Interstellar Inquiries: The Quest for Planet Nine & Understanding Black Holes

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Heidi Campo: Welcome back to another fun, exciting

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Q and A episode of space

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nuts.

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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

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report it feels good.

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Heidi Campo: I am your substitute host for this episode,

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Heidi Campo. And joining us is professor

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Fred Watson, astronomer at large.

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How are you doing today, Fred?

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Professor Fred Watson: Um, I'm very well, thanks, Heidi, and great to see you, as

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always. And I hope you're well and I hope you're surviving the

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thunderstorm that apparently is going on around you at the moment.

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Heidi Campo: It is. You know, like I just said,

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would I would rather have a thunderstorm than a

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hurricane? Because I am here in Space Center Houston, not m.

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Space Center, Space City. I'm not in the

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Space Center. I'm in Space City. Um, we did have a

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hurricane last year that was not fun. Um,

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I was alone. My husband was traveling at the time for work, and

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I had a broken foot. My neighbor's tree.

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The trunk didn't fall, but almost all of the big

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branches did. So I was out there with a

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broken foot brace on my leg crutches and

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a chainsaw trying to chop up these

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branches and deal with it. Dealing with my

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first hurricane. And then we didn't have power

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for nine days. It was awful. In the middle

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of July. Oh, whoa, whoa.

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Professor Fred Watson: That's awful.

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Heidi Campo: So those are. I guess

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I just. Just sheer will, I

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guess. But those of you who live, um,

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in climates where you don't get hurricanes,

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enjoy those.

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M. Speaking of,

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looks like our first question today is from

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Jakob or Jacob. If I'm saying that right,

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I think it's Jakob from Norway.

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Uh, they do not get any hurricanes there. You are safe from

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hurricanes, and you get to enjoy the auroras.

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Jakob's, uh, question is,

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um. Hi, this is Jakob from Norway. I'm working on a

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presentation about planet nine for my school,

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where I will be comparing the mathematical

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prediction of the nine planet

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with Urbian. Lee

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Verriners. You'll have to correct me on that,

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Fred. Um, work to finding

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Neptune. In 1864, Lee

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Varenner saw that something was wrong with the

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orbit of Uranus and figured out that it was getting

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pulled on by another planet. He told astronomers

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exactly where to look for this planet. And surely

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enough, they found Neptune on the first night

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of looking. What are the odds of that? Now, almost

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200 years later, scientists see something wrong with some

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objects in the Jupiter belt and say that,

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excuse me, say that another planet may be causing these strange

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orbital paths. My question is,

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why can't we predict exactly where

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Planet Nine is like Lee Varenner did in

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1864. Have we gotten worse at

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maths? Thank you for the great podcast

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and.

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Professor Fred Watson: Thank you for the great question Jakob because

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um, you know you've hit the nail on the head there. You're

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quite right about uh, the discovery of

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Neptune. Um um it's

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usually said that Neptune was the first planet

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discovered with the point of a pen

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because it was calculations by Le Verrier

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and also um, actually a

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British ah, astronomer,

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uh, I think his name was Adams, I might be misremembering that

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uh, who did the calculations at the same time

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and also predicted the existence of another planet.

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But he couldn't get anybody in England interested in

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actually following up on it. Le Verrier

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um, basically was fortunate

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in having the director of the Berlin Observatory

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um, uh, to help him out. And

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that was when Neptune was discovered exactly where it was

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predicted. Now Planet nine, uh, you're

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absolutely right. There's a nice link

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there between um, 1846 and the

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early 2000s because it was back in

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2016 that two American astronomers

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figured out that there was something about

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the orbits of uh, objects

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as you mentioned in the Kuiper Belt, uh,

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which are uh, aligned in a way that

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suggested that there's another planet out there,

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uh, that's pulling them all into uh,

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this alignment, this orbital alignment,

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um, but we haven't found it yet and

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some suggest that, that it doesn't exist at all.

