Space Nuts Episode 516: Angular Momentum, Cosmic Inflation, and the Infinite Universe
In this thought-provoking episode of Space Nuts, host Heidi Campo steps in for Andrew Dunkley, joined by the ever-knowledgeable Professor Fred Watson. Together, they tackle an array of fascinating listener questions that delve into the complexities of angular momentum, the nature of cosmic inflation, and the mysteries surrounding the universe's finiteness or infiniteness.
Episode Highlights:
- Angular Momentum Explained: Heidi and Fred kick off the episode by addressing a question from Buddy about angular momentum. They discuss how angular momentum affects spinning objects, the implications of expansion, and the intriguing concept of a potentially spinning universe.
- Time Dilation and Cosmic Inflation: Scott from Sydney poses a compelling question regarding time dilation during the universe's hyperinflation period. Fred elaborates on how time behaves under extreme gravitational conditions and the significance of inflation in explaining the universe's homogeneity.
- Is the Universe Finite or Infinite? The episode features a delightful audio question from young Enrique and his father Philip, exploring whether the universe is finite or infinite. Fred explains the concept of cosmic horizons and the challenges faced in determining the universe's boundaries.
- Temperature Control on the ISS: Kevin from Melbourne asks about the temperature inside the International Space Station (ISS) and how it varies with sunlight exposure. Heidi and Fred discuss the engineering marvels that maintain a livable environment for astronauts, including the challenges of thermal regulation in space.
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Stay curious, keep looking up, and join us next time for more stellar insights and cosmic wonders. Until then, clear skies and happy stargazing.
(00:00) Welcome to Space Nuts with Heidi Campo and Fred Watson
(01:20) Discussion on angular momentum and its effects
(15:00) Exploring time dilation and cosmic inflation
(25:30) Is the universe finite or infinite?
(35:00) Temperature control aboard the ISS
For the commercial-free versions of Space Nuts, join us on Patreon, Supercast, Apple Podcasts, or become a supporter here: https://www.spreaker.com/podcast/space-nuts-astronomy-insights-cosmic-discoveries--2631155/support (https://www.spreaker.com/podcast/space-nuts-astronomy-insights-cosmic-discoveries--2631155/support?utm_source=rss&utm_medium=rss&utm_campaign=rss) .
Episode link: https://play.headliner.app/episode/26820528?utm_source=youtube
00:00:00 --> 00:00:02 Welcome back to another episode of Space
00:00:02 --> 00:00:05 Nuts. I am your temporary host for
00:00:05 --> 00:00:07 today, Heidi Compo, and I'm here with
00:00:07 --> 00:00:09 the wonderful, again, delightful
00:00:09 --> 00:00:11 Professor Fred Watson, astronomer at
00:00:12 --> 00:00:15 large. 15 seconds. Guidance is internal.
00:00:15 --> 00:00:19 10 9 Ignition sequence start. Space
00:00:19 --> 00:00:25 Nuts. 5 4 3 2 1 2 3 4 5 5 4 3 2 1. Space
00:00:25 --> 00:00:29 nuts. Astronauts, report. It feels good.
00:00:29 --> 00:00:33 Hi Fred. How are you doing Heidi? I'm
00:00:33 --> 00:00:36 just doing lovely here in space city,
00:00:36 --> 00:00:39 Houston. It's actually a quite dreary
00:00:39 --> 00:00:41 evening. I think we have rain lined up
00:00:41 --> 00:00:44 all week long, but it's absolutely
00:00:44 --> 00:00:46 necessary. It's just probably not the
00:00:46 --> 00:00:48 best time with all of us grad students
00:00:48 --> 00:00:50 going into final exams. I was hoping for
00:00:50 --> 00:00:53 some sunshine to motivate us in the last
00:00:54 --> 00:00:56 few weeks. Yeah, it can have the
00:00:56 --> 00:00:58 opposite effect. I remember um when I
00:00:58 --> 00:01:01 was a student having to do exams in June
00:01:01 --> 00:01:05 when the sun was gloriously shining and
00:01:05 --> 00:01:07 you're sitting inside an examination
00:01:07 --> 00:01:09 hall. I found that um I found it easier
00:01:09 --> 00:01:11 to work when the weather was dreary I
00:01:11 --> 00:01:13 have to say. Oh yeah. I think you know
00:01:13 --> 00:01:15 the rain rain can be really good for
00:01:15 --> 00:01:18 studying. I I but it just it kind of
00:01:18 --> 00:01:19 brings your mood down. I think I mean I
00:01:20 --> 00:01:21 need some sunshine to break it up. We've
00:01:21 --> 00:01:23 got straight rain this whole week all
00:01:24 --> 00:01:25 through the weekend. We've got all all
00:01:25 --> 00:01:29 week of rain, but you know, it's not a
00:01:29 --> 00:01:32 buzzkill or a bummer is our questions
00:01:32 --> 00:01:35 for today. Yep. So, we have some really
00:01:35 --> 00:01:38 fun questions um lined up for you. And I
00:01:38 --> 00:01:39 think we're going to just jump right on
00:01:39 --> 00:01:42 into those. So, our first question of
00:01:42 --> 00:01:47 the day is from Buddy. And Buddy from
00:01:47 --> 00:01:50 Oregon asks, "Bre could you give me
00:01:50 --> 00:01:51 could you explain the other end of
00:01:51 --> 00:01:53 angular momentum to me? I know you
00:01:53 --> 00:01:55 explain how how angular momentum makes
00:01:55 --> 00:01:57 things spin faster as they compress. But
00:01:57 --> 00:02:00 what about when things expand? Does it
00:02:00 --> 00:02:02 have the exact opposite effect? Will it
00:02:02 --> 00:02:03 make things will it spread things out
00:02:03 --> 00:02:05 differently or make make things want to
00:02:05 --> 00:02:08 spin different or how does that work?
