Latest / Space Nuts: Astronomy Insights & Cosmic Discoveries / Interstellar Insights: Comets, Cosmic Conferences & the Mysteries of Dark Energy

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Interstellar Insights: Comets, Cosmic Conferences & the Mysteries of Dark Energy · Space Nuts: Astronomy Insights & Cosmic Discoveries

0:00
Heidi Campo: And welcome back to another fantastic episode
0:03
of, uh, Space Nuts. This is the
0:05
podcast that is out of this world.
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Generic: 15 seconds. Guidance is internal.
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10, 9. Ignition
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sequence start. Space nuts. 5, 4, 3,
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2. 1. 2, 3, 4, 5, 5, 4,
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3, 2, 1. Space nuts. Astronauts
0:22
report. It feels good.
0:24
Heidi Campo: I'm your host for this episode, Heidi Campo,
0:26
filling in for our beloved Andrew Dunkley,
0:29
who is still, still on his cruise around the
0:31
world. He's been having a blast. And joining
0:34
me is professor Fred Watson,
0:36
astronomer at large. And Fred,
0:40
you have, um. You're traveling. You're in a
0:42
hotel. Tell us where you're at and what
0:44
you're doing.
0:44
Professor Fred Watson: Yeah, I'm at large. That's right. Um, so I'm
0:47
in the city of Adelaide, which is the, uh,
0:49
capital city of South Australia. That's a
0:51
state in the south of the country. As you
0:54
might expect from the name. The name tells it
0:56
like it is. Uh, and I'm here for the
0:58
annual meeting of the
1:01
Astronomical Society of Australia, which is
1:03
the body that, um, all professional
1:06
astronomers in Australia belong to. Ah, and
1:08
I think there's about 700 of us. There won't
1:11
be 700 here, but there's quite a
1:14
significant cohort. There was a reception
1:16
last night where I saw quite a few old
1:18
friends. So, um, that's why I'm here. I'm not
1:21
giving a talk as, ah, such, except
1:24
that on Wednesday, um, for
1:27
my sins, I'm the chair
1:30
of the steering committee of the, uh,
1:33
education and Public outreach chapter of the,
1:36
uh, of the society. Um, and they'll.
1:39
They're going to have a meeting which I'll
1:41
have to chair because I'm the chair of the
1:43
committee. Um, so I've put together a bit of
1:46
a presentation on what I think this chapter
1:48
should be concentrating on over the next 12
1:50
months. What the education and public
1:52
outreach section of the observatory should be
1:54
really, um, focusing their minds on. They
1:56
won't take any notice of me. Um, but that's
1:58
all right. It's just, you know, me doing my
2:01
bit for pushing, uh, education and public
2:04
outreach in the right direction here in
2:05
Australia.
2:06
Heidi Campo: Excellent. Well, that sounds like, uh, just
2:09
an absolute blast. I love that you're there
2:11
and you're going to be able to see old
2:12
friends. And I know what this means for us is
2:15
that we are going to have so many great
2:18
stories and updates after this conference.
2:20
Professor Fred Watson: Hope so.
2:20
Heidi Campo: You're going to be filling your brain with
2:23
all the latest and greatest and sharing it
2:25
with us. So that's really fun and
2:27
exciting, and we do have a lot of
2:30
really interesting Stories to talk about
2:32
today. Um, I don't have a fun
2:35
catchphrase. I think last week was histories,
2:38
mysteries and discoveries. And I don't have,
2:40
I don't have anything catchy today. We just
2:42
have some great stories.
2:44
But to kind of start it off, this is not
2:46
really a story, but a little bit more of an
2:48
announcement. Um, space shuttle is coming
2:51
back, apparently.
2:54
Professor Fred Watson: And it's coming to your city, uh, as
2:56
well, which is why I thought you'd like this
2:58
story, Heidi. Um, and it's part of the
3:01
big beautiful bill. Uh, apparently there is
3:04
in that bill $85 million to
3:07
move the space shuttle Discovery, uh, from
3:10
the Smithsonian Institution down
3:13
to Houston, uh, where
3:16
it's kind of going to live.
3:18
Uh, I don't know what the Smithsonian thinks
3:21
about this. I don't know whether they've been
3:23
asked. Uh, but that's the
3:26
idea that it's going to come back to Houston
3:28
and, um, uh, we'll see, uh,
3:31
what the outcome of that is. But I thought
3:33
you'd be exciting given that that's your home
3:35
city or excited given that that's your home
3:38
city.
