Latest / Daniel and Kelly’s Extraordinary Universe / Listener Questions 16: pictures from space, antimatter stars and Jupiter-eating aliens!

Transcript

Listener Questions 16: pictures from space, antimatter stars and Jupiter-eating aliens! · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, Jorgey, I've got a space ethics dilemma for you.
0:12
Speaker 1: Oh I am definitely not qualified for that, but glad
0:16
Speaker 1: all right. So imagine that aliens come and they insist
0:19
Speaker 1: on destroying one planet in the Solar System, and they
0:22
Speaker 1: make you choose which planet are you going to sacrifice?
0:28
Speaker 1: That's not a dilemma, really, you already have a least
0:31
Speaker 1: favorite planet picked out. Oh yeah, I'm totally happy to
0:34
Speaker 1: lose Uranus. It does nothing for us except, you know,
0:37
Speaker 1: make things a little uncomfortable. Wow, I thought you were
0:40
Speaker 1: going to drop Pluto. But Pluto is not technically a planet,
0:43
Speaker 1: and I imagine the aliens are smart enough to know that.
0:46
Speaker 1: I guess there are benefits to being demoted from planetary status.
0:50
Speaker 1: Maybe it could be an oderb for them, or you know,
0:53
Speaker 1: just an upper teeth and the moves alien. Hi am
1:11
Speaker 1: or handy cartoonists and the creator of PhD comics. Hi.
1:14
Speaker 1: I'm Daniel. I'm a particle physicist, and I would never
1:18
Speaker 1: give up any planets in our Solar System. We are
1:20
Speaker 1: all one, really, you love them all. I just feel
1:24
Speaker 1: like it's a slippery slope, and you know, first you
1:26
Speaker 1: give up Ranus and then you go up Neptune. Then
1:28
Speaker 1: what are you going to say to protect Saturn in Jupiter?
1:31
Speaker 1: What about the asteroids? Do you feel fondly about the
1:34
Speaker 1: asteroids to We're all part of one gravitational disc man.
1:39
Speaker 1: I see, So if aliens came and wanted to eat
1:41
Speaker 1: something in our solar sysm, you'd be like, no, We're
1:43
Speaker 1: gonna fight eat to the death. I'd be like, can
1:45
Speaker 1: we just talk about it and you know, get some
1:47
Speaker 1: answers to physics questions first? There you know I would
1:50
Speaker 1: trade Saturn for some physics cancers. Oh really, so you
1:54
Speaker 1: would give up a planet to be eaten. I'm not
1:56
Speaker 1: giving up. I'm trading I'm getting something invaluable in turn
2:00
Speaker 1: for the human species. I see, what did they say,
2:02
Speaker 1: If we don't need lamp tune will eat Earth? Then
2:06
Speaker 1: you're you're trading something there. I don't negotiate with terrorists,
2:09
Speaker 1: even aliens, especially hungry aliens. But welcome to our podcast.
2:15
Speaker 1: Daniel and Jorge Explain the Universe, a production of I
2:18
Speaker 1: Heart Radio in which we imagine all of the crazy
2:21
Speaker 1: scenarios out there in the universe. We prepare you for
2:24
Speaker 1: crazy legal, ethical diallemmas, and we also prepare you for
2:28
Speaker 1: what we might learn about the universe. We take you
2:32
Speaker 1: on a ride to the very edge of scientific understanding,
2:35
Speaker 1: and we invite you to speculate, to ask questions, to
2:37
Speaker 1: think about what the answers might be to the biggest, deepest,
2:41
Speaker 1: most fun most consequential questions in the entire universe. That's
2:45
Speaker 1: right because there is a lot to discover out there,
2:48
Speaker 1: a lot of answers to find. It's a big universe,
2:51
Speaker 1: and we are here to talk about the answers and
2:54
Speaker 1: the questions. Would you that's right because those questions are
2:57
Speaker 1: really what drives science forward. Science wouldn't happen if, as
3:01
Speaker 1: a species, we weren't all collectively curious. If we all
3:04
Speaker 1: just really deeply and desperately want to know the answers
3:07
Speaker 1: to questions about how the universe started and where it's
3:10
Speaker 1: going and how it all works. It's not just scientists
3:13
Speaker 1: being curious. It's all of us. It's all of humanity
3:16
Speaker 1: collectively wondering about the nature of the universe. And that
3:20
Speaker 1: includes you. Yeah, because that is how our search for
3:23
Speaker 1: knowledge begins. It It starts with questions, right, Daniel, Physics
3:26
Speaker 1: doesn't start with statements. You're not big on statements. Physics
3:30
Speaker 1: usually starts with coffee. Actually, look at well, that's kind
3:33
Speaker 1: of a statement that caffeine is the most important kind
3:37
Speaker 1: of matter in the universe. No, it's a question which
3:39
Speaker 1: kind of coffee would you like today? No, but you're right,
3:41
Speaker 1: we do. We start with questions because science is all
3:44
Speaker 1: about those questions. It's about wondering how things work. It's
3:47
Speaker 1: about trying to unravel the greatest mystery in the history
3:50
Speaker 1: of humanity. Yeah, and sometimes, Daniel, you even have questions
3:54
Speaker 1: about your questions that you have nested questions or even
3:57
Speaker 1: question your questions like are these good questions? Is to
4:00
Speaker 1: ask why do we ask so many questions? Meta questions?
4:05
Speaker 1: And it's not just physicists and scientists who ask questions,
4:08
Speaker 1: it's everybody. It's an inherent part of being human to
4:11
Speaker 1: wonder about the universe, to think about and ask yourself
4:15
Speaker 1: how it all works. That's right, and that's what we're
4:17
Speaker 1: hoping to do with this podcast, not just to give
4:20
Speaker 1: you the answers to questions people are wondering about, but
4:22
Speaker 1: to inspire your questions, to get you to think about
4:25
Speaker 1: what it is that you want to know about the universe,
4:28
Speaker 1: because in the end, science is personal. It's not a
4:31
Speaker 1: big institution somewhere where everybody's wearing lab coats and eye protection.
4:35
Speaker 1: It's just people, people wondering about the universe, people just
4:39
Speaker 1: like you. Well, you actually wear eye protection was second
4:42
Speaker 1: to stop the high energy particles that might be coming
4:44
Speaker 1: at your face. I'm wearing eye protection right now to
4:47
Speaker 1: protect me from bad jokes that come across the audio.
4:51
Speaker 1: Nothing can protect you, Daniel. I got two or three
4:54
Speaker 1: pairs on right now. They're coming for you, dad. Joke
4:57
Speaker 1: proof eye protection, you were lead glasses with that help you?
5:00
Speaker 1: You've seen new three nos maybe, but you know they
5:02
Speaker 1: might not help you read. The best defense is a
5:04
Speaker 1: good offense and go after the power things. That's right,
5:08
Speaker 1: here's some antimatter of them. Maybe. But we do like questions,
5:11
Speaker 1: and we like to listen to questions from people like you,
5:14
Speaker 1: and sometimes in our podcast we like to feature these
5:17
Speaker 1: questions and try to answer them or at least talk
5:19
Speaker 1: about them live in front of an audience, like, for example,
5:22
Speaker 1: this great question we got from Hugo, who is five
5:25
Speaker 1: years old. Hello, my name is Hugo. How big the
5:30
Speaker 1: black hole has to be to suck me up? And? Oh,
5:36
Speaker 1: so great question? How big does a black hole need
5:41
Speaker 1: to be to suck you up. I feel like I
5:44
Speaker 1: wonder if he's concerned about that. I don't know. Yeah,
5:46
Speaker 1: do you think he's like planning a visit to black
5:48
Speaker 1: holes and he's wondering, like what size the black hole
5:51
Speaker 1: he should visit in order to be safe? And he's
5:54
Speaker 1: trying to get one as a pet, and he's wondering,
5:56
Speaker 1: like should I get a big one or a small one?
5:59
Speaker 1: What are the d us? Maybe he wants a black
6:01
Speaker 1: hole to suck up his sister and he's like, you know,
6:04
Speaker 1: really he's asking about that. Now, that is a mystery
6:06
Speaker 1: that would be make for an interesting novel there. But
6:10
Speaker 1: what's the answer, Daniel? How big does a black hole
6:12
Speaker 1: need to be to suck a small five year old child?
