#449: 20,000 Black Holes, Polaris Dawn's Spacewalk & New Horizons' Deep Dive

Hello again, thanks for joining us on a new episode of space That's My name is Andrew Dunkley, your host, and it's good to have your company. And coming up on this episode, we've got some fascinating stories as always, and one is about a possible swarm of black holes that might have been discovered in a rather well known region of space too. I might add they thought there was one, now they think there might be twenty thousand. I'm not exaggerating. We're also going to look at the Polaris Dawn mission. Now, by the time this podcast is released, it may well have happened, but it might not, just depends on technical issues. They're sitting on the platform at the moment playing scrabble, waiting for things to get fixed and the pufu valves to be unvalved and all that sort of thing. We also look at the New Horizons mission. It's eighteen years long now and nine years since it did its I buy Pluto, but it's still working. What's it working on? Darkness? That's all coming up on this episode of Space Nuts. Fifteen seconds in Channel ten nine ignition. Squench Space Nuts or three. Two red ones Space Notes as then report it feels good and joining us again to unravel all of that and much much more is Professor Fred. What's an hello thread? Hello Andrew. Unraveling is our business. We're pretty good at raveling as well, especially when it comes to things like headphone leads and things of that sort. Yes, I've got one of those stretchy ones. There you go it. It does a good job, except it keeps getting in the wrong place and it's a bit annoying. But it can't go wireless. You can't go bluetooth through this panel I've got because of the time delay. Just to make things difficult, So you'll talk to me and I wan't hear it for a second and a half, which is. Not you know, that's the deal. It might be going via the moon, could be from you from your desktop to your headphones via the moon. That would be more like two and a half seconds. Yeah. Well, when I bought them, it said if you if you choose to go bluetooth, you may discover that it doesn't work the way you want it to. And that's exactly what happens. Interesting, So it's not all bells and whistles, not all perfect. Tell you what else is in perfect? Well, the weather's been perfect lately, but so's the hay fever. It's Jean ripping through. Us at the moment. My word, Yeah, yep, I'm a terrible sufferer. And I thought it was just because of where we lived. So when we went to England many years ago and got off the plane, I wasn't even off the Gangway or the skybridge or whatever call it, and I was sneezing. I thought, oh no, I thought I escaped all this by coming to the exact opposite side of the planet. But no, it just got me. So now I know it doesn't matter where I am. I'm going to get hay for you if there's pollen in the air. Quite so, I'd like someone to do a study on why it develops later in life because I never had it as a kid. No, I did, neither. Neither did Jeordie. As you know he loves to contribute, does Jeordie, Yes he does. So, Yeah, the same thing happened to me, but mine was a bit more obvious because I grew up in the North of England and studied in Scotland and kind of hung around the North of England for the first twenty odd years of my life. And then moved to the south where which is verdant and green and grassy, and immediately got terrible hay fever. Yeah, which I now know is an allergy to rye grass. What it will be for me too. There's a lot of rye grass out here. Yeah. So I haven't had it. I haven't been tested, but I I'm making that assumption. Also allergic to cats. There you go, grew up with a cat, never had a problem. Now I can't, you know, I can no longer rub my face in there, for which is so disappointing, So disappointing. Let's try rubbing your face in muscats fur it te your eyes out. Yeah, that's the other problem. That is the other problem that may explain the itchy. Now let's get down to business. This story is interesting because it really changes the way we're looking at one particular piece of space. And it's an area where we thought there was an intermediate mass black hole? Was it? Now they think it's not. It's not a black hole. It's a multi faceted number of black holes in possibly the tens of thousands. This is quite extraordinary. It is it's a story that I mean, we've been following the intermediate mass black called story for quite some time, and just to fill in the details for anybody new to the issue, we find we commonly find what we call stellar mass black holes, black holes with the massive you know, up to twenty stars, up to twenty sons, and we commonly find super massive black holes, which are sometimes twenty billion times the mass of the song. But there doesn't seem to be anything in between. The intermediate mass black holes have been elusive, and one place we think we might find them is in the center of these really spectacular gigantic star clusters that we call globular clusters because they're globular in shape. That name was given to them by William Hershall a couple hundred years ago or more. And we have by we, I mean the world of astronomy has basically been hunting for intermediate black holes in the centers of some globular clusters, and with sort of varying degrees of success in the sense that some of these findings are more certain than others. But one that we covered recently was a finding that yeah, we were pretty sure about for a while, and that is the globular cluster Omiga centaury it's the biggest of them. Our Milky Way Galaxi's retinue of globular