3:38
Heidi Campo: Yes. Yeah. Well, and I really am. I
3:41
live just a couple minutes away
3:44
from Space Center. I chose our location
3:47
specifically because we wanted to live close
3:49
to all the action so I could jog there and go
3:51
see it. So that is kind of exciting. Um, I
3:54
really love, I love Space Center Houston, I
3:56
love Kennedy Space Center. All of these
3:58
places are such a
4:01
fantastic way to just, I mean, I
4:04
think every single one of our listeners who's
4:07
been to one of these places feels that
4:09
visceral pull of wow. That's when I really
4:11
started falling in love with space. So it's
4:14
exciting to have all of these things in one
4:16
place where they can be cared for and the
4:18
education can be there. And it's all space
4:20
related. So that's really kind of exciting.
4:24
But our first story today is one
4:26
that I am very curious about. I even
4:29
mentioned this to you before we started, um,
4:31
recording, but we have, it looks
4:34
like the third ever confirmed interstellar
4:37
object coming through our solar system, which
4:40
is so strange to me because I'm like, wait a
4:42
second, there's stuff coming, zipping around
4:44
all the time. So what is this third ever,
4:47
like, confirmed? And what is this object?
4:50
Tell us about this, friend.
4:51
Professor Fred Watson: Well, that's a great question, actually,
4:53
because nobody's really quite sure. Uh,
4:56
it looks like a comet. Uh, and comets
4:59
are different from asteroids in that they're
5:00
made principally of ice. And when the ice
5:03
gets near a star like the sun, uh, it starts
5:06
to turn into a gas, uh, to water vapor,
5:08
essentially bringing with it some of the
5:10
other chemicals that are, uh, um,
5:13
uh, embedded in the ice in the cold of space.
5:16
Uh, so. Yes, but you're also right that the
5:19
zipping around all the time around our
5:22
planet, uh, the material that we
5:25
sometimes regard as hazardous near Earth
5:27
objects, we're now concentrating on those
5:29
very heavily because we know that maybe one
5:31
day there will be an impact with the Earth,
5:33
and we need to do something about it. That's
5:35
a different story. This is certainly not in
5:37
that category. Um, but, uh,
5:40
yeah, there are three objects which are now
5:43
known to have come from outside the
5:46
solar system. Uh, and what tells you,
5:49
uh, that they've done that? And in the
5:51
particular case of this new object, which is
5:53
called 3i, which means it's the third
5:55
interstellar object atlas, which is,
5:58
um, an acronym for the name of the
6:01
facility that discovered it, which is down in
6:03
chile. Um, so 3i Atlas,
6:07
uh, has a velocity which is
6:10
something like
6:11
61,000
6:15
kilometers per second. Um,
6:17
and that's. Am I talking
6:20
rubbish here?
6:22
61km per second? I'm thinking
6:25
about kilometers per, uh, hour.
6:27
Heidi Campo: I had to check your math.
6:29
Professor Fred Watson: Yeah, that's right. It's about 60 kilometers
6:31
per second. Uh, whereas, um, things
6:34
that are, you know, part of the solar system,
6:36
and some of those, some of the comets that
6:39
whiz in from the Oort Cloud, this cloud
6:41
of debris that we think surrounds the solar
6:44
system, some of them achieve quite high
6:45
speeds, but it's never more than about 40
6:47
kilometers per second. Um, this
6:50
thing's 50% higher than that. And the other
6:53
clue that tells you that it's from outside
6:55
the solar system is the shape of its path
6:58
around the sun, the shape of its orbit. Uh,
7:01
because it's not an orbit that's closed in
7:03
the way we normally think of orbits. It's an
7:04
open orbit. Uh, it will only go past the
7:07
sun once. Um, you might be
7:10
familiar with the term eccentricity,
7:13
Heidi, which is the measure of the shape of
7:16
an orbit. Um, so if you've got an
7:19
orbit that's perfectly circular, it's got an
7:21
eccentricity of zero. Uh, anything
7:23
bigger than zero and less than one is an
7:26
ellipse. Uh, and the number, the
7:29
eccentricity number tells you how flattened
7:31
or how squashed the ellipse is, how elongated
7:33
it is. When you get to one, you've got a
7:35
parabolic orbit, one that just comes
7:38
in from infinity and heads off back to
7:41
infinity after it's gone past the Sun. This
7:43
one has an eccentricity of more than six.
