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Astronomy Q&A: Super Jupiters, Light Echoes & Cosmic Mysteries · Space Nuts: Astronomy Insights & Cosmic Discoveries

0:00
Andrew Dunkley: Hello again. Thanks for joining us on a Q and
0:03
A edition of Space Nuts. My name is
0:05
Andrew Dunkley. This is where we answer
0:08
audience questions. And, uh, Daryl
0:11
is asking, uh, could we witness the birth of
0:14
our sun? That's looking at old
0:17
light, I suspect. Uh, we also, uh,
0:20
um, uh, have a question from Rennie, who
0:23
wants to know what we might solve over the
0:25
next hundred years in astronomy and space
0:27
science. Uh, Dave is asking about a
0:30
super Jupiter with a mo moon the size of
0:32
Earth. It's a bit of a what if question. And
0:35
Cal is asking about whether or not a
0:38
gas giant could become a star.
0:41
Fred will be answering all of those questions
0:43
on this episode of space nuts.
0:46
Generic: 15 seconds. Guidance is internal.
0:49
10, 9. Ignition
0:51
sequence start.
0:53
Professor Fred Watson: Space nuts.
0:53
Generic: 5, 4, 3, 2.
0:55
Andrew Dunkley: 1.
0:55
Generic: 2, 3, 4, 5, 5, 4, 3, 2,
0:58
1. Space nuts. Astronauts report it
1:01
feels good.
1:03
Andrew Dunkley: You'll also be answering the question as to
1:04
why sometimes when you push a button, nothing
1:06
happens. Hello, Fred.
1:09
Professor Fred Watson: That's usually because you've pressed the
1:11
wrong button.
1:12
Andrew Dunkley: I pressed the right button, but
1:15
it didn't do anything. So
1:17
it used to happen on the radio a lot.
1:21
Professor Fred Watson: Press a button and nothing happens.
1:22
Andrew Dunkley: Yeah, because. And you know what? It's a
1:25
quirk of the digital age. When we worked in
1:27
analog radio, a button was a button
1:30
until it broke.
1:32
Professor Fred Watson: Yeah, that's right.
1:33
Andrew Dunkley: But in the digital age, uh, you press the
1:35
button and that goes, nah, nah, I don't want
1:38
to do that. No, sorry. Go find
1:41
something else to push.
1:42
Professor Fred Watson: Need a reboot?
1:43
Andrew Dunkley: Yeah, indeed. How you been, Fred?
1:46
Professor Fred Watson: Very well, thank you. Yes, um, uh, you know,
1:49
just relishing, uh, being back home and, uh,
1:52
being back into the routine with Space Nuts,
1:54
uh, twice a week.
1:55
Andrew Dunkley: Yes, indeed. Although it's so close to the
1:57
end of the year, we were just about to go
2:00
into summer recess or Christmas New year
2:02
recess. But we won't. I don't think we'll
2:04
take a heck of a long time off. Uh, we'll
2:07
work it out. We've got to work it out. Uh,
2:09
now I've got four text questions,
2:12
and, um, we get a lot more
2:15
text questions than we do audio, so I thought
2:17
we'd bump a few of these off
2:19
politely. Uh, so let's get to our first
2:22
one.
2:23
Uh, g', day, Space Nuts. When we look up,
2:26
um, uh, when we look up at our space,
2:28
we're always looking back in time.
2:32
So when we look at Andromeda, the light was,
2:34
uh, that we see is two to two and a half
2:36
million years old. Could we train our
2:38
telescopes to see light from four and a Half
2:41
billion years ago and see our sun
2:44
being born? My guess is no, but I
2:47
love the idea of it. That comes from Daryl in
2:49
South Australia who is a patron. Thank you,
2:52
Daryl. Um, much appreciated. So, um, yeah,
2:55
if you want to become a patron and jump on
2:57
our website and get all the details and the
3:00
platforms are Patreon or Supercast or
3:02
Spreaker or Apple Podcasts. They all do their
3:05
own versions of patron, uh, services.
