Hidden Wonders: Discovering the Mysterious Garo 04 Star Cluster

[00:00:00] [SPEAKER_03] This is Space Time series 29 episode 121, full broadcast on the 9th of October 2026. Coming up on Space Time, a mysterious star cluster discovered hidden deep inside the Milky Way's disk, the truth about Nazi Germany's infamous nuclear bomb project, and the chronic need for dark skies. All that and more coming up on Space Time.

[00:00:26] [SPEAKER_00] Welcome to Space Time with Stuart Gary.

[00:00:46] [SPEAKER_03] Astronomers have discovered a mysterious star cluster hidden in the crowded galactic disk of the Milky Way galaxy, some 32,800 light years away. A report on the pre-pressed physics website Archive.org claims the object, which has been named Garo 04, was first identified as an unusual collection of stars in observations by the VISTA variables and the Via Lactea and its extension, or a triple VX survey.

[00:01:12] [SPEAKER_03] The inner regions of the Milky Way galaxy, especially around the galactic plane and bulge, are crowded with stars, dense gas and dust lanes, all rich in star-forming activity. And the stars in these regions are traces of the Milky Way's chemical history and evolution. So examining these regions can reveal a lot about our galaxy's past mergers. The problem is, dust blocks out optical wavelengths.

[00:01:37] [SPEAKER_03] So astronomers need to switch to infrared observations in order to peer through this thick cloak of dust. Near-infrared surveys, like the triple VX, have revealed numerous previously hidden open and globular star clusters in these dust lanes. The study's lead author, Lisa Garo from the European Southern Observatory in Chile, says the Garo 04-star cluster was detected by visually spotting a prominent clump of red giant stars in the triple VX infrared imaging.

[00:02:05] [SPEAKER_03] Further analysis using multiple survey databases, including the third guide data release, provided precise positions and motions of these stars. And the two-mass survey provided supplementary infrared photometry. Cluster member stars all move together through space in a similar direction or speed. So the authors used this shared proper motion to statistically separate members of the cluster from unrelated foreground and background stars.

[00:02:32] [SPEAKER_03] That left just 613, or around 29%, of the original 2,145 stars in the field as likely members of the cluster. Garo and colleagues estimate the cluster is around 5 billion years old, with lower metallicity than our Sun. Astronomers refer to all elements other than hydrogen and helium as being metals. The cluster moves on a nearly circular, low-tilt orbit around the galactic centre, staying close to the galactic disk at all times,

[00:03:01] [SPEAKER_03] thereby confirming that it is a disk cluster rather than a halo or bulge object. Garo 04 is too old to be a typical young open cluster. But at the same time it's not old, or metal poor enough, to be a classic globular cluster. And there's the weirdness. It joins a small but growing list of similar puzzling in between clusters, which have been found in other surveys in recent times.

[00:03:25] [SPEAKER_03] Garo says the next step will be to undertake a more detailed chemical analysis, and better disentangle the real nature of the cluster, classifying it as either a globular cluster, an open cluster, or some sort of in-between intermediate class object. This is Space Time. Still to come, the truth about Nazi Germany's infamous nuclear bomb project. And our chronic need for dark skies. It's more than just astronomy.

[00:03:54] [SPEAKER_03] All that and more coming up on Space Time. The Manhattan Project was not just a quest to build a nuclear bomb, it was a quest to build a nuclear bomb before Nazi Germany completed theirs. One route to building an atomic bomb is to build a nuclear reactor to produce fissile material. But it's always been unclear how close the Nazis were to creating their own reactor.

[00:04:23] [SPEAKER_03] Their final attempted reactor, the B-8 pile, used heavy water as a neutron moderator. The only source of heavy water at the time was the Norsk hydro plant in Vermont, Norway, which was controlled by the Nazis from April 1940 until its destruction by Allied saboteurs and bombing in November 1944. Now, the Nazi nuclear bomb project led by Werner Heisenberg claimed that the B-8 pile was just short of criticality when American forces found and dismantled it in 1945.

[00:04:54] [SPEAKER_03] After the war, Heisenberg and colleagues like Carl Friedrich von Wiesensacker claimed they had understood the physics of an atomic bomb, but deliberately steered the Uranium Club project towards a uranium machine reactor rather than an atomic weapon. They claimed they had kept the effort under scientific control, avoiding the push for a massive industrial program that could have produced an atomic bomb for Hitler and, in some accounts, implied passive resistance or reluctance rooted in moral scruples.

[00:05:21] [SPEAKER_03] But that claim has been largely dismissed as a post-war rationalization. There is virtually no real supporting evidence, and mainstream historical consensus attributes the German nuclear program's failure mainly to scientific incompetence and misjudgments by Heisenberg. There are also resource constraints, organizational problems and, luckily, a low priority from the regime rather than any real moral resistance from Heisenberg or his cohorts.