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And the difference between the discovery

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of Neptune and the search for Planet nine

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is that Neptune, uh the prediction of

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Neptune's existence was based on very

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accurate observations of one object which was the planet

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Uranus uh in the outer solar system. And

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it was what we call perturbations in the orbit of

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Uranus, Uh but that means

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it's being pulled out of

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what you'd normally expect to see. And it's that pulling

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that was attributed Neptune. And you can then because

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you're only looking at well three objects, the Sun,

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Uranus and the other, whatever mystery

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body it is which turned out to be Uranus. You can do the

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calculation and predict pretty exactly where you're going

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to find the as ah, yet unknown object. And that's

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what happened. It's a great story uh, with lots of

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twists and turns. It's a bit different with

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Planet nine. What we're seeing is uh, the

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suggestion uh, that some of the orbits of these

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Kuiper Belt objects are aligned in a way that

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uh, means that they're being pulled uh, out of

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a uh, different orbit by a hidden planet.

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But you're now talking about not accurate

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positions of gravitational pulls. You're talking about

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statistical, uh, uh, discussions

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because you're talking about many objects,

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uh, and you're talking about many orbits. And

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one of the reasons why, uh, this is such

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a difficult problem is that if there was an

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object pulling these, uh, Kuiper Belt

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objects into their elongated orbits, into their

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aligned orbits, uh, it would be a very long way

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away from the sun. It would be very faint and very

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difficult to see. But the other thing is

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you can't be sure that you're not

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seeing a statistical fluke. And a

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number of scientists have pointed this out that

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maybe the Kuiper Belt objects, these icy

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asteroids beyond the orbit of Neptune, uh,

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those objects are uh, just a small sound

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of what is a bigger sample that we have not yet

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discovered. And if we could see the whole sample, there

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wouldn't be an issue. There would be no preferred alignment.

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Uh, so it's what we would call a selection effect. It's a

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statistical fluke. So that's the bottom

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line with this. It's a statistical business

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rather than a, ah, direct gravitational

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um, calculation which is what it was for Neptune.

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So we haven't yet found planet nine. A lot of people are still looking.

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I'm kind of hopeful that we will do. But the latest

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results suggests that maybe it's not there at all.

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Heidi Campo: Sounds like, um, machine learning may be

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a very beneficial asset in

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discovering these statistics and

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advanced, advanced formulas to find this.

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Professor Fred Watson: That's right. I'm sure people are throwing

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AI at uh, this problem. Uh,

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there's only so much you can do though because you're limited

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with the data set that you've got to

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start with, which is something like, I don't know, I think they're about

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10 of these, uh, asteroids which are

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particularly aligned that suggest the existence of planet

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nine.

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Heidi Campo: This is true. This is true.

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Well, our next question is from

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Enrique and this is an audio question that we will

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play for you now.

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Henrique: Hello, I'm, um, Henrique from

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Portugal. Thank you for

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answering my last question about space

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time. I have another one.

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How do black holes have density

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if the singularity doesn't have

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volume? Thank you.

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Bye.

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Heidi Campo: It's always so sweet to hear from Enrique.

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Um, you said he was, uh, what did we say

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his last email said he was six.

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So. Is that right, Fred? I think when they emailed us before

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he said he was 6 years old.

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Professor Fred Watson: Yes, that's correct.

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Heidi Campo: Something like that, yeah. No Enrique, so cute.

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He's so smart too. I'm like, man, I was not thinking about

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this stuff when I was his age.

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Professor Fred Watson: Yeah, me neither. Sorry.

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Um, uh, just to let our listeners

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know that we are improvising here, we're listening

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separately to, uh, it might be

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Henrik rather than Enrique. Anyway, it's

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um, Henrik by the sound of it, from Portugal.

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And I was listening slightly after you, so

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I could. So that's why you, you didn't get a

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response from me to your question, which I'm sure Huw

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will tidy up when he edits this whole

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thing. Um, his question was, um,

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how can you have.

