The Supermassive Podcast - 51: BONUS - Wobbly Planets and Baby Names

Episode Date: April 10, 2024

Can wobbly planets have more than two solstices? Are we earthlings receding from the sun and the other planets? What is dark flow and why is it controversial? When stars die, is their energy lost forever?  Send your questions to [e-mail] or find us on Instagram @SupermassivePod.  The Supermassive Podcast is a Boffin Media production for the Royal Astronomical Society. The producers are Izzie Clarke and Richard Hollingham. 

Hello and welcome to another bonus episode of the Supermassive podcast from the Royal Astronomical Society with me, science journalist Izzy Clark, astrophysicist Dr Becky Smethurst and the society's deputy director Dr Robert Massey. This is the place where we dive into the Supermassive mailbox and answer all of your questions. It really is Supermassive at the minute as well, isn't it? Because you guys have the best questions. It's accreting at an alarming rate exactly it is but we have been entrusted with a great responsibility this message comes from the adventures of buckley and they say hi i really enjoy your podcast my partner and i recently found out we're having a baby and are researching baby names. Oh, congratulations.

We wondered if you could help with your favourite astronomy space-themed names. Thank you. I mean, where do you start, really? Congratulations. I was thinking, you know, my colleague Lucinda has a cat called Kepler, and I'm more comfortable offering people pet names than baby names by some margin really um yeah i mean you could name them after star names is probably i guess but there must be thousands of possibilities right that names like the first things that sprung to mind were like

very astronomy themed names which i'm not sure if they fit into that favorite category but they're like aracoth arcturus you know just like really lean into it yeah i was trying to think of ones that were maybe a little bit more like you could get away with it and if you unless you knew you know like you wouldn't know so i was thinking like moons of the solar system right is one of the greatest places to start especially for girls names right because uranus's moons are just all shakespeare characters right yeah yeah you got ariel belinda b Bianca, Cordelia, Cressida, Juliet, right?

Like name a few at the start of the alphabet, right? But then also Phoebe is the moon of Saturn if you wanted to go for a Phoebe. Oh, that's true. You know? And there's Miranda as well, moon of Uranus. Yeah, exactly. And then also I found for boys,

so Zeke is obviously like the shortened form of Ezekiel in like a hebrew and that's quite a popular name but in arabic zeke z-e-k-e means like shooting star oh so it's quite a nice little connection as well but then also you've got like every astronaut as inspiration right if it's a girl it could be valentina after valentina tereshkova the first woman in space or if it's a boy it could be yuri or alan or neil right they go under the radar love that not enough neils exactly but i think you can find like an astronomy spacey connection with like so many names that people just don't realize that like even ones that are more common

like for example louise or paul after louise webster and paul murdin who discovered the first black hole cygnus x Oh, there we go. There's so many possibilities. Paul Murden was my colleague at the RAS, so this is only going to go to his head if he's listening, but a shout out to Paul anyway. Other ones that I considered were constellations. So Lyra or Leo, those are ones that sort of fly under the radar a little bit,

but if you know, you know. Yeah, exactly. So congratulations, Adventures with Buckley. ones that sort of fly under the radar a little bit but if you know you know yeah exactly so congratulations adventures with buckley i hope that helps or maybe that has just told you exactly what you don't want either way that is some sort of an answer either way let us know what you decide guys because we'd love to welcome the new little buckley into the universe yeah okay on to the questions becky yukadek vejponza has this question about the expansion of space and i'm really sorry if i've got your name pronunciation wrong there um but they say space itself is expanding and that makes galaxies receding from each other faster than the speed they are moving does that mean within the galaxy or within each star system each object

is spreading further away from each other as well even within our solar system are we earthlings receding from the sun and the other planets what is the extent of this spreading right i get this question a lot actually and a lot of people think this and yeah i always have to explain it so space itself is expanding everywhere yes but the gravity holding together like the solar system or galaxies is strong enough to hold those objects in place relative to each other so that the space that the distance between them doesn't grow even though the space itself is expanding right which is kind of hard to wrap your head around a little bit and visualize,

