Celestial Curiosities: Pulsars, Gravitational Waves & the Secrets of the Universe

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Heidi Campo: Welcome back to another fun and exciting

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Q and A episode of Space Nuts.

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I am your host for this episode, Heidi Campo. And

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joining me is Professor Fred Watson,

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astronomer at large.

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Voice Over Guy: 15 seconds. Guidance is internal.

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10, 9. Ignition

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sequence star 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

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Astronauts report. It feels good.

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Heidi Campo: Fred, how are you on this fine day?

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Professor Fred Watson: I'm very well, thanks, Heidi.

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And, um, I'm, um, delighted to see you again

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because it is always a pleasure to take our, uh, listener

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questions, uh, especially on a nice fine.

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What is here in Australia, Winter's morning?

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Uh, uh, it's a sunny day, as we

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often get in wintertime in Sydney.

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Heidi Campo: Well, you'll be delighted to hear that it has

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finally stopped raining here in Houston, Texas.

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The sun has come back out, starting to forget what it looked

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like. But, um, we will be going

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camping this weekend, so I'm looking forward to that. I

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will, um, report back to you guys next week what, uh, the

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weather from West Texas looks like.

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Professor Fred Watson: If you get any great photos, Heidi, we should try and

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post them on the Space Nuts website.

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Heidi Campo: Oh, maybe I'll have to bring my telescope, uh, and do some

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astrophotography out there. Actually, that's. I'm gonna, I

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am gonna do that.

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Um, and speaking of the United States, all of our

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questions are from the U.S. this, uh,

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this, this go around. And our first question

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comes from dean from Washington,

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D.C. doesn't get any more United States

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than that. Dean asks,

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um, are all neutron stars

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pulsars in? If so, is it not

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theoretically possible that a collapsing star has

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so little angular momentum that it doesn't pulse?

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If not, what else can a neutron

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star be?

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Professor Fred Watson: So, um, yeah, this, this, this

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question has a simple answer. No.

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Um, thank you, Dean.

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Heidi Campo: Moving on.

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Professor Fred Watson: I might elaborate on that a little bit. Um,

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not all neutron stars are pulsars. And actually, look, I'm

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going to take a direct quote from a NASA

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website called Ask an Astrophysicist.

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Doesn't come any better than that. Um,

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because I love the opening of this little

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answer. Most neutron stars in the

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universe are old enough and tired enough

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that they are no longer pulsars.

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Um, and let me just interrupt

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that quote by reminding us what

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a neutron star and a pulsar is. A neutron star

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is this highly collapsed object. It used to be a star,

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but now we're seeing the collapsed core of the star,

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only a few kilometers or miles across.

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Uh, uh, what makes it a pulsar is

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when it's spinning rapidly, uh,

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and beaming radiation from its magnetic Poles.

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So they behave just like a lighthouse, flashing, uh,

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on and off, pulsing, uh, as the name implies.

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So, uh, Dean's question is a good one. Are all

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neutron stars pulsars? And they're not.

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And as the NASA website says,

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most of them are old enough and tired enough that they're no longer

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pulsars. They've stopped spinning. Uh, and

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just one, uh, further sentence on

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that, which I think is quite illuminating. A recent paper

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estimates 1000 million, what we call

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a billion, normally 1000 million old

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neutron stars in our galaxy in. Even though

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the known number of pulsars, uh,

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is only about 1000. So

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there are many, many more neutron stars

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that don't pulsate than there are that do

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just because they've lost all their rotational energy.

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So, a great question from Dean, um, sent

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me to NASA's website, which is always a good thing.

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Heidi Campo: I think they know the right answer.

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Professor Fred Watson: One would hope so. Yeah.

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Heidi Campo: I saw a T shirt in their gift shop a few weeks ago when

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I was there, and it just. The Earth is round. We

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checked. Love NASA.

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I thought that was kind of cute and cheeky.