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How can an object have density when it's got zero

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volume? I, uh, think I'm paraphrasing that

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correctly. And, uh, Henrik has

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gone straight to the nub of the matter

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with a black hole because a black hole is

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effectively defined as a point in space which

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has infinite density. Uh,

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now black holes have mass and we can measure

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different masses for black holes. Some are supermassive black holes,

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uh, which have masses millions or even billions of

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times the mass of the sun. Uh, some are

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stellar, uh, mass black holes, which are similar in

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mass to the sun. Uh, but they all have mass.

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If they don't have volume, though, uh, you'll

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remember. Maybe you don't know this formula,

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Henrique. I, uh, don't think I did when I was 6.

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But density is mass divided by

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volum. If volume is zero, and that's the

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way we think a black hole is, then the density is

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infinite. Uh, because if you divide something

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by zero, the answer you get is infinity. Two very

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odd mathematical quirks. So,

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um, it's possible that

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real black holes don't have infinite density, but

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their densities are very, very high because a black

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hole by definition is either

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zero volume or at least a very, very small

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volume. Uh, so it's a great question and

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what you is, you've basically gone to the heart of what

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defines a black hole. Well done.

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Heidi Campo: And we absolutely need more young people interested

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in this stuff. I saw. Um, I'm

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actually. Oh, I'm gonna brag for a second. I am a brand new aunt for the

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first time. I had my first nephew. So

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shout out to baby Roman. So excited you're here.

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But I was looking through baby books and I guess they have the

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cutest little baby books these days. You can get quantum, um,

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physics for babies, astronomy, um, for babies,

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um, math for babies. They have all sorts of cute little book

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and I am so excited because I'm going to buy him all the science books in

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the world because their brains are little

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sponges and they can learn so much so fast. And

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I'm like, you know what we should do is we should have little kids

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solving these problems because they would probably come up with the

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answer faster than an adult

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would.0G.

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Professor Fred Watson: And I feel fine.

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Heidi Campo: Space Nuts. Well, our uh, next question.

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Professor Fred Watson: Congratulations on your um, on being an

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aunt.

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Heidi Campo: Thank you so much. Oh, I'm so excited. He's so cute.

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Um, our next question is from Ben.

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Um, Ben, looks like you're emailing us from

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Northwestern University. Ben says

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I don't know how common it is, but I do know

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for certain. I do know for certain things like

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gravitational wave detections, many

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observations will drop or uh, many

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observatories will drop what they're doing to

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attempt to observe the source of the waves.

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I have four questions about this.

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One, is it common for

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observatories to do this? Two,

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for what sort of events do

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observatories do this? Three,

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are there any sort of observations

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which are immune to these interruptions?

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And four, my understanding is that

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observing time is quite constricted, highly

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scheduled and difficult to obtain. So

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how do they compensate for these interruptions?

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Do they just move the entire schedule schedule back? Do they

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just find a different slot for the observations that were

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interrupted while keeping most

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observations unimpacted or something else?

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Professor Fred Watson: Thanks Heidi and Ben. That's um, a question that I

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don't think we've ever been asked before on Space Nuts.

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And it's a really good question because it's part and

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parcel of the work of

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your average observatory. Uh,

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and so the first of your four questions, is it common

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for observatories to do this? And the answer is

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yes. Uh, these are

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effectively what we call target of opportunity

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observations where uh, you know

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the scheduled use of a telescope. And you're

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absolutely right, those schedules are ah,

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laid down months in advance. People

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have applied for telescope time,

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sweat, blood and tears to actually uh,

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get their applications in and succeed in winning the

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telescope time. I used to do this quite a lot back in the day.

