Transcript

JWST spots a star BEFORE it goes supernova | Night Sky News October 2025

From Dr. Becky · Episode page · Watch on YouTube

· 22 min · 4,086 words · 27 timestamped sections

This is the full, timestamped transcript of "JWST spots a star BEFORE it goes supernova | Night Sky News October 2025", an episode of Dr. Becky published October 23, 2025 (22 min, about 4,086 words). It mentions 9 people, works and ideas, including JWST, ExoMars, Ground News, TD Cosmo collaboration, Hubble Space Telescope.

What is discussed, and when

  1. – 5:00: Dr. Becky Smith, ExoMars, Ground News
  2. – 10:00: ExoMars, Ground News
  3. – 15:00: Hubble Space Telescope, Kilpatrick, NGC 1637
  4. – 20:00: TD Cosmo collaboration, Einstein's theory of general relativity

Notable quotes from "JWST spots a star BEFORE it goes supernova | Night Sky News October 2025"

  • About what's been happening in space news in the past month. In this episode, we're chatting about ExoMars's view of the interstellar comet 3i Atlas. Plus, JWST spotted a…
    about ExoMars · at
  • With so much misinformation and clickbait out there. Well, that's where Ground News comes in. The sponsor I've been working with for over a year now.
    about Ground News · at
  • Has managed to spot a star before it went supernova with this research paper from Kilpatrick and collaborators. Now, this is a really big deal because the thing about supernova…
    about Kilpatrick · at
  • Stars are ready to go supernova, they become shrouded in dust. Dust the likes of which that the Hubble Space Telescope observing a universe in visible light that we see with…
    about Hubble Space Telescope · at
  • Supernova. Not [clears throat] only that, but there's even Hubble images of this galaxy, NGC 1637, that [clears throat] were taken way back in August and October 2001, which…
    about NGC 1637 · at
  • Lot more questions as well. And finally, I've been hearing a lot of buzz lately about the work from the TD Cosmo collaboration, who are trying to use something known as time…
    about TD Cosmo collaboration · at
  • Galaxy. This is what's known as gravitational lensing. So our best theory of gravity, Einstein's theory of general relativity says that the effects of gravity can be described…
    about Einstein's theory of general relativity · at

Who and what is mentioned in this episode?

People

  • Dr. Becky Smith — Person · 1 mention · first at
    Hello and welcome to this episode of Night Sky News for October 2025 with me, astrophysicist Dr. Becky Smith. This is the show where we chat about what you should look out for…
  • Kilpatrick — Person · 1 mention · first at

Companies & orgs

Concepts & topics

Full transcript with timestamps

Hello and welcome to this episode of Night Sky News for October 2025 with me, astrophysicist Dr. Becky Smith. This is the show where we chat about what you should look out for in the night sky in the next few weeks and then we chat about what's been happening in space news in the past month. In this episode, we're chatting about ExoMars's view of the interstellar comet 3i Atlas. Plus, JWST spotted a supernova before it went supernova and the latest on the crisis in cosmology with a new independent measure of the expansion rate of the universe. There's chapter markers down here if you want to skip ahead to any specific news story, plus any scientific research papers I mentioned will all 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, first up, we just saw the peak of the Orion's meteor shower a few days ago on the 21st of October. Now, I spoke about this in last month's Night Sky News episode. And yes, although most shooting stars in the shower can be seen on the night of the peak, there will still be meteors from the shower visible throughout the rest of October and into mid- November. So, keep your eyes peeled while you're out stargazing for any surprise shooting stars, as that's just going to be more common than normal. Now, on the night that this video goes live, so Thursday the 23rd and Friday the 24th, we have a cresant moon in the west just after sunset pairing up with Mercury and Mars very [clears throat] low in the sky. Now, you are going to need a very clear horizon for this with no trees or buildings in the way. And also, the further south you are, the higher they will rise above the horizon and therefore the easier this will be to