00:02:08 --> 00:02:10 And uh would that would the expansion of
00:02:10 --> 00:02:14 the unifor universe uh have that reverse
00:02:14 --> 00:02:16 angular momentum like from the from the
00:02:16 --> 00:02:19 big bang on? Could that have have been
00:02:19 --> 00:02:20 what the scap kind of what they talk
00:02:20 --> 00:02:24 about scapulting of the of the universe?
00:02:24 --> 00:02:26 Could that be what caused it? All right,
00:02:26 --> 00:02:27 just throwing it out there. Thanks,
00:02:27 --> 00:02:30 guys. Huge fan. Yeah, some great
00:02:30 --> 00:02:34 questions. Buddy always does. Um, so
00:02:34 --> 00:02:38 it's it's true that um uh angular
00:02:38 --> 00:02:41 momentum, it's the energy of object
00:02:41 --> 00:02:45 spinning. Um if you compress an object
00:02:45 --> 00:02:48 which is spinning, it will spin more
00:02:48 --> 00:02:50 rapidly. Uh and the the classic
00:02:50 --> 00:02:53 experiment of course is the office chair
00:02:53 --> 00:02:56 uh where um sitting at an office chair,
00:02:56 --> 00:02:57 you have your legs stretched out, you
00:02:57 --> 00:02:59 spin yourself around, pull your legs in,
00:02:59 --> 00:03:01 and sure enough, you're spinning faster.
00:03:01 --> 00:03:03 I used to do that when I had an office
00:03:03 --> 00:03:05 chair in an office and really annoy
00:03:05 --> 00:03:08 people uh when when it was a you know,
00:03:08 --> 00:03:12 it's a a common area. Uh so that that's
00:03:12 --> 00:03:15 correct. Yep. Um I can be annoying. I
00:03:15 --> 00:03:17 know. Uh most of the time actually I
00:03:17 --> 00:03:20 think uh the um the opposite is true. If
00:03:20 --> 00:03:22 you've got something that's spinning and
00:03:22 --> 00:03:26 it expands, then it will spin more
00:03:26 --> 00:03:29 slowly. Uh it's just the way angular
00:03:29 --> 00:03:33 momentum works. uh but the question
00:03:33 --> 00:03:35 whether the expansion of the universe
00:03:35 --> 00:03:38 after the big bang could be related to
00:03:38 --> 00:03:40 uh what Buddy calls a sort of reverse
00:03:40 --> 00:03:44 angular momentum uh and you know whether
00:03:44 --> 00:03:47 that concept ties into the idea of what
00:03:48 --> 00:03:50 we call the um we actually call it the
00:03:50 --> 00:03:53 the cosmic web that sort of scaffolding
00:03:53 --> 00:03:56 on which the galaxies are built uh
00:03:56 --> 00:03:58 forming the universe's large scale
00:03:58 --> 00:04:02 structure um I I think that's an
00:04:02 --> 00:04:04 interesting idea that you got the
00:04:04 --> 00:04:07 universe expanding. Now I have seen a
00:04:07 --> 00:04:10 headline recently that says that some of
00:04:10 --> 00:04:12 the things that I didn't read the
00:04:12 --> 00:04:15 article but I might do it for next time.
00:04:15 --> 00:04:17 Uh some of the things that we are
00:04:17 --> 00:04:20 mystified by about the universe today
00:04:20 --> 00:04:22 could be solved if the universe is
00:04:23 --> 00:04:26 spinning. Um but it's hard to imagine an
00:04:26 --> 00:04:28 object that is everything spinning.
00:04:28 --> 00:04:31 What's it spinning in relation to? Well,
00:04:31 --> 00:04:34 we don't know. But that spin um you
00:04:34 --> 00:04:36 know, it is possible it could be linked
00:04:36 --> 00:04:39 in the way that Buddy is describing. Uh
00:04:39 --> 00:04:42 I should go and chase up the uh the
00:04:42 --> 00:04:44 headline on the the spinning universe
00:04:44 --> 00:04:47 and see whether it does link to the sort
00:04:47 --> 00:04:50 of cosmic scaffolding that we see uh and
00:04:50 --> 00:04:52 uh to things like the mysteries of dark
00:04:52 --> 00:04:55 matter and dark energy which we so
00:04:55 --> 00:04:57 poorly understand at the moment. So um
00:04:57 --> 00:04:59 thank you buddy. That's a good question
00:04:59 --> 00:05:01 and it'll set me off on the track of
00:05:01 --> 00:05:03 investigation which I hope might lead to
00:05:03 --> 00:05:06 some more more succinct answers than the
00:05:06 --> 00:05:09 one you've had this morning. That can be
00:05:09 --> 00:05:12 a fun uh article to break Andrew back
00:05:12 --> 00:05:14 into the swing of things with, "Hey,
00:05:14 --> 00:05:15 Andrew, we're going to be talking about
00:05:15 --> 00:05:18 the entire universe in relationship to
00:05:18 --> 00:05:20 things we don't even understand."