[00:05:47] [SPEAKER_03] The simple fact is Heisenberg and colleagues made significant errors in their calculations on the critical mass and practical requirements. The evidence shows the program was a genuine weapons-related effort that simply stole due to shortcomings, not sabotage. Now, Timothy Keough and colleagues from the University of Maryland have analyzed two cubes of natural uranium from that project, as well as historical records, technical reports, correspondence and other archival material.

[00:06:18] [SPEAKER_03] Using all these resources, they've concluded beyond doubt that, to go critical, the B-8 pile would have required twice as much uranium as they had, and twice as much heavy water as was produced by the Norsk's hydro plant during the entire war. The graphite available in German-controlled areas would simply not have been suitable for a substitute moderator. According to the authors, given the design that the Germans were using, they simply did not have the materials needed to build a working atomic bomb.

[00:06:46] [SPEAKER_03] The slowing of Germany's nuclear bomb project wasn't because of resistance by Heisenberg, but incompetence. This is Space Time. Still to come, the chronic need for dark skies. And later in the Science Report, a new study confirms that kids exposed to adversities in childhood face worse outcomes in life when reaching adulthood. All that and more still to come, on Space Time.

[00:07:26] [SPEAKER_03] The Royal Astronomical Society is demanding urgent action to address the damage light pollution is doing to astronomy, to human health, to biodiversity of the planet and to the natural environment. It follows an influential conference on the issue hosted by the Society, where compelling evidence was presented about the significant impacts of artificial light at night. Exposure to light pollution and lack of natural sunlight can lead to poor metabolism

[00:07:51] [SPEAKER_03] and the development of diseases such as type 2 diabetes, obesity, dementia, Parkinson's and retinal problems. There is also evidence that suggests it directly impacts on a person's mood and increases the prevalence of both depression and anxiety. And it's not just humans who are affected. The impact of artificial light on the natural environment is also highly significant. It can alter habitats, fragment ecosystems and accelerate biodiversity loss,

[00:08:19] [SPEAKER_03] especially among the many nocturnal species which rely on natural darkness to survive. Caterpillar populations have declined by 52% in areas exposed to street lighting. And evidence shows around a third of insects drawn to artificial light sources die due to exhaustion, predation or disorientation. They also point out that marine biodiversity suffered as well. Light pollution also reduces plant-pollinator interactions by up to 62%,

[00:08:48] [SPEAKER_03] significantly impairing pollinization and plant reproduction. Of course, artificial light and light pollution also compromises the view of the night sky for both astronomers and the general public. And to counter this, the Royal Society is calling for artificial light at night to be legally recognized as a pollutant. The Society believes night time should be recognized as an integral part of the natural environment,

[00:09:13] [SPEAKER_03] requiring protection on par with daytime activities in order to strengthen conservation efforts. They want to see night time lighting used only as needed and when it is needed using warmer colored lighting. Tanya Hill, Senior Curator of Astronomy at the Melbourne Planetarium, says light pollution is a growing problem globally. We need more dark sky areas.

[00:09:35] [SPEAKER_01] It breaks my heart. I grew up in Liverpool and Western Sydney and I remember my dad showing me the Magellanic clouds and the Milky Way from my backyard. That was one of the things I would go out and you could just see that. I remember spending time up in the Blue Mountains with my cousins just lying on the trampoline absolutely lost in the gorgeous skies. And yeah, that light pollution is just encroaching on us more and more. And I think the scary thing, kids growing up today who just don't have that access to the sky.

[00:10:04] [SPEAKER_01] I mean, we're told that more than a third of the Earth's population can't see the Milky Way from their home. And about 80% of the Earth's population don't have access to dark skies. Those figures are just alarming. And it's more the fact that if you've never seen it, you don't know what you're missing. And that's what really concerns me.

[00:10:23] [SPEAKER_03] I'm told that when there's a blackout in the United States, emergency services get phone calls from people saying there are lights in the sky.

[00:10:31] [SPEAKER_01] Oh no, oh no, there are those stars, those beautiful stars that you see. Although that does also make me think because we can talk about light pollution and the fact that we're causing this glow that is fading out to the gorgeous light of the stars. But then there's also another type of pollution which we're doing with all the satellites that are up there. I've had quite a few of my colleagues who have gone away recently with the holidays and all of them have said they've gone out to look at the stars.

[00:10:57] [SPEAKER_01] And they were amazed by the number of satellites that they're now seeing. It has just grown so much.

[00:11:04] [SPEAKER_03] The trains of Starlink satellites is quite ridiculous. There are so many of them. It's not just Starlink now. We've got Blue Origin starting their network. There are others out there as well.