6:15
Speaker 1: There is no minimum size to a black hole that
6:18
Speaker 1: could eat Hugo. Like any black hole, no matter how small,
6:21
Speaker 1: would successfully eat up a five year old child. Really,
6:24
Speaker 1: even like a microscopic black hole would work. Even a
6:27
Speaker 1: microscopic black hole. The issues here are that really small
6:30
Speaker 1: black holes tend to evaporate because black holes evaporate more
6:34
Speaker 1: quickly as they get smaller, which is why, for example,
6:37
Speaker 1: we're not too worried about maybe making black holes at
6:39
Speaker 1: the large Hadron collider because they would evaporate really quickly.
6:43
Speaker 1: But if you made a really small black hole and
6:45
Speaker 1: you put it near a small child really quickly before
6:48
Speaker 1: it evaporated, it would eat parts of that child, and
6:50
Speaker 1: then it would grow and that would protect it. And
6:53
Speaker 1: so a very small black hole would grow quickly if
6:56
Speaker 1: you fed it, and it would get bigger and bigger
6:58
Speaker 1: and eat a child, and then that child sister, and
7:00
Speaker 1: then the entire apartment block and eventually even us. Oh
7:03
Speaker 1: man here, please please don't do it. So it wouldn't
7:06
Speaker 1: evaporate like faster than it could maybe absorb some of
7:09
Speaker 1: the mass from Hugo. It depends on how quickly you
7:12
Speaker 1: start feeding it. If you create the black hole and
7:14
Speaker 1: immediately start feeding it, it doesn't matter how small it is.
7:17
Speaker 1: It will just grow. If you create the black hole
7:19
Speaker 1: and leave it by itself for a little while before
7:21
Speaker 1: you feed it, then it might evaporate before you get
7:24
Speaker 1: back to it. See, don't you need to feed it
7:26
Speaker 1: at a faster rate than it's evaporating at. Yeah, you do.
7:29
Speaker 1: But you know, if you put it right next to
7:31
Speaker 1: a small child, it's gonna gobble that energy pretty quickly.
7:35
Speaker 1: Let's not imagine this scenario too much. It makes me
7:38
Speaker 1: a little uncomfortable. There might be some laws against this.
7:42
Speaker 1: But let's you say to Hugo that it's very unlikely
7:44
Speaker 1: you will ever visit a black hole, and if somebody
7:47
Speaker 1: is trying to sell you a black hole online, it's
7:49
Speaker 1: not a real one. So don't worry. That's right. And
7:51
Speaker 1: it's easier just to make up with your sister and
7:53
Speaker 1: you know, appreciate them because in later years they will
7:57
Speaker 1: be your best friends. That's right. You don't want your
7:59
Speaker 1: siblings to avo operate over to be eaten by a
8:01
Speaker 1: black hole or by anything I guess in general. But anyways,
8:05
Speaker 1: we love questions like this one from Hugo and so
8:07
Speaker 1: to be on the podcast will be tackling listener questions
8:16
Speaker 1: Number sixteen. This is our sixteenth episode in which we
8:21
Speaker 1: do and talk about listener questions. That's right, which means
8:24
Speaker 1: we're getting up on almost answering fifty of these things,
8:27
Speaker 1: which is pretty awesome. And I want to encourage anybody
8:30
Speaker 1: out there who has a question about the universe, something
8:32
Speaker 1: they'd like to hear us explain, or something they can't
8:35
Speaker 1: quite figure out just by googling to write to us
8:38
Speaker 1: with their questions two questions at Daniel ian Jorge dot com.
8:42
Speaker 1: We answer every email, we respond to every tweet. We
8:45
Speaker 1: might even put your question on the podcast. That's right,
8:47
Speaker 1: this is our Sweet sixteen episode. It's almost ready to drive.
8:50
Speaker 1: It can get a driver's permit, then what does it
8:53
Speaker 1: need us for anymore? Can just take itself around the
8:55
Speaker 1: country or pilot a spaceship? Maybe? Do they do? They
8:58
Speaker 1: give permits for that? Not it? But Amazon is selling
9:01
Speaker 1: them for a billion dollars each. I think, really, do
9:04
Speaker 1: you think to let you drive the spaceship if you
9:06
Speaker 1: pay a billion dollars? I think everything is for sale
9:08
Speaker 1: at Amazon or for a billion dollars. So yeah, So
9:12
Speaker 1: we have three amazing questions here from our listeners, and
9:15
Speaker 1: they have to do with space photography, about antimatter stars
9:18
Speaker 1: and what would happen if you ate a giant planet? Again?
9:23
Speaker 1: Do you think these are practical questions, Daniel, or maybe
9:25
Speaker 1: just born out of curiosity? I'm gonna go with born
9:28
Speaker 1: out of curiosity because I'm really hoping that there are
9:31
Speaker 1: no evil villains in their layers. They're typing out questions
9:34
Speaker 1: to us. I don't want to be a part of
9:36
Speaker 1: anybody's plans to eat Neptune or even to sell Jupiter
9:39
Speaker 1: to the aliens. You don't want to be a villain enabler.
9:43
Speaker 1: I do not want to be a scientist working for
9:45
Speaker 1: an evil villain, or a scientists working on some kind
9:48
Speaker 1: of particle collider then might create small black holes that,
9:51
Speaker 1: if put into contact with children, might be bad. Or
9:55
Speaker 1: a scientist helping a five year old child plot the
9:57
Speaker 1: demise of his sister. Let's focus on the positive here, absolutely.
10:03
Speaker 1: So we have three questions, and so do They will
10:05
Speaker 1: be tackling those, and we'll start with this one first
10:08
Speaker 1: from Simon from England, and he has a question about
10:12
Speaker 1: taking photos and speace. It's Simon from Nottingham, England. My
10:18
Speaker 1: question is one that's bothered me for some time. On Earth,
10:22
Speaker 1: of course, we can look at the sky at night
10:25
Speaker 1: and see starlight during a clear day, some particularly bright stars,
10:30
Speaker 1: these celestial bodies of Venus visitor the naked eye too,
10:36
Speaker 1: and also telescopes on Earth pick the stars up as well. Uh,
10:40
Speaker 1: and the incredible deep space images by by the whole telescope.
10:46
Speaker 1: But what I don't understand is how the critical footage
10:48
Speaker 1: captured joining the Apollo missions and later space missions don't
10:52
Speaker 1: show any starlight. Examples being Apollo eleven docking footage and
10:56
Speaker 1: the images of the Earth and the Moon. I'll just
10:58
Speaker 1: imagine that being in space without atmosphere, stars will be
11:01
Speaker 1: even brighter instead of inky blackness. Sure it was a
11:04
Speaker 1: simple answer, but I would love to know what that is.
11:09
Speaker 1: From you. Thank you. It's a brilliant loving every episode.
11:13
Speaker 1: Thank you, all right, thank you. Simon. His question is
11:17
Speaker 1: why don't we see stars in space pictures, and specifically
11:20
Speaker 1: he mentioned the ones from the Apollo mission to the Moon.
11:22
Speaker 1: Do you think he's maybe thinking there's a conspiracy going on.
11:25
Speaker 1: There's definitely a conspiracy theory about how people didn't actually
11:29
Speaker 1: land on the Moon and how these pictures were taken
11:32
Speaker 1: at a sound stage in Burbank. Of course that's all nonsense, right,
11:35
Speaker 1: It was in Hollywood, obviously, or Glendale. They do a
11:38
Speaker 1: lot of filming in Glendale. You can tell by the humidity.
11:42
Speaker 1: And one thing that people often quote when they say
11:44
Speaker 1: these ridiculous things is that you can't see any stars
11:48
Speaker 1: in the backgrounds of those pictures. And that's true when
11:51
Speaker 1: you look at these photographs of astronauts on the moon.
