JWST has turned the Crisis in Cosmology into a bigger problem | Night Sky News August 2024

hello and welcome to this episode of Night Sky News for August 2024 with me astrophysicist DrBecky smithurst this is the show where we talk about what you should look out for in the night sky in the next few weeks and then we talk about what's been happening in space news in the past few weeks in this episode we've got to chat about J's long awaited look at the crisis in cosmology which it turns out it hasn't solved like we thought earlier this year and chat about this new evidence for water reservoirs under the surface of Mars so this episode is jock full of science there's chapter markers down here if you want to skip ahead to any specific new story plus any scientific research papers I mention are all going to be linked in the video description down below free to read so without any further Ado let's kick things off and start by looking up all right let's start with the planets because there are six visible at the end of August and early September Mercury down closest to the horizon then Jupiter and Mars all visible in the morning sky with Uranus and Neptune close by for those with telescopes or binoculars to try and spot and then you've got Saturn which will be visible all night rising to its highest around about midnight Saturn will appear yellowish and if you look roughly to the South you should be able to spot it remembering that planets don't twinkle in the same way as stars do so that's usually how you can figure it out but if you can't don't worry grab a star chart at that you can like grab your phone and sort of like point it in the right direction and check that that's what you're looking at as spot in Jupiter and Mars in the Earth early morning Sky you've once again got a cresant moon AKA my favorite moon phase a toenail Moon pairing up with them to help guide the way from Monday the 26th to Wednesday the 28th of August so on the 26th the moon will be just above both Jupiter and Mars right next to the plyy star cluster making a great SI astr photographers and those again with telescopes and binoculars at home then by the 27th the moon will be closest to the very bright Jupiter then on the 28th closest to the reddish fainter Mars and if you've got a very clear look at the Eastern Horizon I'm talking absolutely nothing in the way like looking over the sea for example then you might be able to spot the tiny sliver of a moon next to the very faint mercury in the glow of sunrise on Sunday the 1st of September and if you do manage to spot any of this whether it's Mercury or Jupiter or Mars then notice how close this all is to the constellation of Orion it's now visible in the morning sky and Orion appearing again in our skies can mean only one thing to a northern hemisphere astronomer winter is coming now by Sunday the 8th of September Saturn will have reached what's known as opposition when it's in the exact opposite part of the sky from the sun it's like you've essentially drawn a line between the sun Earth and Saturn so this is why it's visible all night Rising as the sun sets and then setting as the sun rises it also means that Saturn is like perfectly lit by the sun right now so it's the brightest it ever gets in our skies which means it's just a really nice thing to look look out for as we get into September drawing ever closer to the Equinox of equal night and equal day lens it means wherever you are in the world there's you know a good amount of nighttime to be able to try and spot this then on Wednesday the 18th of September we once again get treated to another Super Moon where the full moon is the closest it can get to Earth around about 40,000 km closer to us and it's slightly over shaped orbit meaning the full moon will technically be larger and brighter in the sky however these differences are very slight it's around about 30% bigger than a micro moon when it's at its furthest point away from us in its orbit and about 14% bigger but because you don't have a normal moon or a micro moon to directly compare it to like in the graphic I just showed you can't really pick out the differences in the size and the brightness with just your eyes if you're seeing the super moon on that night and you think whoa it looks so much bigger and brighter than it does normally I'm guessing what you're actually seeing is the Moon Illusion when the moon is much lower down towards the horizon and you're comparing it to everyday objects like trees and buildings and it only appears larger when in reality it's actually just the same size as always it's an illusion I think the only people who really tend to notice super moons are people in really dark skies so very rural areas when the moon is very bright and you can get a really clear distinct Moon Shadow that is if you're not in the path of the partial lunar eclipse that is also happening on the night of the 18th of September where the moon will fully pass into the Earth's outer Shadow but only just Grays that much darker inner Shadow which can turn the moon orange so if you're in Western Europe western Africa the east coast of the US and Canada or anywhere in South America then you should be able to see this fully I'll pop a link in the description down below so you can put your location in and work out what you'll be