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Professor Fred Watson: Yeah.

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Heidi Campo: Our next question is from Ben,

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who is actually a new listener. So thank

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you, Ben, for writing in. This is, uh, so much

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fun. Ben says, I came across the

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podcast last week and I've been zooming through

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it. I love the content. Thank you.

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And then Ben goes on to say, I've got a question, and hopefully you

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haven't already answered it on the roughly

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450 episodes I haven't had

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a chance to listen to yet. Um, but he

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says one, when neutron stars and

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or black holes merged to

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produce gravitational waves, they lose mass,

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which gets converted to energy, which

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comprises. Which comprises of the gravitational

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wave. But how does that conversion work?

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Specifically? I'm thinking of a binary

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neutron star system merging,

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since my understanding is that the mass of the

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neutron is quite consistent across the universe.

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A reduction in mass would imply that a

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reduction in the number of neutrons

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would imply a reduction in the number of neutrons.

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If this small leap of logic holds,

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what determines which neutrons get converted

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to energy? Are the faded neutrons

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extracted evenly from throughout the

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merging objects, or is there a region

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that seems to be favored? And what

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does this process of converting neutrons to

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energy look like?

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Ben is curious and hungry for answers.

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Professor Fred Watson: It's a fabulous question, Ben.

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Um, I've got a question for you, Ben, as well. How did you manage to get

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through 450 episodes in

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a week, less than a week? That

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defies, um, probably the laws of physics. I

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Think, uh, but that's all right because

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apparently uh, merging neutron

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stars also apparently derive

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um, they, they break the laws of

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physics. So um,

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Ben, your question, as some of our

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listener questions often do because they are so good,

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sent me to the World Wide Web.

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And the answer to this question is

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quite, uh, it's quite subtle and there's

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several things going on, partly because

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we're dealing with very intense

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gravitational fields. Uh, and

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um, you know, to answer your question, are

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the fated neutrons extracted evenly throughout the

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merging objects or is there a

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region that seems to be favored, um,

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that probably relates to the

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event horizon of the neutron stars because

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they do have event horizons. Um, and

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I don't think I'm capable of answering

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that question. Uh, and

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in any case it's more subtle than

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just um, you know, neutrons getting thrown

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away, uh, than what we were, than what

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your question might imply. So

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I would actually suggest, uh, Ben, that

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you have a look uh, online,

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uh, ah, at the uh, physics.stackink

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exchange.com website,

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uh, because

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physics.stackexchange.com

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has got a uh, very nice set

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of question, question very similar to

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yours and some quite lengthy answers

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that go into some detail, um, and

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look at different aspects of this question.

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Um, so if you Google energy conversion from

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mass to gravitational wave, the, that will take

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you to this website and maybe

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I can just um, you know, talk about

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uh, one of those answers. And that is that

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um, if you imagine, uh,

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uh, one of the sort of subatomic particles and what

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we call an alpha particle, which is the nucleus, a helium

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4 nucleus, got two protons, two

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neutrons, but its mass

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is actually less than the

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sum of those protons and neutrons.

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And that's because there is something called

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binding energy, uh, that's

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released when that particle is

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formed. And so uh, the

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bottom line here is that mass and

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energy are uh, highly interchangeable. When you're

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talking about the kinds of things, the sort of

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extremes that we are looking at in the

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case of um, a neutron star, neutron star

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collisions. Even in a neutron star doing its thing,

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it's still extreme situations. And because

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of the relationship that we're all aware of between

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mass and energy, E equals MC squared.

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That is, uh, why

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you know, you've got this

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potential to transform what looks

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like a mass of a single particle,

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uh, into energy, uh, to result

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in a lower gravitational mass

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for the pair of neutron stars. Sorry, the bottom line

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here, which I should have said at the beginning, is that often when you've

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got this neutron star, neutron star

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collision, uh, you Get a

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gravitational wave which

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essentially, uh, has enough energy

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to account for a difference in mass. It's not

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just the sum of the two neutron stars that come together.