spot. Mercury is notoriously difficult to spot because it's always so low in the sky because it is the closest planet to the sun. But this at least gives you a signpost for where to look if you can find the moon first. Mercury will actually be at the highest it gets in the sky on the 29th of October as it reaches what's known as the greatest eastern elongation appearing the furthest away that it possibly can from the sun from our perspective. So if you can try and spot Mercury along with Mars that will still be in roughly the same part of the sky around about Halloween if you can. By the 1st and 2nd of November though the moon will have moved around the sky to pair up with the yellowish Saturn. It will be an almost full moon by that point and this will be visible in the evening skies. Then by the 10th, when the moon is just past full, it'll be pairing up with the much brighter Jupiter from midnight onwards

into the early morning. Again, just handly acting as a signpost for where to look for the planets this month. Then in the middle of all that, on the 5th of November on bonfire night, the moon will be full and once again class as a super moon where it's a full moon when it's closest to Earth in its ovalshaped orbit, making it appear brighter and bigger than normal, although not noticeably so to the human eye. The timing of this full super moon, though means that it will wash out the shooting stars from the torids meteor shower, sadly. So that means there's no need to make a special trip to see that one this year. However, by the 17th and 18th of November, the moon will be back to a cresant, meaning the sky will be nice and dark for the peak of the Leonid's meteor shower. The shooting stars from the shower are caused by tiny bits of rock burning up in the Earth's atmosphere that are debris left behind

by the passage of the comet Temple Tuttle. Now, the Leonids are particularly famous because of the meteor storms of over a thousand meteors per hour that it can cause every 33 years or so as we pass into fresh comet debris trails. The last of those was around the millennium. So, we're not due one just yet. Instead, this year the forecast is for around 15 meteors an hour. So, one every 4 minutes or so, which like a typical meteor shower. That is though in the very darkest of skies away from the bright lights of a city.

So if you're in a suburb, expect a bit less than that. The best time to watch for this though is the hours around midnight on the night of the 17th going into the morning of the 18th of November. Especially because if there is going to be a surprise outburst of more meteors, that is when it would be. But now it's time to turn our attention to the space news stories of the past month because there's been some big ones. Did you all see this one about how JWST spotted a rogue planet growing at a rate of 6 billion tons per second? When you see a headline with crazy numbers like that, how do you know what you're seeing is a legitimate story based on scientific research findings? Cuz let's face it, searching for news on the latest JUST discoveries is a minefield with so much misinformation and clickbait out there. Well, that's where Ground News comes in. The sponsor I've been working with for over a year now.

With ground news, I can see straight away that 105 different news sources covered this story with 96% of those sources having high factuality ratings. So with a few quick glances, I immediately know that this story is genuine. But then I can also easily compare headlines from different news stories. So I can see that nature went simply with rogue planet is fastest growing ever observed compared to express us's fear-mongering of astronomers warn of rogue planet growing at records shattering rate. It's datadriven tools like this from ground news that make understanding and staying informed with the news just so much easier. Like their blind spot feed for example which shows which stories had little to no reporting on either side of the political spectrum. So if you head to the link in the description down below at ground.news news/dbecky or scan the QR code on screen. You'll save 40% on their Vantage plan to get unlimited

access to all of their features, which comes out at around about $5 a month. Those subscriptions help keep Ground News ad free and therefore free of any bias that comes with paid advertising. So, a big thanks again to Ground News for continuing to support 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. All right, first up, if you remember last month's Night Sky News, we caught up with all things comet 3i Atlas, the interstellar comet that is visiting the solar system that was discovered back in July 2025. So, this is an asteroid or cometlike object. So, just a lump of rock that instead of orbiting the sun as part of our solar system is just passing through, right? It's formed around another star in our galaxy. It was then ejected from that orbit around that star and has been traveling through the space between stars interstellar space ever

since until it's happened upon the solar system. Now, there's been two of these found in the past. The first one I dubbed AmuA Mua was found in 2017 and the second two eye was dubbed Borisov and that was detected back in 2019. And we know these are interstellar objects because their movements through the sky allow us to work out their orbits and show that they're not bound to the sun. they don't loop back around again. So once we find these objects passing through the solar system, we can then study them to learn so much about, you know, what are they made of and other comet like things in our solar system made of similar things? How weird is the solar system? So of course all our telescopes have been set the task of observing comet 3i atlas in the past couple of months including the whole space telescope, Gemini, the very large telescope and also JWST like we spoke about last month. But on the 3rd of

