Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / #388: Galacticide

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#388: Galacticide · Space Nuts: Astronomy Insights & Cosmic Discoveries

0:00
Hi there, Thanks for joining us. This is Space Nuts. My name
0:04
is Andrew Dunkley, your host, and glad you could join us once again.
0:08
Coming up on today's program, we are going to be looking literally at
0:12
the oldest black hole yet scene. It's not only the oldest, it is
0:18
big, in fact huge, and it's very, very hungry. We'll also
0:23
be looking at an asteroid impact on Earth. Yes it happened. Why are
0:27
we still here? Fred will explain, And the mars kopter has run into
0:32
some communications issues. We'll cover all that, plus audience questions at a bit
0:36
of homework coming up on this edition of Space Nuts fifteen second guidance in channel
0:44
ten nine ignition sequence Space Nuts NY four three two more review ones Space Nuts
0:55
as the night record it Bill's goods and joining us to hash out all of
1:00
that and much much more is Professor Fred Watson, Astronomer at Large. Hello
1:04
Fred, Andrew, what a surprise to see you there. I was expecting
1:11
someone else, but it was you, So I'm very happy about that.
1:15
Yeah, just as well, isn't it? Really? Nobody else would put
1:19
up, would put up with our respectives for a terrible bunter. Anyway,
1:25
I'm here and I'm glad you're there and all is well. It's going to
1:29
be hot day for you, I think the West. Yeah, we're getting
1:33
some really big numbers at the moment, thirty nine today, forty tomorrow,
1:37
forty for Australia Day Friday, and then we might get a brief respite into
1:45
the weekend proper. But yes, stinking hot. I imagine it's also going
1:49
to be very windy on Australia Day, so I imagine we'll have fire weather
1:53
warnings and all sorts of stuff. Dogs and cats living together, that's my
1:57
favorite line. But yeah, it's all. It's all a bit hellish around
2:02
here at the moment. I think I'd be better off pitching a tent on
2:06
the sun. At this point in time, Western, it's getting back to
2:15
a normal Western. Some of the last couple have been quite mild, so
2:17
this one. The last summer we only had one day over forty degrees,
2:23
and this season we've had I think this is probably the sixth or seventh,
2:28
so it's it's been very hot summer. Now let's get down to business.
2:35
The James Webb Space telescope has been added again and Fred and this time it
2:40
spied the oldest black hole yet seen, and it is a monster and it
2:45
is committing astronomical suicide by destroying its own galaxy. By the sound of it,
2:52
it's a very interesting story. Galacticide. I guess it would be,
2:57
wouldn't it. That's what it would be. Part arttery side is when you
3:00
kill your dad galactoside. Yeah, that's I think we've just invented something there.
3:07
It is a good word. Yeah, I'll just write it down so
3:09
I don't forget it. Yeah, do that? Do that? Yeah,
3:14
there you go here you uniting galaxy. Remember where you've heard it first,
3:19
folks, So yes. So observations are led by from a team of international
3:24
astronomers led by scientists at the University of Cambridge in the UK, and they
3:30
used the James Web telescope to look at some very early galaxies and by that
3:37
I mean with a very long look back time. So you're looking back to
3:40
not very long after the birth of the universe. When we're talking now about
3:45
time probably about four hundred million years after the Big Bang. So the Big
3:50
Bangs are currently estimated to be thirteen point eight billion years ago, so this
3:55
goes back thirteen point four billion years. These observations and yes, what has
4:01
been discovered is a massive factor super massive black hole at the center of this
4:09
galaxy. And by that they I don't think they've got a particularly precise number
4:15
for it yet because it's so far away, but it is a few million
4:18
times the mass of the Sun, and that puts it very much in the
4:23
super massive region. And basically what it does throws another upset into our understanding
4:31
of how galaxies and black holes form and grow. So, just to recap,
4:43
black holes seem to come in two sorts, the stellar mass black holes
4:47
the mass typically of a star, a large star, but maybe twenty twenty
4:51
times the mass of the Sun, and super massive black holes, which are
4:56
millions to billions of times the mass of the Sun, with very little between
5:00
the intermediate mass black holes which are thought to exist, and in fact some
5:03
might be looking in the insides of what we call globular clusters of stars,
5:08
but they're still very much more elusive than either the stellar mass black holes or
5:13
the super massive black holes. So how does supermassive black holes get so big?