but no, we are not like receding away from the sun or from other planets because of the expansion of space. That's not true for like galaxies though. Like obviously in a galaxy, the stars are held together in the same way, but outside of galaxies, galaxies are receding away from each other because the separation is so great that the pull from the expansion of space is often stronger than the pull of gravity between them except when they're close enough together like in a big galaxy cluster they might end up like merging together or for the milky way and for andromeda right which are getting closer together because the pull of gravity is strong enough to sort of overcome that expansion so i kind of like

think of it as like sort of like the stilts of a pier right like water will move around them as the tide goes out but the stilts still stay in one position right and the same distance from each other because the force holding them there is stronger than the pull from the water thanks becky okay and robert amanda Gasser emailed in with this question and says, Is it possible for a planet to be so wobbly that it could have more than two solstices? Oh, I can't say this word. Two solstices. Solstices it is.

So wobbly that it could have more than two solstices per year. That's a great question. It's a great question, isn't it? Yeah, it's hard to imagine a planet like that because it would be, you know, that's something very dramatic has happened in its formation process and it's not, I suspect, it's not going to be very stable in the long term. And the seasons on Earth happen with a pretty stable axis. You know, you might think the Earth's axis is wobbling around the Sun. It's actually only doing that on a very long time scale,

but it's pointing more or less to the part of the sky near the pole star. That's why the pole star in the northern hemisphere is always in the same place in the sky. And what happens as the Earth goes around the Sun is that effectively one hemisphere, well, in the winter, the southern hemisphere is tilted towards the Sun, and as we go around the other side, it's the northern hemisphere. So the axis isn't actually wobbling around very dramatically. There are small cycles. sphere. So the axis isn't actually wobbling around very dramatically. There are small cycles.

On a really, really long time scale, it does change direction on about 26,000 years. It wobbles around and that does have a long-term effect on the climate and seasons. But if you had a planet of the type you're describing where, say, that kind of change was happening, you know, every time it went around its orbit, then you would get very chaotic weather, I think, at the very least. The interesting thing, I suppose, in our own solar system is if you look at a planet like Mars at the moment the actual tilt of Mars is not very different to the Earth but it doesn't have a moon to stabilise it and there's evidence that it changes its tilt a great deal from almost zero right down to about 80 degrees. Now what that will mean is that there are times when it's an icy planet and times when it's an icy planet and times

when it's tilted right over that maybe the hemisphere facing the sun for a long period of time warms up a lot so these things do matter and it does really have a dramatic impact on the weather uh you know so i'm not sure i want to live on a planet where the the axis is wobbling around that much because i think it would be really really can you remember what kind of time scale that mars's axis wobbling happens on i'm trying to remember i i think it would be really, really inclement. Can you remember what kind of timescale that Mars' axis wobbling happens on? I'm trying to remember. I think it's millions of years. I don't think there's very convincing evidence over exactly when it's been in that position,

but the idea is that you might get, maybe that's a period when it was warmer as well. You know, it's not just this long-term change over the thickness of the atmosphere. It's really intriguing to me, at least in the sense you think, well, when it's in this position where the axis is tilted over and you get say a whole well about what it would be about 10 months long half a martian year where it's warm enough perhaps for water to melt so for ice to melt and become water temporarily you know that's that must be really interesting but i don't think and sadly none of us are gonna be around to actually see this act so we just have to probe going to look at the evidence again okay i'm be Becky, Yandri Griffin has emailed to say,