11:53
Speaker 1: You see the Moon, you see the astronauts, you can
11:54
Speaker 1: see the Earth sometimes in the background, but you don't
11:57
Speaker 1: see the stars out in space. I guess even today
12:00
Speaker 1: when they show pictures of the International Space Station or
12:03
Speaker 1: a picture of the Earth from space, like, you don't
12:06
Speaker 1: see the trillions and trillions of stars and we know
12:08
Speaker 1: are out there in space. I mean, technically we should
12:12
Speaker 1: see like the whole sky lit up with light from
12:14
Speaker 1: stars because there are, you know, bazillions of them. That's
12:17
Speaker 1: true for most photographs because of the way those photographs
12:21
Speaker 1: are taken, and we'll dig into that in a moment,
12:23
Speaker 1: But there are times that you can see the Earth
12:25
Speaker 1: in a field of stars, like the famous pale blue
12:27
Speaker 1: dot picture is a picture taken from Jupiter of the
12:31
Speaker 1: Earth and you can see the Earth is just one
12:33
Speaker 1: of many dots in that picture. Yeah, I guess you know,
12:36
Speaker 1: it makes sense when we're here on Earth, Like if
12:38
Speaker 1: we're here on Earth covered with an atmosphere which is
12:42
Speaker 1: blocking a level light, that would make sense why we
12:44
Speaker 1: wouldn't see the trillions of stars that are out there.
12:46
Speaker 1: But I guess this question is like if you're out
12:48
Speaker 1: in space going to the moon and you look out
12:50
Speaker 1: into space, why can't you just see all the maybe
12:54
Speaker 1: infinite number of stars that are out there. Yeah, And
12:56
Speaker 1: the answer doesn't really have to do with atmosphere. The
12:58
Speaker 1: atmosphere does absorb some light. It's not infinitely transparent, but
13:02
Speaker 1: that's not really an issue. That doesn't really stop us
13:04
Speaker 1: from seeing stars. And the reasons we have telescopes out
13:07
Speaker 1: in space, it's not because the atmosphere absorbs light. It's
13:10
Speaker 1: because it makes the pictures fuzzier. It just sort of
13:12
Speaker 1: like shuffles everything around, so we can get crisper pictures
13:16
Speaker 1: out in space then we can down here on Earth.
13:18
Speaker 1: The real issue is not one of the atmosphere. It's
13:21
Speaker 1: the issue of the sun. It's the issue of having
13:23
Speaker 1: other sources of light that are really really bright. Like
13:26
Speaker 1: you can see the stars just fine from down here
13:28
Speaker 1: on Earth as long as the Sun is not blinding you,
13:31
Speaker 1: long as the Sun is on the other side of
13:33
Speaker 1: the Earth. So you're saying, like, the reason I can't
13:35
Speaker 1: see more stars with my eyeballs, it's the sun. It's
13:38
Speaker 1: the sun. Like if you go outside right now and
13:40
Speaker 1: it's daytime and you look up at the sky, there
13:43
Speaker 1: are stars there. There are photons coming through space, through
13:46
Speaker 1: the atmosphere and hitting your eyeball from stars. You just
13:51
Speaker 1: can't see them because the sun is there and it's
13:53
Speaker 1: overwhelming everything. You know. It's like trying to hear a
13:58
Speaker 1: really quiet noise while you're at a super loud rock concert.
14:01
Speaker 1: You can't even tell that it's there. You're saying, the
14:04
Speaker 1: light actually is hitting my eyeballs, and maybe is hitting
14:07
Speaker 1: my you know, photoreceptors and and sensors in the back
14:10
Speaker 1: of my eyeball, but they're getting so much more light
14:13
Speaker 1: from the sun that basically doesn't register. Or maybe my
14:16
Speaker 1: eyes have calibrated not to notice these small things. Yeah, exactly.
14:19
Speaker 1: It's about the range and your eyes respond. During the day, right,
14:22
Speaker 1: if you look up at the sky and it's bright out,
14:24
Speaker 1: then your pupils will close a little bit. Right, the
14:26
Speaker 1: little hole in your eyeball that lets in the light
14:29
Speaker 1: will shrink because it's very bright and you don't want
14:31
Speaker 1: to damage the very sensitive stuff on the back of
14:33
Speaker 1: your eyeball. So during the day that shrinks, and so
14:36
Speaker 1: you're actually less sensitive to really dim objects. And then
14:39
Speaker 1: if you go into a dark room, it takes a
14:41
Speaker 1: little while over your eyes to adjust, they relax, and
14:43
Speaker 1: they open up and they let in basically every single photon.
14:47
Speaker 1: That's why you can see dimmer things at night because
14:49
Speaker 1: your eyes have opened up to let in more photons.
14:52
Speaker 1: So it is actually harder to see those stars during
14:55
Speaker 1: the day because your eyes are protecting you from the sun.
14:57
Speaker 1: If you looked up at the sky in the middle
15:00
Speaker 1: of the day with your eyes on like night vision mode,
15:03
Speaker 1: you could damage the back of your eyeballs. Yeah, don't
15:05
Speaker 1: look at the sun, people, please. This is not an
15:08
Speaker 1: experiment suggestion here. So it's all about relative intensity. Right.
15:12
Speaker 1: The stars are there, they're just very dim relatives to
15:15
Speaker 1: the other things you're seeing during the day, namely sunlight. Right,
15:18
Speaker 1: but what about during the night, Like, if I look
15:21
Speaker 1: up at the sky at night, why can't I see
15:24
Speaker 1: the trillions of stars that have been we know are
15:25
Speaker 1: out there. You can see the trillions of stars that
15:27
Speaker 1: we know are out there. You can see lots of stars.
15:29
Speaker 1: It depends a little bit on where you are. If
15:31
Speaker 1: you're near a city, then you're seeing a lot of
15:33
Speaker 1: light pollution that's washing out a lot of those stars.
15:36
Speaker 1: If you go to the very very dark woods or
15:39
Speaker 1: a place where they protect the night sky. Then you
15:41
Speaker 1: can see an incredible number of stars. It's really amazing.
15:45
Speaker 1: So for those of you who have always lived in
15:47
Speaker 1: the city and never been camping, find a way to
15:49
Speaker 1: go out into the woods at night and look up,
15:51
Speaker 1: and you can see an incredible number of stars. They
15:53
Speaker 1: really are out there. You just mostly don't see them, right.
15:56
Speaker 1: You just need a telescope and some bear scrape and
16:00
Speaker 1: if you want to see even more, you just need
16:01
Speaker 1: to accumulate more light. Like the more distant ones, the
16:05
Speaker 1: ones that are hardest to see, they are dim because
16:07
Speaker 1: they are not sending you as many photons per second
16:10
Speaker 1: right there further away, so fewer of their photons are
16:13
Speaker 1: coming to Earth. But if you set up a camera
16:16
Speaker 1: and you leave it out there for hours at a
16:17
Speaker 1: time so it can accumulate those photons, it can see
16:21
Speaker 1: things that you can't see with your eye because it
16:23
Speaker 1: can take like an eight hour exposure, and so then
16:26
Speaker 1: you can see incredible stuff. You can see Andromeda, the
16:28
Speaker 1: neighboring galaxy. You can see very very distant objects. Right.
16:32
Speaker 1: I think maybe that's the key to all of this
16:34
Speaker 1: and to this question, is this idea of aperture and
16:37
Speaker 1: like how much time your sensor is out there receiving photons.
16:41
Speaker 1: Because maybe something that people don't think about is that
16:44
Speaker 1: when something is dim, like a light is dim, it
16:46
Speaker 1: doesn't mean that the photons are somehow less powerful. It
16:49
Speaker 1: just means that they're less frequent. Right, that's right, because
16:52
Speaker 1: light is broken up into pieces, and every photon travels
16:55
Speaker 1: at the speed of light, and an object that is
16:58
Speaker 1: dim just means fewer photons per second, right, not less
17:01
Speaker 1: energy per photon. The energy per photon tells you the
17:04
Speaker 1: color the frequency of the photon. But if something is dim,
17:07
Speaker 1: it just means you're not getting as many photons. The
17:10
Speaker 1: way I think about it is like imagine some star
17:12
Speaker 1: out there. It's pumping out a huge number of photons
17:15
Speaker 1: every second, but as you get further and further away,
17:18
Speaker 1: you have a smaller and smaller slice of this big
17:21
Speaker 1: sphere that surrounds that star. So you get a smaller
17:24
Speaker 1: fraction of those photons. And the further way you are,
17:27
Speaker 1: the fewer photons are going to come and hit your eyeball.