5:16
The thinking has always been that they start off with stellar mass size,
5:23
you know, modest sized black holes, just a few, maybe tens or
5:28
even hundreds of times the mass of the Sun, and they grow over time
5:32
by accreting other materials. So if you've got one in the center of a
5:36
youthful galaxy, there's a lot of gas in there. That gas can be
5:41
sucked in to the black hole. That's the accretion process and causes its mass
5:47
to increase. But the problem is that is thought to be a process that
5:55
takes billions of years. So you start off with something small and it grows
5:59
to a super mass black hole over a period of as I've said, billions
6:01
of years, and this is only four hundred million years after the Big Bang,
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and so you know, it's essentially thrown the cut among the pigeons.
6:12
It's saying, well, how can we get a black hole this size so
6:15
early in the universe. And the two ways that are being postulated are,
6:21
first of all, maybe black holes, super massive black holes form in other
6:28
ways, excuse me. They might come into being as a supermassive black hole
6:32
rather than come into being as a stellar mass black hole and then grow,
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or they can gobble up material the surroundings. In other words, they can
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accrete, to use the technical term, much more rapidly than was thought to
6:49
be the case, and they're estimating it would have to be about five times
6:55
the rate of gobbling up that we've been you know, the astronomers have been
7:01
working with so far. The number that comes from studies of how we think
7:04
black holes accrete material and grow. So that's the current states. We've got
7:13
this conundrum, a black hole that should have taken more than a billion years
7:17
to grow to the size that it has, but it's done it in four
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hundred million years, and so it's it is a puzzle. Well yeah,
7:27
and in doing what it's doing, it's also destroying everything around it, but
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it seems to be doing it in an unusual way. There's this reference to
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an ultra fast wind that's been caused by this process, and that's what's destroying
7:46
the galaxy. Rather than eating the galaxy, it's actually destroying it's for one
7:51
of a better term food source that just sounds really yeah, it does,
7:57
doesn't it. And so the wind itself, I mean normally things that come
8:05
out of black holes, and don't they don't come out of the black hole
8:07
itself, they come out of the accretion disc Normally, the pattern is that
8:11
you've got a black hole, it builds a kind of disk of material around
8:16
it which is gradually swirling into the black hole, and that's how it's gobbling
8:20
up. And some of that material doesn't go into the black hole. It's
8:24
diverted by magnetic fields into what we call polar jets, jets that come out
8:30
at right angles to the disc. And that's the wind. But it looks
8:35
as though there's something else going on here. I don't know too much about
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this type of wind because I would have expected, you know, if you've
8:43
got something that's really gobbling up material around it very quickly, the wind will
8:48
be directed perpendicular to that disc. But it may well be that under some
8:52
conditions you get a wind that's that's sort of blowing everywhere, what we would
8:56
call isotropic in all directions. But yeah, it is as you said,
9:03
that is maybe pushing away the gas that this black hole needs to keep on
9:09
growing, and eventually that would stop the black hole from accreting. The black
9:16
hole wouldn't go away, it would still be there, but it wouldn't be
9:18
gobbling up material any more. It would become what we call a quiescent black
9:22
hole, which is a bit like the one at the center of our own
9:24
galaxy. So really interesting stuff. One of the lead authors says, this
9:33
is the most exciting time in his career. It's a new era. The
9:37
giant leap in sensitivity, especially in the infrared, is like upgrading from Galileo's
9:41
telescope to a modern telescope overnight before Web came online. I thought, maybe
9:45
the universe isn't so interesting when you go beyond what we could see with ourble
9:48
Space telescope. But that hasn't been the case at all. The universe has
9:52
been quite generous in what it's showing us. And this is just the beginning.
9:56
It's almost poetic, isn't it very very poetic? And yeah, it
10:00
also is that points out the fact that the James Web Space Telescope has,
10:07
as promised, delivered. A lot of the time they say this is the
10:09
next big thing it's going to do, you know, yay, yay,
10:13
and then it goes up again. Oh it's a blob out of focus.
10:20
But this one's actually delivering, and it's delivering spectacular results, very much so.
10:26
And the hope is that the telescope will be able to probe even further
10:31
back in time to look at even earlier black holes, and that might give
10:35
some clues as to what's going on in the early history of black holes.