clusters one hundred and sixty or two hundred of them, and this one is the biggest of them. Distance of seventeen thousand light years as the crow flies in the constellation of Centaurus, which is why it's called Umiga Centaury, and visible just about to the naked eye. In fact, it's this time of the year where we start seeing it quite well from here in the southern hemisphere. It's a deep south object invisible from the southern hemisphere. So what's the story. Well, scientists, in fact European scientists who were using i think something like twenty years worth of images from the Hubble Space telescope which allowed them to plot the motions of stars within Omega Centaury, and in particular they let them map the motions of stars near its center, which seem to have quite high velocities and which are symptomatic of something massive around which they're orbiting. So you've got stars with high velocities. In particular, the kind of velocities that were being talked about. I think they're in the region of three four, five, six kilometers per second thereabouts, if I remember rightly, those velocities. If there wasn't something massive of the middle would be enough to catapult them out of the globular cluster and they belong gone, they'd be interstellar, you know, the interstellar stars if I put it that way, stars between the stars, but more there will be within the halo of our galaxy, which is where the globular clusters lie, the halo being that sort of spherical shell of all stars and globular clusters. So that was the story as we reported it. The evidence that there's possibly something like a twenty thousand solar mass black hole the middle of Omega centaury. Yeah, and we were really. Excited by that because I think we'd only just sort of concluded that there aren't any and then we've found one. Yes, that's right, And then now we haven't. We've unfound it. We've an't found it because another group of scientists, using similar data I think they've basically analyzed the same data set, have suggested that the motions of the stars do not tie down that central mass as being a single object. They're what they're saying is that it's like it could equally and that's perhaps the best way to phrase it. It could equally be a large cluster of much smaller objects. It's there's still black holes because you can't see anything of them. There's no there's nothing massive visible there in any of the wavelengths. But we can tell by the motions of the stars that there is something there. And so what they are suggesting is that it's not a single lots a single intermediate black intermediate mass black hole. It's not that it is more likely or as likely, if I can put it that way, to be something between ten or twenty thousand stellar mass black holes. In other words, the smaller variety, right, And you know, that's the bottom line. And the group that's suggesting this, one of the team members of Francesca Calori from the French National Center for Scientific Research, says, the possibility of an intermediate mass black hole in Obena Centaury still exists. Our analysis does not rule out an intermediate mass black hole, but rather sets a limit on its mass, predicting an upper limit of six thousand solar masses, which is less than what the earlier team estimated. And so they, yes, they're trying to work out what that discrepancy is but yes, the you know that the later paper, the new research Calori etel. Is saying it might not be a single object. It could be you know, lots of lots of smaller objects. Yeah, and that's been backed up by another gentleman at Leiden Observatory I think, who agrees, even though he wasn't part of the study, agrees it's probably a multitude of stellar mass black holes rather than an intermediate mess black hole. That's correct. And actually there's an old friend of mine who was also commenting on this, Jerry Gilmore, who I've known now for forty years. He's a very big name in the University of Cambridge. He is a key. We actually came to the UK to work at the Role Observatory in Edinburgh, where I was working. We became good friends and still are. Jerry, he wasn't involved with the study either, and he thinks that stellar mass black holes are likely to be common in comparison with intermediate mass black call. So I think he's a favor. He's favoring the idea that the latest research, the idea that this is perhaps a whole lot of smaller black holes rather than one big one, and as you say, there's there's comments from Leiden Observatory Simon Porte Year's art if I'm pronouncing. That right, you know you did better than I would have. Finds the potential discovery of an intermediate blass glass black hole super exciting, but suggests that the evidence isn't quite there yet. So I think the opinion of the astronomical community is let's wait and see what future measurements bring out. It doesn't look as though we've nailed down the Omiga centaury intermediate black mass black hole yet, and it may not be there at all. That's it though. How unusual is it to find between ten and twenty thousand stellar mass black holes in a globular cluster. Yeah, that in itself I think is interesting. If you could, you know, if you could independently verify that these are singular objects rather than one big object, I think you have another new discovery on your hands. So what you're talking about here is going to be the remnants of dead stars, And what you're talking about with an intermediate mass black hole is the remnant of what might have become a super massive black hole if that globular cluster had not been torn to shreds by getting