7:46
And that's a huge number. And it tells you
7:49
that it's got to have come from outside the
7:51
solar system. Nothing inside the solar system
7:54
could have an eccentricity as high as that.
7:56
So it's all about the orbital details. Um,
7:59
it's uh, going to pass closest to the sun in
8:01
October, so we're still seeing it on its
8:03
inward path towards the Sun. Unlike,
8:07
um, the most famous, the first of the, uh,
8:09
interstellar objects that we discovered back
8:11
in 2017, oumuamua, a
8:14
Hawaiian word meaning first visitor from
8:16
afar. Um, because it was discovered in
8:18
Hawaii, uh, uh, on Haleakala in
8:21
fact. Um, uh, that one
8:24
was thought to be a few meters
8:27
across. Uh, it's really still not
8:30
certain what shape it was. It was thought to
8:32
be like a cigar at first, elongated shape.
8:34
But it's now perhaps thought to be more like
8:37
a dinner plate. But we didn't discover that
8:39
until it was actually on its way out of the
8:41
solar system. It was only seen after it
8:44
passed its closest to the sun. This one,
8:47
three, uh, I ATLAS is still on its way
8:49
in. And it's got a slightly
8:52
fuzzy appearance. And that tells you that it
8:54
is probably made of ice. And what it's doing
8:57
is actually releasing as it gets near the
9:00
Sun. The ice is. It's not melting, it's
9:03
subliming. Subliming means it's turning
9:04
straight from a solid to a gas, uh, and it's
9:07
releasing some of the d that's embedded in
9:09
the ice. And that's what's giving it that
9:11
fuzzy appearance at the moment. But it is
9:13
possible that we might start seeing
9:15
plasma ejected, which might tell us about
9:18
the constituents of its, uh,
9:21
icy core. Where did it come from? We don't
9:24
know. Um, there's some work being done that
9:27
suggests that, uh, our nearest star
9:29
system, Alpha Centauri, could in
9:32
fact, um, basically ejects
9:35
interstellar material, um,
9:38
around the whole vicinity of the sun,
9:41
not, not necessarily the direction that this
9:43
thing's come from. We don't know whether it's
9:45
come from Alpha Centauri or where it's, you
9:47
know, where it's come from. Um, but
9:50
it, uh, is certainly going to be the
9:54
subject of intense study. The world's
9:56
telescopes are already focused on it. I'm
9:58
sure the Webb telescope will get some time
10:00
looking at it and we might discover things
10:02
that we really don't have any other way of
10:05
finding out. You know, this is a sample
10:08
of material that has come from another solar
10:10
system. And so it could have quite different
10:13
physical characteristics, quite different
10:15
chemical makeup, uh, that's all the
10:18
sorts of questions that ah, are arising
10:20
about this object. So I'm sure that you and
10:23
I, or maybe you, maybe me
10:26
and that other. What's that other person
10:27
called? Oh, Dunkley. Yeah. Um,
10:30
maybe, maybe Andrew and I
10:33
might talk about it if you and I don't.
10:35
Because I think it will crop up again in the
10:38
news and certainly beyond space. And that's
10:40
horizon.
10:41
Heidi Campo: So what is the difference? At the risk of
10:43
sounding silly, I'll just ask this because
10:44
I'm sure someone else has this question too.
10:47
Something like Halley's Comet.
10:51
Is that not considered then, one of these
10:53
three objects?
10:55
Professor Fred Watson: No, no, that belongs to the solar system. Uh,
10:58
and that's because, uh, you know,
11:02
it actually is in orbit around the sun. It
11:04
has a period, an orbital period of 76 years,
11:07
if I remember rightly. Uh, which means it's
11:09
actually what's called a short period comet.
11:11
Anything less than 200 years I think is a
11:14
short period comet. Uh, but this thing is
11:16
different in the sense. And in fact all the
11:19
interstellar objects are different in that
11:21
they only go past the sun once and they've
11:23
got this very strange orbital path which,
11:26
uh.
11:26
Heidi Campo: Objects like Callisto, so it's never coming
11:29
back because it's one and done. Take a look
11:31
at it and it's gone.
11:32
Professor Fred Watson: That's right, exactly. And um, that's a
11:35
characteristic of, uh, things from other
11:38
solar systems. They whiz by and you think,
11:40
what was that? Um, but we're. Now,
11:42
the thing is, and there's an interesting,
11:45
um, postscript to this story which I should
11:48
mention. And that is we talked, uh, I think a
11:51
couple of weeks ago about the Vera Rubin
11:53
Observatory and the new telescope there that
11:55
is going to revolutionize our discovery, uh,
11:58
race of asteroids and things of that sort.