able to see and also at what time basically if you're in the right place then you should be able to spot that the Moon looks slightly darker than normal and that there is also sort of a slight Nick taken out of it at the top which is the Earth's inner Shadow that's cast on it and notice how that shadow is sort of the wrong way around for how sort of like the shadow on the moon usually progresses just as it moves through its phases which I think is why it's so good fun to spot right because it's just a nice reminder that everything's just wearing away up above our heads up there now if you're struggling to visualize all the movements of the planets and the moon and how it ties into what we can see in the sky that's totally understandable it's this big 3D thing that's just wearing away with all these moving parts and it's hard to visualize in your head now if that's the case I've got something that I think might help so before we chat about what's been happening in space news let me tell you about the sponsor of today's video brilliant brilliant is where you learn by doing with thousands of interactive lessons in science maths data analysis programming and AI it's a learning platform that's designed to be uniquely effective with their first principles approach to each new topic that helps you build understanding from the ground up each lesson is filled with Hands-On problem solving that let you like play around with a concept a method that's been shown to be six times more effective than just passive learning like watching videos or lectures course all the content on brilliant is crafted by an award-winning team of teachers researchers and professionals from places like MIT ctech Duke Microsoft Google and more I absolutely love their scientific thinking course which introduces you to key scientific principles and theories from simple machines like gears and pulley to Einstein's theory of special relativity it'll help build your natural intuition for science while also gaining this this deeper knowledge of scientific principles plus it's perfect for Learners of every level because there's no complex maths needed so to try everything that brilliant has to offer for free for 30 days visit brilliant. org Becky or click on the link in the description below and you'll also get 20% off brilliant's annual premium subscription so thank you so much again to brilliant for sponsoring this video and supporting this Channel and now let's come back down to earth and chat about what's been happening in space news in the past month now the first thing that we have to mention is that NASA astronauts Sunni Williams and Butch Wilmore are still stuck the International Space Station they arrived on a Boeing Starliner on the 6th of June on its first crude test flight but during the flight they reported problems with five thrusters and five helium leaks during either the launch or the docking of the craft to the space station so they were originally only supposed to be there for this very first crude test flight of Boeing Starliner for 8 days and they have now been there for over two months all the while back on the ground there's been these ongoing tests and Analysis to try and work out if it's actually safe for them to travel back to Earth on board the Starliner now as of the day that I'm filming which is Thursday the 15th of August NASA haven't yet made a call on whether they're going to do that or not or when the astronauts will even come back the decision is expected by the end of August and from what we're hearing it sounds like Boeing is convinced that Starliner is safe and they'll be able to come home just fine but NASA are being extra cautious probably given their history of space fight disasters with astronauts in the past in the meantime NASA do have a plan B already and that's that they'll come home on a SpaceX crew dragon mission that's launching four astronauts to the ISS in September but won't be returning until February 2025 meaning that those two astronauts that went to space for 8 days will instead spend 8 months in space now that does bring additional risks because the space suits that were developed for the Boeing Starliner can't be worn in the SpaceX crew Drgon which means they'd have to do that return flight space suitless which also comes with all of its risks as well so NASA decision makers are basically just going to be weighing up the risk of you know taking the Boeing styliner back to Earth or waiting eight months and coming back in the grw dragon and then also the mental toll that this is going to be having on the astronauts as well back on the ground though and the Vera ruin observatory's secondary mirror was installed this month in early August as part of its construction in the Chilean desert now if you've not heard that term before of secondary mirror let me explain in a telescope you have the main primary mirror that collects the light from objects in space and the bigger the mirror you have the more light that you can collect so the fainter the object you can see and also the bigger miror you have the smaller the object that you can resolve on the sky and Reuben's primary mirror is 8. 4 M wide now the secondary mirror's job is to then redirect that light and focus it down to the detector the camera that's recording what the telescope sees now at 3.