mixed up with our Milky Way galaxy the gravitational pull. Because we think the globular clusters are the central nuclears of galaxies that have been basically demolished by gravitational interaction with our own. And so that's why people are looking for intermediate mass black holes inside globular clusters. Because the thinking is, if you've got something that you know, under normal circumstances would eventually grow into a super massive black hole by the time the universe is thirty point eight billion years old, which is its current age, if you have that structure, but then you stop the evolution process because you tear the galaxy to pieces because it interacts, it gets basically sucked into the Milky Way galaxy. What you're going to be left is is something you know, it's like a wanna be supermassive black hole, which is why it's a good place to look for intermediate mass black holes, ones that didn't quite make it. So if it turns out it's not an intermediate mess black hole, does that mean we still haven't found any or were there are other candidates? There are other candidates. As I recall, I would like to pin down without looking them up as to what they are. But there are other candidates, so it isn't just this one, but this one, you know, Omega Centauri is the biggest and most spectacular lobby of the cluster in the sky. As I said, it's visible to the naked eye. It looks terrific. Even with a pair of binoculars. It looks good. You can tell it's something different from the stars around it. Through a larger telescope, it looks sensational because you can see all the individual stars resolved in it. This is a new problem, Fred, what's that? Well, if it is. Stellamass black holes they've found, and there are ten to twenty thousand of them, which is what they're suggesting, the world will have to come up with a collective noun for black holes because there isn't one. It will, ah, right, there isn't one. Surprised, Yeah, I was too, But I've found a couple of articles which state, no, there isn't. There's a collective noun for asteroids, it's a belt of asteroids, which, yeah, it's a good one, but there is no collective noun that I'm. Aware of for black holes. Maybe a space, not of black holes like that. Yeah, I was going to say nothingness. Yes, there isn't. There isn't nothingness. There isn't. It's a little bit of a problem, but it's not the biggest problem with fights. But yeah, I was surprised there wasn't one. Me too, Yeah, IM surprised. Also. Anyway, the jury is still out. Could be one, could be the others. We're not sure. We're not sure yet. But if you want to read up on that, it's a great article in Sky and Telescope dot org. This is Space Nuts Andrew Dunkley with Professor Fred. What's a. Okay? We take all forces of being with. Their Space Nuts now Fred to the Polaris Dawn mission. And this is a very exciting mission. It may well have lifted off since the release of this particular podcast, because we're working a bit ahead at the moment, because I've got to take a trip and we need to get a whole bunch of episodes in the can. So they say so, yes, this particular mission may well have lifted up at the moment. As we speak. They have some technical issues and they're stuck on the ground and they're all getting pretty tired of scrabble, but could be monopoly, could be monopoly, could just be who know who knows or drafts. Yes, oh gosh, getting desperate. But this is an exciting mission for several reasons. There'll be some major firsts that will be achieved. And yeah, they're doing things a little bit differently, and they're planning a space walk, which will be the first private space walk I believe, privately conducted. There's so much that it's exciting about this mission, Fred. Yeah, there is, and you're right. It's partly technical issues, partly the weather in fact that's been holding them up the splash down, So yes, exactly, it's not so much about. Getting off but getting back on the planet. Indeed, what's exciting about it, Well, it is going to be. It may even be the first crude mission that is going into a polar orbit around the Earth. Wow. I think that is correct. So it's an orbital direction that hasn't been explored before with crewed space launches. It's also not going anywhere. It is not going to the International Space Station, as you wouldn't be able to if you were in a port polar orbit because you need an orbit very similar to the International Space Station if that's where you're going. And that means that the time that the crew will be on board, and I'm actually not sure how long it is planned to be, but they are that they're going to be in the spacecraft for the whole time, except when they make the first privately operated extra vehicular activity, because what they have to do then is climb out of the SpaceX crew Dragon capsule. Two of the members of the crew. There are before people in the crew of Polarist Polarist doorm two of each gender, and they will two of them will climb out of the capsule for the first private space walk. And what that means is you've got to let this. You've got to let space into your capsule. You've got to vent all the air out of it. So everybody has to wear their spacesuit. Super scary. It's super scary opening the front door because they have airlocks in other spacecraft and the International Space Station. This one, you open the lid and space. You're in space before you even get out. Yes, that's right. So you've got to vent, haveaven you and then space it first. And then I mean, I'm sure there will be a very you know, it will be a pretty. Careful venting, just to