10:39
If we start finding dozens of these super massive black holes at a very early
10:43
stage of the universe, I think it means we've got to do some really
10:46
serious rethinking of what's going on in those early galaxies. Yes, indeed,
10:56
and this one's certainly thrown everybody in a spin because of a how old it
11:01
is, be how big it is, and see what it's actually doing to
11:05
its neighborhood and how it's doing that. It's all very Yeah, it's sort
11:11
of thrown the baby out with the bathwater in terms of theory in some respects,
11:16
I suppose. So, yeah, we find these things and it opens
11:20
up so many more questions, but they will hopefully ultimately lead to answers that
11:26
that's the that's the hope, isn't it. Pret that's the way science works.
11:31
Yes, that's right. So we've got you know, we've got observations
11:37
which dog fit the theory that exists. So you rebuild the theory and then
11:39
do more observations to see whether the theories upheld. This very much the way
11:43
astronomy works, even at these great distances from from our from our own present
11:50
time, great distances in time. M all right. If you want to
11:54
chase up that story about this incredible discovery and this this the Strange black Hole,
12:01
fizz dot org pH y s dot org is the website where you can
12:05
find that article. This is Space Nuts Andrew Dunpley here with Professor Fred Watson.
12:13
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not be disappointed. It's the best in the business. Believe me. I've
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been using it for a couple of years. Now. Now back to the
14:56
show. Okay, we've tacked all four systems. Now, Fred, let's
15:01
move on to something that happened more recently than that black hole forming. In
15:07
fact, this happened only a few days ago. Earth was hit by an
15:11
asteroid. It has been reported in the popular press, and we're still here
15:18
to talk about it. Now. What I understand is this one wasn't as
15:20
big as the one that killed off the dinosaurs. But I have heard a
15:24
report that they're a small lizard with a limp after this one. Will Yeah,
15:33
they don't have too many lizards out and about in January in eastern Germany.
15:41
Whatever, let's have previous truth here in the way of a good joke,
15:43
though Fred quite so. Yes, so an object that was largely well
15:52
recorded by you know, by security cameras and dashcums and all the rest of
15:58
it. An object that came to earth over Berlin, in fact, in
16:03
the east and half of Germany over the weekend Sunday morning their time, so
16:08
lots of video and a lot of people really interested in it. It's got
16:15
a name as all good aid sorry, all good asteroids do. So it's
16:19
obviously being counted as an asteroid even though it was a small object. Its
16:26
name is twenty twenty four b x one, and you might remember that the
16:30
way those numbers work is the date of the year twenty twenty four. The
16:36
bee says it was the second half of January when it was discovered, because
16:41
it's alphabetical for each half month throughout the year. It's very cleverly done,
16:45
and then the alphabetical order and then a number after that. So it's landed
16:52
outside Berlin. The interesting bit is that it was an astronomer in Hungary.
17:03
And I think I don't know whether this gentleman Christian Sonski, I think is
17:08
how we would anglicize his name. I don't know whether he's an amateur astronomer
17:15
or a professional, but he discovered it and alerted the International Astronomical Union via
17:21
there's an asteroid discovery system that he can use, and that was then confirmed
17:29
by NASA, presumably with one of those telescopes. And this all happened kind
17:34
of twenty minutes before the impact. I think the discovery was made several hours
17:38
before impact. NASA confirmed it twenty minutes before impact with absolutely spot on prediction
17:48
of where it would where it would land or where it would disintegrate over and
17:56
at what time, and it was all right on the money. So this
17:59
is interesting because it's the eighth time that an asteroid has been discovered before it
18:07
hits the Earth, and that's telling you that the systems are working, particularly
18:14
because this is thought to be about a meter across, so it's what you
18:18
would call a very small asteroid and maybe a large meteoroid. There's a that's
18:25
a sort of gray area between the two. So yeah, it's it's very
18:30
very you know, satisfactory outcome of what we're hoping to do in the world
18:37
of of planetary protection, as it's called, this idea of trying to monitor
18:45
threats composed by asteroids before they happen. The other thing is that the gentleman
18:52
who I mentioned, Christian Sanski, forgive me if I'm mispronouncing his name,
18:57
has discovered three that have been hitting the Earth. In other words, first
19:06
he's done three of these eight asteroids that have been discovered before they hit the
19:10
Earth. Very well known asteroid hunter, yes, and seems to be very
19:15
good at what he does. Now, this one, as you said,
19:18
around about a meter, which is a little bit smaller than the one that
19:23
hit the Earth and brought about the beginning of the end of the dinosaurs.
19:27
That one was as big as Mount Everest or something, wasn't it. And
19:33
this one broke up on impact. But they do think that it would have
19:37
showered parts of Europe with micro meteorites. I think they referred to the mass.