5 m in diameter Ruben's secondary mirror is actually one of the largest convex mirrors that has ever been made for context it's larger than the Hubble Space telescope's primary mirror which is is 2. 5 M across now most telescopes do just have the two mirrors primary and secondary but Reuben has three mirrors to help Focus the light down and this is what gives it it's like collecting power and flexibility that allows it to complete its huge survey of the sky that's planned if you want to know more about the reuin observatory and what its goals are check out the video I made earlier this month about it I'll link it in the video description down below now onwards to Mars because this research paper was released this month from right collaborators using data from NASA's Insight Lander to claim that there are water reservoirs deep under the surface of Mars I was so excited when I saw this research paper and I feel like the in joke between me and all my colleagues is like oh we were all searching for water on Mars all of these years and we should have been searching for water in Mars so as a reminder NASA's Insight Lander landed on Mars back in November 2018 equipped with a seismometer to detect Mars qu like earthquakes where the ground shakes but on Mars over its four years of operations Insight detected over 1,300 Mars Quakes before the mission ended in December 2022 when the solar panels just became too thickly covered in the Martian dust to provide the Lander with any power anymore but with all those detections the team managed to figure out the interior structure of Mars so the depth of its crust its mantle and its core so what writing collaborators have now done is modeled the Daya with a few different parameters including the liquid water saturation which is shown by the parameter gamma W there which you can see in their best fit most likely model has a value of 100% I it's just water at least for the rocks in the mid cross area that they've been studying here which are around about 11 to 20 km under the Martian surface so they're claiming that there is a huge reservoir of water deep under the surface of Mars which is huge if true because it has so many implications for the history of Mars and the age old question of where did all the water go because we know that Mars has polar ice caps so solid water at the poles and then we see all of this geological evidence in Martian rocks for liquid water once flowing on Mars's surface billions of years ago so where did it all go one thought is that as Mars slowly lost its atmosphere over billions of years because it got bombarded by high energy particles from the Sun that stripped it all away that the water evaporated and was lost to space but with the discovery of these huge reservoirs then that doesn't have to have happened and then there's the even bigger implications this has for the possibility of Life on Mars because if you've got water deep underground and you've got heat from the planet's interior you've got the ingredients there for life life might be able to thrive there life like what we find here on Earth by warm ocean sea vents kilometers down where it's usually pitch black you know if you'd asked me like two weeks ago about the potential for Life on Mars I would have said okay well you know like maybe NASA's perseverance Rover might find evidence of past life on Mars but this new result from wron collaborators makes the possibility of Life currently existing on Mars just that little bit more plausible cuz you know as Jurassic Park taught us life uh finds a way but finally onto the news we have all been waiting for J bis's look at the crisis in cosmology aka the Hubble tension now if you've been following me for a while now you will be no stranger to this problem and if you remember back in April last year I reported on how one of my colleagues Wendy Freedman who leads one of the teams using jst to look at this problem had presented some of team's early results on the conference circuit back in Spring but all we had to go on were her slides and her talk we didn't have a research paper with all the detail yet but now we do after this research paper from the research group appeared online in mid August it's still not gone through peer review it's just a pre-print after all but it's still more detailed than we had before so before I get ahead of myself I'm going to attempt to do what is hopefully a quick recap of the Hub tension if youve heard me say all this before you can skip ahead to this Tim stamp now basically we have a few different ways of measuring the current rate of expansion of the universe what's known as the Hubble constant now that name is a misnomer the expansion rate of the universe is not constant it is changing with time and there are other projects measuring that that I've covered before on this channel but when we refer to the Hubble constant we're talking about the rate of expansion that is currently happening now now there are two main ways that we can measure this firstly we measure both the distance to nearby galaxies and then the velocity that they appear to be moving away from us because the universe is expanding and we plot one against the other and the slope of this line is the current expansion rate the Hubble constant H KN and we do that we get a value of around about 74 km/s per MEAP par now the other way that we can do this is to just model the entire universe starting with the earliest light from when the universe was just 380,000 years old what's known as The Cosmic microwave background and then we come up with a model that contains All the known laws of physics and all the known components of the universe mix it all together and you try and get from the cosmic microwave background to the universe that we see today we then find the best fit model to the universe that we see around us and from that we can determine many different properties and parameters of the universe like the current rate of expansion hn when we do that we get a value of around 67 km/s per megap Parc so a value of 67 on one hand and a value of 73 on the other but these two methods didn't always disagree they started out agreeing on the estimated value back when the errors on the measurement were quite large but as telescopes and Analysis techniques got better the estimated errors reduced and the values returned by each method started to drift apart until they completely disagreed with each other statistically speaking there's only around a one in a million chance that the reason these two methods don't agree with with each other is because of a statistical fluke which got a lot of people concerned for obvious reasons and there's two main camps emerge to try and explain what is going on either there's something wrong with our observations of nearby galaxies perhaps how we're calculating their distances or there's something wrong with our best model of the universe maybe we're missing a LW of physics or maybe there's a component of the universe that we don't know about yet now along with those two camps there's also two big research teams that fall into one of