Hi, my name's Yandri. I'm 16 years old and I'm an aspiring astrophysicist. Hi, Yandri. Hello. Very recently, I've come across the weird, hypothetical and controversial concept of dark flow. I find it fascinating and I have heard that there's some controversy on whether it exists or not

i would like to know what becky thinks and if evidence for dark flow is compelling enough as well as what would be causing dark flow so becky starters what is dark yeah because we're getting deep with this one yandere another good question so this dark flow idea really only comes from one study back in like 2008 2009 and they found in sort of like old data of the cosmic microwave background from the w map satellite that there were galaxies in the same patch of sky that all appeared to be moving with similar speeds in roughly the same direction that's weird all the galaxies should be right? In terms of they should have random velocities, random directions in which they're moving. And when we say directions, like yes, the overall

direction of all of them is away from us because of the expansion of space, but they do have some local velocities as well when you correct for that. That should be the case. It should be completely random, unless there's some massive thing that's pulling on all of the galaxies and pulling them in that direction right and it's this apparent pulling of those galaxies appearing to all be moving in the same direction that got dubbed the dark flow now by 2013 we then had much more improved data from the plank satellite And a big team of researchers from that collaboration found there was no evidence for this dark flow and published it in a paper. But then one solo member of the Planck team did publish a paper saying that the Planck data agreed

with the previous claim of this dark flow using WMAP. So that's where the sort of controversy is. Now, I haven't looked into this much myself so i don't think i know enough to come down on one side of the fence or not but i i do trust the plank team did their due diligence and didn't find anything but if it was there i think it's really fun to speculate like what it could be and one idea would be that it could be a bubble universe izzy do you remember this from our multiverse episode so yeah if there's like another universe like a second universe a multiverse next to ours in that direction that could be the massive thing that's pulling on all those galaxies in that direction and causing this claimed dark flow and the thing is i you know dark flow even if it's that dark flow is such a

a weird name to choose for it i can get why because it's like oh there's something there that we don't know what it is and we can't see so that's where the idea of like dark comes from from dark matter and dark energy but like dark flow like i mean you can tell a man named it that's all i can say yes i was just gonna say it's not the one is it really outrageous and on that note robert gareth arnold muzzley has this question about stars you never know what you're gonna get on this podcast oh no honestly honestly no gareth's question is if stars burn fuel to produce light and energy does that energy continue to exist in the universe but in other forms or is it lost forever in other words when all the stars die

out in the future will the energy they've produced be elsewhere or lost for good? Yeah, that's a great question, Gareth. AKA a hard one. The translation is we just heard from Robert last episode. Yes, absolutely. It's pretty much what I say to all of them, really, isn't it? So yeah, it's a great, i.e. hard question. But the energy definitely continues to exist.

The conservation of energy is a thing. You don't create or create or destroy it however you could also argue that it's lost it's put beyond use so as it disperses it's irrecoverable essentially so if you think about say a star like our sun it radiates lots of energy into space a tiny tiny bit of that warms and illuminates the earth and the other planets and asteroids and comets. Most of it radiates out into the wider universe. And right, I suppose you could argue that a few photons of that enter some hypothetical extraterrestrial's eyes standing on another planet around another star. But most of it's dispersed. And so you could argue it's lost. temporary effects like, you know, where there's local gravitational pulls pulling things together and so on. Eventually, if you go forward, say, 10 to the power of 100 years, which is 10 followed by one followed by 100 zeros in years, so very, very, very long time, when all the stars have

exhausted their fuel and died out and cooled down and dispersed in material space, and even black holes may have decayed, then the universe will end up with all that energy smoothed out in a kind of equilibrium, more or less. And as time passes, that should be more and more the case. And that's described as the heat death, although it's actually really quite a cold death of the universe as it gets bigger and bigger. So the answer, Gareth, is, you know,

you're actually right that the energy both continues to exist, but also it's sort of lost in the sense that we can't access it very easily either. Not lost to the universe, though. That's a nice note to end on, isn't it? The end we can't access it very easily either not lost to the universe though that's a nice note to end on isn't it the end of the universe yeah it's not lost to the universe it's just irrecoverable oh well thank you for the questions everyone and do keep them coming you can email podcast at ras.ac.uk and we're also on instagram at supermassivepod we'll be back next time with an episode all about the voyage emissions which i am very excited for but until then everybody happy stargazing