October, 3IE Atlas passed just 30 million km away from Mars. That's around about 100 times the Earth Moon distance for context. And so the European Space Agency capitalized on this and used the satellites that they have in orbit around Mars. That's the Mars Express and also Exom Mars Trace Gas Orbiter to observe the comet as it passed by. Now, the instruments on board their satellites were specifically designed to image the very bright surface of Mars only a few hundreds of kilometers away. So, the teams weren't quite sure what they were going to get by pointing at a faint comet millions of kilometers away instead. But since they were the closest missions of the issa fleet to the comet at the time, it definitely made sense to try. So, this is what ExoMars saw. So, this is just a GIF of Comet 3i Atlas appearing as that slightly fuzzy white dot there that's moving diagonally downwards from right to left. Each image

in the GIF is just a 5-second exposure that the instrument on board Exom Mars took, which is the maximum limit for that instrument on board Exo Mars. And the fuzziness that you can see there is the comet's coma of gas and ice that's streaming off the comet as it warms up in the sun. The coma itself is around about a few thousands of kilometers across. So that's all really exoms can see. You can't see the nucleus, right? The actual central rock of the comet itself since that's only a few kilometers across, right? It's just too far away to see. Nor can you see like the full extent of the tail of the comet. The other telescopes have revealed as well as that also gets too faint and gets lost in the noise of the image. But really, it's amazing Exom Mars even saw anything at all because nothing's been found yet in the images that Mars Express took, which are limited to just a half a second exposure

because again, usually it's taking images of very bright objects on the surface of Mars instead. To put this into perspective, the PI of the instrument on board Exomar that took these images, Nick Thomas, was quoted saying that the comet is around 10,000 to 100,000 times fainter than their usual targets. So, because it's so faint, it's currently uncertain as to whether we've got any useful data from the other instruments on board ExoMars or Mars Express. The ones that like take a spectrum of light where you split the light through a prism into its rainbow to get a trace of how much light of each color or wavelength it is. Then you can use that data to work out, you know, what is the comet made of? Now, if that isn't successful, we've also got ISA's Juice mission set to observe comet 3i Atlas in November as well. Juice is currently on its journey out to Jupiter.

won't get there until about the 2030s. But it's equipped with a lot of instruments to study what the moons of Jupiter are made of. And so we can deploy those instruments to study three atlas as well. So once we know more about those observations, I'll update in a future night sky news as well. But now let's chat about some of the latest JDSt news because yes, it has been spoiling us again this month with incredible images. this time of the largest star forming region in the Milky Way, the Sagittarius B2 cloud, showing us the view when dust blocks some of the light from the newly formed stars and the view of the dust itself glowing. This is a really interesting region near the center of our galaxy to study because although it only has like 10% of the gas that's at the center of the Milky Way, it's forming 50% of the new stars towards the center. So, it's a really efficient star forming region and we

don't really know why it's so efficient. So, yeah, a very pretty picture for now, but hopefully leading to some interesting science in the future and some answers on this Sagittarius B2 cloud very soon as well. But in the meantime, this month we heard how JWT has managed to spot a star before it went supernova with this research paper from Kilpatrick and collaborators. Now, this is a really big deal because the thing about supernova is we don't know when they're going to happen. So, when a star runs out of the fuel that it needs to use in nuclear fusion to produce its light and its heat, it has no process left to fight the pull of gravity inwards and it starts to collapse. The outer layers of the star rebound off the core and get thrown outwards in a violent explosion we know as a supernova. And while we have some idea of roughly when stars are near the end of their life just from their