those two camps as well one is led by Adam Reese at John's Hopkins who's already shared the Nobel Prize in physics in 2011 for showing that the Universe expansion rate was accelerating with time and the other is led by Wendy fredman at the University of Chicago who heads up the Chicago Cari Hubble program to measure this now both research groups have got time on jwst to once again measure the distances to nearby galaxies and see if they change now we've got better data with jwst compared to what we had with Hubble now we've already heard multiple times from Adam Reese's group that they don't think it's the first option they don't think there's a problem with the distances to nearby galaxies that we're calculating and we do this using something known as The Cosmic distance ladder now the first step on the ladder is to get distances to stars in our own galaxy The Milky Way using some something known as Parallax then the next step is to work out the distance to nearby galaxies where we can make out individual Stars known as standard candles well we know how bright they should be because we've observed them in our own Milky Way and we know from Parallax how far away they are so from how bright they appear in other galaxies we can work out okay well how far away are those galaxies now there's a couple of different standard candles that you can use the most famous being using seid variables St stars that pulse in proportion to their maximum brightness they can reach but there's other types of stars that we can do this with as well those at the tip of the red giant Branch or the J region asymptotic giant Branch Stars which again have a known brightness in the Milky Way where we already know their distance from Parallax now we can't use these measurements of distances to nearby galaxies to work out the current rate of expansion of the universe because they're too nearby right their movements are affected more by the gravitational pole between them than they are by the expansion of the universe instead you have to go another step up the cosmic distance ladder we need the distances to even more distant galaxies which are too far away for us to make our individual Stars they're just too faint to pick out that is until one of them goes Supernova and gets incredibly bright and is also a standard candle so as long as you have a Galaxy that at some point has both you know a supernova and a seid or a supernova and a trgb or supernova and a chb star in it then you can use that Galaxy to essentially calibrate all these steps along the cosmic distance ladder and then you can measure the rate of expansion of the universe which again is the value that doesn't match with the value we get from our best model of the universe and so this is why a lot of people think that you know the problem that's causing the Hubble tension is something to do with our distances to galaxies because this Cosmic distance ladder is just one big house of cars that is to come tumbling down so I think the main idea that everyone has been focused on is that this middle rung of the cosmic distance ladder using these individual stars to get at distances to galaxies was affected by what's known as crowding the hobble Space Telescope essentially couldn't separate the individual stars out because it didn't have a high enough resolution so the individual brightnesses of the stars that you measure were affected by the Stars nearby so the brightness wasn't very accurate and therefore the distance that you got out wasn't accurate either but with j w t being so much larger than the Space Telescope it can resolve smaller things and resolve the individual Stars so much better giving you a better calibration for those distances that's then propagated up that Cosmic distance ladder to the next step with the Supernova and even more distant galaxies but this is what Adam Reese's group known as shoes has already looked at with Jade R A few times now with youan and collaborators in 2022 claiming that you measur the same brightness for seid variables with J brisy as you do with the Hubble Space Telescope in the single Galaxy that they'd been obs OB served in at the time which meant there was no change in the distance you measure which meant there was no change in the Hubble constant that you were going to get out either then in early 2024 we saw this research paper led by Reese using data from five galaxies observed by jst claiming it definitely wasn't the crowding problem with the seids and again that the distances to galaxies you find with jst and the hobble Space Telescope were the same similarly this paper by Anand and clator showing the distances you calculate with the seids and the trgb stars were the same and similarly this paper from Leon collaborator showing the distances you calculate with the seids and the JB Stars was the same basically that research group are pretty sure that at least with the data they have so far that it's not option one and instead they've got evidence that new physics is needed in our model of the universe so with all of that background info what then did the other research group that's looking at this find this Chicago carigi Hubble program that's led by when freed well they've now used 10 Galaxies that have been observed with jdst which all have Supernova in them and seids and tjb stars and tagb stars and they've recalculated the expansion rate of the universe and note that they originally intended to do all of this analysis blinded right which is where you know you're you're working with the data that you have but your analysis program puts in like random noise that you don't see the exact values that you can't be biased by the values that you're getting out and when Freeman presented these preliminary results in April it was just after they'd unblinded their results back in March and back then they claimed an average value of the rate of expansion the Hubble constant taken across all three of these different standard candles of 69. 1 plus orus 1.

3 km/s per megap Parc a value that was not statistically different enough from our value that we get from our best model of the universe around about 67 to believe that even was a Hubble tension back in April they were claiming that the problem had just gone away entirely but then they found there was actually an issue in one of the steps of the analysis that they done in their blinded analysis with the seid variables a necessary correction have been made to the seids twice in some cases so they had to recalculate the rate of expansion they found for the seph variables and then also the average rate of expansion they found overall across the three different standard candle methods and their value for the rate of the expansion the Hubble constant went up again so using the seid variables as that standard candle to calibrate the middle wrong of the cosmic distance ladder they get a value of 72. 5 km per second per MEAP Parc for the rate of expansion using trgb Stars instead they get 69. 85 km/ second per MEAP Parc and using the JB Stars they get 67.

9 6 k /s per megap Parc giving an average value of 69.