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Um, typically uh, on the Anglo Australian telescope, which

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is the one I used most, uh, the biggest visible uh,

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light telescope in Australia. Uh,

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typically for every night uh, of available

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observing time there will be three to four different

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groups wanting to use it. So that's the level of

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competition that there is. And of course only one

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wins out. And the result of that is you might be allocated

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two or three nights and four

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occasionally got fauna allocations where

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you're at the mercy of the weather, uh, and at the mercy

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of all the instruments working but you've worked so hard to get that

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time. Uh, the last thing you want is for

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somebody to come along and say, oh, there's been,

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uh, X, Y or Z happening in the space. We're going to grab

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your telescope. But, um, it is,

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uh, sort of built into most observatories

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that, that is a potential way of

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operating. I guess some don't. Uh,

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but certainly at the Anglo Australian Telescop,

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uh, these target of

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opportunity observations were made. Um,

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so, uh, Ben, your second question is for what sort of

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events do observatories do this? Well, as you

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said, uh, it's, you know, some of the gravitational wave

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detections in recent months of, um,

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neutron star collisions where there might be

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a radio or optical counterpart, in other

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words, a flash either in the radio spectrum or the

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visible light spectrum. Uh, then you would

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that the target of opportunity rules would kick

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in because there would have to be rules about this.

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Um, it works, I think, for radio telescopes as well. I

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don't have any direct experience of observing on

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radio, um, telescopes, but I do know about the other kind, the

324
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optical telescopes. And yes, your time

325
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will be taken over. So neutron star

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collisions, um, supernovae is the most common

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one. If you've got a bright supernova, uh,

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and you have a telescope that's got the right equipment on it,

329
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you will probably turn to that to detect,

330
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uh, the supernova explosion and measure its

331
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spectrum at the peak of its intensity. Uh,

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that's happened a lot. Gamma ray bursts,

333
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the visible light counterparts of things that are detected

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by gamma ray satellites. That's happened

335
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too. Uh, so these things are, um. You

336
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know, there are several transient, what we call transient

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phenomena for which this kind of, um,

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uh, observation would be made. Uh, number three, are there

339
00:16:01.990 --> 00:16:04.790
any sorts of observations that are immune to these interruptions?

340
00:16:04.790 --> 00:16:07.300
Well, that be. Would. Would depend, I think, on the

341
00:16:07.460 --> 00:16:10.420
policies of the particular observatory in question. There might

342
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well be, um, certainly at the aat,

343
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uh, there weren't. We did a lot of

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routine survey work where we were building up large

345
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catalogues of information on things. And that would

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00:16:21.579 --> 00:16:24.060
be very much, uh, something that could be

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interrupted by, uh, a target of

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opportunity observation. Uh, and four, my

349
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understanding is that observing time is quite constrained, highly

350
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scheduled and difficult to obtain. Indeed it is.

351
00:16:35.090 --> 00:16:38.040
So how do they compensate for those interruptions? Uh,

352
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do they just move the entire schedule back? No, they don't.

353
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Uh, what they do is the

354
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astronomers who've lost the time

355
00:16:46.690 --> 00:16:49.490
really, uh, have to face the fact that they've lost the time.

356
00:16:50.140 --> 00:16:52.810
Um, and that might be, you know, one of the

357
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conditions under which they accept the time, the telescope

358
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time in the first place. Um, often

359
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though, there will be, uh,

360
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you know, there will be moves to try and

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compensate, uh, for that loss

362
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of time. And that's the last part of your

363
00:17:10.280 --> 00:17:13.280
question. Do they just find a different slot for the

364
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observations that were interrupted while keeping most

365
00:17:15.960 --> 00:17:18.960
observations unimpacted? That's basically the way it

366
00:17:18.960 --> 00:17:21.920
works. Uh, and in the case of the

367
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Anglo Australian telescope, we had,

368
00:17:25.279 --> 00:17:27.840
uh, time. There was a small amount of time that was not

369
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allocated to users. We called it director's time

370
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because it was at the director's discretion

371
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to allocate that time, whether it was for hardware

372
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improvements or whatever tests, things of that sort.

373
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Uh, but, um, that is what normally would

374
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happen. The director would try and allocate some

375
00:17:45.540 --> 00:17:48.540
of his director's time to compensate for somebody who

376
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had lost time because of a target opportunity

377
00:17:50.980 --> 00:17:53.780
observation. The great question. Thanks very much,

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00:17:53.780 --> 00:17:54.180
Ben.