make sure everything's solding together before you let all the air out. Yeah, it's not like the fish tank, that's. For sure, although if you find fish floating around it, you might be anyway. It's yes, So it really is interesting. And the fact that they're not visiting this space station or going anywhere near it means they have to be pretty secure in their plans for this mission because all the supplies for the crew, food, water, oxygen, everything that all has to ride with them in their crew dragon capsule. And so it's a very very demanding, you know, highly demanding scenario. It's five days the mission. Just too Yes, add to what I was saying, I just looked at up myself. And the other thing that they'll do is they'll go further from Earth than any human since Apollo seventeen back in nineteen ten, because their orbits is very elliptical. It's you know, an elongated orbit which will be close to Earth and it's Perry g the closest point, but a long way off at Apergee. I am not sure what the target Apogee is, but it is more than we've ever done before in terms of you know, a mission of this kind. So what's holding it up? Well, as I mentioned earlier, the weather, and as you said, yes, it's the weather at the landing site, but also the fact that within the last forty eight hours, certainly if not twenty four hours as we are recording, Falcon nine has been grounded. The Falcon nine launch vehicle that will they will use has been grounded by the Federal Aviation Authority due to a failed booster landing attempt, I think on Wednesday this past week. So it's you know, this is basically a risk minimization procedure. As soon as anything goes wrong that booster, the Falcon nine, the whole Falcon nine fleet is grounded until you know what the problem was. Yeah, I think one of the interesting things I think I read a little while ago that booster that failed. I think it was its twenty third mission, so it'd been used twenty three times. Now, originally they said they'd only reused them ten times, then it went to twenty times. Suspect now it's aimed at thirty times, but maybe twenty three is as far as it goes. Yeah, we'll stop at fifteen, just to be safe, by the sad that's right. Yeah, certainly if it was a human space flight, I think you would want to make sure that you were using a pretty new, pretty new booster orcket to get you up there. Indeed, and I believed, I'll be doing about forty experiments you might have already said that, which will all test everything from human spaceflight research to micro gravity. Uh. And I'll be using brand new space. Suits to do the spacewalk and do and they'll be I guess they'll be testing those, and let's hope they go, oh, hang on, this thing doesn't. Work before they've been the spacecraft. I'll be taking that back to Low's. Ye. Sorry for your overseas listeners, that's a mental store so that you know, automatically becomes sexist because half the crew is female. Sorry about that. Keep on keep on digging, Andrew, You'll be Yeah, I can't see I can't see out of the hole anymore. It's a black hole, very deep one. It's a stellar mass black hole. Stellar mass black hole. That's right at the moment, fast approaching intermediate mass. Yes. Also that swear that. That's where it is right below me and above me and around me. Yeah, but let's hope all goes well, and by the time people hear this, they're up and around the planet in an elongated polar orbit and doing some wonderful work. We'll see how it all transpires. Fingers crossed. This is the Space and That's Podcast with Andrew Dunkley and Professor Fred Watson. Broad Piacemuts. Now Fred to our final story, and this one takes us a long, long way out of the Solar System. This is our story. We've been following well since it's exciting flyby of Pluto. It's the New Horizons spacecraft. But since it successfully executed its primary mission, it's been sent off to do a few other things, and one of those things was to examine darkness. This sounds this sounds sinister, This sounds like the plot of horror movie. But it's not. It's a very interesting question which they think they might have answered. Yes, that's right, and I think you and I have been talking about New Horizons since its launch eighteen years ago because we used to talk on ABC Radio, didn't we did? All the Space That's program came into being, So New Horizons, yes, fly by Pluto in was it July I think twenty fifteen? Fly by our It used to be called Ultimate Tully, and it's now called Arakoth, a small kayper belt object which it flew by probably about three or four years ago. Now it's quite a while ago. In fact, it's longer than that, because the fly by was at Christmas and this object looked like a snowman until we realized it's actually two pancakes joined together rather than two balls joined together. Anyway, it is now seven point three billion kilometers from Earth, a long way away, not as far as our old friend Voyager one, but still still a long way out. The difference though, between New Horizons and Voyager one is that New Horizons has telescopes on board. Yeah, of course we used to scan Pluto and care on Pluto's main moon and some of the other moons as well. But what they've been able to do, though, is to make measurements of the blackness of the night sky. And hear you saying, wait a minute, black is black? Well, it's not really, and why should you want to do that from seven point three billion kilometers away from Earth. The answer is that the Solar system is very dusty, and that dust concentrates towards the center of the Solar system, so you know what we see as meteors. Shooting