing digital sky survey but it was not really detected in distant

[00:14:35] galaxies before James Webb because it was virtually impossible to detect any kind of

[00:14:41] absorption line because you need very sensitive instruments in order to detect the continuum

[00:14:48] from the stars basically. That's Dr Rebecca Davies from Swinburne University and this space time

[00:14:56] still to come China successfully launches its Changi Six sample return mission which will

[00:15:01] attempt to collect the first samples ever from the lunar far side and later in the science

[00:15:06] report a new study finds that olive oil has been linked to a lower risk of dementia related death

[00:15:13] all that and more still to come on space time. China has successfully launched its Changi Six

[00:15:35] sample return mission which will attempt to collect the first lunar rock samples from the

[00:15:39] far side of the moon. The flight aboard a Long March 5 rocket lifted off from the

[00:15:44] Wangchang satellite launch center Henan island in the undisputed region of the South China Sea.

[00:15:50] The lander includes scientific instruments from France Italy and the European Space Agency.

[00:15:56] The mission is also carrying a Pakistani CubeSat which is deployed into Earth orbit before beginning

[00:16:02] its lunar trajectory. Changi Six follows on from the successful Changi Five lunar sample return

[00:16:08] mission it collected moon rocks from the lunar near side. Changi Six will target the massive

[00:16:13] South Pole Atkin Basin the solar system's largest impact crater. It's not China's first visit to

[00:16:20] the lunar far side. Back in January 2019 the Changi Four mission was the first spacecraft to land

[00:16:27] on the lunar far side also targeting the South Pole Atkin Basin. The 8,350 kilogram

[00:16:34] Changi Six includes an orbiter which undetects the journey to the moon back attached to the

[00:16:39] orbiter is a lander which will descend down to the lunar surface where it will use the square

[00:16:44] div instruments to undertake a detailed analysis of the area. It will also collect up to 2 kilograms

[00:16:50] of lunar soil and rocks or regolith for the sample return to Earth. Those samples will be placed

[00:16:56] into an ascent vehicle mounted on top of the lander which will launch back into lunar orbit

[00:17:00] where it will run the ver with the orbiter and place the samples in an Earth reentry module

[00:17:05] attached to the orbiter. The orbiter will then return them to near Earth space where the reentry

[00:17:10] module will be jettisoned to bring the samples back down to the Earth's surface. Now if this is

[00:17:15] successful it'll be the first mission to return samples from the lunar far side to the Earth.

[00:17:21] The South Pole Atkin Basin has intrigued scientists for years because of its geological

[00:17:26] composition and potential water ice deposits. It's a region which can provide scientists

[00:17:32] with new insights into the moon's history, its evolution and its geological processes.

[00:17:38] See the lunar far side remains one of the least understood regions of the moon due to its unique

[00:17:42] location and the challenges associated with direct communications from Earth. Beijing solved

[00:17:48] this problem with Changi-4 by also having a communications satellite placed in orbit

[00:17:53] around the moon to relay signals from Changi-4 back to mission managers.

[00:17:58] Another important aspect of the Changi-6 mission is that it's also placing China on

[00:18:03] course to potentially be the first nation to undertake a Mars sample return mission.

[00:18:08] Now right now that flight slated for 2030 as part of the Tianwen-3 mission. Tianwen-3 will

[00:18:15] include a lander, an ascent vehicle, an orbiter and a reentry module. The mission slated to

[00:18:21] launch aboard two Long March 5 rockets also from Wing Chang. The lander and ascent vehicle

[00:18:26] will travel the Mars on one rocket landing on the surface. Final sites have to be chosen.

[00:18:32] The other rocket will carry a Mars orbiter and Earth's reentry module and also act as a relay

[00:18:37] station conveying communications between mission managers and the spacecraft on the ground.

[00:18:43] It'll wet in orbit for the collection of the samples. After collecting samples of

[00:18:47] Martian regolith, the ascent vehicle will launch and fly back into orbit,

[00:18:51] rendezvousing with the orbiter with a return journey to Earth where the reentry module

[00:18:56] will be jettisoned to land on the Earth's surface. Now while Beijing is taking care of business,

[00:19:01] the much heralded joint NASA-ESA Mars sample return mission designed to collect samples

[00:19:06] currently being gathered by NASA's Mars Perseverance rover and Jezero crater has been

[00:19:11] forced to undertake a major revamp because of funding cuts. And that's placed the 2028

[00:19:16] launch date on hold until the shape of the new mission has been finalized and approved.