3:08
So if you're interested in joining
3:10
Daryl, um, that would be greatly
3:13
appreciated, but it's not mandatory.
3:15
Okay. This one, uh, I suspect he's
3:18
right that we probably can't look back at the
3:21
birth of our sun. It's not as simple as
3:24
just finding it and going, oh, look at that.
3:26
That's, that's what was happening, you know,
3:28
all those billions of years ago. But um, we
3:30
can see a lot of stuff that's historical.
3:32
Just about everything actually.
3:35
Professor Fred Watson: Yep, that's right. You're as, ah, exactly as
3:37
Darrell says, when you look out into space,
3:39
you're always looking back in time. And
3:41
that's the trick. So, um,
3:44
we do indeed see The Andromeda Galaxy
3:47
2½ million years after the light
3:50
left. So we're looking back quite a long
3:53
time.
3:53
Andrew Dunkley: That's shortening slowly because ultimately.
3:57
Professor Fred Watson: That's right actually. Um, and as well, just
4:00
a quick um, plug for the
4:03
Andromeda Galaxy while we're talking. It's
4:05
um, very much in our skies at the moment. Uh,
4:08
uh, November is the time of year when
4:10
Andromeda is sort of at its highest. Uh,
4:13
it only skirts our northern horizon here in
4:16
Australia. But, but if you're in Europe or
4:19
the United States or elsewhere in the
4:21
Northern Hemisphere, it passes almost
4:22
overhead. Um, and in fact I was looking for
4:25
it a, uh, few nights ago from Cyprus. Um,
4:28
but the pair of binoculars that I
4:31
had weren't good enough to find it among the
4:34
light pollution of the place where I was
4:36
looking. So I didn't see it, but I kind of
4:38
knew where it was. I saw Saturn instead. Um,
4:41
never mind. Uh, that um, is,
4:44
uh, you know, that's what
4:47
happens when you're looking at something that
4:48
is so far away the light has taken two and a
4:50
half million years to get here. Um,
4:53
the problem with finding our sun being
4:56
born, uh, is that that
4:59
happened 4.5 exactly as Darrell
5:02
says, 4.5 billion years ago
5:04
and the sun is only 150 million
5:07
kilometers away. So we can never see the
5:10
sun, uh, uh, except at
5:13
any other stage, uh, than what it was eight
5:16
minutes ago. That's the look back Time for
5:18
the sun, it's about eight minutes. Um,
5:21
so when you see the sun, um, you're seeing it
5:23
as it was eight minutes ago, not four and a
5:25
half billion years ago. So really
5:28
the only way you could do this and it still
5:31
wouldn't really work. But if you could find a
5:33
way of putting a mirror, uh,
5:37
2.25 billion years
5:40
from us, looking back at us,
5:42
and you look in that mirror, then the
5:45
light from the sun being born will have gone
5:48
out to the mirror. Taken 2.25 billion years
5:51
to do that. It'll take another 2.25
5:53
billion years to get, uh, to now
5:57
when we're looking at it and we might see the
5:59
sun being born. But that is flight of
6:02
fancy, because it's never going to happen.
6:04
Andrew Dunkley: Even gravitational lensing probably couldn't
6:06
bend like that.
6:07
Professor Fred Watson: No, that's right. That's correct. You're
6:09
right.
6:11
Andrew Dunkley: Sorry, Darrell. Uh, probably not, but,
6:14
um, great question. And keep, uh, them
6:16
coming. Uh, but we are seeing and
6:19
learning so much from, uh,
6:22
historical light and uh, gravitational
6:25
lensing. And we even get to witness certain
6:27
things more than once because the light gets
6:29
split each two or three ways and we can
6:32
see something from different angles. It's
6:35
really quite, um, quite amazing what's going
6:38
on out there. And, um, to
6:40
quote, uh, Jonti, it makes my head hurt
6:43
sometimes to try and think of how this is all
6:45
working and why it's all happening.