19:45
Yeah, so lots of small bits of debris and it's possible that some
19:49
of them might be recovered. It's you know, it's wintertime up there.
19:56
Meteorites are generally black, and often that discovered in Antarctica, where they're against
20:02
a white background because of snow. Maybe they will be discovered perhaps in the
20:07
in the regions of eastern Europe where this object is thought to have fallen.
20:12
Bits of this object I thought to have fallen. So if you do want
20:17
to if you're a listener from that part of the world and you would want
20:19
to go out and hunt for these micro media writes, just just keep an
20:23
eye out for limping lizards and you might you might get laggy. Yeah,
20:30
I think yes, I think you'd probably be luckier to find a lizard than
20:33
you would meteorite. At this time of year, the lizards will be well
20:40
hibernating. I think they would. But yeah, so when you hear the
20:44
word is asteroid, you automatically think about the dinosaurs and the andsurs frocks that
20:49
have hit Earth in the past, and you make that assumption. So when
20:53
when you hear that we've actually been hit by an asteroid, you go,
20:56
oh no, but they're not always monsters that no, they're not. In
21:03
fact, that's the interesting part about it. At the moment, you know,
21:06
all these telescopes that are looking for asteroids are concentrating on the small ones
21:11
because the big ones, most of them have already been found. She's good
21:15
news, Yeah, we just we've actually got to watch out for the ones
21:18
that are just a bit big enough just to get through. They're the ones
21:22
to Yeah. Did we talk about that last week when I was talking about
21:27
the asteroid Protection group that I was sitting with in Vienna. Yeah, they
21:33
postulated a scenario in which, exactly as you said, I want to kill
21:37
a meter asteroid could get through. It has to be in a very unusual
21:41
orbit, but it's possible. Never say never. But we've done the double
21:48
asteroid redirection test and we know it works. So yeah, we live in
21:55
hope. Exactly. Well, you had your you had your T shirt on
21:57
last week, didn't you the double storgery direction. Yes, that's right.
22:03
Now let's move on to Mars, and the Mars Copta has made the news,
22:08
and that's because it stopped working. In fact, I think it was
22:12
in the middle of a flight when it lost comms with NASA and they thought
22:17
end of mission. So yeah, it got a bit scary there for a
22:22
while, but then it suddenly went nothing to see here, it's all good.
22:26
I'm here, I'm here. So what do we know about this?
22:30
So exactly as you said, So it's not the first time. Let's just
22:36
preface it. It's not the first time. That the copter has suffered communications
22:41
issues and I think the longest was two months or something that it was,
22:48
oh, there you go, two months. But this was something different from
22:55
that, and what they were doing was doing a test flight. This is
23:03
last week and it was wait for this, This number blows me away and
23:07
drew. It was Ingenuity's seventy second lift off off the planet Mars, when
23:14
it was originally planned to have five flights. So seventy two is just an
23:19
astonishing number and it's been so invaluable to the Perseverance mission, so that's fantastic
23:26
stuff. Anyway, it was a quick test that they were doing. I
23:30
think it was basically just an up and down. In fact, they described
23:37
it as a quick pop up vertical flight to check out the helicopter systems following
23:41
an unplanned early landing during its previous flight, so there was an issue with
23:45
the previous flight, and then they did this up and down, but as
23:48
it was coming down, it lost communications again before touchdown. Now, the
23:55
great thing is this helicopter is equipped with basically autonomous systems, and it has
24:00
to be because you know the delay, the time delay between signal leaving Earth
24:06
getting to Mars and then coming back again is far too long to control helicopter
24:11
with, so it's got its own brain and it does its own decisions and
24:17
apparently landed safely. Although it's out of sight of Perseverance itself, they can't
24:26
actually see it, so there is talk or the worst talk of Perseverance actually
24:33
having a quick drive over to have a look at it a visual inspection,
24:37
just to see if it's okay. But at least it's talking to Perseverance,
24:44
so they've got you know, they've got communications restored. And apparently there was
24:52
a post on x formerly Twitter asking if Ingenuity would fly again, and JPL
24:59
Jet Propulsion of the Boro Tree, who run the whole show, said that
25:03
they are going to be a setting the new information that's come from that before
25:07
they'll decide whether it'll fly again. So that may have been its last flight.
25:11
And the other hand, it may just very sad it would be silent,
25:15
and you know, it's just done such an extraordinary job of reconnaissance in
25:23
the area around Perseverances, but apparently covered seventeen kilometers and gone up to twenty
25:30
four meters, which is quite quite a height for a little baby helicopter like
25:34
that, And I think the other thing that's right at one point eight killograms.