00:05:20 --> 00:05:23 Good way to bring That's what we do
00:05:23 --> 00:05:26 every week. Yeah, it's true. It's true.
00:05:26 --> 00:05:29 Uh well, our next question is from Scott
00:05:29 --> 00:05:31 on your side of the world. So Scott
00:05:31 --> 00:05:34 Moonsir from Cindy, uh he says, "It
00:05:34 --> 00:05:37 appears to me that the hyperinflation of
00:05:37 --> 00:05:41 the universe in the first 10 um and then
00:05:41 --> 00:05:44 he has in parentheses - 34 seconds can
00:05:44 --> 00:05:46 be better explained by time violation
00:05:46 --> 00:05:49 due to the extreme gravitation
00:05:49 --> 00:05:51 experience at that time in the early
00:05:51 --> 00:05:54 universe. At the very first moment after
00:05:54 --> 00:05:57 the big bang, time would be virtually
00:05:57 --> 00:06:00 standing veritually standing still from
00:06:00 --> 00:06:02 the outside observer. Time would then be
00:06:02 --> 00:06:05 speeding up as the expansion progressed.
00:06:05 --> 00:06:07 So would So for an outside observer such
00:06:08 --> 00:06:10 as us, it would appear that the universe
00:06:10 --> 00:06:12 is much younger than it is. Please
00:06:12 --> 00:06:15 explain.
00:06:15 --> 00:06:17 Please explains a very famous comment
00:06:17 --> 00:06:19 made by a politician a number of years
00:06:19 --> 00:06:21 ago and uh it's got all kinds of
00:06:21 --> 00:06:23 connotations here in Australia which you
00:06:23 --> 00:06:26 won't be aware of Heidi. Uh so please
00:06:26 --> 00:06:28 please explain. Well, I will um but I
00:06:28 --> 00:06:29 can't I'm not sure I can give the
00:06:29 --> 00:06:34 answer. But it it's uh it there is
00:06:34 --> 00:06:37 um there there is time dilation
00:06:37 --> 00:06:41 uh when we look back uh at the early
00:06:41 --> 00:06:43 universe and you can measure that
00:06:43 --> 00:06:46 because you uh you can see for example
00:06:46 --> 00:06:50 how long supernovi take to these are
00:06:50 --> 00:06:52 exploding stars to rise to their peak
00:06:52 --> 00:06:53 brightness and then fade away. that
00:06:53 --> 00:06:56 length of time changes when you look in
00:06:56 --> 00:06:57 the early universe. It's actually
00:06:57 --> 00:07:00 stretched out because of time dilation.
00:07:00 --> 00:07:06 But um it's it's not it's not enough to
00:07:06 --> 00:07:09 give rise to this phenomenon that we
00:07:09 --> 00:07:13 call uh inflation. the this period uh
00:07:13 --> 00:07:16 exactly as Scott mentions uh for about
00:07:16 --> 00:07:19 the first 10 the minus 34 seconds after
00:07:19 --> 00:07:23 the big bang the universe expanded by a
00:07:23 --> 00:07:27 colossal amount uh it was um you know
00:07:27 --> 00:07:29 something like changed by a factor of 10
00:07:29 --> 00:07:34 ^ 50 in a length of time alike 10 the
00:07:34 --> 00:07:36 minus 32 of a second something we just
00:07:36 --> 00:07:39 simply cannot get our heads around um
00:07:39 --> 00:07:43 and that that is necessary not
00:07:43 --> 00:07:47 uh uh it's necessary and the reason why
00:07:47 --> 00:07:49 we believe that happened is that
00:07:49 --> 00:07:51 otherwise you've got a real problem uh
00:07:51 --> 00:07:54 in the homogeneity of the universe uh
00:07:54 --> 00:07:57 that the basically things are more or
00:07:58 --> 00:07:59 less the same in every direction. I
00:07:59 --> 00:08:01 won't go into it now but but that's what
00:08:01 --> 00:08:04 that in uh inflation scenario was
00:08:04 --> 00:08:07 actually improve um in introduced for to
00:08:07 --> 00:08:11 explain that overall uniformity
00:08:11 --> 00:08:14 um so time so it's not an artifact of
00:08:14 --> 00:08:16 time dilation we know it's a real
00:08:16 --> 00:08:19 phenomenon um time dilation as I said
00:08:19 --> 00:08:21 does exist it has been measured but it's
00:08:21 --> 00:08:25 not uh anything like the kind of violent
00:08:25 --> 00:08:28 expansion that was necessary to give
00:08:28 --> 00:08:29 rise to a universe that looks the way it
00:08:30 --> 00:08:31 does as we see it
00:08:31 --> 00:08:35 today. Good question, though. Very, very
00:08:35 --> 00:08:38 interesting. Our next question is from
00:08:38 --> 00:08:41 Phillip and his six-year-old son,
00:08:41 --> 00:08:44 Enrique from Portugal, and they have a
00:08:44 --> 00:08:46 very interesting um audio question that
00:08:46 --> 00:08:48 we're going to play for you here now.