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There is a mass loss as well, which we see as the

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gravitational wave. And this is one of the mechanisms

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that causes that. So have a look Ben, at

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that webpage. Uh, and if you still

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don't get it, ask us again, uh, and

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I'll have another shot at it. But it is a really

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interesting question and a good one too.

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Um, um, got me thinking yesterday. I

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was worrying all day about this

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question, uh, trying to take my mind off the

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root canal treatment that I was having at the dentist. At

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the same time.

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Heidi Campo: I also think of particle, uh, physics while I'm at the dentist.

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Professor Fred Watson: It's the only thing to do really, isn't it?

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Heidi Campo: So I actually, I will give my dentist a shout out.

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My dentist, um, was one of my good friends

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in, uh, doing my undergrad. And it was kind of cute

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because the whole little cohort of us, we

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um, started, we were in a powerlifting club in

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my undergrad and uh,

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we were just, you know, just a bunch of kids. And now he's

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a grown up who's a dentist and we're all doing our

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things. One of the other ones went on to be um,

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a neurosurgeon. And so I'm like, it's quite a

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little brainiac group of strength athletes.

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So shout out to, uh, Dr. Gatlin

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Marks, dentist at Platinum Dentistry

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in Utah. On that's, you know, unprompted.

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Not paid for free advertising, but he's great.

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Professor Fred Watson: Well, I should advertise mine, shouldn't I?

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Nothing like as nice a story, but I won't bother.

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Heidi Campo: Space nuts.

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Um, well, our next question is an audio question

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from Craig and we are going to play that

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question for you right now.

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Professor Fred Watson: Hi professors, it's Craig down in

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sunny Marimbula. Um, I've been

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seeing items about James Webb, uh,

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seeing really massive galaxies

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much bigger than they, than current

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cosmology expects. Are we

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in an older universe? Could we

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tell the difference between a big bang and a supermassive

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white hole that's erupted into an existing space

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time? They're just an uh,

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overactive imagination. I hope you're enjoying your

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week. Ciao.

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Heidi Campo: All right, that was Craig's, uh, question.

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Professor Fred Watson: Craig, the only person asking uh, a

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question this week from.

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Not from the usa.

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Okay, his question about big galaxies,

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is it telling us that the universe is older than we think?

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Maybe, uh, that's a, it's a nice way of Thinking

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about it, um, except that

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we, we still,

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you know, all the evidence points

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to the

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universe having a beginning which

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was 13.8 billion years ago,

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um, which, um, we think was,

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um, the result of a, an event called the Big Bang,

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an explosive event. Uh, we

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believe that's the case partly because of what we observe today.

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But we can also still see the flash of that Big Bang

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by the fact that the light has taken 13.8 billion

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years to get to us. So, um, it's

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very hard to see how, uh,

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if the universe was older than that Big Bang,

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how galaxies would survive that

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explosive event. Um,

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so you know what, um,

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Craig's question is about is,

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uh, are, uh, there galaxies that are older than we think the

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universe is? And

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it defies logic. It's like saying,

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um. And in fact, for a while, this was one of the problems

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with the Big Bang theory. People thought, uh, the

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um, planets,

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uh, stars and atoms were actually older

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than the measurement of the age of the universe that

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we got. And that was one of the problems for the Big Bang theory,

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uh, which was, uh, only really resolved in

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the 60s, 1950s and 60s.

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Um, so

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I think that's still a step of logic that

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we're not prepared to dismiss,

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uh, that yes, there is that, um,

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the Big Bang does mark the start of, uh, the

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formation of galaxies and the galaxies in the

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universe. Um, I have a colleague and uh,

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friend, uh, who's a, uh, very distinguished

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astronomer in the uk, Richard Ellis. And

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he is absolutely. He's a

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cosmologist. He's somebody who looks at the history of the universe,

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very interested in the history of the early universe.