[00:11:15] [SPEAKER_01] There are just so many. Absolutely. So I just recent count is that there's about 15,000 satellites in orbit and 10,000 of those are the Starlink SpaceX satellite. That just is mind boggling to me that what we're doing up there for our skies and what that also means. I remember hearing last year there was a great Indigenous panel at Melbourne Museum that was speaking about Indigenous space futures.

[00:11:41] [SPEAKER_01] And Professor Dean Sanders, he was saying how he was out on country waiting with an elder who was going to share a story with him being told about from the stars. And he started the story and a satellite went by. And it was like, oh, that was fine. They stopped for a moment, let the satellite pass. The elder started to repeat their story. And there was another satellite and another satellite. And I think that's the issue. It seems that we always tend to take things to extremes, don't we? It was just the odd satellite and you waited for a moment.

[00:12:09] [SPEAKER_01] But the fact that there were just more and more coming and the story, the knowledge couldn't be shared. And it just brought them both to tears.

[00:12:17] [SPEAKER_03] There are some things we can do about this. We can change the way our streetlights are designed. And that's starting to happen, but not nearly fast enough. And it won't do enough either because you still have tall buildings with lots of fluoros and neons and LEDs. But there's also areas that are set aside that are now reserved, aren't there?

[00:12:34] [SPEAKER_01] Yeah, absolutely. And look, this is the thing about light pollution. We actually know how to fix other types of pollution, much harder to fix this one. And all we need to do is turn off the light. So it can be, there's just a few simple things you can do. You can use warm redder light rather than the bright white blue light, which affects our eyes so much more. I know starting out in astronomy, one of the first things that as a hobby and an amateur astronomer where I began, the first thing you learn is you cover your torch with red cellophane to keep your night vision.

[00:13:03] [SPEAKER_01] So yeah, you can change the color of the light you use. You use motion sensors. So to make sure that the light is only there when it's needed, direct light for where it's needed and shield it. So it isn't creating this glow going up in our skies. I was actually just trying to look. I know a few years back, Melbourne put forward a policy based on what they're doing in France, which France is one of the countries that has been able to reduce their light pollution.

[00:13:26] [SPEAKER_01] And part of that is as simple as dimming or turning off unnecessary lighting between midnight and sunrise. But as you mentioned, there are, we are lucky in Australia. We do have large areas in the country that have, still have some lovely dark skies. And one of the things that we have done is that across the country, there are eight dark sky places. And these are certified by the Dark Sky Alliance. It's an international board.

[00:13:55] [SPEAKER_01] There's an Australian section that does that. And so this varies from, there's an urban night sky place, which is in Palm Beach on the edge of Sydney. We're all the way up to the Warrumbungal Dark Sky Park, which is out near Coonabarabran, where our professional telescopes still operate. And that is a place that we really want to preserve the dark sky, both for the visitors and the people who live there,

[00:14:20] [SPEAKER_01] but also for the astronomers to be able to still have access to try and work out the mysteries that we want to discover about the universe.

[00:14:27] [SPEAKER_03] The sad news is even at Coonabarabran, if you look to the east, you can still see the glow of Sydney, even though it's...

[00:14:34] [SPEAKER_01] Absolutely.

[00:14:34] [SPEAKER_03] ...hundreds of miles away.

[00:14:36] [SPEAKER_01] And it just, it's getting bigger and bigger as the city expands out, that's right.

[00:14:41] [SPEAKER_03] That's Dr Tanya Hill, the Senior Curator of Astronomy at the Melbourne Planetarium at Museums Victoria. And this is Space Time. And time now to take another brief look at some of the other stories making news in science this week with a science report.

[00:15:11] [SPEAKER_03] A new study has shown that kids are exposed to adversities in childhood, face far worse outcomes in life when reaching adulthood. The findings were reported in the Journal of the American Medical Association.

[00:15:22] [SPEAKER_03] Based on research involving some 1,850 participants showed that being exposed to adversities such as childhood abuse, neglect, witnessing domestic violence, living with drug addicts or alcoholics, living with someone with a severe mental illness, having parents who have split up, or having a member of your household incarcerated while growing up, is linked to elevated rates of depression, post-traumatic stress disorder, suicidal tendencies, interpersonal violence, low scores at school, and using illicit substances when reaching adulthood.

[00:15:52] [SPEAKER_03] The authors found varying grades of effects depending on how many adversities a person had experienced during childhood, with specific types such as emotional abuse, sexual abuse, witnessing domestic violence, and discrimination being more consistently linked. A new study has confirmed that the more ultra-processed foods you eat, the higher your risk of getting chronic diseases like heart conditions, diabetes, and cancer.