6:48
Professor Fred Watson: Uh, yeah, that's right. Mine does all the
6:50
time. Um, but you reminded me something I
6:53
meant to mention, uh, because there is
6:56
a quirky thing. We can look back,
6:59
uh, at, uh, some events that took place in
7:01
the historical. And what I'm thinking of is
7:04
light echoes. Uh, so, for example,
7:07
the supernova that was observed by
7:10
Tycho Brae, the Danish astronomer
7:13
in, um, I think it was
7:15
1572 when he observed that.
7:18
Uh, that has recently been observed again
7:21
because it lit up dust clouds,
7:24
uh, which give it a dogleg path.
7:27
Uh, so these dust clouds, ah, are sort of 400
7:30
light years away. And you get this dogleg
7:32
path and the light comes to us again with
7:35
that 400 year delay. And so we can
7:38
see what that supernova looked like because
7:40
the light is still traveling. And you can
7:43
analyze that with modern instruments and find
7:44
out what sort of supernova it was. I think we
7:46
covered that in space notes quite a while
7:48
ago, but it's great. Light echoes, uh, are
7:50
terrific things.
7:51
Andrew Dunkley: Yes, indeed. Thanks for your question, Daryl.
7:57
Generic: Three, two, one.
8:00
Andrew Dunkley: Space nuts. This one comes from
8:02
Rennie. Knowing the pace at which technology
8:05
builds on itself do you think we will have
8:07
solved the mysteries of what was before the
8:10
Big Bang, Dark matter, dark energy and
8:13
the expansion of the universe, let's say,
8:14
within the next 100 years. Uh,
8:17
Rennie's from California, uh, uh, and a
8:20
regular contributor. Thank you, Rennie. Um,
8:22
I, I suspect we'll have solved maybe one or
8:25
two of those things, uh, even while you
8:28
were away. Uh, and maybe just before you
8:31
went, they were starting to sort of waver on
8:34
the expansion of the universe theory. They
8:36
were starting to think, well, no, we're.
8:38
We're probably now looking at a gnab gib.
8:42
Um, so that. That's
8:45
now starting to change. Um,
8:47
the evidence is. Is, um, mounting up
8:50
to, um, change the probability
8:53
in that regard. So, yeah, um, 100
8:56
years is a long time in terms of, um,
8:59
science and astronomy development.
9:03
Professor Fred Watson: Yes, it is, at the rate technology is
9:05
changing now. Absolutely. And I think Rennie
9:08
asks a really good question. You know, it,
9:10
um, behoves us from time to time to stop and
9:12
think, well, what we're going to find out
9:14
next. Um, the expansion of the
9:17
universe. Yes, you're right. The, the most
9:19
recent observations, uh, seem to
9:22
suggest that the acceleration of
9:25
the expansion is slowing down. And if the
9:28
acceleration slows down enough, then
9:31
it might well start to decelerate. And so,
9:34
yes, perhaps one day, um, I've forgotten how
9:36
many billion years into the future it is.
9:38
It's 40 or 50, I think, uh, we might have a
9:40
gnab. Gib. A big crunch when everything falls
9:43
back together. So you're right. That's a, uh,
9:46
thing that this is discoveries, or what you
9:48
might call facts about the universe that are
9:50
constantly being updated. Um,
9:54
what was before the Big Bang? That's always
9:56
an open question because, um,
9:59
the general theory of relativity suggests
10:02
that time started with the Big Bang. And
10:04
so before might not have any meaning.
10:07
Uh, but there are people thinking, well,
10:10
maybe that's not correct. Uh, we've talked
10:13
about, you know, explosive, um, um,
10:16
phenomena in a kind of continuum.