379
00:17:54.260 --> 00:17:57.060
Heidi Campo: Yeah, and I can attest to that. My good

380
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friend, um, Dr. Allison McGraw, she's a planetary

381
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scientist over at the Lunar and Planetary Institute,

382
00:18:03.060 --> 00:18:05.640
and she is always competing to get the best

383
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telescope time. Um, she was just in Hawaii not

384
00:18:08.520 --> 00:18:11.360
too long ago and she was so excited because it was perfect,

385
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perfect conditions and she got everything she wanted.

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Professor Fred Watson: Very good.

387
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Generic: Three, two, one.

388
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Heidi Campo: Space nuts.

389
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All right, so this brings us to our very last question for the

390
00:18:25.640 --> 00:18:28.440
evening, which is from Fenton. And this is

391
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an audio question that I will

392
00:18:31.390 --> 00:18:34.190
play for you now. I'll give Fred just a second

393
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to get synced up with me.

394
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Professor Fred Watson: Synced up with me.

395
00:18:36.670 --> 00:18:39.150
Heidi Campo: And then we can, we can both hit play

396
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at the same time and listen to Fenton's question, which

397
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you will hear now.

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Fenton: Hey, Fred and Andrew, this is Fenton from St. Paul,

399
00:18:46.310 --> 00:18:49.110
Minnesota, in the U.S. uh, I

400
00:18:49.110 --> 00:18:51.990
understand you guys need some questions, so here's one for you to think

401
00:18:51.990 --> 00:18:54.840
about. I really like, by the way, uh,

402
00:18:54.840 --> 00:18:57.770
everything that you do with the questions, whether they're good

403
00:18:57.770 --> 00:19:00.770
or bad, you always do a good job of coming

404
00:19:00.770 --> 00:19:03.330
up with something interesting on them. So

405
00:19:03.570 --> 00:19:06.290
you guys talk a lot about gravity

406
00:19:06.290 --> 00:19:08.890
waves. And I ask

407
00:19:08.890 --> 00:19:11.810
myself, can you compare a gravity

408
00:19:11.810 --> 00:19:14.650
wave to a geometrical wave that

409
00:19:14.650 --> 00:19:17.650
is a sinusoidal wave or a sine wave

410
00:19:17.650 --> 00:19:20.090
that's going to have regular minima and

411
00:19:20.090 --> 00:19:23.090
maxima to it? So what do you think of that? Does

412
00:19:23.090 --> 00:19:25.930
that make any sense? Um, and

413
00:19:25.930 --> 00:19:28.850
then if that were the case, I thought,

414
00:19:29.090 --> 00:19:31.730
can two gravity waves interact?

415
00:19:32.850 --> 00:19:35.450
Can they either double their intensity or

416
00:19:35.450 --> 00:19:36.610
nullify each other?

417
00:19:38.210 --> 00:19:41.130
Can they be in phase or out of phase is another way of looking at

418
00:19:41.130 --> 00:19:44.090
it. And then if we want

419
00:19:44.090 --> 00:19:46.930
to continue this classical analogy

420
00:19:47.650 --> 00:19:49.570
of, um, speed is equal,

421
00:19:50.460 --> 00:19:53.240
uh, to wavelength divided by

422
00:19:53.480 --> 00:19:56.480
time. Can one gravity have a

423
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wavelength that, for example, would be one

424
00:19:59.320 --> 00:20:02.240
half that of the others? In other words, you'd have

425
00:20:02.240 --> 00:20:04.280
a sort of phase shifting there, maybe.

426
00:20:05.479 --> 00:20:08.320
I'd love to hear what you think about it. I hope you like the question. Cue

427
00:20:08.320 --> 00:20:11.080
up the good job and stay, uh,

428
00:20:11.280 --> 00:20:13.240
warm down there. Bye now.

429
00:20:13.880 --> 00:20:16.720
Heidi Campo: Well, that was a very nice question. Thank

430
00:20:16.720 --> 00:20:18.600
you so much, Fenton. I will stay warm.

431
00:20:22.150 --> 00:20:25.110
It's nothing but warm here in Houston in the summertime for us.