25:41
It's rotors, if I remember right here, one point two meters well,
25:45
two of them rotating in opposite directions so that they balance out the talk.
25:49
The thing that gets me though, is, you know, Martian knights,
25:55
the temperature way goes way down, probably the minus sixties and things like
26:00
that, And in fact, the average temperaturep males is minus sixty three.
26:06
I think if I remember rightly, somebody might correct me if I've got it
26:08
wrong just remembering. But Martian nights are very, very cold, and the
26:15
solar panels which are sit on top of the rotors are absolutely vital for keeping
26:22
it warm by the electric current that they generate for its batteries during the day,
26:27
which then keep the little spacecraft warm. Not really a spacecraft. It's
26:33
an aircraft, isn't it. They keep it warm during the night. It's
26:38
been one of the great success stories of NASA for it to have lasted heck
26:44
of a lot longer than they plant seventy two missions versus the plant five,
26:48
but also to survive the prostile conditions for such a long time. That's amazing.
26:56
Yes, an extraordinary success story. Were full of admiration for the engineers
27:02
who invented it and built it. Basically, Yeah, and hopefully not the
27:07
last we'll see of it, but if it is, it's still been a
27:10
resounding success. You mentioned X formerly known as Twitter. Did you hear that?
27:18
I've forgotten the name of it? You Tube, Twitter and Facebook are
27:23
going to merge. Did you hear about this? It's going to be called
27:26
it didn't? Yeah, it's going to be called you Twitch base. I
27:33
should have seen that one coming, shouldn't. I probably dead? Oh boy,
27:41
listen. I was going to save this till later, but I think
27:44
we will tackle it now. It's a bit of homework. Last week we
27:49
were talking about a dark energy survey where it brought into question our understanding of
27:56
the cosmological constant. Now we've had a question from Lindsay asking us to explain
28:02
the equation of state, the value of the cosmological constant, which is minus
28:07
point one. But this survey has re jeeked that number be minus point zero
28:15
eight. But what we didn't do, and I probably should have asked the
28:18
question at the time, is what is that? How do they work that
28:23
out? What is the equation of state? It comes from physics really Andrew's
28:30
you might not be surprised, and it comes from considerations of a perfect fluid,
28:36
which has its own definition. So if you merge in the universe as
28:40
a perfect fluid, you can characterize it by this number, which is the
28:45
equation of state. It's equal to the ratio of its pressure to its energy
28:52
density, and it's it's sort of, you know, it's part and place
28:57
of thermodynamics. The pressure to the energy density ratio doesn't really you know,
29:04
it doesn't really feed much into our understanding of what's happening in the in the
29:11
far universe. But in the case that we're talking about, which is the
29:17
cosmological equation of state, the the equation of state as the universe, of
29:21
the universe as a whole, and how it relates to the accelerated expansion of
29:26
the universe, it's it's, uh, it actually kind of kind of makes
29:33
makes more sense. I'm going to just try and read a little bit about
29:41
the equation of state from the good old Wikipedia website. Uh, the accelerated
29:45
expansion of the universe can be characterized by the equation of state of dark energy.
29:51
So it's the dark energy itself, who's equation of state you're looking at.
29:55
In the simplest case, the equation of state of the cosmological common that's
30:00
what we were talking about last week, is minus one in this case.
30:06
The I won't go into more detail, but if you've got an acceleration of
30:18
an equation of state which is less than minus one third, then you've got
30:26
you've got a different status and I think I think you've got basically something that
30:34
changes with time. That's the bottom line of it all. I'm not explaining
30:38
this very well at all, Andrew, and I hope there aren't any cosmopologists
30:42
listening or else that the turning in their well, not in their graves,
30:45
but they're turning in their beds, So there is there's something. There is
30:51
another hypothetical thing that comes into it as well, which is phantom energy.
30:56
That's a term I'm not familiar with. Phantom energy is you know, it's
31:03
said the hypothetical form of energy which actually has a different characteristic in the equation
31:10
of state. In other words, it's less than minus one. So it
31:15
basically it's it's a lot of quite deep physics, which is, as you're
31:22
no doubt noticing, not that easy to put into simple words. No,
31:26
I can imagine. Well, I just heard it at the pot of flo
31:33
is the dark energy survey we talked about last week has put a question mark
31:37
over the equation of state of the cosmological constant. Thank you very much.