10:19
Things like gigantic black holes
10:22
exploding. And if we're in one of them, that
10:25
might be what we see as a Big Bang. Even
10:27
though that black hole was in space, that
10:28
existed already. This is another idea, uh,
10:31
that I think we talked about a few months
10:33
ago, Andrew. So, um, that's, um, you
10:36
know, how you find the evidence for all those
10:38
things is the important bit. And at the
10:40
moment, our perhaps most powerful
10:43
tools are the cosmic microwave background
10:45
radiation, the flash of the Big Bang, which
10:47
is still being analyzed, um, and
10:50
gravitational wave telescopes, which might
10:52
lead us to some inferences about
10:55
the dynamics of the Big Bang, the way
10:57
material shifted around. Um,
11:00
so ah, that's one I think uh, we'll
11:03
see a lot more uh, emphasis and we might have
11:06
new discoveries about it. Dark matter I hope
11:09
will, we'll get to the bottom of that within
11:12
uh, maybe the next 10 years rather than the
11:15
next hundred years. But um, it's a
11:17
problem that's existed for 90 years
11:21
since Fritz Vicki first spotted it. So it
11:24
might still have another 90 years to go. I
11:26
don't know. Dark energy, um,
11:29
that it really feeds into the, or uh,
11:32
our understanding of dark energy uh, is
11:34
basically tied up with our understanding of
11:36
the way the acceleration of the universe is
11:39
changing. Because if you've, if the
11:42
acceleration is actually decreasing as we
11:45
now think it might be, then dark energy is
11:47
not what we used to call the cosmological
11:49
constant. It's not a constant, um,
11:52
phenomenon. It's something that evolves with
11:54
time and that becomes even more mysterious.
11:57
So I think of all those, dark energy is the
11:59
one that's going to take us the longest to
12:01
work out. But I Hope it's not 100 years
12:03
because I won't be around in 100 years time
12:05
even with the best will in the world.
12:07
Andrew Dunkley: Yeah, yeah, I know, um,
12:10
but you know,
12:13
where technology's going, it's just going
12:16
ahead in leaps and bounds how quickly
12:18
artificial intelligence is taken off.
12:20
Professor Fred Watson: That's right, yeah.
12:21
Andrew Dunkley: What uh, are we going to be able to do in 100
12:23
years with telescopes? And uh,
12:26
there'll probably be uh, telescopes
12:29
uh, on the moon and Mars and maybe on a few
12:32
of the other moons in other parts of the
12:34
solar system. Um, you
12:37
know there'll be more space telescopes than
12:39
you can poke a stick at I imagine. And, and
12:41
very, very high tech compared to what we can
12:43
achieve now, which is really high tech in
12:45
itself.
12:47
Professor Fred Watson: Yeah, um, space telescopes um,
12:49
are things ah, that are not that prolific
12:52
because they're expensive compared with
12:54
ground based telescopes and astronomy doesn't
12:57
really have budgets that are huge, um, you
13:00
know, compared with something like defense or
13:03
education or all of those other publicly
13:05
funded things. So astronomy tends to be very
13:08
much picking up the pieces. And something
13:10
like the James Webb telescope is an
13:12
exception. Uh, that uh, is
13:15
revolutionary. But it's true that there are
13:18
other space telescopes coming on stream. The
13:20
Grace Roman telescope which will be
13:23
launched I think within the next year,
13:25
probably sooner I hope.
13:27
Andrew Dunkley: Uh, I looked up a while back that
13:30
there are 27 or something in the
13:32
pipeline.
13:33
Professor Fred Watson: In the pipeline, yeah. Not all of those will
13:35
be funded though. And you know, so that when
13:38
you think like the James Webb telescope
13:42
came and got into action, what, 20, 22,
13:45
is that right? Um, something like that.