00:08:48 --> 00:08:50 Good evening. Uh my name is Phillip, and
00:08:50 --> 00:08:53 I'm here with my six-year-old Enrique.
00:08:53 --> 00:08:58 Um we're uh sending this from Portugal.
00:08:58 --> 00:09:01 We listen to your show every night
00:09:01 --> 00:09:03 before falling asleep and and Enrique
00:09:03 --> 00:09:06 loves it. Uh he loves space and all
00:09:06 --> 00:09:07 things
00:09:07 --> 00:09:10 Cosmos and he's been wanting to send you
00:09:10 --> 00:09:14 a question since forever now. Uh but we
00:09:14 --> 00:09:17 didn't have uh a great question to ask
00:09:17 --> 00:09:21 you, but the other day remembered
00:09:21 --> 00:09:23 something and he thought of a question
00:09:23 --> 00:09:26 that he is curious about. So, I'm going
00:09:26 --> 00:09:30 to let him do his part now.
00:09:30 --> 00:09:35 Is the universe finite or infinite? And
00:09:35 --> 00:09:36 if it's
00:09:36 --> 00:09:41 infinite, what is it spanning into?
00:09:41 --> 00:09:44 Okay, so that's our question. Um,
00:09:44 --> 00:09:48 bye-bye. Say bye. Bye. Bye.
00:09:48 --> 00:09:50 Yeah. A question like so many of the
00:09:50 --> 00:09:52 ones we get from our listeners. And this
00:09:52 --> 00:09:55 is fantastic coming from young Enrique
00:09:55 --> 00:09:57 who's six years old. I wouldn't have
00:09:57 --> 00:09:58 thought of a proud profound question
00:09:58 --> 00:10:01 like this. When I was six years old
00:10:01 --> 00:10:02 because I probably didn't know what
00:10:02 --> 00:10:07 infinite meant in those days. Um so uh
00:10:07 --> 00:10:11 he he it's a question that astrophysics
00:10:11 --> 00:10:13 and cosmology simply don't have an
00:10:13 --> 00:10:15 answer to. Is the universe finite or
00:10:15 --> 00:10:18 infinite? We know uh that there are
00:10:18 --> 00:10:21 horizons in the universe beyond which we
00:10:21 --> 00:10:24 cannot see. And perhaps the best known
00:10:24 --> 00:10:27 one is the cosmic microwave background
00:10:27 --> 00:10:31 radiation uh which corresponds to us
00:10:31 --> 00:10:34 looking back in time uh to a time in
00:10:34 --> 00:10:37 which the universe was still glowing
00:10:37 --> 00:10:40 brightly uh and was opaque. Actually,
00:10:40 --> 00:10:42 you couldn't see through it. uh it was
00:10:42 --> 00:10:45 an opaque fog of brilliant radiation uh
00:10:45 --> 00:10:50 visible light in fact now uh that uh the
00:10:50 --> 00:10:52 if I put it this way the opakeness of
00:10:52 --> 00:10:55 the universe came to an end relatively
00:10:55 --> 00:10:58 quickly became transparent over a fairly
00:10:58 --> 00:11:00 short period of time and that's what
00:11:00 --> 00:11:03 enables us to look back to see this wall
00:11:03 --> 00:11:06 of radiation uh which we call the cosmic
00:11:06 --> 00:11:07 microwave background radiation as I
00:11:07 --> 00:11:09 think I've said before I call it the
00:11:09 --> 00:11:10 cosmic wallpaper because it's behind
00:11:10 --> 00:11:14 everything we can see uh in the in the
00:11:14 --> 00:11:17 universe. Um that radiation is a horizon
00:11:17 --> 00:11:20 that we can't penetrate with any of the
00:11:20 --> 00:11:22 technologies available to us today.
00:11:22 --> 00:11:26 Eventually maybe uh neutrino telescopes
00:11:26 --> 00:11:28 and gravitational wave telescopes might
00:11:28 --> 00:11:31 penetrate beyond that but at the moment
00:11:31 --> 00:11:33 we're limited to our electromagnetic
00:11:33 --> 00:11:35 wave telescopes and we can't see any
00:11:35 --> 00:11:38 further. So that is an art it's like an
00:11:38 --> 00:11:41 artificial horizon. It's like um I mean
00:11:41 --> 00:11:42 it's not artificial in the sense that
00:11:42 --> 00:11:45 it's humanmade. It's it's an illusion.
00:11:45 --> 00:11:47 Uh it's like when you when you're on a
00:11:47 --> 00:11:48 vessel on an ocean and you look all the
00:11:48 --> 00:11:51 way around, you can see a horizon which
00:11:51 --> 00:11:53 is the edge of your the limit of your
00:11:53 --> 00:11:55 visibility. But we know the ocean goes
00:11:55 --> 00:11:58 on a long long way beyond that. Uh and
00:11:58 --> 00:12:01 so um it's the same sort of thing. And
00:12:01 --> 00:12:03 the question is how far beyond that does
00:12:03 --> 00:12:06 it go in terms of the universe? Not the
00:12:06 --> 00:12:08 ocean, the universe. Um and the answer
00:12:08 --> 00:12:11 could be infinite. It could be that it
00:12:11 --> 00:12:13 is infinite. That's not ruled out by the
00:12:13 --> 00:12:16 cosmological models that we have today.