17:30
Speaker 1: Mostly they're gonna go to the left or to the
17:31
Speaker 1: right of the earth. And so ye dimness comes from
17:34
Speaker 1: smaller number of photons, And so that's also the answer
17:38
Speaker 1: to what's going on with the pictures taken in space. Yeah,
17:41
Speaker 1: because the camera sort have worked like your eyeballs, right, Yeah,
17:44
Speaker 1: cameras work just like your eyeballs. And when you're in space,
17:47
Speaker 1: most of those photographs are basically the equivalent of taking
17:50
Speaker 1: a photograph during the daytime, because it's hard to hide
17:53
Speaker 1: from the sun in space, right. The Earth is not
17:56
Speaker 1: usually between you and space. So most of those photographs,
17:59
Speaker 1: like the ones in Apollo eleven, are taken when the
18:01
Speaker 1: sun is beaming down with its full brightness on the Moon,
18:05
Speaker 1: and so the stars are there, but you just can't
18:07
Speaker 1: see them the same way you can't see the stars
18:09
Speaker 1: when you take a picture in full sunlight here on Earth, right,
18:12
Speaker 1: because the film and the camera sort of adjusted to
18:15
Speaker 1: get the light from that's bouncing off the Moon. It's not,
18:18
Speaker 1: you know, a set up to kind of be sensitive
18:21
Speaker 1: to the light that's coming from the background in the stars. Yeah.
18:25
Speaker 1: And if you did that, if you open the aperture
18:26
Speaker 1: wide and took a long exposure, then you would be
18:29
Speaker 1: totally washed out by the sunlight. You just get a
18:31
Speaker 1: huge white blob, the same way you did if you
18:34
Speaker 1: took a picture here on Earth and you left your
18:36
Speaker 1: camera shutter open for too long, it would just get
18:38
Speaker 1: all washed out. If you're on the part of the
18:40
Speaker 1: Moon where the sun isn't shining right, then it would
18:42
Speaker 1: be dark, and you could take a night sky photograph
18:45
Speaker 1: from the Moon and it would be clearer than the
18:47
Speaker 1: one you take on Earth because there wouldn't be any
18:49
Speaker 1: atmosphere fuzzing it up. Right, you can take a picture
18:52
Speaker 1: where the sun don't shine and you might see a
18:54
Speaker 1: lot of interesting things, and it might even be p
18:57
Speaker 1: g rated. And you can actually see these because the
19:00
Speaker 1: International Space Station right orbits the Earth, and so sometimes
19:03
Speaker 1: it's in the shadow of the Earth. And so if
19:05
Speaker 1: you google these, you can see photos from the International
19:08
Speaker 1: Space Station that do show stars. They really are there,
19:11
Speaker 1: right right. I guess you don't need to be in
19:14
Speaker 1: a shadowy or dark place. Can you just point your
19:16
Speaker 1: camera away from the Sun or not in the direction
19:18
Speaker 1: of the Sun or anything like the Moon or Earth
19:20
Speaker 1: bouncing light? Yeah, there's definitely an advantage to being in
19:23
Speaker 1: space because you don't have the atmosphere bouncing off the
19:26
Speaker 1: light everywhere like here on Earth. You can't do that
19:28
Speaker 1: because the Sun's light is hitting the atmosphere and then
19:31
Speaker 1: coming down to your camera basically from every angle out
19:34
Speaker 1: in space. You're right, it's only direct sunlight. But the
19:36
Speaker 1: moon itself is bright, right, the moon is reflecting. The
19:39
Speaker 1: reason we see the moon down here on Earth is
19:41
Speaker 1: that the Sun's light bounces off the Moon and then
19:43
Speaker 1: comes back down to the Earth, so you don't have
19:45
Speaker 1: the atmosphere messing up your photograph. But still there's ambient
19:49
Speaker 1: light from lots of other places, like the moon itself
19:51
Speaker 1: is basically reflecting the Sun. I guess the main answer
19:54
Speaker 1: is just that you know, light from far away stars
19:57
Speaker 1: is very rare. The photos are rare. They might not
20:00
Speaker 1: becoming directly at your camera or your eyeball. If you
20:03
Speaker 1: want to see them, you need to leave your eyes
20:05
Speaker 1: open for a very long time or your camera shutter
20:08
Speaker 1: open for a very long time, which usually doesn't quite
20:10
Speaker 1: work exactly. To see those stars, you need to avoid
20:13
Speaker 1: any other bright source of light so that you can
20:16
Speaker 1: effectively make out very dim sources. Great. So, hopefully that
20:19
Speaker 1: answers Simon's questions and um may puts away another conspiracy
20:24
Speaker 1: theory about the Apollo program. All right, let's get into
20:26
Speaker 1: these other questions about antimatter stars and eating Jupiter. But first,
20:30
Speaker 1: let's take a quick break. All right, we're answering listener questions,
20:46
Speaker 1: and we just answered one about space pictures, and now
20:50
Speaker 1: we also have a new question here from Petrie, who
20:53
Speaker 1: has a question about anti matter stars. Daniel Hory, my
20:58
Speaker 1: name is Petrie, and I have some questions about antimatter stars.
21:01
Speaker 1: I recently read an article which described possible observations of
21:04
Speaker 1: antimatter stars by an instrument aboard the International Space Station.
21:08
Speaker 1: I wonder how likely is it that antimatter stars exist?
21:12
Speaker 1: If they do exist, what would happen if two galaxies
21:14
Speaker 1: collided and one of those galaxies contained antimatter of stars?
21:18
Speaker 1: Would we be able to tell I know that during
21:21
Speaker 1: galactic collisions, the odds of two stars colliding is small,
21:24
Speaker 1: but what about the interstellar dust? Would non antimatter interstellar
21:29
Speaker 1: dust annihilate when interacting with an antimatter star? And could
21:32
Speaker 1: we detect this? Thanks for all the great podcasts and
21:35
Speaker 1: keep up with good work. That's definitely a supervillain network
21:41
Speaker 1: right there, plotting a way thinking about antimatter, like how
21:45
Speaker 1: can I create the biggest exclusion a whole galaxy of
21:48
Speaker 1: antimatter that does sound pretty dramatic. I'm gonna pop some
21:50
Speaker 1: popcorn when you make that happen if you used antimatter
21:53
Speaker 1: of colonels that they would pop X for fluffy gut here.
21:56
Speaker 1: But thank you Petrey for this question. And this is
21:59
Speaker 1: a pretty interesting question. I guess this question is are
22:01
Speaker 1: there antimatter stars? Like, we know that antimatter might exist,
22:06
Speaker 1: and we know that there are stars, and so can
22:08
Speaker 1: you put the two together and can you make a
22:10
Speaker 1: star out of antimatter? Yeah, it's a really fun question.
22:14
Speaker 1: And I love these combination questions, you know, like let's
22:17
Speaker 1: combine too crazy things and make a crazy thing squared?
22:20
Speaker 1: Can I make an antimatter black hole? Daniel, It's like
22:24
Speaker 1: an anti question. I'm not against it. So the cool
22:26
Speaker 1: thing about antimatter is that it's basically exactly the same
22:29
Speaker 1: as matter, except it has all of its quantum numbers flipped.
22:33
Speaker 1: By quantum numbers we mean like electric charge and the
22:36
Speaker 1: other kinds of charges like weak hypercharge and color charge,
22:41
Speaker 1: all the charges that have to do with forces. But
22:43
Speaker 1: as far as we know otherwise, it's the same, which
22:46
Speaker 1: means that you should be able to build things out
22:49
Speaker 1: of antimatter the same way you can build things out
22:51
Speaker 1: of matter, like you should be able to take an
22:53
Speaker 1: anti proton and combine it with an anti electron to
22:57
Speaker 1: make anti hydrogen. And we've done that, and we've seen
23:00
Speaker 1: that anti hydrogen behaves exactly the same way as hydrogen.