31:48
That's blood you're here, and that's the simple that's the simple explanation. And
31:55
there's only what a five percent chance that the minus point one is still relevant.
32:01
Yeah, it's actually it's it's minus it's it's minus one. I'm not
32:08
sure you might be looking at something slightly different, but it is minus one
32:13
that he's thought to be. And I think this the value was rather smaller.
32:16
Wasn't it minus point eight or something like that? Yeah, something like
32:20
that. Yep, yes, you're right, and what I yeah, I'm
32:25
just looking at the article now minus point minus one and now it's looking like
32:30
it's minus point eight. So yes, my ologies, but yeah, thanks
32:36
for the question, Lindsay. Nice to be able to follow that up and
32:38
get a let's call it an explanation. This is space, not Andrew Dunkley
32:45
here, Professor Fred Watson space buds. Now, Fred, let's see if
32:54
we can answer some questions on other matters. And the first and I forgive
33:00
me if I've missed your name up because it just couldn't quite catch it in
33:05
the dialogue. In fact, I might even say your name because you've got
33:07
to say it for us. Hello, Fred, thank you for a great
33:10
book. My name is Manny Jabery and in Sweden, and I sent the
33:15
question about why is astronomy important? Thank you for that answer. I've been
33:21
thinking a lot of celestial objects rotate, spin, like our planet, our
33:28
solar system, the stars, the galaxies and even black holes if I understand
33:34
it correctly. My question is does the universe rotate? And is it possible
33:40
that we have misinterpreted the expansion of the universe but in reality it's just spins
33:45
and we are moving away from objects like the moon is escaping Earth. Thank
33:52
you again, and a morn I think he said, but I'm sorry I
33:58
forget that wrong. Does the universe rotate? The whole universe? Apparently not?
34:07
And you know the question that you immediately asked and Andrew is how would
34:12
we know what that was? The next Yeah, how do you know if
34:17
it's rotating or not? Because you're in it and the universe by definition is
34:22
everything that we can we can you know, we can observe or or understand
34:30
detect. So it's it's basically one of these questions though that people do and
34:39
ask in exactly the way that we've just heard this morning, sorry today,
34:46
That is because it's a natural thing to ask that that everything in the universe
34:52
seems to rotate, absolutely everything, But is the universe itself rotating? And
34:59
I guess the best way to put it is that there is no evidence that
35:07
the universe is rotating by any means that we we you know, we investigate
35:15
whatever means we use to investigate it. There's no evidence that we do that
35:21
we do find a rotating universe. So the bottom line is the fact that
35:32
we you know, we have to We're sitting in the universe itself, and
35:39
the only things that we can measure, certainly at cosmological distances, are the
35:45
red shifts that the expansion of the universe, the way it's you know,
35:51
the way shape is changing, if I can put it that way. Even
35:52
though we don't know whether the universe has a shape, we can we can
35:57
detect its expansion. So that is one of the things that we do know
36:00
that the universe is expanding. I have seen articles in the past that say.
36:07
That suggests that I haven't ever followed this up, so I don't know,
36:12
you know, what the details are. I should do that it'd be
36:15
a bit more homework. That suggests that if the universe was rotating, we'd
36:20
be able to travel backwards in time. That seems a very unlikely scenario to
36:27
me, because relative relativity doesn't like the idea of backward time travel. You
36:31
can go forward, but not backwards. So it's yeah, one that might
36:37
be worth following up. But yeah, no evidence that the universe is rotating.