00:12:16 --> 00:12:19 Um now the idea of it expanding into
00:12:19 --> 00:12:23 something is again it's illusory. Uh all
00:12:23 --> 00:12:26 we know is that it's expanding. Uh but
00:12:26 --> 00:12:29 we also know that the shape of space
00:12:29 --> 00:12:30 changes dramatically on very large
00:12:30 --> 00:12:33 scales. Um and so it might not need
00:12:33 --> 00:12:35 anything to expand into. It might be an
00:12:35 --> 00:12:39 entity of its own right which is which
00:12:39 --> 00:12:41 is either infinite or finite. It's
00:12:41 --> 00:12:43 easier to imagine it when it's finite
00:12:43 --> 00:12:45 that sort of folds back on itself and so
00:12:45 --> 00:12:47 it doesn't have to have something to
00:12:47 --> 00:12:50 expand into. Of course, you can always
00:12:50 --> 00:12:54 invoke the multi-universe theories and
00:12:54 --> 00:12:56 perhaps suggest that there are extra
00:12:56 --> 00:12:57 dimensions that we don't see. We've
00:12:57 --> 00:12:59 talked about this before uh that the
00:12:59 --> 00:13:01 universe might be expanding into. Uh but
00:13:02 --> 00:13:04 all that is not yet supported by
00:13:04 --> 00:13:06 observations. It's got it's got you know
00:13:06 --> 00:13:09 it's conjecture mostly. So um Enrique
00:13:09 --> 00:13:11 you're asking fabulous questions. You're
00:13:11 --> 00:13:12 asking perhaps one of the most
00:13:12 --> 00:13:15 fundamental questions that astronomers
00:13:15 --> 00:13:18 can ask um along with a few like what is
00:13:18 --> 00:13:20 the nature of time and things of that
00:13:20 --> 00:13:21 sort but is the universe infinite I
00:13:22 --> 00:13:24 think is a great question. Maybe uh as
00:13:24 --> 00:13:27 you grow up uh cosmology will advance to
00:13:28 --> 00:13:30 the state where we can put an answer on
00:13:30 --> 00:13:32 it and we can say from the observations
00:13:32 --> 00:13:34 we can make of things like the cosmic
00:13:34 --> 00:13:37 microwave background cosmic wallpaper uh
00:13:37 --> 00:13:39 we might be able to say that there is a
00:13:39 --> 00:13:41 limit on whether it's finite or infinite
00:13:41 --> 00:13:44 and we hope maybe we'll talk about it on
00:13:44 --> 00:13:47 space notes as well. Well I just I love
00:13:47 --> 00:13:48 that question from Enrique. I remember
00:13:48 --> 00:13:50 being probably around that age and I was
00:13:50 --> 00:13:52 laying in bed one day and my little mind
00:13:52 --> 00:13:54 was just starting to think of these big
00:13:54 --> 00:13:56 ideas and I was trying to wrap my head
00:13:56 --> 00:13:58 around infinity and I just remember
00:13:58 --> 00:14:00 walking out of my room and I'm like,
00:14:00 --> 00:14:02 "Mom, I have a headache." And I was
00:14:02 --> 00:14:04 like, "Oh, my head hurts so much." And
00:14:04 --> 00:14:05 she's like, "Why? What's wrong?" I was
00:14:05 --> 00:14:07 like, "I'm thinking about infinity and
00:14:07 --> 00:14:10 it hurts my head." And I was just I
00:14:10 --> 00:14:12 could wrap my little tiny brain around
00:14:12 --> 00:14:14 it. And so they I'll say this to you,
00:14:14 --> 00:14:15 Enrique. If these are things that
00:14:16 --> 00:14:18 interest you and you would like to be
00:14:18 --> 00:14:21 somebody who helps solve these problems
00:14:21 --> 00:14:23 one day, you want to do good in school,
00:14:23 --> 00:14:26 especially with math because math is
00:14:26 --> 00:14:28 what they are using to define these
00:14:28 --> 00:14:31 things. So do good in school.
00:14:31 --> 00:14:34 Okay. All right. Our last question for
00:14:34 --> 00:14:38 the day comes from Kevin in Melbourne.
00:14:38 --> 00:14:40 And Kevin says, "Love the show, guys,
00:14:40 --> 00:14:42 and love sharing insights with my high
00:14:42 --> 00:14:44 school science class." Oh, I love to see
00:14:44 --> 00:14:46 it. We're going from the little kids to
00:14:46 --> 00:14:49 the older kids. Um, so Kevin has a
00:14:49 --> 00:14:52 question um about the ISS. What what is
00:14:52 --> 00:14:54 the temperature on the inside of the
00:14:54 --> 00:14:57 ISS? Does it vary from the side facing
00:14:57 --> 00:15:00 the sun to the side in relative shade?
00:15:00 --> 00:15:02 Does it increase when the ISS is in full
00:15:02 --> 00:15:04 sun and does it drop when the ISS goes
00:15:04 --> 00:15:07 behind the Earth? Does it make a lot of
00:15:07 --> 00:15:10 noise as it expands and contracts? How
00:15:10 --> 00:15:12 is the temperature maintained at a level
00:15:12 --> 00:15:15 compatible with human life? Have a great
00:15:15 --> 00:15:18 day and thanks for the podcast.