13:47
Thereabouts. Um, the last big thing in
13:50
optical astronomy and in uh, infrared
13:52
astronomy was the Hubble telescope launched
13:54
in 1990. So, you know, that's
13:57
like 30 years interlude. But
14:00
yeah, you're right. Um, as time goes on, I
14:02
mean, one of the things that is changing that
14:05
will actually affect this is that it's now
14:08
much cheaper to put stuff into orbit than it
14:10
was, uh, partly because of
14:12
SpaceX being able to reuse its Falcon
14:14
boosters. Um, the latest record is one
14:17
that has flown 31 times, uh, which
14:20
is quite extraordinary. But also we've now
14:22
got Blue Origin coming into the picture with
14:24
their successful recovery of their new new
14:27
Glen booster a couple of weeks ago, which is
14:29
fantastic. So things are changing.
14:31
Andrew Dunkley: Yes, indeed. Thanks Rennie. Great to hear
14:34
from you. This is Space Nuts with Andrew
14:36
Dunkley and Professor Fred Watson.
14:42
Professor Fred Watson: Space Nuts.
14:43
Andrew Dunkley: Okay, next question. Hey guys. Greetings from
14:46
Dave. He's from Sussex county in New Jersey.
14:49
I have a pretty quick question in 25
14:51
parts. Uh, suppose, no,
14:54
suppose that a Jupiter size or sub
14:57
brown dwarf planet, um, has a
15:00
moon the size of Earth. Would the moon
15:02
necessarily be tidally locked to the planet?
15:05
Also, would it be possible for the Earth
15:08
sized satellite to be in the Goldilocks
15:10
zone of the super Jupiter? Love listening to
15:13
your podcasts. It's good stuff. Thanks
15:16
Dave, appreciate it.
15:19
I like this question because, um, when you're
15:22
talking gas giants, sub brown
15:25
dwarfs, um, failed stars, whatever you like,
15:28
um, you're getting into some pretty exciting
15:30
territory.
15:33
Professor Fred Watson: Uh, you are indeed. That's right. Um,
15:36
so super Jupiters, things bigger than
15:38
Jupiter, uh, and um,
15:42
exactly as Dave says, that would be a sub
15:45
brown dwarf. Um, I've got to get my
15:48
thinking right here. I think brown dwarf, um,
15:52
probably. I hope I don't get this number
15:54
wrong, but I think it has to be more than
15:57
13 times the Mass of Jupiter, uh, for
16:00
the low level nuclear reactions that will
16:03
power it and turn it into a brown dwarf, uh,
16:05
to actually make much difference to it, to
16:08
mean that it radiates in the infrared region
16:11
of the spectrum. In a sense, Jupiter itself
16:13
is a sub brown dwarf because it actually,
16:16
uh, radiates, I think it's 50% more
16:19
radiation than it receives, um, from
16:22
the sun. So there are nuclear processes
16:24
taking place deep in Jupiter that actually
16:26
give off energy. Um, and so
16:29
something like, you know, if you have
16:31
something, let's say halfway between a brown
16:34
dwarf and a Jupiter and it's got a moon the
16:37
size of the Earth. That's the scenario that
16:39
Dave's postulating. Would the moon
16:41
necessarily be tied, locked to the planet? In
16:43
other words, would that moon, the Earth sized
16:45
object, uh, be um,
16:48
one that always faced its parent
16:50
planet? I think the answer to that is yes.
16:53
Uh, because it's all about mass, this whole
16:55
gravitational locking of uh,
16:59
um, moons, uh, around planets or
17:02
indeed planets around their parent star.
17:03
Because the same thing happens, it's all
17:05
about gravity. Uh, and if you've got um, you
17:08
know, two objects that are bigger than the
17:11
ones that we think of at the moment, uh, then
17:13
I think you would still get the tidal
17:15
locking. So my guess is that your moon, your
17:18
Earth sized moon would be uh,
17:21
tidally locked. In other words, it would
17:23
always face the sub brown dwarf.