23:04
Speaker 1: It has the same energy levels as all the same physics,
23:08
Speaker 1: and so we suspect that antimatter works really the same
23:11
Speaker 1: way as matter, And there's no reason why you couldn't
23:13
Speaker 1: build elements and molecules and all sorts of complex stuff,
23:18
Speaker 1: even up to stars out of antimatter. You can make
23:21
Speaker 1: anti people perhaps or anti antifa's. So it's not theoretical,
23:26
Speaker 1: it's like an actual I mean, it's it started out
23:28
Speaker 1: as a theory, but you've been able to make it
23:31
Speaker 1: in particle colliders. But I think maybe you haven't been
23:34
Speaker 1: able to study it quite that thoroughly, right, because it's
23:37
Speaker 1: kind of hard to make and it's really hard to handle,
23:39
Speaker 1: so you can't sort of test it the way you
23:41
Speaker 1: can normal matter. Yeah, it's not easy to make anti matter.
23:44
Speaker 1: You've got to smash particles and other particles are really
23:47
Speaker 1: high energy to make heavy, unstable particles which then sometimes
23:50
Speaker 1: decay into antimatter. So we sometimes can make it, and
23:54
Speaker 1: we have produced it at CERN, but it's like pico
23:57
Speaker 1: grams of antimatter. It's very, very difficult to make large quantities,
24:01
Speaker 1: and as you say, it's difficult to deal with because
24:04
Speaker 1: it comes into contact with normal matter and boom, it annihilates.
24:07
Speaker 1: Like if an electron meets and anti electron, they like
24:11
Speaker 1: to interact, and they interact and turn into a photon.
24:13
Speaker 1: So that's turning all the mass of those particles directly
24:16
Speaker 1: into energy. By e equals mc squared. And because C
24:20
Speaker 1: squared is a big number, when you're multiplied by mass,
24:23
Speaker 1: you've got a big energy. So combining matter and antimatter
24:26
Speaker 1: into energy releases a huge amount of energy. So yeah,
24:29
Speaker 1: it's difficult to handle and it's difficult to do big
24:32
Speaker 1: experiments on, Like we've never made enough antimatter to do
24:36
Speaker 1: even simple tests like does antimatter feel gravity the same
24:40
Speaker 1: way matter does? We don't know because we've never made
24:43
Speaker 1: enough of it. Right, Like you could maybe make a
24:45
Speaker 1: ball of antimatter and find that it floats or something right,
24:48
Speaker 1: or like have feels anti gravity and so we shoot
24:51
Speaker 1: off into space, I know, and that seems ridiculous, but
24:53
Speaker 1: we just don't know, and stranger things have been true
24:57
Speaker 1: in the universe, So it's possible that antimatter feels anti gravity.
25:02
Speaker 1: You know. It's just the kind of thing we've got
25:03
Speaker 1: to go out and check. But it's difficult to do
25:06
Speaker 1: because the universe seems to be made almost entirely of matter.
25:10
Speaker 1: As far as we know, everything in the Solar System
25:12
Speaker 1: is made out of matter, as far as we know,
25:13
Speaker 1: everything in our galaxy is made out of matter, though
25:16
Speaker 1: we're not right. So it's sort of like regular matter,
25:20
Speaker 1: and that it sort of looks the same like an
25:21
Speaker 1: anti electron looks like an electron. It just has a
25:24
Speaker 1: lot of these quantum numbers flipped, and so you don't
25:28
Speaker 1: know everything about it, but you do know that it
25:30
Speaker 1: it could probably and it has formed atoms with antimatter, yeah,
25:34
Speaker 1: and we have constructed those atoms, like they've done these
25:36
Speaker 1: experiments at certain where they put an anti proton together
25:39
Speaker 1: with an anti electron and they made anti hydrogen and
25:42
Speaker 1: it survived for a while and they studied it. So
25:44
Speaker 1: that's not theoretical, that is real. And we see antimatter
25:47
Speaker 1: all the time also in cosmic rays, like it's produced
25:51
Speaker 1: when stuff hits the atmosphere. Creates these big showers. These
25:55
Speaker 1: one really high energy particle bumps into a bit of
25:58
Speaker 1: the atmosphere and creates two part goals with half the energy,
26:01
Speaker 1: which then creates four particles with the quarter of the energy, etcetera.
26:03
Speaker 1: And you get this big shower of particles, and a
26:05
Speaker 1: lot of those have antimatter particles in them that don't
26:08
Speaker 1: last very long. They pretty quickly annihilate with stuff in
26:11
Speaker 1: the atmosphere. So most of the universe is made out
26:13
Speaker 1: of matter, but antimatter is something that we can create,
26:16
Speaker 1: and we can also find it occasionally in nature. Right,
26:18
Speaker 1: And so if it feels gravity the same way that
26:21
Speaker 1: matter feels gravity, then it is technically possible to make
26:24
Speaker 1: like hydrogen antimatter, and then a bunch of those up
26:27
Speaker 1: to make an antimatter star, right, Like it would be
26:30
Speaker 1: fusing at the core just like a regular star wood,
26:33
Speaker 1: but it would all be antimatter. Yeah, And there's a
26:36
Speaker 1: little bit of subtlety there, like, if it feels gravity
26:39
Speaker 1: the same way that our matter feels gravity, then yes,
26:43
Speaker 1: it would accumulate. If it feels anti gravity, then it
26:46
Speaker 1: would depend on exactly the kind of anti gravity, like
26:49
Speaker 1: it might be that it feels attractive gravity with other antimatter,
26:53
Speaker 1: but repulsive gravity with matter, in which case it could
26:57
Speaker 1: still again accumulate into a star. But if it feels
27:00
Speaker 1: some sort of weird anti gravity where it repels any
27:03
Speaker 1: other kind of mass, then you wouldn't be able to
27:06
Speaker 1: gather it together. It would always like repel itself. But
27:09
Speaker 1: if it feels any kind of accumulative gravity where it
27:11
Speaker 1: pulls itself together, then in principle you could pull it
27:14
Speaker 1: together and you could accumulate a lot of it, and
27:16
Speaker 1: you could make a star. Because we think that the
27:18
Speaker 1: strong force and the weak force and all these things
27:21
Speaker 1: treat matter and antimatter very similarly, So the fundamental processes
27:25
Speaker 1: that go on inside a star should also work for
27:28
Speaker 1: antimatter fusion. For example, you should be able to fuse
27:31
Speaker 1: anti hydrogen together to get anti helium. Interesting, and would
27:35
Speaker 1: it give out the same kind of light as our
27:37
Speaker 1: sun or would it give some sort of like anti
27:39
Speaker 1: version of light. Yeah. The cool thing about light is
27:41
Speaker 1: that it is its own anti version, Like the anti
27:45
Speaker 1: photon is just the photon. The photon is its own
27:48
Speaker 1: anti particle. And that has to be the case because
27:50
Speaker 1: what happens when antimatter meets matter, it gives off a photon,
27:54
Speaker 1: right that one particle. The photon unifies matter and antimatter.
27:58
Speaker 1: It's like the gateway between them, so it has to
28:01
Speaker 1: be the same particle. And so we think that if
28:03
Speaker 1: there are antimatter stars out there, they should shine in
28:06
Speaker 1: real light the same way normal stars do. So just
28:09
Speaker 1: by looking at a star, it would be hard to
28:12
Speaker 1: know if it's an antimatter star. But stars don't just
28:16
Speaker 1: create light, they also create particles, like our star creates
28:19
Speaker 1: the solar wind, and the solar wind is mostly matters, protons,
28:23
Speaker 1: and electrons, So an antimatter star would have an antimatter
28:26
Speaker 1: solar wind, which consists mostly of antiparticles and like many
28:30
Speaker 1: more anti new trinos than new trinos. So there are
28:34
Speaker 1: ways to tell if a star is a matter star
28:36
Speaker 1: or an antimatter star. Oh, you could get wind of
28:39
Speaker 1: its matterness or on its pocisition on matter. You know
28:43
Speaker 1: what happens if anti wind blows into uranus. I wanted
28:48
Speaker 1: on the record that it was a physicist who made
28:50
Speaker 1: that joke, not the cartoonists. Even I wouldn't go to that.
28:55
Speaker 1: You walked me to the ledge, man, You walked me
28:56
Speaker 1: to the ledge and then I nudged you. I see,
28:59
Speaker 1: I blew some antimatter windland you and it puts you over. Well.