00:15:18 --> 00:15:20 You could probably answer this question,
00:15:20 --> 00:15:23 Heidi. You're an aficionardo of human
00:15:23 --> 00:15:26 space flight and
00:15:26 --> 00:15:28 well I don't know what the temperature
00:15:28 --> 00:15:32 is, but I do know that um you can follow
00:15:32 --> 00:15:34 the ISS on YouTube. There's a few
00:15:34 --> 00:15:36 channels where they have live streams
00:15:36 --> 00:15:39 going where they have some really
00:15:39 --> 00:15:42 fantastic camera angles of the ISS and
00:15:42 --> 00:15:43 it goes straight from NASA. You can see
00:15:43 --> 00:15:46 it on the official NASA channel. So, you
00:15:46 --> 00:15:48 can watch it go around the Earth and
00:15:48 --> 00:15:50 it's um I don't have this number off the
00:15:50 --> 00:15:52 top of my head. I could probably type it
00:15:52 --> 00:15:56 in really quick, but it's what 72 times
00:15:56 --> 00:15:59 72 sunrises in a day. It's No, it's um
00:15:59 --> 00:16:03 it's uh it's about I think it's 17 uh I
00:16:03 --> 00:16:04 think you got the numbers the wrong way
00:16:04 --> 00:16:07 round. Yeah. Um so so it's every 90
00:16:07 --> 00:16:10 every 90 minutes you get a sunrise and
00:16:10 --> 00:16:12 every 90 minutes you get a sunset. So
00:16:12 --> 00:16:15 you get one of them every 45 minutes. Um
00:16:15 --> 00:16:18 so I think it's 17 of each that you get
00:16:18 --> 00:16:19 during the day. It's an easy
00:16:19 --> 00:16:20 calculation. I can't do it in my head.
00:16:20 --> 00:16:24 Anyway, um I think in terms of um no,
00:16:24 --> 00:16:26 this is a great question and it's um
00:16:26 --> 00:16:29 it's a tribute to the engineering behind
00:16:29 --> 00:16:31 the ISS that you can do this sort of
00:16:32 --> 00:16:35 thing at all. So the I think the uh
00:16:35 --> 00:16:39 internal interior temperature on the ISS
00:16:39 --> 00:16:43 is about 20° C, maybe 21, something like
00:16:43 --> 00:16:45 that. I can't do it in my head. Oh, wait
00:16:45 --> 00:16:48 a minute. 20 is 60 6° F. Is that right?
00:16:48 --> 00:16:51 Yeah, they keep it between 64 to 79
00:16:51 --> 00:16:53 degrees F. Yeah. Yeah. So, so there you
00:16:53 --> 00:16:55 go. Thanks for looking that up. I hope
00:16:55 --> 00:16:57 that's on the That's official NASA.
00:16:57 --> 00:16:59 Careful careful where you get your space
00:16:59 --> 00:17:02 news. Absolutely. That's right. So, it's
00:17:02 --> 00:17:04 a sort of ambient temperature that um
00:17:04 --> 00:17:07 and that and that allows astronauts to
00:17:07 --> 00:17:08 work in church sleeves and things of
00:17:08 --> 00:17:12 that sort without overcoats on. Um uh
00:17:12 --> 00:17:15 but uh it's artificially controlled. So
00:17:15 --> 00:17:18 that's all governed by air conditioning
00:17:18 --> 00:17:20 units that actually heat and cool the
00:17:20 --> 00:17:22 atmosphere. Uh because you're absolutely
00:17:22 --> 00:17:26 right uh the as the spacecraft goes in
00:17:26 --> 00:17:30 and out of direct sunlight, it's uh its
00:17:30 --> 00:17:32 temperature the amount of radiation it's
00:17:32 --> 00:17:37 feeling uh in varies enormously. Um the
00:17:37 --> 00:17:40 that in itself needs to be controlled as
00:17:40 --> 00:17:43 well. Uh so on the hot when when it's
00:17:43 --> 00:17:45 being heated up by the sun, you've got
00:17:45 --> 00:17:47 to try and get rid of that heat into
00:17:47 --> 00:17:49 space and there are radiators that do
00:17:49 --> 00:17:52 that. Um at the same time when you're on
00:17:52 --> 00:17:54 the other side, you've you want to try
00:17:54 --> 00:17:57 and conserve the heat uh when you're
00:17:57 --> 00:17:58 when you're on the dark side, when
00:17:58 --> 00:18:01 you're in the the Earth's shadow. Um so
00:18:01 --> 00:18:05 so this this is all taken care of in the
00:18:05 --> 00:18:08 engineering. Um the metals that are used
00:18:08 --> 00:18:11 are ones whose expansion and contraction
00:18:11 --> 00:18:12 characteristics are very well
00:18:12 --> 00:18:15 understood. Uh and they you know they're
00:18:15 --> 00:18:17 built in such a way that there's a lot
00:18:17 --> 00:18:20 of self-compensation built into it. Um a
00:18:20 --> 00:18:24 bit like um you know biometallic strips
00:18:24 --> 00:18:25 and things like that when you put two
00:18:25 --> 00:18:26 different metals together with different
00:18:26 --> 00:18:29 expansion coefficients. Nevertheless,
00:18:29 --> 00:18:30 it's a really interesting question that
00:18:30 --> 00:18:32 I don't know the answer to and I don't
00:18:32 --> 00:18:34 know whether you would Heidi either. uh
00:18:34 --> 00:18:37 whether it caks as it warms up and and
00:18:37 --> 00:18:39 um you know cools down, whether there's
00:18:39 --> 00:18:42 a noise from the space station as it uh
00:18:42 --> 00:18:44 as it goes into the sunlight. I wouldn't
00:18:44 --> 00:18:46 mind betting there is. You know, I would
00:18:46 --> 00:18:49 assume I'd assume there is. I was uh I
00:18:49 --> 00:18:52 was at a talk from an astronaut um a
00:18:52 --> 00:18:55 couple years ago and he was giving the
00:18:55 --> 00:18:57 funniest story about their A-Red device,
00:18:57 --> 00:19:00 which is the exercise device they use on
00:19:00 --> 00:19:02 the spacecraft and it's if you look at
00:19:02 --> 00:19:04 it, it's it's huge. If you guys go to
00:19:04 --> 00:19:06 your regular gym, probably one of the
00:19:06 --> 00:19:07 biggest machines in there might be
00:19:08 --> 00:19:09 something like the leg press. So, this
00:19:09 --> 00:19:11 looks like that on such a larger scale.