17:26
And then, uh, would it be possible for the
17:28
Earth, uh, sized satellite to be in the
17:30
Goldilocks zone of the super Jupiter? Uh,
17:33
so that depends on what just how
17:35
much energy you're getting from it. I mean
17:38
the, the Goldilocks zone of a brown dwarf is
17:40
much closer uh, to the brown dwarf
17:43
than it is for a normal star. Uh, and
17:46
maybe uh, you don't, you can't get near
17:49
enough. That might be the answer to that
17:51
question. That the Goldilocks zone is so
17:53
close to the super Jupiter, uh, that it
17:56
really is, you know, it's not something
17:58
that's at all practical, uh, I'm guessing at
18:01
that. And some planetary specialists might
18:04
correct me, but I think that would be the
18:05
case that you're going to find the Goldilocks
18:08
zone of a super Jupiter. Uh, that's going to
18:10
be very helpful, um, uh,
18:13
for life on an Earth sized satellite of
18:16
such a star. Um, work
18:19
that one out for yourself.
18:21
Andrew Dunkley: Yeah, you were right though. Thirteen, um,
18:24
masses.
18:25
Professor Fred Watson: Okay, good.
18:26
Andrew Dunkley: Uh, when you get to, sorry, I put my hands in
18:28
front of the camera there, uh, 13 to 80
18:31
Jupiter masses is defined as a brown
18:34
dwarf. And then beyond
18:36
that is a star I guess because it can
18:39
burn hydrogen or something. Is that it?
18:41
Professor Fred Watson: That's right.
18:42
Andrew Dunkley: Yeah, yeah, yeah, yes. So yeah,
18:45
under 13 is um, is,
18:48
is basically just a gas giant.
18:51
Professor Fred Watson: Indeed. That's right, yes.
18:52
Andrew Dunkley: Right.
18:54
Professor Fred Watson: Or a sub brown.
18:54
Andrew Dunkley: Or a sub brown dwarf.
18:56
Professor Fred Watson: Yes. Yeah.
18:57
Andrew Dunkley: It's just hard to. Yeah.
19:01
Um, so yeah, the tidal locking
19:04
question definitely, probably would,
19:06
probably, definitely would happen that way.
19:09
I think so as Dave said. Great, um,
19:11
question. Thank you for sending it in, Dave.
19:16
Generic: Three, two, one.
19:19
Andrew Dunkley: Space Nuts.
19:21
Our final question today comes from
19:24
Cal. Hi Space Nuts. I was uh, wondering if a
19:27
gas giant orbiting a star
19:30
that went supernova can then subsequently
19:33
absorb the debris from that star at the end
19:36
of its life to form enough mass to then
19:38
form itself into a star.
19:42
And the second part of my question
19:45
is, uh, if not, can a gas
19:47
giant have enough mass and gravity for, uh,
19:50
other smaller planets to end up orbiting the
19:53
gas giant with no star? Is there
19:56
any example, uh, or evidence of this ever
19:58
happening out there? Thank you so much. Cal
20:00
from Swansea, uh, Swansea, South Wales in
20:03
the, um, Lake Macquarie region of
20:06
New South Wales, just, uh, across near
20:09
coast from us. I drove through there the
20:10
other day actually.
20:13
Professor Fred Watson: Yes.
20:14
Andrew Dunkley: Uh, so, um, what was it? What's he want to
20:16
know? Gas giant. Um, a
20:19
gas giant orbiting a star that goes
20:20
supernova. Could it absorb enough energy to
20:23
become a star itself? First part of his
20:26
question.
20:26
Professor Fred Watson: Um, so when an object
20:29
turns into a supernova, it basically
20:32
blasts debris, a very high
20:35
velocity, uh, into the surrounding
20:38
region of space. Um, and it's
20:41
not even clear that a gas giant would survive
20:43
that, let alone accrete
20:45
debris to form a star itself. So I
20:48
think the answer to that first part of the
20:50
question is no. Um, uh, if,
20:54
you know, if you've got, uh, this gas
20:57
giant orbiting a star that goes supernova,
21:00
I don't think it would end up a star itself.