29:03
Speaker 1: I guess I'm a little disappointed because I would have
29:04
Speaker 1: thought maybe like an antimatter star would I don't know,
29:07
Speaker 1: to the opposite of light, like it would suck in
29:08
Speaker 1: life or something. That's a black hole. Man, that's our
29:15
Speaker 1: black holes antimatter stars, Daniel, let's misinformed the public know.
29:19
Speaker 1: The cool thing about antimatter is that it could have
29:21
Speaker 1: been matter. Right, as far as we can tell, there
29:23
Speaker 1: really aren't many differences between matter and antimatter, and so
29:26
Speaker 1: one of the deepest questions in physics is why is
29:29
Speaker 1: our universe made out of this kind of matter and
29:31
Speaker 1: not the other one? Obviously, if it had been made
29:34
Speaker 1: out of antimatter, we would have called it matter and
29:36
Speaker 1: the other one antimatters. There really the question is like,
29:38
Speaker 1: why are there two kinds and why did one get
29:42
Speaker 1: left over? Because we think that in the very beginning
29:44
Speaker 1: in the Big Bang, there were equal amounts of matter
29:47
Speaker 1: and antimatter made, but now there's only matter left because
29:50
Speaker 1: a lot of the matter and antimatter annihilated itself and
29:52
Speaker 1: disappeared in two photons. But why is matter preferentially left over?
29:57
Speaker 1: Was there a little bit more antimatter made in the
30:00
Speaker 1: the universe? Or is there something out there that prefers
30:03
Speaker 1: to go to matter instead of antimatter. It's not a
30:06
Speaker 1: question we know the answer to, and it really like
30:08
Speaker 1: sets the stage for everything. It's it's like, why are
30:11
Speaker 1: we even here? Right? And I think that was part
30:13
Speaker 1: of Petrie's question, which is like, if there was an
30:15
Speaker 1: antimatter star out there, would we be able to tell
30:18
Speaker 1: the difference? Or like if there was a whole galaxy
30:20
Speaker 1: made out of antimatter, would we be able to tell
30:22
Speaker 1: that it is an antimatter galaxy? And so I guess
30:24
Speaker 1: maybe a follow up question is like how do you
30:26
Speaker 1: know there isn't more antimatter in the universe? Like, how
30:29
Speaker 1: do we know the galaxies we see in the night
30:30
Speaker 1: s guy aren't made out of antimatter? Yeah, it's a
30:33
Speaker 1: great question, we're not. We have two ways to look
30:36
Speaker 1: for it. One is that we expect if there are
30:39
Speaker 1: antimatter stars out there, or antimatter galaxies or antimatter regions
30:43
Speaker 1: of the universe, that they will be putting out antimatter radiation.
30:48
Speaker 1: And when that antimatter radiation hits the radiation from the
30:51
Speaker 1: matter parts of the universe, it will annihilate. So like
30:54
Speaker 1: halfway between a star and an antimatter star, or between
30:58
Speaker 1: a galaxy and an to matter galaxy, you should see
31:01
Speaker 1: like a whole wall where particles are hitting each other
31:03
Speaker 1: annihilating and turning into photons. So these like flashes of
31:07
Speaker 1: light in the middle of space. And so we've looked
31:10
Speaker 1: for these kinds of flashes, and we even know like
31:12
Speaker 1: what energy they should be at, but we don't see them.
31:16
Speaker 1: We don't see those anywhere, and that rules out there
31:19
Speaker 1: being like significant antimatter stars in our galaxy or in
31:22
Speaker 1: our galaxy cluster, and probably even further than that. That
31:26
Speaker 1: it gets difficult because now you're looking for like low
31:28
Speaker 1: energy photons from pretty far away. So we can't, for example,
31:32
Speaker 1: rule out there being a huge antimatter region of the
31:35
Speaker 1: universe out beyond the observable universe because we just can't
31:38
Speaker 1: see it. But we can pretty much rule out there
31:40
Speaker 1: being big antimatter regions of the universe because of these
31:43
Speaker 1: photon flashes that we would see if they were there.
31:46
Speaker 1: I guess maybe if the universe does have a matter
31:49
Speaker 1: preference over antimatter. Maybe it couldn't those antimatter particles turn
31:53
Speaker 1: into matter by the time they get to other galaxies. Well,
31:55
Speaker 1: there is a conservation of electric charge, and so for example,
31:59
Speaker 1: a positron anti electron can't just turn into an electron, right,
32:03
Speaker 1: you have to conserve electric charge. And so these things
32:06
Speaker 1: are pretty persistent. And that's the other way we look
32:09
Speaker 1: for antimatter stars or antimatter galaxies is that we look
32:13
Speaker 1: for those antimatter particles coming from them. So Petri mentioned
32:16
Speaker 1: this really cool experiment on the space station. It's called
32:19
Speaker 1: a MS and it's on the space station. It's basically
32:22
Speaker 1: a big magnet with a particle detector and it takes
32:25
Speaker 1: particles that shoot through it and it bends them so
32:27
Speaker 1: we can tell are you positively charged or negatively charged?
32:30
Speaker 1: And it measures their mass and stuff. And the really
32:33
Speaker 1: cool thing is that they think they have seen to
32:36
Speaker 1: anti helium particles coming through in the last few years.
32:41
Speaker 1: What do you mean they you can actually detect that
32:43
Speaker 1: it's anti helium. Yeah, you can detect that it's anti
32:46
Speaker 1: helium because you measure it's charge and you measure its mass.
32:49
Speaker 1: You can do all sorts of studies on it. Now
32:51
Speaker 1: it's not exactly conclusive. It's not like they trapped and
32:53
Speaker 1: took pictures and probed it, so it just passes through
32:56
Speaker 1: their detector. So there's a chance that what they've seen
32:59
Speaker 1: is actually something else. But it looks a lot like
33:01
Speaker 1: anti helium, and that's pretty amazing because anti helium is
33:05
Speaker 1: not just something you expect to be around, like we
33:08
Speaker 1: see anti protons occasionally in cosmic rays, we see anti electrons,
33:13
Speaker 1: but anti helium that's the kind of thing that would
33:15
Speaker 1: be made in the heart of an antimatter star. And
33:18
Speaker 1: so seeing one you could shrug that off. Seeing two
33:22
Speaker 1: that's pretty weird and interesting. So we don't know if
33:25
Speaker 1: this means that this is like a messenger from an
33:27
Speaker 1: anti matter star somewhere in the milky Way. Whoa, it's
33:32
Speaker 1: just from an anti balloon that it escape. But I
33:35
Speaker 1: guess how do you catch an anti helium? Wouldn't it
33:37
Speaker 1: annihilate with the stuff that you're trying to detect it
33:40
Speaker 1: with when it didn't create any an explosion? Yeah, but
33:42
Speaker 1: that's what we do with particles, was that we explode them,
33:45
Speaker 1: right the way we detect particles as we destroy them,
33:47
Speaker 1: you know, we have them interact with stuff and deposit
33:50
Speaker 1: their energy. And so the way MS works has a
33:52
Speaker 1: big magnet and it sucks stuff in and it bends
33:55
Speaker 1: it and then it gets it to interact with the
33:57
Speaker 1: matter of that detector. And it doesn't like blow up
34:00
Speaker 1: the detector because we're talking about tiny little particles, so
34:02
Speaker 1: it's not like a bomb or anything. You know. We
34:04
Speaker 1: create anti matter all the time. It's a large hadron
34:07
Speaker 1: collider and it flies through our detector and interacts you know,
34:10
Speaker 1: positrons and anti muans and stuff. We detect them the
34:13
Speaker 1: same way did we detect other stuff, just by getting
34:15
Speaker 1: them to interact with our matter. Cool. Well, I guess
34:18
Speaker 1: my question now is if you if you breathe in
34:20
Speaker 1: anti helium from a balloon, will it make your voice
34:22
Speaker 1: deeper or higher pitch like regular helium. Nobody knows the
34:27
Speaker 1: answer to that question. Hey, And that's the first experiment
34:30
Speaker 1: will do when we make enough anti helium. All right,
34:33
Speaker 1: all right, I'll put my name on the waiting list there.