12:01
Uh, that's going to find far more of these
12:03
interstellar objects because it's so good at
12:06
discovering things that are moving, uh, you
12:08
know, through the solar system. Most of the
12:10
things it will discover belong to the solar
12:12
system. The asteroids that are in the
12:14
asteroid belt between the orbits of Mars and
12:16
Jupiter. And also the nearer ones, what we
12:19
call the near Earth objects. But, um, it will
12:21
find things that don't belong to the solar
12:23
system. And so we might go very quickly
12:26
from a sample of three interstellar objects
12:29
to, you know, tens or maybe even hundreds of
12:32
them that we are able to study.
12:34
Heidi Campo: Yeah, because it, uh, takes its samples every
12:36
three days, right?
12:37
Professor Fred Watson: Yeah, it does the whole sky every three days.
12:39
It's phenomenal. Yeah, it's incredible.
12:44
Generic: Roger, your lab is right Here also space
12:46
nuts.
12:47
Heidi Campo: Oh, we really are in such an incredible age
12:50
of discovery. Everyone, everyone who is alive
12:52
right now, I hope we recognize how
12:55
incredible it is to live during this time
12:57
because there's so much to discover and
13:00
there's so much for us to like. Every single
13:02
day we're learning so much more about the
13:04
universe. And that is, um, apparent with
13:07
our. With our next story with the New
13:09
Horizons conducting the first ever
13:11
successful deep space stellar
13:14
navigation test. That sounds like we're
13:17
really on the cusp of some exciting things.
13:20
Professor Fred Watson: Yeah, I think that's a great way to put it,
13:22
actually, um, because, uh,
13:26
it's a spacecraft that, um, you probably
13:28
remember it was launched in 2006, uh,
13:31
for, uh, an encounter with
13:34
the dwarf planet Pluto, which took place
13:37
in, if I remember rightly, it was July
13:39
2015, uh, when it flew by Pluto
13:42
and revealed what an astonishing Pluto is.
13:46
Uh, but since then it's been on its outward
13:49
journey. It flew by, uh, an object called
13:51
Arrokoth, uh, and gave us an impression
13:54
of that, probably images of that some
13:57
three or four years ago, I think now, and is
14:00
sort of on its way. It's one of the five
14:01
objects that will leave the solar system. Uh,
14:04
so they will head off to, you
14:07
know, the wide blue yonder. These objects
14:09
will almost certainly outlast
14:11
humankind and maybe even outlast our planet,
14:13
because there's nothing to stop them when
14:15
they head off that way. Anyway, New Horizons
14:18
was equipped, unlike the Voyagers and the
14:20
pioneers, which were products of the 1970s
14:23
and are still on their way out of the solar
14:25
system. New Horizons had some quite
14:27
sophisticated technology on board and in fact
14:29
includes effectively a telescope, um,
14:32
which can be used to measure the
14:35
positions of stars. That's a science
14:38
that we call astrometry, uh, the
14:41
measurement of star positions. And, uh,
14:44
um, that has actually been used now
14:47
to do, uh, as you said, a
14:50
navigation test, a stellar navigation test,
14:53
because it's so far from, uh,
14:56
our planet. Um, it's about
14:58
9.1, 9.1
15:01
9.2 billion
15:04
kilometers from Earth, uh, and
15:07
effectively from the sun, because our 150
15:09
million kilometers from the sun is a tiny
15:11
distance compared with 9 billion
15:14
kilometers. But it's so far from Earth,
15:16
uh, that it can now measure star
15:19
positions that are
15:21
significantly different from their
15:24
positions as measured from Earth. And by
15:26
significant, I mean, um, I don't mean
15:29
they're degrees away in the sky. They're, you
15:31
know, a few arc seconds away. Uh, that's a
15:34
small angle of 1,3600 of a
15:36
degree. Um, but they're different position,
15:39
they appear in different positions in the sky
15:41
than they do from Earth. And this is the
15:43
phenomenon that we call parallax. It's the
15:46
fact that if you look at objects from one
15:48
vantage point and then from another, they
15:51
appear at different angles and that is the
15:53
parallax angle. Uh, actually it's how
15:56
our eyes work as well. That our eyes, because
15:58
we have two eyes, they detect the parallax
16:00
between them, which gives us the 3D view of
16:02
the, of our environment. That still blows my
16:05
mind that our Brain can take two separate
16:08
images and make it into a 3D model of what
16:11
we're surrounding and what's surrounding it.