[00:16:18] [SPEAKER_03] The findings reported in the Journal of Family Medicine and Community Health are based on analysis of 51 previous studies involving some 9 million people. The analysis also found that eating more such foods increase your risk of death. Ultra-processed foods include many packaged snacks as well as frozen meals. They tend to be less nutrient but higher in energy, and they contain multiple additives that may combine to affect health.

[00:16:46] [SPEAKER_03] Marine scientists have discovered that an endangered species of sea cucumber can live for decades with some animals living more than 100 years. The findings reported in the journal Science are based on the first of its Chi-Genetic Mark Recapture Study. The authors suggest that black teatfish sea cucumber populations recovered much more slowly than previously thought, and this had implications for commercial fishery catch limits.

[00:17:12] [SPEAKER_03] Ohio's Night Stalkers Bigfoot Research Group claims the Buckeye State is experiencing a population boom of Bigfoots. The group claims Sasquatch is making a comeback after half a century of silence. Ohioans are reporting a huge increase in eerie howls, screams and hulking footprints scattered primarily between Akron and Youngstown in the state's northeast. The skeptics Tim Mendham says believers are describing creatures between 6 and 10 feet tall, completely covered in dark fur.

[00:17:42] [SPEAKER_02] In the list of American states which have claimed Bigfoot, Ohio is number 4. Obviously Washington State, Oregon State are up there, probably California as well. So you know, mainly on the west coast. Ohio, moving a bit inland, it's ranked 4th in the nation. And recently, there has been a bit of a Bigfoot flap going on. Not seen since 1978, apparently. And therefore, a lot of people are claiming, I know what I saw, which is classic positive, confident claim, which gets knocked down pretty quickly often.

[00:18:07] [SPEAKER_02] And they're suggesting that Ohio is becoming, or certain parts of Ohio, are becoming sort of hotbeds of breeding populations. Now, that's often the thing that's forgotten in a lot of these cryptid monster claims, is that you've got to have a breeding population for it to survive. One animal, Loch Ness Monster, is not going to last forever. And you've got to have a breeding population of a certain size without being interbreeding within sort of the family. You actually have to have quite a few. There's a whole bunch of people who supposedly have seen this family, this group, individuals, whatever.

[00:18:34] [SPEAKER_02] They've seen, heard noises, eerie howls, as they say, and footprints about the size of a human, a large human. And that's obviously, you know, compulsive evidence that these things exist. People say, I've never heard a howl like that. Well, perhaps you haven't heard a howl like that. It doesn't mean it's a Bigfoot. I've never seen footprints that big. But I mean, no one's taking a photo of this huge population of Bigfoot. There's just been a flat, which tends to happen when one or two people start seeing things, others get in the mood to see things.

[00:18:59] [SPEAKER_02] Not to say they're faking or anything like that, but they just interpret any strange thing as, oh, the explanation is Bigfoot or Loch Ness Monster or flying saucers or whatever. And in this case, they seem to be up around northeastern Ohio. One of the people who made a claim, a scientist who's an investigator of these things, made a curious claim that when talking about these eerie noises and screams and howls, he said, quote, some of these screams pegged higher than a baboon on the spectrograph. Your listeners will be knowing that spectrograph is an instrument for measuring light.

[00:19:29] [SPEAKER_02] So I don't know how you measure a howl or a scream on an instrument that measures light, but it sounds good. It sounds science-y. But you wonder, this is a guy who's a chief researcher or a serious researcher who's been doing it for years, saying that sort of thing is just what? It makes you wonder about the quality of the people and therefore the quality of the evidence of these things. And again, no real evidence.

[00:19:46] [SPEAKER_03] Increases in Bigfoot sightings constantly correlating almost exactly with increases in black bear populations.

[00:19:52] [SPEAKER_02] My goodness, you're such a cynic. When someone takes a photo, the finity photo, everyone carries a high-quality camera in their pocket, a movie camera in their pocket. Perhaps these sightings are too fleeting. If they're fleeting, you can't really trust what you're seeing with your eyes, even though they'll say, I know what I saw. If they're not fleeting, get your camera out, get your phone out and take a photo. But no, I'm too scared. It's such a thing. I watched this thing for minutes and I forgot to take my second photo.

[00:20:16] [SPEAKER_03] That's the skeptics Tim Mendham and this is Space Time. And that's the show for now.

[00:20:38] [SPEAKER_03] Space Time is available every Monday, Wednesday and Friday through Bytes.com, SoundCloud, YouTube, your favorite podcast download provider and from Space Time with Stuart Gary.com. Space Time is also broadcast through the National Science Foundation on Science Zone Radio and on both iHeart Radio and TuneIn Radio. And you can help to support our show by visiting the Space Time store for a range of promotional merchandising goodies.

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[00:21:25] [SPEAKER_00] This has been another quality podcast production from Bytes.com.