34:36
Speaker 1: But there was one more little part to his question,
34:37
Speaker 1: which was what would happen if we collided a galaxy
34:41
Speaker 1: with an anti galaxy. I'm guessing um a lot would happen. Yes,
34:45
Speaker 1: a lot would happen, big explosion. Yeah, because, as he says,
34:48
Speaker 1: stars are pretty diffused and so they wouldn't necessarily collide
34:51
Speaker 1: with each other, but they're also pumping out a lot
34:53
Speaker 1: of stuff, and the dust and the gas would also
34:55
Speaker 1: be antimatter, so there would be a lot of collisions,
34:58
Speaker 1: just sort of like with the Bullet cluster. When we
35:00
Speaker 1: saw those two collisions. The stars mostly passed through each other,
35:03
Speaker 1: but the rest of the stuff, that gas in the
35:05
Speaker 1: dust definitely collided. So it would be pretty dramatic, right,
35:08
Speaker 1: I guess galaxies are pretty sparse, and so it's like
35:11
Speaker 1: throwing a bunch of sand at another bunch of sand,
35:14
Speaker 1: and most of them would just go through itself. Yeah,
35:17
Speaker 1: most of the stars would, but the gas in the
35:19
Speaker 1: dust would definitely interact. And you're saying, we haven't seen
35:21
Speaker 1: that kind of you know, event, So maybe that's kind
35:24
Speaker 1: of evidence that there aren't antimatter galaxies or antimatter stars. Yeah,
35:28
Speaker 1: but we can't really explain this result from a MS
35:31
Speaker 1: like two anti helium particles. There is a lot more
35:34
Speaker 1: than you expect to see if there are no antimatter stars.
35:37
Speaker 1: On the other hand, it's preliminary, so it could just
35:40
Speaker 1: be a fluke, could be a mistake. We're not exactly sure,
35:43
Speaker 1: but it's a tantalizing clue. All right. Well, then, to
35:46
Speaker 1: answer Petrie's question, are there antimatter stars? Um, we don't
35:50
Speaker 1: quite know, right. I mean, it's theoretically possible from what
35:53
Speaker 1: we know about antimatter, but we don't see a lot
35:56
Speaker 1: of evidence for antimatter stuff out there in the universe,
35:58
Speaker 1: except for maybe these two anti helium particles that the
36:01
Speaker 1: space station just found. All right, well, let's get into
36:04
Speaker 1: our last question of the day, and this one it's
36:07
Speaker 1: about aliens eating Jupiter, which hopefully hasn't happened. I don't think,
36:12
Speaker 1: but let's get into it. But first let's take a
36:14
Speaker 1: quick break. All right. Listen to question number three for
36:29
Speaker 1: the day, comes from Joe, who has a question about
36:33
Speaker 1: hungry aliens. Hi. I wanted to ask a science fiction question.
36:39
Speaker 1: I was wondered if aliens were, for some reason just
36:42
Speaker 1: to make a pit stop on our solar system and
36:45
Speaker 1: steal off all our gas giants too U to use
36:49
Speaker 1: this fuel, would that affect our orbit at all? Would
36:53
Speaker 1: Earth's climate be affected by that? I have a follow
36:56
Speaker 1: up question as well, Um, if they were to remove
37:00
Speaker 1: those gas planets. Would that also have any kind of
37:04
Speaker 1: effect on our ability to leave the Solar system? Would
37:07
Speaker 1: that take our ability to fuel some kind of warp
37:10
Speaker 1: drives or whatever away from us? All right, interesting question
37:13
Speaker 1: from Joe and his baby. I'm guessing it's the one
37:17
Speaker 1: feeding him the questions and was really impatient to hear
37:20
Speaker 1: the answer. I don't know, but apparently asking us these
37:23
Speaker 1: questions is more important than whatever his baby needed. Well,
37:27
Speaker 1: maybe the question is somehow related to the baby. Maybe
37:30
Speaker 1: the baby is the alien and the baby is really hungry,
37:33
Speaker 1: so he's like, what if I feeded Jupiter would stop
37:36
Speaker 1: crying for the rest of his life? Uhh, And when
37:38
Speaker 1: the mom gets back, what did you feed our baby
37:42
Speaker 1: a lot of gas? Or maybe he's just thinking about
37:46
Speaker 1: the future that this baby will inherit and wondering how
37:49
Speaker 1: we will deal with the inevitable galactic empire that's going
37:52
Speaker 1: to come and visit us and pose us these difficult questions. Yeah,
37:55
Speaker 1: I noticed he had a follow up question, which I think,
37:57
Speaker 1: you know, tells me that he's he's thought of this through,
38:00
Speaker 1: like he's thought about it and he thought about the
38:02
Speaker 1: implications of it. All right, So well, the question is
38:04
Speaker 1: what if aliens aide Jupiter, And I think he means
38:07
Speaker 1: more like, what if Jupiter suddenly disappeared, Like what would
38:10
Speaker 1: be the consequences with it throw our Solar system into chaos?
38:14
Speaker 1: And his follow up question was, will it sort of
38:17
Speaker 1: take away a huge source of possible fuel for us
38:20
Speaker 1: to go see the stars? Yeah, it's really cool to
38:23
Speaker 1: think about Jupiter versus the Earth, and it gives you
38:26
Speaker 1: a sense of like the scale of these objects because remember,
38:29
Speaker 1: Jupiter is like much much bigger than the Earth. They
38:32
Speaker 1: like dwarfs the Earth. On the other hand, Jupiter itself
38:36
Speaker 1: is dwarfed by the Sun. Right. The Sun is like
38:39
Speaker 1: points something per cent of all the mass in the
38:42
Speaker 1: Solar System. Jupiter is like the rest of it. But
38:46
Speaker 1: the Sun is like a thousand times more massive than Jupiter.
38:51
Speaker 1: So when you're doing like gravitational calculations to ask like
38:54
Speaker 1: what's tugging on the Earth. What's important for the Earth,
38:57
Speaker 1: it's mostly the Sun. Everything else you can ignore because
39:01
Speaker 1: not just is the Sun more massive than Jupiter, it's
39:04
Speaker 1: also closer to us than Jupiter. Like Jupiter, it's pretty
39:08
Speaker 1: far out there, and so the gravitational force on the
39:12
Speaker 1: Earth from the Sun is twenty five thousand times more
39:16
Speaker 1: powerful than the gravitational force on the Earth from Jupiter.
39:20
Speaker 1: You're saying, Jupiter is big, but it's far away, and
39:23
Speaker 1: it pales in comparison to the Sun. Now at one
39:27
Speaker 1: and twenty five thousand seems like very little, But I
39:30
Speaker 1: don't know. Maybe in space, these small differences make a
39:32
Speaker 1: huge difference. It does definitely affect the trajectory of the Earth.
39:35
Speaker 1: So if you've got rid of Jupiter, it would have
39:38
Speaker 1: a small effect on Earth trajectory. You know, it would
39:41
Speaker 1: change like the elliptical nature a little bit, but we
39:43
Speaker 1: would still have a stable orbit and it wouldn't affect
39:46
Speaker 1: us in a way that we could measure, like, it
39:48
Speaker 1: wouldn't affect the radiation we're getting from the Sun, etcetera.