00:19:12 --> 00:19:13 And that's because they have all these
00:19:13 --> 00:19:16 vibration um mufflers built in because
00:19:16 --> 00:19:18 they can't have Yeah. They can't have
00:19:18 --> 00:19:20 these exercise devices creating a lot of
00:19:20 --> 00:19:22 vibration. So, they have these dampeners
00:19:22 --> 00:19:24 built in. And there was one day where
00:19:24 --> 00:19:26 the it wasn't working like it was
00:19:26 --> 00:19:28 supposed to. And the astronauts still
00:19:28 --> 00:19:29 had to get their exercise in, but they
00:19:29 --> 00:19:31 didn't want to have all this vibration
00:19:31 --> 00:19:34 rattling apart the station. And so they
00:19:34 --> 00:19:37 solved this problem with the most clever
00:19:37 --> 00:19:39 um genius thing you would think of. Can
00:19:40 --> 00:19:42 you take a guess at how they fixed this
00:19:42 --> 00:19:44 probably multi-million dollar problem?
00:19:44 --> 00:19:47 Oh gosh. Uh probably bits of cardboard
00:19:48 --> 00:19:51 stuck in between a sock. They shoved a
00:19:51 --> 00:19:54 sock in the little squeaky spot. So, and
00:19:54 --> 00:19:56 it's it solved the problem and it worked
00:19:56 --> 00:19:59 just fine. And so, I would assume if
00:19:59 --> 00:20:01 we're needing to fix things by sticking
00:20:01 --> 00:20:03 socks in the corners to dampen the
00:20:03 --> 00:20:05 vibrations, I would guess I think it's
00:20:06 --> 00:20:08 probably safe to guess that it probably
00:20:08 --> 00:20:10 does make little creeks and sounds as it
00:20:10 --> 00:20:13 heats up and cools down. But another
00:20:13 --> 00:20:14 interesting thing I learned this past
00:20:14 --> 00:20:17 weekend um that kind of is a direct
00:20:17 --> 00:20:19 answer to Kevin's question about how
00:20:19 --> 00:20:21 does that temperature get controlled? A
00:20:21 --> 00:20:25 lot of it is just complex patents. And
00:20:25 --> 00:20:27 Intuitive Machines, which is another
00:20:27 --> 00:20:29 company in the space industry, has
00:20:29 --> 00:20:31 recently partnered with Colombia
00:20:31 --> 00:20:34 Sportsear. And you might be thinking,
00:20:34 --> 00:20:36 well, Colombia Sportsear, what does that
00:20:36 --> 00:20:38 have to do with space? So Colombia,
00:20:38 --> 00:20:40 their patent portfolio for the
00:20:40 --> 00:20:42 technologies they put into their jackets
00:20:42 --> 00:20:45 that keep you warm in winter conditions,
00:20:45 --> 00:20:48 their patent portfol portfolio is 500
00:20:48 --> 00:20:50 times bigger than any of their other
00:20:50 --> 00:20:52 leading competitors. And that is
00:20:52 --> 00:20:55 technology that I maybe I can't explain
00:20:55 --> 00:20:57 or understand or maybe I can't even look
00:20:57 --> 00:20:59 at it unless I was look I had an NDA and
00:20:59 --> 00:21:01 was looking at those patents. But their
00:21:01 --> 00:21:03 whole thing is they want to keep hot
00:21:03 --> 00:21:04 things hot and cold things cold. And
00:21:04 --> 00:21:06 sometimes those things are right next to
00:21:06 --> 00:21:09 each other. And that's really I think a
00:21:09 --> 00:21:11 very Kevin's question is so interesting
00:21:11 --> 00:21:14 and dynamic and multifaceted like it's
00:21:14 --> 00:21:16 really hey how do we keep people alive
00:21:16 --> 00:21:17 and comfortable up there? And it's the
00:21:17 --> 00:21:20 answer is it's very complicated.