21:02
It might even end up being destroyed
21:05
by the shockwaves that come from the
21:07
supernova. Um, on the other hand, we do
21:10
have one example of a planet orbiting
21:12
something that has gone supernova. And, um,
21:15
that was the first, um, extra solar
21:18
planet that was discovered back in the 1950s,
21:20
70s. I think there's
21:23
something called the double pulsar.
21:26
I think I'm right in digging that up from my
21:29
memory. Anyway, second part of the question,
21:31
if not, can a gas giant have enough mass and
21:33
gravity for the other smaller planets to end
21:35
up orbiting it with no star?
21:37
Um, so perhaps what
21:40
you're thinking of here is one of
21:43
these objects that we call a rogue planet or
21:45
an orphan planet, something that is going
21:46
through space with no star. Uh, and
21:49
many of them are gas giants. Right. There
21:52
might be what we could call failed stars and
21:55
probably, uh, they have their own M moons
21:57
which might in some circumstances be
22:00
the size of smaller planets. Uh, we
22:03
haven't observed any moons of rogue planets
22:06
or orphan planets yet. But, um, it's
22:09
possible they might be there. Uh, so
22:11
the last bit of the question, is there any
22:13
example or evidence of this ever happening
22:15
out there? Um, I don't think there is, but I
22:18
wouldn't rule it out. It might well turn up
22:20
that we see, uh, objects in
22:22
orbit around rogue planets when We've got,
22:25
um, well, probably the next generation of,
22:28
uh, big telescopes.
22:30
Andrew Dunkley: Yes, indeed. Uh, when it comes to astronomy,
22:33
it's very difficult to rule anything out a
22:35
lot of the time because, uh, the
22:38
more exoplanets we discover, the more
22:40
unusual things we tend to find.
22:43
Like those cotton canned
22:46
planets.
22:47
Professor Fred Watson: Yeah, that's right. Fluffy ones.
22:50
Andrew Dunkley: Um, really huge planets that have got
22:53
next to no density at all. In some respects
22:55
they're just like vapor,
22:58
um, for want of a better term. And there
23:01
probably is a better term for that. But
23:04
we're finding, uh, and Jonti and I talked
23:07
about this recently, and you and I have
23:08
talked about this, that our solar system
23:11
starting to look like it is not typical
23:14
when we look at other solar systems and how
23:17
they've formed and how gas giants seem to be
23:19
on the interior rather than the exterior.
23:21
Ours seems to have kind of flipped and
23:24
doesn't look normal at all. We're
23:27
unique, possibly, I would think, in
23:30
the scheme of things, we wouldn't be. But,
23:31
um, it's just looking that way.
23:33
Professor Fred Watson: But certainly you're absolutely right. We
23:35
look very unusual. We look a bit conspicuous,
23:38
really.
23:38
Andrew Dunkley: Yeah. And we've got one other thing that's
23:40
really weird that no other solar system's
23:42
shown us that they've got yet. We've got a
23:44
planet with life,
23:47
an abundance of life in a great many forms,
23:50
from cnidal cells right up to complex life
23:53
forms, um,
23:56
plant life. Um, the
23:58
list is long.
24:01
When you really think about it, this planet
24:03
is miraculous with
24:06
what it contains.
24:09
Professor Fred Watson: Well, that's right. And that's one of the
24:12
reasons why, um,
24:15
you know, why there is such an emphasis on
24:19
detecting other Earth like
24:21
environments to see whether the same sort of
24:24
miraculous array of living organisms
24:27
can exist there. And so far we've drawn a
24:29
blank.
24:30
Andrew Dunkley: No, the Drake equation remains at one.
24:33
Professor Fred Watson: Yes, it does. That's right.