36:42
It. Okay, this is a really simple explanation on my part,
36:46
but I could. I can imagine if it was rotating it it'd be like
36:51
a glass of water. You know, when you've got a glass of water
36:53
and you put something in the water and then you rotate the glass that it
36:59
doesn't really effect what's inside, you know what I'm saying. So even if
37:02
it was rotating, it might not do anything. Yeah, that's an interesting
37:08
analog because it almost counteracts the argument because if you were inside a glass of
37:15
water that it was rotating, what you'd see would be the effect of the
37:20
centrifugal force of the water being pushed outwards, and you might think you were
37:24
in an expanding glass of water. If they carry that to the universe,
37:30
you know, somebody's going to say, oh, it's expanding because it's it's
37:32
rotating. But then but that lies there being Yeah, that's what one was
37:37
asking, though, don't know because the second part of his question was if
37:42
the universe is rotating, does that change the expansion theory? Yeah, so
37:46
I yes, I missed that bit. I was too busy worrying about the
37:51
rotation of the universe. It's thought not to be and the you know,
37:57
the the I guess one of the things that comes into this. Sorry,
38:04
I'm floundering for words here. One of the points is that if we take
38:14
the traditional definition of a universe, which is everything we can see or measure
38:19
or detect, then we would have no way of knowing if it's rotating,
38:22
because there's no frame of reference outside it within which it's rotating, so that
38:28
the answer would be no. And I think the only way that you could
38:32
contemplate a rotating universe will be by accepting the premise that there are other universes
38:38
out there, that ours is just one of many universes. Then if you
38:44
take that step, then you might have the possibility that it's rotating, but
38:47
as I said, there's no evidence that it is. Okay, yeah,
38:52
gee, it certainly dredges up all sorts of questions and ideas and it made
38:59
them very big water cooler to stand around and talk about this. I think
39:05
a great question. Thanks thanks for sending it in. Let's go to a
39:08
text question. This one comes from Lachlan in James in Minnesota. It says
39:20
hello from the great state of Minnesota. That's a coincidence because that's where I
39:22
thought he was from right off the bat. Thank you so much for your
39:25
educational insight and incredibly down to earth Unintended podcast. You make standing at the
39:32
Meal so much more enjoyable. I started at the very beginning of your show,
39:37
and I'm currently in the middle of May twenty twenty one, so I've
39:39
got ways to go before I catch up. But my question is a bit
39:45
of an abstract one. Suppose you discover an anomalist telescope of irrelevant size,
39:52
and what makes this telescope anomalist is that when you look through it, it
39:55
will show you whatever celestial body it's pointed at in real one to one time.
40:02
What is the first thing you would look at supposing there's nothing in the
40:07
way, both from a standpoint of personal choice and a broader standpoint of humanity
40:13
as a whole. Wanting to learn as much as we can about the universe
40:16
very much. Looking forward to hearing your thoughts. Thanks Fellows. James in
40:22
Minnesota. So you've got a telescope you can look anywhere in the universe in
40:27
real time, what do you look at? Fred? First and foremost,
40:36
I think we've discussed this before, actually, Andrew, I'm trying to remember
40:39
what I said. Then we do get questions like this from time to time.
40:45
Yeah, just yes, I think it's a it's a similar question to
40:47
what we've had before. So yeah, I mean what I would really like
40:54
to see, and it's not really aligned with this question particularly well, But
41:00
if I could take a telescope anywhere and look, I would love to see
41:07
our galaxy from the outside. So not only would I be wanting to see,
41:13
you know, this hypothetical telescope to see anything instantaneously without the delay of
41:19
time, Then not only would I want to do that, I'd want to
41:23
move it as well, so I could see what the sweep of our galaxy
41:28
would look like from the outside. So it's taking the question a little bit
41:30
further than than James probably intended. Maybe I'm answering a different question, but
41:37
that's what I'd like to do. Take this hypothetical super duper telescope, plunk
41:43
it something like one hundred thousand light years above the pole of our galaxy.
41:50
Might be a dangerous place, actually, because the pole of our galaxy has
41:52
occasionally known been known to be the source of some high energy material coming from
42:00
the super super massive black Collar. The middle of the galaxy could be a
42:04
dangerous place, but it will give you a beautiful view dale on the spiral
42:08
structure of our galaxy. And that's what I'd love to see. Okay,
42:12
now that's a good answer. I wouldn't have thought of that for me,
42:15
James. Let's just stretch this as far as we possibly can. Literally,
42:21
I would want to see the actual edge of the universe. I'd want to
42:25
see what's going going on beyond the visible universe. You said, assuming nothing's
42:30
in the way, Well, let's just move all that stuff out of the
42:32
way. I would point the telescope and I could go any direction I want
42:37
and just find the actual edge of the expanding universe to see what's going on.
42:43
That's what I want to see because that's one of the great mysteries.
42:46
So for me, that's the answer. What do you reckon, Fred,
42:52
Well, we don't think it's got an edge. Let's assume it has,
42:58
so I'd want to be going on out there at the expansion point, whatever
43:04
it is. That's that's where my brain, I mean, just to some
43:08
extent, we yeah, yeah, it is interesting because you know, we
43:15
what we see when we look as far out as you are talking about there,
43:19
we see the cosmic microwave background radiation. But that's because we're looking back
43:23
in the past. What James is saying is you're not looking back in the
43:27
past. You're looking at what it is like now, and so it could
43:31
be infinite. You might not run against an edge, Andrew. That's the
43:37
conundrum of cosmology. We don't know whether the universe is infinite or not.