properties, we can't predict it with any accuracy because we just can't measure directly how much fuel a star actually has left. So supernova come as a surprise to us. Meaning that when we finally can observe them with our telescopes to study them, it's after the explosion. So then we have to play detective. be able to look back at old observations to see if we can first of all see a star where the supernova went off and then whether we even have any detailed observations of that star that can tell us anything about you know what kind of stars go supernova and specifically when they go supernova. But then the problem was most of the time when we looked back at our old data for the stars that used to be there before a supernova, we couldn't always see anything. And that suggested that when stars are ready to go supernova, they become shrouded in dust. Dust the likes of which that the Hubble Space Telescope

observing a universe in visible light that we see with our eyes can't actually see through. So the hope has always been that by using the James Web Space Telescope JB T which observes the sky in infrared light, we can actually see through the dust to see what was there before the supernova. So then it's just a waiting game for a supernova to go off in a galaxy that JBST had already observed in the past couple of years.

One eternity later. And finally, that's exactly what we got with the supernova SN 2025PHT, which went supernova back in July of 2025 and was first spotted by the All Sky Automated Survey for Supernovi, which uses 20 robotic telescopes all around the world to keep an eye on the sky for anything going bang. And thankfully, this supernova SN225PHT went off in the galaxy NGC1637 that had been observed before by both Hubble and JWST and then again after the supernova by the Hubble Space Telescope. And so what's really cool here is that you can see the supernova is really bright in the Hubble images from July 2025. But in the Hubble images from August 2024, you can't see a star where the supernova appeared, which they marked with the little red dot there.

Whereas in the JWST images taken before the supernova in October 2024, you can see that there was a star there. With JDSt, we can see through the dust to see what the star looked like before it went supernova. Not [clears throat] only that, but there's even Hubble images of this galaxy, NGC 1637, that [clears throat] were taken way back in August and October 2001, which show you actually used to be able to see a star there before it disappears behind its dusty shroud so that you can't see it in the August 2024 images again before it then goes supernova in July 2025 and we can see it again. So with these images, we can get a much better idea of the kinds of stars that go supernova, what environment they live in, and what stage in their red giant star evolution are they in. So we know now that this star was around about 15 times heavier than the sun when it went supernova. And it was in an environment

rich with carbon rather than silicon like initially expected for red giant stars. So this is a huge milestone for supernova studies, but it also raises a lot more questions as well. And finally, I've been hearing a lot of buzz lately about the work from the TD Cosmo collaboration, who are trying to use something known as time delay cosmography to crack a long-standing problem in astrophysics known colloquially as the crisis in cosmology, which longtime subscribers will know I have covered many times on my channel before. So, as a quick recap, the crisis in cosmology is the fact that we have a few different methods, but two main ones of measuring the current rate of expansion of the universe, what's known as the Hubble constant. And quite spectacularly, their measurements don't agree. The first main way we do this is to measure both the distance to nearby galaxies and the speed that they appear

to be moving away from us because of the expansion. We then plot one against the other and the slope of this line is the current expansion rate. When we do that, we get a value of around about 74 km/s per mega parex. Now, the other way we can measure this is to 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 come up with a model of all of the laws of physics that we know of that we can evolve that cosmic microwave background into the universe that we see around us today. We then find the best fit models for the universe and from that we can then determine many other different properties of the universe like the rate of expansion of the universe over time and in particular the current rate of expansion which when we do that we get a value of around 67 km/s per mega parc

which does not agree with that previous value of 74 that we get from the other method. Hence the crisis in cosmology or Hubble tension as it's known more formally. Statistically speaking, there's only around a one ina- million chance that a statistical fluke is the reason that these two measurements don't agree, which for obvious reasons has got a lot of people concerned. And so, two main camps have emerged for explaining this. Either it's not a real tension and instead there's something wrong with our observations of nearby galaxies, perhaps how we're calculating their distances, or it is real, and there's something wrong with our best model of the universe. Maybe we're missing something in our laws of physics or there's a component of the universe that we just don't know about yet. Now, there is a lot of ongoing effort trying to get to the bottom of this, especially for option one here, you know,

doublechecking all of our observations and measurements are correct. And a lot of that is coming from JWST as well because the distances to galaxies that we measure are based on many steps up what's known as the cosmological distance ladder of essentially measuring the distances to things much closer to us and then calibrating every successive further distance measurement that we make from there. So essentially it's all one big house of cards. So what the TD Cosmo collaboration have been doing is trying to measure the rate of expansion of the universe with a whole new method that doesn't rely on this distance ladder, this big house of cards.