24:35
Andrew Dunkley: Would, um, finding life
24:37
on one of the ice moons in our solar system,
24:41
um, like Enceladus changed the Drake
24:43
equation? No, no, because it was based on
24:47
life that is capable of communication, wasn't
24:50
it?
24:50
Professor Fred Watson: That's right, it is, yeah.
24:51
Andrew Dunkley: Yeah.
24:51
Professor Fred Watson: It's basically life on, um, planets around
24:53
other stars. That's right, yeah. So
24:56
Drake equations set up. So no change to that.
24:59
Andrew Dunkley: Indeed.
25:00
All right, uh, Cal, thanks for the question.
25:03
Very, uh, very interesting and thought, uh,
25:06
provoking and, um. Yeah. Oh, that's right.
25:08
There was a question that came to my mind
25:10
from Cal's question. Um,
25:13
how big a, uh, radius
25:16
when a, um, star goes supernova? Are we
25:18
talking in terms of devastation?
25:23
Professor Fred Watson: Uh, you're talking about light years, um,
25:25
because the shock wave, um,
25:28
you know, when you think of like Supernova
25:31
1987A, which is one of the best studied of
25:33
all supernovae, it was in the Large
25:35
Magellanic Cloud, so relatively nearby, 100
25:38
meters, whatever. Is it 130,000
25:40
light years away? Something like that,
25:43
yes. My numbers are all a bit rusty because
25:46
of jet lag, but it's something like that.
25:48
Maybe 160,000. Anyway, never mind that it's a
25:51
long way off, uh, and it's very well studied
25:53
and you can already see the, you know,
25:56
the fact that, um, this high energy
25:59
radiation gone through a large, large
26:02
neighborhood around it, measured in light
26:04
years, which of course is much bigger than
26:06
the solar system. So that's the area of
26:09
devastation. Yeah.
26:10
Andrew Dunkley: So a, uh, planet sort of orbiting a star like
26:13
that probably wouldn't have a prayer, would
26:14
it? Yeah.
26:15
Professor Fred Watson: Yep, that's right.
26:18
Andrew Dunkley: Thank you, Cal. Enjoyed, uh, that question
26:20
very much. And if you've got a question for
26:22
us, please send it in. You can do that
26:24
through the Space nuts website, uh,
26:26
spacenutspodcast.com spacenuts IO
26:29
click on the AMA M link at the top and you
26:31
can send, uh, text or audio questions. Easy,
26:34
uh, to send an audio question because if
26:36
you've got a device with a microphone, like,
26:38
I don't know, a smartphone or a
26:41
tablet or a computer, they've all got them
26:42
these days. Just, um, press and talk and
26:45
uh, don't forget, forget to tell us who you
26:47
are and where you're from. We're all done,
26:49
Fred. Thank you.
26:51
Professor Fred Watson: Great pleasure, Andrew, good to chat and
26:53
great to get our listeners questions again.
26:55
There's some really intriguing thinking going
26:57
on there. Indeed.
26:59
Andrew Dunkley: Um, we'll catch up with you real soon.
27:00
Professor Fred Watson: See you, Fred. Sounds good.
27:01
Andrew Dunkley: Thanks a lot, Fred Watson, astronomer at
27:03
large. And uh, thanks to Huw in the studio
27:06
who, uh, couldn't be with us. We were just
27:08
talking about gas giants. Well, he's got a
27:10
giant gas problem
27:13
and he's had to go to hospital, but he'll be
27:15
back soon. And from me, Andrew Dunkley,
27:17
thanks for your company. We will see you on
27:19
the very next episode of Space Nuts. Until
27:21
then, bye bye. You'll be
27:24
listening to the Space Nuts podcast,
27:27
available available at Apple Podcasts,
27:30
Spotify, iHeartRadio or your
27:32
favorite podcast player. You can also stream
27:35
on demand@bytes.com.
27:37
Professor Fred Watson: This has been another quality podcast
27:39
production from bytes.com.