[00:19:22] It means that Beijing may well overtake Washington to become the first to collect

[00:19:26] samples of the Martian surface and bring them back to Earth. This, Space Time.

[00:19:48] And time out to take a brief look at some of the other stories making news in science this week

[00:19:52] with a science report. A new study claims that consuming olive oil could be linked to a lower

[00:19:58] risk of dementia-related death, especially in women. A report in the Journal of the American

[00:20:03] Medical Association looked at data from 92,383 adults observed over 28 years.

[00:20:11] They found that the consumption of more than 7 grams of olive oil a day was associated with a 28%

[00:20:16] lower risk of dementia-related death compared to those who never or really consumed olive oil.

[00:20:22] And the authors say these findings remain consistent even when adjusting for diet quality.

[00:20:28] The authors estimate that substituting 5 grams per day of margarine or mayonnaise with olive oil

[00:20:34] could also be associated with lower dementia-related death risk but not when substituting butter or

[00:20:39] other vegetable oils. The researchers stress that while this study cannot prove a direct

[00:20:44] cause and effect, the findings do extend current dietary recommendations for choosing

[00:20:49] olive oil and other vegetable oils for brain health. The 2024 European Society of Clinical

[00:20:57] Microbiology and Infectious Diseases Global Congress has been warned that as the planet

[00:21:02] heats up, an additional 4.7 billion people around the world are predicted to be at risk of malaria,

[00:21:08] dengue fever and other mosquito-borne diseases by the turn of the century.

[00:21:13] The conference was told that the worsening of missions and increased population growth

[00:21:18] will see rates continue to grow at current rates spurred on by global warming and urbanization.

[00:21:24] Scientists warn that mosquito-borne disease outbreaks are set to spread across currently

[00:21:28] unaffected parts of northern Europe, Asia, North America and Australia over the next few decades.

[00:21:35] The Congress was also told that improved surveillance and early warning systems

[00:21:39] are now urgently needed in order to tackle this now almost global phenomenon.

[00:21:44] They say the most effective way to reduce the risk of these diseases spreading to new areas

[00:21:49] is to dramatically curb carbon emissions now. The projection suggests limiting global warming

[00:21:55] to an ambitious goal of just 1%, which is looking increasingly unachievable, would

[00:21:59] nevertheless reduce the number of additional people at risk by 2021 to 2.4 billion.

[00:22:06] A new study has confirmed what's been reported anecdotally for months now.

[00:22:10] Artificial intelligence not only lies and makes stuff up,

[00:22:14] but it's also getting really good at tricking people and being deceptive.

[00:22:18] The findings reported in the journal Patens shows that AI's talent for deception is becoming

[00:22:23] quite extraordinary. Studies authors warn that AI's trained to be helpful and honest have

[00:22:29] instead learned to be masters of deception. Metis AI, that's Facebook, was tasked with

[00:22:36] winning a game of diplomacy and did so dishonestly. The authors note that other AI systems have

[00:22:42] demonstrated the ability to bluff or fake attacks in strategy games or misrepresent their

[00:22:47] preferences to gain an advantage in economic negotiations. Then there's the AI that tricked

[00:22:53] a human into telling it which images to select in a capture I'm not a robot test.

[00:22:58] And the AI that invented an entire non-existent scientific study in a

[00:23:03] non-existent peer reviewed journal complete with equally non-existent references.

[00:23:08] And still common with Google is the AI that's refusing to acknowledge the achievements of

[00:23:13] white males, showing George Washington as black and Neil Armstrong, Buzz Aldrin and Michael Collins,

[00:23:19] the crew of the Apollo 11 mission as multigracial, with one of them possibly being a woman.