16:13
Fantastic stuff.
16:13
Heidi Campo: What I hate about that, and as soon as I say
16:16
it, all of our listeners are going to be so
16:18
mad at me. You usually don't notice your
16:21
nose.
16:21
Professor Fred Watson: Yeah.
16:22
Heidi Campo: Until you do. And then it's like, whoa, then
16:24
what is this thing? In my view,
16:27
it's like usually your brain kind of
16:29
overrides it. And then if you notice it, it's
16:32
like, whoa, it's right, it's right there on
16:33
my face.
16:33
Professor Fred Watson: It is, yeah. And when you get to a certain
16:36
age, there are hairs sprouting out of the end
16:37
of it that you find very annoying.
16:40
Heidi Campo: You see a whole new hair, you're talking to
16:42
somebody, you're like, wait a second, what is
16:44
that in my field of view?
16:46
Professor Fred Watson: But you're right. So you know, the nose
16:49
is very nearby. In fact, our brain, exactly
16:51
as you said, it kind of rules it out. Uh,
16:53
I've seen that before. I know what that is.
16:55
That's fine. But yeah, this three dimensional
16:57
model of, from stereoscopic vision
17:00
is effectively what New Horizons is doing.
17:03
It's giving us an eye on the Earth and an eye
17:05
9.5 or 9.3 or whatever it
17:08
is billion kilometers away. And that's big
17:11
enough to make an appreciable angle. And so
17:13
they've measured, uh, the distance using
17:16
this technique to two, uh, relatively
17:19
nearby stars. Proxima Centauri, which is part
17:21
of the Alpha Centauri system we were just
17:23
talking about a few minutes ago, 4.2 light
17:25
years from Earth. Um, and a star,
17:28
uh, called wolf, uh, 359. It's in a catalog
17:31
of stars by Herr Professor Wolf,
17:34
I guess. Um, that's about seven.
17:37
Nearly eight kilometers. Sorry, nearly eight
17:39
light years away. So these are nearby stars.
17:42
In fact, there are two nearest stars apart
17:45
from the Sun. Uh, and it's measured their
17:47
distances. And sure enough, the stellar
17:49
parallax gives you the right answer. So, um,
17:52
it's uh, yeah, we're. I think, uh,
17:55
the spacecraft is, uh, doing a fine job of
17:58
finding things to do while it journeys
18:00
through, uh,
18:03
well, it's approaching interstellar space.
18:04
It's still in the solar system. Still in the
18:06
outer reaches of the solar system, but
18:08
heading to interstellar space.
18:10
Heidi Campo: Oh, that's so cool. Uh, I just love.
18:13
I love learning all of this stuff.
18:18
Generic: 0G. And I feel fine. Space
18:20
Nuts.
18:21
Heidi Campo: Um, and our. And our. And our last
18:24
story of the day. This is the one that
18:27
everybody's gonna go crazy about. So
18:30
we. These are the questions that
18:32
we. I just think there's something that
18:35
humans are inherently fascinated by. We're
18:38
fascinated by the
18:41
things that we understand the least.
18:43
Sometimes the biggest mysteries attract
18:46
people the most. And that is. I would, if I
18:49
were to summarize the Space Nuts listeners.
18:51
This is what they get obsessed with.
18:53
So buckle up, everybody, because we are
18:55
talking about, uh, dark energy,
18:58
and we are talking about the story today. The
19:01
headline reads, if dark energy is decreasing,
19:05
is the Big Crunch back on the
19:07
menu? So if you have not heard what the
19:10
Big Crunch is before, Fred's going to give us
19:13
a recap, and then we're going to be talking
19:14
about how exciting this actually is.
19:18
Professor Fred Watson: Indeed. That's right. So, um, I mean,
19:21
it's almost like Back to the Future is this
19:23
because, um, when I was a young astronomer
19:26
back in the 70s and 80s,
19:28
uh, we were,
19:32
you know, we knew since 1929 that the
19:35
universe is expanding. That was Hubble's
19:38
discovery. Uh, and we
19:40
attribute that to some sort of event
19:43
that took place, we now think, about 13.8
19:46
billion years ago, which we call the Big
19:48
Bang, uh, because we can't think of a better
19:50
word for it. Uh, so
19:53
back in those days, um, we knew that
19:56
was the case, but astronomers were
19:58
fairly convinced, I think, that,
20:01
um, the expansion of the universe was slowing
20:04
down, even though they hadn't got the
20:06
measurements to prove that. They expected the
20:08
expansion of the universe to slow down
20:10
because of the gravitational pull of
20:12
everything in it, like galaxies and planets
20:14
and stars and podcasts. All of that
20:17
stuff's got gravity. Uh, and they expected
20:21
that would slow down the expansion of the
20:23
universe. And some, uh, astrophysicists.