39:51
Speaker 1: All right, so it would maybe change or weather a
39:54
Speaker 1: little bit, but it wouldn't like throws off of the
39:56
Speaker 1: Solar system. Yeah exactly. We would still be stable. And
40:00
Speaker 1: you know, people have done these calculations and it depends
40:02
Speaker 1: a little bit on where Earth lands. But if you
40:05
Speaker 1: just like delete Jupiter, you definitely get a stable orbit
40:08
Speaker 1: and most of the times it's almost essentially unchanged from
40:11
Speaker 1: its current orbit. Whoa people have done these calculations, like
40:14
Speaker 1: people are planning for this, somehow we're expecting this. I
40:18
Speaker 1: actually assigned this as a problem in one of my
40:21
Speaker 1: programming classes to do like numerical simulations of the Solar
40:24
Speaker 1: System and consider what would happen if a new planet
40:26
Speaker 1: came in or if you deleted a planet. It's pretty
40:29
Speaker 1: fun to see, like the chaotic events that transpire when
40:32
Speaker 1: you mess with the Solar System. So interesting. I see
40:35
Speaker 1: you've been outsourcing your villainy to your students. I've been
40:38
Speaker 1: inviting young scientists to participate in these intellectual explorations in
40:44
Speaker 1: your intellectual villany. Yes, that's what I'm saying now, I'm
40:48
Speaker 1: just kidding. So it would have a small effect on Earth,
40:50
Speaker 1: but maybe would it have a ripple effect on the
40:52
Speaker 1: rest of the Solar System. Like you know, one thousand
40:55
Speaker 1: seems small, but if you added up to all the
40:58
Speaker 1: other things happening in the Solar System could throw it
41:01
Speaker 1: into chaos. It definitely would affect the rest of the
41:03
Speaker 1: Solar System because there's stuff out there that's much closer
41:06
Speaker 1: to Jupiter, and that is where Jupiter is basically the
41:09
Speaker 1: dominant gravitational effect, like the asteroid belt is huge collection
41:13
Speaker 1: of rocks. Some of them are between Mars and Jupiter,
41:17
Speaker 1: and they're very very strongly affected by jupiter gravity, and
41:20
Speaker 1: some of them are actually in orbit with Jupiter. They're
41:23
Speaker 1: like part of Jupiter's orbit. They're like co orbiting. So
41:26
Speaker 1: Jupiter is the big boy out there and it is
41:28
Speaker 1: definitely in charge of what's going on. And if you
41:30
Speaker 1: deleted Jubiter, then it would totally disrupt the asteroid belt.
41:33
Speaker 1: They would would become chaotic very quickly, and they would
41:36
Speaker 1: get all new trajectories, right, and maybe that could disrupt
41:39
Speaker 1: things and maybe throw on asteroid our way, right, it
41:41
Speaker 1: could maybe spelled doom for us that way. Yeah, because
41:44
Speaker 1: what Joe didn't specify also is what would happen to
41:47
Speaker 1: the moons of Jupiter. Like if they just delete Jupiter
41:50
Speaker 1: and leave its moons, then those moons are suddenly flying
41:53
Speaker 1: through space without the gravitational force needed for their orbits.
41:57
Speaker 1: So depending on their angles, like they could plummet into
42:00
Speaker 1: the Sun, they could shoot out of the Solar System,
42:02
Speaker 1: or they could like start orbiting the Sun on their own.
42:05
Speaker 1: And you know, some of those things are pretty big,
42:08
Speaker 1: Like they're bigger than mercury and so we'd have like
42:10
Speaker 1: a new planet. You know, Io could be a new
42:12
Speaker 1: planet if you deleted Jupiter. Whoa, that would be the
42:17
Speaker 1: ultimate poking the eye for Pluto. If like a moon
42:20
Speaker 1: got upgraded, well it got downgraded, yeah, I know, talk
42:23
Speaker 1: about promotion or you know, one of them could plow
42:26
Speaker 1: through into the inner Solar System, disrupting the asteroid belt,
42:29
Speaker 1: and that would not be great for the Earth because
42:31
Speaker 1: a lot of those things could end up hitting the Earth.
42:34
Speaker 1: You know, most of those are in stable orbits and
42:36
Speaker 1: NASA is monitoring them and we don't think any of
42:38
Speaker 1: them are on trajectory to hit the Earth anytime soon,
42:41
Speaker 1: but a big charac event like that could definitely shake
42:43
Speaker 1: that up. Alright, well, I guess the answer to the
42:46
Speaker 1: first part of the question is that it wouldn't affect
42:48
Speaker 1: us that much gravitationally, but it might who knows, trigger
42:52
Speaker 1: some kind of a random fluke event that could kill
42:54
Speaker 1: us potentially. So if the aliens come and you offer
42:59
Speaker 1: them to better, remember that still has consequences for the
43:02
Speaker 1: Earth because we're all one solar system. Man. Yeah, maybe
43:06
Speaker 1: point them to the nearest solar system and get them
43:09
Speaker 1: to eat those over there. We hear that Alpha Centauri
43:12
Speaker 1: is really really nice and chewy this time of year. Yeah,
43:15
Speaker 1: they have a better buffet. Ye have better desserts. What
43:19
Speaker 1: about the second part of his question though, like would
43:21
Speaker 1: it rob us of potential fuel for space exploration, Like
43:26
Speaker 1: we know Jupiter is full of you know, gas that
43:29
Speaker 1: we could maybe use for some sort of fusion power
43:32
Speaker 1: space engine. Right, it's true, and if the Aliens are
43:34
Speaker 1: coming because they want to fuel up, then it's definitely
43:37
Speaker 1: a resource and it would suck to lose it. But
43:40
Speaker 1: you know, space is filled with these resources, Like there
43:43
Speaker 1: is water and hydrogen and all sorts of elements all
43:47
Speaker 1: over the Solar System. A lot of the things that
43:49
Speaker 1: seem rare and difficult to find on Earth are difficult
43:52
Speaker 1: to find only because you're on the surface of the Earth.
43:54
Speaker 1: You know, there's like asteroids that are huge chunks of platinum.
43:58
Speaker 1: So whatever you really need out there in the the system,
44:00
Speaker 1: you can pretty much find it even if you lost Jupiter.
44:03
Speaker 1: So I'm not too worried about that, But there are
44:06
Speaker 1: some consequences of losing Jupiter, Like we use Jupiter and
44:09
Speaker 1: Saturn the big planets right now, is like gravitational slingshots.
44:13
Speaker 1: You want to get out to Pluto, for example, one
44:16
Speaker 1: good way to do it is to aim at Jupiter
44:18
Speaker 1: and swoosh around it and have Jupiter like sling you
44:21
Speaker 1: out into the outer Solar system. And so we do
44:23
Speaker 1: these maneuvers. I think we had a whole podcast episode
44:25
Speaker 1: about how they work, and that's pretty helpful. So you'd
44:28
Speaker 1: be bummer to lose Jupiter for that reason. Also, Yeah,
44:31
Speaker 1: like you aim at Jupiter and then let Jupiter pull
44:34
Speaker 1: you out to where it is, and then once it
44:36
Speaker 1: pulls you in, you swing around and use that momentum
44:39
Speaker 1: to shoot off into the stars. Yeah, exactly. So it's
44:42
Speaker 1: a way without burning any fuel to gain some speed
44:45
Speaker 1: because you're stealing a little bit from Jupiter, and also
44:48
Speaker 1: to change direction. Ie, we wouldn't lose any important fuel
44:51
Speaker 1: because this solar system has other resources, but we would
44:55
Speaker 1: lose kind of like a nice step in stone to
44:57
Speaker 1: get out of this solar system. Yeah, could you use
44:59
Speaker 1: our a new moon io, I mean the new planet
45:02
Speaker 1: io instead. I suppose you could, but it doesn't have
45:07
Speaker 1: nearly the power gravitationally that Jupiter has. All right, Well,
45:10
Speaker 1: that answers the question for Joe, what if alian's a
45:13
Speaker 1: Jupiter not much, at least for now. So either way,
45:16
Speaker 1: aliens is what you're saying, Daniel, That's what I'm saying.
45:19
Speaker 1: Give us physics and then you're dig in. All right. Well,
45:23
Speaker 1: that answers are three amazing questions from our awesome listeners.
45:27
Speaker 1: Thanks again to Simon, Petrie and Joe for submitting their
45:30
Speaker 1: questions and recording them. If you have questions, at least
45:33
Speaker 1: email Daniel. That's right, and thank you everybody for using
45:36
Speaker 1: your curiosity to power this podcast and all of science.
45:40
Speaker 1: The reason that we're doing this stuff, the reason we
45:42
Speaker 1: are looking for answers to questions about the universe, is
45:45
Speaker 1: because we want to know, and we know that you
45:47
Speaker 1: want to know, Yeah, and we are happy to give
45:50
Speaker 1: you answers and also anti answers, which sort of behave
45:53
Speaker 1: the same way as answers to right until they collide
45:55
Speaker 1: with answers, right, and then they annihilate into pure mental energy.
45:59
Speaker 1: All right, Well, thanks for listening. We hope you enjoyed that.
46:03
Speaker 1: See you next time. Thanks for listening, and remember that
46:13
Speaker 1: Daniel and Jorge explained the Universe is a production of
46:16
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46:20
Speaker 1: Visit the I Heart Radio app Apple podcasts, or wherever
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