[00:23:25] The researchers of the study say this is leading to breakthroughs and deceptive AI

[00:23:29] capabilities. So it's probably best if we never have the nuclear codes over to the AIs,

[00:23:34] even if they swear they'll keep them secret. So I guess you can say that Cyber Diamond

[00:23:40] Skynet are looking pretty real right now, aren't they? Back in 1966, some 300 schoolkids and staff

[00:23:48] from Melbourne's Westall High School witnessed something in the sky above a nearby field that

[00:23:53] totally blew their minds. Now at the time they claimed what they had seen was a flying saucer or

[00:23:59] maybe several. Back then they claimed the incident was being covered up by authorities.

[00:24:04] Now 62 years later, they're still waiting for answers. They say the truth is out there.

[00:24:11] Tim Endham from Astrian Skeptic says the so much confusion about that infamous April 6th event,

[00:24:17] the exact details are a real mishmash but that seems to be the standard for most UFO sightings.

[00:24:23] The Westall UFO encounter was an incident in a suburb in the southeast of Melbourne, Victoria,

[00:24:29] which took place in 1966 near a Westall High School in which reports vary a little bit and

[00:24:36] that's part of the problem. It's often part of the problem with UFO stories but particularly in

[00:24:40] this one the witnesses who are largely kids, high school kids, are now trying to get confirmation

[00:24:45] of what they saw which is fair enough they've been waiting how many years, 60 years or

[00:24:49] something for their witness accounts verified. There are various problems with this. What happened

[00:24:53] was that depending on which story you believe, a kid from outside rushed into a school room and

[00:24:58] told the teacher there's a flying saucer or some such word they use outside so the kids in the

[00:25:04] class all went running outside including the teacher and supposedly other kids joined them

[00:25:08] whether it was doing a recess or they just ran out of the classes because they got a little

[00:25:12] excited or it might have been a class doing PE physical education outside the school who

[00:25:18] saw it first and there might have been more than one teacher and it gets very very messy and what

[00:25:23] the reports say was that they saw one or several could be three might be more objects in the sky

[00:25:29] that were perfectly round or cigar shaped and that one of them landed just over behind some

[00:25:34] trees or it didn't and some kids ran down and one of them touched the flying saucer and got

[00:25:39] badly burnt or it didn't and one kid was apparently taken away by the authorities and

[00:25:44] never came back or didn't and the trouble is it goes on and on like this. There are,

[00:25:50] depending on the witness you talk to, you get different variations certainly initially when

[00:25:54] they're interviewing people and the teacher, the main teacher who went out there to have a look

[00:25:58] has sworn recently that there was only one object because other people, witnesses now in their

[00:26:03] 70s swore there were three and they're different shapes. One of the problems with witness

[00:26:07] accounts is they're unreliable and they're more unreliable but the greater the time

[00:26:11] between the event and they're getting their witness accounts. This is now 60 years basically so

[00:26:16] there's two things about witness account they've developed, they evolve, people elaborate on them,

[00:26:21] they make up stuff to go with it, they think it's a true memory but it's often just

[00:26:25] added to or if they are discussing it with each other as the students, ex-students have done

[00:26:32] because they've often got back together again years after to discuss what they saw etc they tend

[00:26:37] to amalgamate their events and everyone endorses each other and so what once it becomes the group

[00:26:43] record which is amazing because when they were first witness they had all these variations on

[00:26:48] what actually happened and yet now they're trying to sort of convince everyone that it was

[00:26:51] the grandest thing since Adam was a boy. In fact it is actually quite a famous UFO case,

[00:26:56] some people say it's more famous overseas than it is in Australia. Well the Air Force could

[00:27:00] get involved in the research didn't they to see if there's any... Well that's the story,

[00:27:05] that's the story, there's no official comment on it. Right now that's the story that the Air Force

[00:27:10] ambulance police you name it everyone went down there that they supposedly told the kids do not

[00:27:15] talk to anyone about this. This one kid who got burned was taken away never seen again someone

[00:27:19] else said actually that kid was transferring to a different school anyway and that was why

[00:27:22] they weren't seen again that the headmaster told them during a recess you will not talk

[00:27:26] about this it never happened some suggested he was a strongly religious person and didn't

[00:27:30] like the idea of UFOs or that he might have done that he might have told them you know

[00:27:34] you were so rubbish you know don't bother talking about it and suddenly it becomes an order from on

[00:27:38] high and suddenly it becomes an order from the men in black or it comes from the authorities etc.