Instead, they're using what is in effect a very simple idea, but one that's very difficult to actually do. They're measuring the time delay between two different paths that light can take from a background galaxy around a nearby galaxy. This is what's known as gravitational lensing. So our best theory of gravity, Einstein's theory of general relativity says that the effects of gravity can be described like massive objects curving space itself. Light travels along that curved space and then can get its path through space bent like how a lens bends light as well. This is how we end up with images like this where we can actually see the same background object twice or even three times or more because the light bends around a galaxy in the foreground which acts like a lens. But if one of those paths is slightly longer than the other, it will take the light a different amount of time to get to us. Measuring

the time delay along with the properties of that foreground galaxy doing the lensing gives us a direct measure of the distance, the absolute distance without needing to use the rungs of the cosmological distance ladder, this big house of cards that could be causing the Hubble tension. And specifically, we do this with background objects that flicker and vary like growing super massive black holes. That way we can measure the time difference between the flickers seen in the different light paths. So this is what the TD Cosmo collaboration have been doing for a number of years. Either often with just a single object that doesn't give the best statistics or with a really small number of lens sources. But earlier this year they published a sample of eight quazars growing super massive black holes that have been lensed by foreground galaxies that they managed to actually get time delay measurements

for. and also all of the detailed observations of the lensing galaxy that they need to do this very carefully. And using all eight of these, they managed to get a new independent measure of the expansion rate of the universe of 71.6 plus or minus around about 3.6 km/s per mega parc. It's smack bang in the middle of the two that don't agree annoyingly. But there are some very large uncertainties on that measurement still, which mean they can't quite draw very strong statistical conclusions just yet. But the collaboration reckon that if they can get JWT time on all eight of those quazars, then they should have the data they need to match the accuracy of the measurements from the other two major methods. It's really interesting to think how this might tie into the results from the dark energy survey that we've seen recently as well, which suggests that dark energy isn't constant, which would fall under option

two for explaining the Hubble tension. I've covered that in previous videos if you want to see more about that. But for now, it's too early to make strong conclusions just yet. This is just another interesting piece of the crisis in cosmology. All right, that's it for night sky news for this month. As always, if you snap any pictures of the night sky or you see any news stories that you want me to explain in a future Night Sky News episode, then send them my way over on social media cuz I'd always love to see them. But until next time, everybody, happy stargazing.

Hello and welcome to this episode. You see any news stories that you want me to explain in a future episode of Night Sky News while you're trolling the internet with me? You don't know if it's me if I don't use my two thumbs, right?

Questions about this episode

What is discussed in "JWST spots a star BEFORE it goes supernova | Night Sky News October 2025"?

In order: 0:00 Dr. Becky Smith, ExoMars, Ground News; 5:00 ExoMars, Ground News; 10:00 Hubble Space Telescope, Kilpatrick, NGC 1637; 15:00 TD Cosmo collaboration, Einstein's theory of general relativity.

What is mentioned in this Dr. Becky episode?

9 people, works and ideas are mentioned, including JWST, ExoMars, Ground News, TD Cosmo collaboration, Hubble Space Telescope, Dr. Becky Smith. Each one on this page links to its own page with every episode that mentions it.

How long is "JWST spots a star BEFORE it goes supernova | Night Sky News October 2025"?

The episode runs 22 min; the transcript is about 4,086 words in 27 timestamped sections.

More from Dr. Becky

About this transcript: the episode's spoken words as captioned on YouTube, split into timestamped sections. Reclip.Me locates every person, work and idea in the text, keeps the time it is first named, and quotes the words around it verbatim. Last updated January 24, 2026.