20:26
Cosmologists really is the correct term.
20:28
They're the scientists who look at the
20:30
history and evolution of the universe as a
20:32
whole, uh, not just things in it.
20:36
Some cosmologists thought that the slowdown
20:38
might eventually result in a
20:41
switch over from an expanding universe to one
20:43
that's contracting because the gravity is
20:46
starting to pull everything back together.
20:48
Uh, and there was the
20:51
idea that perhaps at uh, some time
20:54
in the distant future there might be what
20:56
came to be known as the Big Crunch, uh, which
20:59
is everything smashing together again in a
21:01
kind of inverse of the Big Bang. It's the Big
21:03
Bang played backwards. And in fact, um, Brian
21:05
Schmidt m one of my colleagues, whose name
21:07
will crop up again in a very short time, uh,
21:09
he used to call it the Gnab Gibson, uh,
21:12
because it's the Big Bang backwards. So you
21:15
Big Bang backwards.
21:16
Heidi Campo: And that would kind of be like a rubber band
21:18
then.
21:19
Professor Fred Watson: Yeah, that's right. Yeah. The rubber band
21:21
expands and then, you know, if you let go, it
21:23
contracts. That's basically the mechanism for
21:25
that.
21:26
Heidi Campo: So, um, and then in theory, then would it be
21:29
exponentially? So it's like as it starts to
21:31
contract in, it starts to move faster as it
21:33
comes closer back to that main point.
21:36
Professor Fred Watson: That's exactly right. And it would be, you
21:38
know, you can imagine the Big Crunch or the
21:40
Nab Gib would be quite a
21:42
catastrophic event, um, for the
21:45
universe as a whole. It was thought to be
21:48
something that would happen billions of years
21:49
in the future. But that was all dashed
21:52
in, uh, 1998
21:55
when Brian Schmidt, uh, of the Australian
21:58
National University, uh, and Saul
22:00
Perlmutter in the United States, uh, they
22:03
led two teams that discovered
22:06
that the universe is not slowing down in
22:09
its expansion. It is actually accelerating.
22:12
Uh, and um, that
22:14
acceleration of the universe we attribute to
22:16
something called dark energy, which is one of
22:18
the biggest mysteries, uh, in the whole of
22:20
science. We don't know what it is, but in the
22:22
mass energy budget of the universe, it makes
22:25
up 70% or so of the
22:27
mass energy of the universe. So, um,
22:30
that sort of poured the cold
22:33
water on the Big Crunch idea,
22:36
uh, until now because
22:39
it looks as though from evidence coming
22:42
from a telescope, principally from a
22:44
telescope in Arizona, one very similar to our
22:46
Anglo Australian telescope here in, uh,
22:49
Australia. It looks as though the
22:52
acceleration is slowing down. So
22:55
yes, the universe is expanding. Yes, the
22:58
expansion is still getting faster and faster.
23:00
But it looks as though in
23:03
the future it won't be expanding as fast. In
23:06
other words, the, the acceleration itself is
23:09
slowing down and it's not a constant. And
23:12
that means that dark energy has different
23:14
properties from what we thought it had.
23:17
And that's what set off this chain of
23:20
research, uh, by uh, the
23:22
scientists, uh, whose work we're reporting on
23:25
now. They're um, uh, at Cornell University
23:28
and other, um, universities around the
23:31
world. They've looked at the,
23:34
the data that's come from various
23:36
telescopes, uh, and have Actually
23:39
made a model of a
23:42
universe that has an accelerated
23:45
expansion. The acceleration slows down.
23:47
Eventually the expansion slows down
23:50
and stops, and so
23:53
there's a collapse back on itself. And
23:55
they've modeled that to give you a universe
23:58
which has a lifetime of 33.8
24:01
billion years. Now, we're already
24:03
13.8 billion years into that, so
24:06
about 20 billion years time. They
24:08
are suggesting that there will be a Big
24:11
Crunch or a gnab gib. Um, and
24:14
it comes not just from modeling the
24:16
astrophysics. They've also looked at some of
24:18
the likely subatomic particles that
24:21
we might attribute dark energy to.