[00:27:43] So this is a classic case of UFO stories developing and making it very hard to get back to the

[00:27:49] basics what you've got to do is look for interviews done at the time even then they're

[00:27:54] not necessarily guaranteed to be accurate but look at the ones at the time because the ones

[00:27:58] that are talking about now are primarily pretty useless for the various reasons I've said and the

[00:28:02] ones that were done at the time especially of the teacher say a different thing to what a lot of the

[00:28:06] witnesses are now saying. UFO cases it always comes down to the evidence witness accounts for

[00:28:11] one thing but as any judge and jury will tell you certainly a judge and the police will tell

[00:28:16] you witness accounts are very unreliable because they change well scientists will tell you that

[00:28:20] too witness accounts are unreliable because the brain naturally augments things and

[00:28:25] leaves things out and puts new things into full the gap that's just the way the human mind works.

[00:28:30] Yes in the same way as someone can say oh yeah I was there too and they weren't right because

[00:28:35] they've heard a story and they put themselves in that position to say they saw it as well

[00:28:38] often the case they weren't and you end up with an argument saying you weren't there yes I was.

[00:28:42] Memory is a very poor thing actually unfortunately man that's why witness accounts in the court

[00:28:46] of law can be a very difficult area to maintain accuracy anyway this is typical of UFOs you

[00:28:51] look for the evidence there is no evidence apart from eyewitness accounts there is nothing else

[00:28:55] there was suggestions that there were balloons one balloon more balloons who knows in the area

[00:29:00] uh weather balloons so decent size reflecting in the sunlight looks like shiny surface others

[00:29:05] saying it definitely wasn't a balloon I've seen a balloon it's nothing like a balloon tying this

[00:29:09] one down this famous case is very difficult and the people who are witnesses there are saying

[00:29:14] they're sort of frustrated at not having evidence to supporters or you know confirmed it right

[00:29:19] authorities and that there are a lot of other alternative explanations it's classic you'll

[00:29:23] be having it out in the US with the world these sort of UFO cases when they've got films and videos

[00:29:27] they're quite easily debunked and the rest is saying I know someone who knows someone who has the

[00:29:32] evidence or you know who has seen aliens or has seen flying saucers etc and no one ever produces

[00:29:38] it and they have been talking for 70 years since some of the very earliest um you know

[00:29:43] sort of UFO sightings that the proof is going to be just around the corner just around the

[00:29:48] corner we're going to have definitive evidence of these things and we've been waiting a long time

[00:29:52] to get definitive evidence to come up and they're still saying they're still making the same claim

[00:29:56] and I will make a bet that we it would be a number of years still before we have definitive

[00:30:00] evidence that's Tim Endham from Australian Skeptics and that's the show for now

[00:30:21] space time is available every Monday Wednesday and Friday through Apple Podcasts

[00:30:26] Stitcher, Google Podcasts, Pocket Casts, Spotify, A-Cast, Amazon Music, Bites.com, SoundCloud,

[00:30:34] YouTube, your favorite podcast download provider and from spacetimewithstuartgarry.com

[00:30:41] Spacetimes also broadcast through the National Science Foundation on ScienceZone radio

[00:30:45] and on both iHeart Radio and TuneIn Radio and you can help to support our show by visiting

[00:30:51] the spacetime store for a range of promotional merchandising goodies or by becoming a spacetime

[00:30:57] patron which gives you access to triple episode commercial free versions of the show as well

[00:31:02] as lots of bonus audio content which doesn't go to air access to our exclusive Facebook group

[00:31:07] and other rewards just go to spacetimewithstuartgarry.com for full details and if you want more

[00:31:14] spacetime please check out our blog where you'll find all the stuff we couldn't fit in the

[00:31:18] show as well as heaps of images, news stories, loads of videos and things on the web I find

[00:31:23] interesting or amusing just go to spacetimewithstuartgarry.tumblr.com that's all one word and

[00:31:30] that's tumblr without the e you can also follow us through at stewartgarry on twitter

[00:31:35] at spacetimewith stewartgarry on instagram through our spacetime youtube channel and on

[00:31:41] facebook just go to facebook.com forward slash spacetimewith stewartgarry you've been listening

[00:31:47] to spacetimewith stewartgarry this has been another quality podcast production from bites.com