stars are a measure of the dust that is around us in the vicinity. That dust scatters light, and we can actually see that in the form of the what's called the zodiacal light, which is a glow on the horizon eastern and western horizon after sunset and before sunrise. What you're seeing there is light scattered from dust in the inner Solar system. It's an olor of light quite spectacularly. You need a dark sky to see it. I've seen it many times from our dark sky sights here in Australia, but I only ever saw it once in the UK, and that was in a particularly dark part of the UK. It was quite see a long time ago as well. Anyway, So the Inner Solar system is very dusty. That dust scatters light, and that means that if you want to make a measurement of just how bright, how intrinsically bright, the night sky is, you've got to get away from the inner Solar system, and that's where New Horizons is. So what they've done is they've measured what they're calling the cosmic optic called background. We talk a lot on space Nuts about the cosmic microwave background radiation, and this is the background to the night sky in microwaves, which we recognize as having been caused by the Big Bank. We're still seeing the flash of the Big Bang. The cosmic optical background, though, is basically a background haze of light that comes from all the galaxies that have ever existed over the lifetime of the universe. Wow. And so this light is the light of galaxies. Turns out to be just the right brightness. I mean, it's been measured. The blackness of the night sky has been measured by New Horizons. The answer they get is exactly what you predict from what we assume is the known number of galaxies in the universe, which is in the region of two trillion if I remember ran So really quite a nice piece of work complemented on by New Horizons principal investigator Alan Stern and an no friend of this program. He says, this newly published work is an important contribution to fundamental cosmology and really something that could only be done with the far away spacecraft like New Horizons. And it shows that our current extended mission is making important scientific contributions far beyond the original intent of this planetary mission designed to make the first close spacecraft explorations of Pluto and Copper Belt objects. So there you go. It's got the impromato of the Boss of New Horizons, Alan Stern. And it's a really interesting result that, you know, the amount of light in the universe adds up with the number of galaxies that we think it. And yet and yet we shouldn't be surprised because where else could the light have come from? Well that's right, except that the one of the scientists who's involved with this work has basically raised that question, could it come from something we haven't thought of yet? And so the fact that it it, you know, everything adds up suggests that there isn't anything that we haven't thought of yet, although you can bet your life that one day we'll be surprised that there's something else going on. But yeah, you know, it's at the moment we think these that these all add up the amount of light that's exactly what you'd expect from the number of galaxies we assume the universe contains from galaxy counts. In fact, I know one source they haven't considered the laser beams shooting from my wife's eyes. When she is angry with me. That's that's one light source that hasn't been factored in. You're dead keen on getting into halls today. I'm not going to go there at all, I think. No, I wish I hadn't. That pretty exciting stuff for new Horizons will continue on its journey doing more scientific studies, imaging the Kuiper Belt and the outer heliosphere and making observations from a vantage point that. No, it's unique. It's the only spacecraft in the position to be able to do anything like this. Even James Webb and Hubble can't do the kinds of things that you Horizons is achieving. So that's, uh, we'll be talking about again, I think, Fred. Yeah, sure, it might. Take a while, has still got a long way to go. Yes, that's right. It's it's one of the five space craft leaving the Solar System. Yeah, but I think it's the best equipped to do to make observations like this. Indeed, all right, that story available at fizz dot org phy s dot org if you want to check it all out. And that brings us to the end of the show. Just a reminder too, if you would like to visit our website, you can do that at Space Nuts podcast dot com or space space Nuts dot io. You can visit the shop or you can send us questions. You can get the daily news feed through Astronomy Daily. You can even support us through the support space Nuts button. Here you are and yeah, there's all sorts of things to see and do on our page Space nuts podcast dot com or spacenuts dot io. And if you're a. Social media follower and you watch or listen to us on YouTube, don't forget to hit the subscribe button down below. Thank you as always, Fred, it's been a great pleasure. Yes, it's been a pleasure for me too. And that's long long mate, continue. Not many people say that to me. Thank you, especially today. Thank you Fred, don't worries see you soon, see yea Professor Fred Wartson, a storm at large. And thanks to Hue in the studio and from me Andrew Dunkley, thanks for your company. We'll catch you soon on another episode of Space Nuts. Bye bye. You'll be listening to the Space Nuts podcast available at Apple Podcasts, Spotify, iHeart Radio, or your favorite podcast player. You can also stream on demand at bytes dot com. This has been another quality podcast production from Nights dot com