432
00:20:25.350 --> 00:20:27.990
Professor Fred Watson: Yes, I can imagine. So, Fenton,

433
00:20:27.990 --> 00:20:30.950
that's a, uh, good set of questions. And the answer

434
00:20:30.950 --> 00:20:33.510
to most of your questions in there is yes,

435
00:20:34.180 --> 00:20:37.150
uh, the, um, gravitational

436
00:20:37.150 --> 00:20:39.590
waves, ah, are, uh, waves.

437
00:20:40.470 --> 00:20:43.430
They're basically vibrations of space. Uh,

438
00:20:43.590 --> 00:20:45.970
and you probably know that, um,

439
00:20:46.970 --> 00:20:49.770
the waves that we're normally familiar with, like

440
00:20:49.770 --> 00:20:52.090
sound waves, are what are called longitudinal waves.

441
00:20:53.210 --> 00:20:56.170
The molecules of air move backwards and forwards

442
00:20:56.330 --> 00:20:59.200
as the wave progresses. Whereas, uh,

443
00:20:59.200 --> 00:21:01.770
light waves are transverse, uh, waves.

444
00:21:02.170 --> 00:21:04.490
Which are a vibration of the

445
00:21:04.570 --> 00:21:07.530
magnetic and electric fields, uh, which

446
00:21:07.530 --> 00:21:10.250
are, uh, you know, existent at any given time. So,

447
00:21:10.460 --> 00:21:13.240
uh, they are. They are sinusoidal

448
00:21:13.240 --> 00:21:16.200
is the way you describe them. Gravitational

449
00:21:16.200 --> 00:21:19.040
waves are something different. They're called quadrupole waves.

450
00:21:19.360 --> 00:21:22.240
And they're a bit like sine waves,

451
00:21:22.240 --> 00:21:25.240
but they've got a sort of rotational component to

452
00:21:25.240 --> 00:21:28.240
them as well. So they are not,

453
00:21:28.580 --> 00:21:31.160
um, exactly like, uh, a light

454
00:21:31.160 --> 00:21:34.080
wave. But they are similar, uh, in

455
00:21:34.160 --> 00:21:36.960
broad characteristics. And in particular,

456
00:21:37.520 --> 00:21:40.440
they are similar in that, yes, they can interfere

457
00:21:40.440 --> 00:21:43.040
with one another. That's the phenomenon that you were talking about,

458
00:21:43.490 --> 00:21:46.380
uh, where, uh, light waves can either

459
00:21:46.380 --> 00:21:49.380
cancel out or add. Uh, to give you these,

460
00:21:49.380 --> 00:21:52.180
what we call fringe patterns, uh, gravitational

461
00:21:52.180 --> 00:21:55.020
waves can do that as well. Uh, the quadrupole waves

462
00:21:55.020 --> 00:21:57.980
can interfere with one another. And you're also

463
00:21:57.980 --> 00:21:59.900
right that they come in different

464
00:22:00.460 --> 00:22:03.020
wavelengths. We normally think of it as different

465
00:22:03.020 --> 00:22:05.820
frequencies. Uh, so gravitational waves

466
00:22:05.900 --> 00:22:08.780
caused by different phenomena. Have a

467
00:22:08.780 --> 00:22:11.460
very, very wide, uh, variation in

468
00:22:11.460 --> 00:22:14.220
frequency. Uh, some are, uh, what we call,

469
00:22:14.910 --> 00:22:17.890
uh. Well, let me just tell you the ones

470
00:22:17.890 --> 00:22:20.850
that we've observed so far. And that's because the

471
00:22:20.850 --> 00:22:23.410
particular gravitational wave detectors that we have.

472
00:22:23.570 --> 00:22:26.130
Are tuned effectively to these frequencies.