00:21:20 --> 00:21:24 Yeah. It's um it's interesting that that
00:21:24 --> 00:21:26 link is one that I never would have
00:21:26 --> 00:21:28 guessed would happen. But um I just
00:21:28 --> 00:21:30 thinking back you know to the early days
00:21:30 --> 00:21:33 of space flight the the Mercury capsules
00:21:33 --> 00:21:35 and the Geminy capsules and and even
00:21:35 --> 00:21:38 Apollo um those problems of how you
00:21:38 --> 00:21:41 maintain a comfortable environment for
00:21:41 --> 00:21:43 astronauts to work in was solved at a
00:21:43 --> 00:21:46 very early stage in the history of space
00:21:46 --> 00:21:48 flight. Not on the same sort of scale as
00:21:48 --> 00:21:51 the space station which is vast compared
00:21:51 --> 00:21:53 with the these other early capsules but
00:21:53 --> 00:21:55 nevertheless they they had to deal with
00:21:55 --> 00:21:58 it. they had to work out ways of keeping
00:21:58 --> 00:22:01 the spacecraft at a comfort comfortable
00:22:01 --> 00:22:03 temperature inside despite the huge
00:22:03 --> 00:22:06 variations of radiation uh that it's
00:22:06 --> 00:22:08 feeling on the outside. So, uh it's
00:22:08 --> 00:22:11 probably quite old technology, but it's
00:22:11 --> 00:22:12 great that it works and it's a tribute
00:22:12 --> 00:22:16 to the uh yes to the ingenuity of humans
00:22:16 --> 00:22:18 when it comes to putting human beings in
00:22:18 --> 00:22:19 an environment that they were never
00:22:19 --> 00:22:22 meant to be in uh in terms of uh of
00:22:22 --> 00:22:25 their well-being. Um maybe we were we
00:22:25 --> 00:22:27 were meant to be in them in terms of our
00:22:27 --> 00:22:30 exploration, but uh that's a different
00:22:30 --> 00:22:32 question.
00:22:32 --> 00:22:34 I just every every time we get together
00:22:34 --> 00:22:36 and talk, Fred, I'm I'm just left with a
00:22:36 --> 00:22:38 very positive feeling about the
00:22:38 --> 00:22:40 incredibleness of human beings and what
00:22:40 --> 00:22:42 we've invented and come up with and it
00:22:42 --> 00:22:44 makes me just, you know, proud of our
00:22:44 --> 00:22:47 species. We have done wonderful things
00:22:47 --> 00:22:49 and we've continued to create incredible
00:22:49 --> 00:22:52 things. I've even seen that um some
00:22:52 --> 00:22:55 people have built these devices that are
00:22:55 --> 00:22:57 helping refereeze and rebuild the ice
00:22:57 --> 00:23:00 caps and it's like that is a fantastic
00:23:00 --> 00:23:02 invention and it's really cool just like
00:23:02 --> 00:23:06 these engineering breakthroughs.
00:23:06 --> 00:23:09 Absolutely. Engineering is um yeah it's
00:23:09 --> 00:23:12 uh it's right up there with science as
00:23:12 --> 00:23:14 one of the most important things that we
00:23:14 --> 00:23:16 can do for the well-being of our species
00:23:16 --> 00:23:19 and long may it continue.
00:23:19 --> 00:23:21 Absolutely. Well, thank you so much,
00:23:21 --> 00:23:22 Fred, for answering all of these
00:23:22 --> 00:23:26 questions today and enlightening us with
00:23:26 --> 00:23:28 your knowledge. You're just you're
00:23:28 --> 00:23:31 you're just a wealth of of fantastic
00:23:31 --> 00:23:33 information. And it has been my absolute
00:23:34 --> 00:23:36 pleasure to be a co-host with you these
00:23:36 --> 00:23:39 last few weeks. And uh for those of you
00:23:39 --> 00:23:41 listening, you will have Andrew back
00:23:41 --> 00:23:43 your next episode. So, look forward to
00:23:43 --> 00:23:46 him. But I will be signing off for now.
00:23:46 --> 00:23:48 Well, Fred, did you have anything else
00:23:48 --> 00:23:51 you wanted to add? Just once again, a
00:23:51 --> 00:23:53 thank you to you, Heidi, for um making
00:23:53 --> 00:23:56 Andrew's absence um I I won't say a
00:23:56 --> 00:23:58 pleasure because he'd think I was glad
00:23:58 --> 00:24:01 to see the back of him, but uh certainly
00:24:01 --> 00:24:03 a delight. It's been very nice to talk
00:24:03 --> 00:24:06 to you. Thanks again. Excellent. Well,
00:24:06 --> 00:24:08 you guys can have me back anytime. And
00:24:08 --> 00:24:10 for those of you listening, wish me luck
00:24:10 --> 00:24:12 on my final exam so that I can join my
00:24:12 --> 00:24:15 place among the stars of of the
00:24:15 --> 00:24:18 superstars of the engineers and people a
00:24:18 --> 00:24:20 part of this industry. And thank you so
00:24:20 --> 00:24:23 much for having me on Space Nuts. Space
00:24:23 --> 00:24:25 Nuts. You've been listening to the Space
00:24:25 --> 00:24:28 Nuts podcast
00:24:28 --> 00:24:31 available at Apple Podcasts, Spotify,
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00:24:38 --> 00:24:43 podcast production from bites.com.