43:40
But that's why we want to have a look. That's why I want to
43:45
I want to loan of James as tell us. So it's a very you're
43:50
you're You've given a very profound answer there, which which I applaud. It's
43:53
better than mine. I love these I love these what if questions we get
44:00
sentation, I know they're good fun. Thanks James. And our final question
44:04
this week is from Ian. However, this is Ian from Cambridge. Just
44:08
got a central question. What is the temperature of space around the Earth orbit
44:17
from the Sun, so the distance from the Earth. So what's the temperature
44:22
of space? I asked the question because when I google it it says it's
44:27
about two point seven Calvin. But then you hear the James Webb telescope that
44:32
one side is very very hot, on the other side of the shield is
44:37
cold. So don't understand how general temperature of space from distance from a sum
44:46
is only two kelvin. Appreciate me let me know. Thank you very much.
44:52
Okay, we'll be sending you an email. Oh, ask for Red.
44:58
What's the temperature of space? I think when he refers to one side
45:00
of the James Web being hot on the other side being cold, that's that's
45:05
because of the radiation effect, isn't it the Sun? Whereas in general space,
45:09
which is what it is, nothing ish, there's a temperature I imagine,
45:19
and that's what he's asking about in the vicinity of Earth. So yes,
45:23
so the background temperature of space is indeed two point seven degrees kelvin.
45:30
And what that is is the radiation from the Big Bang. It's the it's
45:37
actually the temperature of the cosmic microwave background radiation. So when you look at
45:42
we just talked about it, you're looking back so far in time. You're
45:45
seeing a time when the universe was still glowing brightly. It was still luminous.
45:49
It's now visible in radio waves microwaves because of the expansion of the universe,
45:55
stretching the visible light wavelength out to microwave wave spifactor of about thirteen hundred
46:00
I think beriightly. So that's the underlying temperature of space, and it is
46:08
indeed two point seven we can generate, believe it or not, here on
46:14
Earth temperatures colder than that, much much nearer to absolute zero than that two
46:20
point seven degrees. So on Earth you can generate cold temperatures. But exactly
46:25
as you've said, in the vicinity of a star like the Sun, you've
46:34
got radiation coming from that object. It doesn't affect the temperature of space itself,
46:40
but as soon as that radiation falls on another object, then it heats
46:45
it up. It's exactly how infrared radiation works. So it's it is.
46:52
It is a higher temperature on the surface that you're measuring. But if you
46:59
were out in the middle of nowhere in space and you two point seven degrees,
47:06
it would be what we call a bilometer. Actually, a bilometer is
47:07
a device that measures temperature cross all wavelengths. Right, two points degrees is
47:14
the right answer, So then your bufflement is understandable. But that's that's the
47:20
correct answer. I'm just done that. I actually got one right, So
47:24
I did. You were right? It'll body, Yeah, you don't.
47:29
You could just have a go on the question of state as well. I
47:34
couldn't do this. I wouldn't do this by myself. Yeah, thank you,
47:37
Ian. It's a great question and it certainly cleared that up. And
47:44
we appreciate your questions and your comments. And even if you want to send
47:46
us corrections, we ignore that, but you can send them anyway buia our
47:51
website, via our website, space nuts podcast dot com, or space nuts
47:55
dot io. We'd love to hear from you, whether it's in ten next
48:00
door audio form. If you do send an audio question or even the text
48:04
question, don't forguest, forget to tell us who you are or we are
48:07
from like James in Minnesota, who is going to invent a new telescope.
48:13
It's going to be good, be called the James at Minnesota Space Telescope,
48:15
and it will see everything in real time. That would be an absolute you'd
48:21
make. You'd make a couple of dollars out of that, unless you sold
48:22
it to the government. Then they'd make you pay to give it to them.
48:25
But anyway, I'm lovely to hear from all of you, and Fred
48:30
as always, thank you. That brings us to the very end of this
48:34
episode not too early. Thank you, Andrew. Good to talk and we
48:42
might speak next time too. We might. Fred Watson, Astronomer at Large,
48:49
as always, we thank him for his very precious time. And to
48:52
Hugh in the studio, thank you too for reasons I'll have to look up
48:58
and from me, Andrew Dunkley, good to have your company. I hope
49:00
you can join us on the very next episode of Space Nuts. Bye bye.
49:06
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