473
00:22:26.290 --> 00:22:29.170
They're the ones that come from colliding

474
00:22:29.170 --> 00:22:32.010
neutron stars, colliding black holes, all of that sort of thing we were just

475
00:22:32.010 --> 00:22:34.850
talking about a few minutes ago. Uh, and

476
00:22:34.930 --> 00:22:37.850
they are more or less in the, um, audio

477
00:22:37.850 --> 00:22:40.810
frequency spectrum. Uh, so if you amplified

478
00:22:40.810 --> 00:22:43.650
them enough, you could hear them. They're, uh, a few

479
00:22:43.650 --> 00:22:46.550
hundred hertz. One hertz is one cycle

480
00:22:46.550 --> 00:22:49.230
per second. But some of the bigger

481
00:22:49.230 --> 00:22:52.190
phenomena in the universe. And I'm thinking now of things

482
00:22:52.190 --> 00:22:55.150
like the Big Bang or the epoch of inflation

483
00:22:55.150 --> 00:22:57.950
times in the universe when things were very different from what they are

484
00:22:57.950 --> 00:23:00.110
now. They generate what we call

485
00:23:00.430 --> 00:23:03.070
nanohertz waves, where the frequencies,

486
00:23:03.870 --> 00:23:06.210
uh, are, uh, measured in, uh,

487
00:23:06.210 --> 00:23:08.830
billionths of a hertz rather than

488
00:23:09.150 --> 00:23:11.470
a few hundred hertz, uh,

489
00:23:12.530 --> 00:23:15.190
uh, so they would be detected in a

490
00:23:15.190 --> 00:23:18.090
completely different way. And in fact, we think. I think one of the ways of detecting

491
00:23:18.090 --> 00:23:21.050
them might be from the cosmic microwave background

492
00:23:21.050 --> 00:23:23.850
radiation, the flash of the Big Bang that we can still see.

493
00:23:24.330 --> 00:23:26.850
So you're right on the money, uh, with all of those

494
00:23:26.850 --> 00:23:29.530
questions. Yes, gravitational waves do behave

495
00:23:29.850 --> 00:23:32.729
almost in an analogous way to light. They certainly travel at

496
00:23:32.729 --> 00:23:35.650
the same speed of light. They can interfere, and they

497
00:23:35.650 --> 00:23:37.690
do come in widely different frequencies.

498
00:23:38.170 --> 00:23:40.930
Heidi Campo: Well, excellent. Thank you. Thank you so much, Fred. These have

499
00:23:40.930 --> 00:23:43.610
been wonderful answers to some

500
00:23:43.610 --> 00:23:46.290
wonderful questions. And thank you so much to everybody

501
00:23:46.290 --> 00:23:49.270
who has written in. Um, we

502
00:23:49.270 --> 00:23:51.750
really do have some of the best

503
00:23:51.750 --> 00:23:54.630
listeners here. I mean, this podcast, we

504
00:23:54.630 --> 00:23:57.230
have such an amazing, engaged

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audience. I mean, you guys are half of the show, really.

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Your questions are half of the show. Um, so

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please stay curious. Keep sending in

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your wonderful questions. Uh, it's

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certainly so fun for me to hear Fred, um,

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answer them and, ah, it's a good time.

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Um, Fred, do you have anything else you want to say

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before we sign off for today?

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Professor Fred Watson: No, just keep the questions coming in, folks, because this is

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the thing that makes SpaceNut special. We've got such a

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wide audience all over the world. We love

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hearing from you and we cover your questions,

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tricky ones or non tricky ones alike.

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Thank you. And thanks to you, Heidi, too.

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Heidi Campo: Oh, thank you, Fred. You're so sweet.

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All right, well, this has been, um, another Q and A

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episode of Space Nuts. We are,

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00:24:46.010 --> 00:24:47.850
Heidi and Fred, signing off.

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Generic: You've been listening to the Space Nuts podcast,

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00:24:53.490 --> 00:24:56.290
available at Apple Podcasts, Spotify,

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00:24:56.450 --> 00:24:59.210
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00:24:59.210 --> 00:25:00.970
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demand at bitesz.com. This has been another

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00:25:03.970 --> 00:25:06.010
quality podcast production from

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00:25:06.010 --> 00:25:07.170
bitesz.com