24:24
Uh, so, uh, it's, you know, this is very,
24:26
very speculative research, it has to be said.
24:29
Uh, and nobody, uh, really is
24:32
yet starting to think serious, seriously
24:34
about a Big Crunch, because that, as I said,
24:36
got wiped back in the 1990s. But
24:39
it could still be on the menu, exactly as
24:41
that headline, uh, says. It could still be on
24:44
the menu. And I'm sure as time goes on,
24:47
uh, our understanding of just how the
24:50
acceleration of the universe is behaving,
24:52
because it's still a difficult
24:55
observation to make whether the acceleration
24:57
is speeding up or not. Uh, but once we've got
24:59
more data on that, maybe models like this
25:02
will have their feet more firmly on the
25:04
ground and we might get some more
25:07
insights into what the future of the universe
25:10
is in the next 20 billion years or
25:12
so. By then, by the way, uh, the Earth won't
25:15
exist anymore because the sun will have
25:18
turned into a red giant star long before that
25:21
and probably melt the Earth. Uh, which is an
25:24
interesting idea. Um, that's only, you
25:27
know, that's on our near Horizon. That's only
25:28
3 or 4 billion years down the track. Uh, and
25:31
of course, the Andromeda and the Milky Way
25:33
will have collided. All of that will have
25:35
happened. But maybe the ultimate end is 20
25:38
billion years hence, and it could be another
25:40
Big Crunch.
25:42
Heidi Campo: Well, who knows what humanity will figure out
25:45
by then? I am convinced
25:48
that we can continue to become
25:50
masters of our planet, our solar
25:53
system. What is it called? Is it the Krasnow
25:56
Scale? The Kardashians? The
25:58
Kardashev.
25:59
Professor Fred Watson: That's right. It's, uh, Kardashev. I
26:02
think it is Kardashev.
26:04
Heidi Campo: Yeah, the Kardashev scale. And we are. They
26:06
mathematically figured it out because there's
26:08
three. I'm kind of. I'm, um,
26:11
I'm talking, um, about things that I'm not
26:13
quite confident on. But I believe there's
26:15
three different levels of civilization,
26:18
and they've mathematically figured out that
26:20
we're not Quite a level one civilization yet.
26:23
What are we, like a 0.7?
26:24
Professor Fred Watson: Like we're close.
26:25
Heidi Campo: We're almost there.
26:26
Professor Fred Watson: It's based on the, um, energy consumption,
26:29
uh, that Kardashev scale. It's based on how
26:32
much energy a, uh, civilization uses.
26:35
Uh, and that's a measure of how advanced it
26:37
is. Um, now it
26:40
needn't necessarily follow, I guess, because
26:43
we might discover new ways of living that
26:45
don't need the huge energy demands that the
26:48
Kardashev's scale thinks we will.
26:51
So, uh, interesting stuff, but yeah, we're
26:54
not, we're not quite there yet. You're right.
26:56
Heidi Campo: Yeah, yeah. I think it says that a type 1
26:59
civilization can harness the power from their
27:01
planet. A, uh, Type two civilization can
27:04
harness all the power from their solar
27:06
systems. We're talking about Dyson spheres
27:08
around the sun and then a type three
27:11
civilization. Um, I think they're masters
27:14
of space time so
27:17
they can travel.
27:18
Professor Fred Watson: Yeah, I think we should just skip straight
27:20
to, you know, Type three. We forget about the
27:22
others. I think type three is where we want
27:24
to be.
27:25
Heidi Campo: We need you. You're the brains. You're the
27:27
brains of this operation.
27:28
Professor Fred Watson: Well, you're in dire straits
27:31
then. Anyway. That's all
27:34
right. We'll um, you know,
27:37
becoming masters of space time is certainly
27:39
something that I have on my agenda, but I
27:41
haven't got anywhere near it yet.
27:44
Heidi Campo: Well, until then, we'll just have to stick
27:46
with the uh, sci fi literature out there to
27:48
fulfill that, to itch that scratch, so to
27:51
speak.
27:51
Professor Fred Watson: That's the one. Yeah, that's the way to do
27:53
it.
27:54
Heidi Campo: Well, excellent friend. This has been a
27:55
really fun conversation. Um, I really,
27:58
really enjoyed talking to you this, this dark
28:00
energy stuff. I know we're going to get a lot
28:02
of questions rolling in this week about it.
28:04
So if you guys ever do have questions on any
28:06
of these episodes, any of these topics, and
28:08
you are dying to have us follow up, please
28:11
just jump online. It's bitesz, bitesz dot
28:14
com, B, I, T, E, Z. And you can go to our
28:17
space nuts, portal and email us a question.
28:20
Ask us an audio question. We'll leave that
28:22
link for you. And you guys, please ask away
28:24
because we love to answer your questions
28:27
every other episode. We're talking straight
28:29
to you.
28:29
Professor Fred Watson: Sounds great.
28:32
Heidi Campo: All right everybody, we will see you next
28:34
time with a Q and A episode. Till then,
28:37
take care of.
28:38
Professor Fred Watson: Many thanks, Heidi. And you take care too.
28:42
Andrew Dunkley: Hello Huw in the studio. Hello Fred. Hello
28:45
Heidi. Hope you're all well. Andrew reporting
28:47
in from uh, the cruise ship
28:50
Crown Princess.
28:52
Uh, we are halfway through our world tour. I
28:54
can't believe the time has gone so fast. Uh,
28:57
since I spoke to you last, we have
28:59
visited Tenerife in the Canary Islands.
29:03
And Fred, uh, I know you will be
29:05
particularly be keen to um, uh to hear
29:08
that we drove past the uh,
29:11
TD Observatory. Uh, Mount
29:13
Teedi of course is the, the
29:16
strata volcano that's right in the middle of
29:19
Tenerife, uh, island. And it is one
29:21
imposing hunk of rock. That thing, it is
29:24
enormous. Uh, it just dominates the
29:26
skyline from everywhere you look.
29:29
Uh, but just across the caldera from
29:32
uh, Mount Teedy, which I might add hasn't
29:35
um, erupted since 1909. Didn't feel anything
29:38
while we were there, thank goodness. But um,
29:41
the TD Observatory and
29:43
that is uh, quite a remarkable uh,
29:46
little um, facility as you probably well
29:49
know Fred. It is because of the altitude.
29:52
It's up around 2,700 meters or something like
29:55
that. Uh, it uh, is, is a
29:58
solar observatory predominantly and uh,
30:00
it's one of the most significant solar
30:02
observatories in the world. But they also
30:05
do astronomical observations. And as
30:08
I understand it Fred, uh, this particular
30:11
observatory is
30:13
um, operated remotely. So I've got a
30:16
feeling that somewhere along the line Fred,
30:18
you have um, you've had a bit of a play
30:20
around with the equipment at Mount Teedi,
30:24
uh, on Tenerife. Uh, uh, I did take some
30:26
photos of the observatory from across the
30:28
valley and with my long range pocket
30:31
camera. Um, it's got several
30:34
uh, domes and pieces of equipment all
30:37
um, hidden inside white painted
30:40
buildings because they need to protect them
30:42
from the heat. And white is a uh, very
30:44
reflective color of course, but
30:48
uh, quite extraordinary. You climb up the
30:50
mountain on a very windy, steep road and
30:52
all of a sudden at around 2000 meters you
30:55
break through the tree line and
30:58
all of us and you're in what you could
31:00
describe as a tundra desert like environment.
31:04
And there have been so many eruptions over so
31:06
many millennia. There's all sorts of
31:09
different colored lava and pumice and layer
31:12
upon layer, uh, in the cliffs you can see
31:14
where the eruptions have happened, happened
31:16
over so many, many, many, many years.
31:19
And uh, the big 10 mile wide
31:21
caldera where there used to be a super
31:24
volcano which is uh, no longer there,
31:27
it collapsed and now you've got Mount
31:29
Tedi in its place which is uh, behaving
31:32
itself um, rather well at the moment, which
31:35
is good.
31:35
Anyway, we've left Tenerife behind us and
31:38
we're heading now for Morocco.
31:41
Uh, actually by the time I speak to you next,
31:43
we'll have made several stops. We've, uh,
31:45
we've reached the busy end of our tour, so,
31:47
uh, looking forward to telling you all about
31:49
that. Most of our visits between now and then
31:51
will be Morocco or Spain. Of course, Tenerife
31:54
is Spanish. Lovely, uh, lovely place.
31:57
Very, very popular with, uh, Germans and
31:59
English people, uh, on holidays. All right,
32:02
until next time, Andrew Dunkley signing off.
32:04
See ya.
32:05
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