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He is absolutely certain, uh,

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that those galaxies that we can see that

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do look bigger and older than what we expected them to

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be, uh, that they do not defy,

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uh, conventional cosmology, that we can still,

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um, you know, work out

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theoretical models that would allow those galaxies still to

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be young, even though they look more

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advanced in years than we thought they

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would be. So, uh, it's all about

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our understanding of galaxy formation rather than

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having the cosmology wrong, rather than having,

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uh, the age of the universe wrong. So,

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a good suggestion, uh, uh, but I think

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we are still stuck with trying to understand how

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these galaxies got so big so quickly.

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Heidi Campo: And stuck is what it is. Sometimes

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that's what I get excited about with space. There's

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so many questions that have to be answered.

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Other sciences are so defined, but space

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is infinite for us to figure out.

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Professor Fred Watson: Okay, we checked all four systems and.

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Heidi Campo: Dealing with the space nets, our, um,

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our last Question is from another curious

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listener. Mark from Bloomington,

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00:15:58.490 --> 00:16:01.370
Indiana says hello there.

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What might meteors look like to a person on the

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surface of Mars or Venus, if that were possible.

328
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The planets are at uh, extremes of atmospheric

329
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density. But carbon dioxide is the primary

330
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aspheric gas for each.

331
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The primary aspheric gas for each. And there is very little

332
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oxygen present compared to Earth and to

333
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each other. Would meteors appear brighter or dimmer,

334
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different colors travel faster or slower,

335
00:16:28.960 --> 00:16:31.720
more or less likely to be seen given the thick or

336
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thin clouds and the uh, clouds altitudes

337
00:16:34.880 --> 00:16:37.720
more or less likely to strike the surface. Thanks

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for any insights or even guesses.

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Professor Fred Watson: I think we've been sprung here, Heidi. People have realized that we

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just take guesses at these things.

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Um, so it's uh,

342
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it's another great question. You know, we uh, this is,

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I think none of the questions that we've had today have

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ever come in before. Uh, maybe,

345
00:17:01.420 --> 00:17:04.170
maybe people have been speculating about the um,

346
00:17:04.380 --> 00:17:07.220
the mystery of these early galaxies. But this is a

347
00:17:07.220 --> 00:17:10.220
great question. What would meteorites, sorry, what would meteors

348
00:17:10.780 --> 00:17:13.660
look like, uh, to somebody. Let's

349
00:17:13.660 --> 00:17:16.579
just stick with Mars for now because that's the easier

350
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one to deal with. I um, think Venus will

351
00:17:19.499 --> 00:17:22.310
be a problem because the atmosphere is so thick, uh,

352
00:17:22.579 --> 00:17:25.059
so opaque that uh, you probably wouldn't see any

353
00:17:25.059 --> 00:17:26.739
meteors at all just because,

354
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you know, there's very little transparency in the

355
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atmosphere. Mars however, is different. Uh,

356
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it does have clouds, but not as many as we have here on

357
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Earth. Uh, let's get to the easy

358
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question, the easy part of this question, uh,

359
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which is, um,

360
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Query. Are they more or less likely to

361
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strike the surface? And the answer is they're more likely

362
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because Mars's atmosphere is much thinner. It's less than

363
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1% of the pressure of the Earth's atmosphere. That

364
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means that um, it's uh, more likely

365
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that a meteoritic object would

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survive its passage through the atmosphere to

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reach the ground. Um, and we do find

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meteorites on Mars. There are many examples that the

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uh, various Mars rovers have found meteorites on

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the planet Mars. A uh, meteorite is

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a meteor that's got as far as landing on the, on the

372
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ground, but what they would look like in

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the uh, in the sky, uh,

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uh, doesn't really have that much to do with what the

375
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constituents of the atmosphere are. Uh,

376
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uh, because what you see when you see a

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meteor, a shooting star is the fact

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that it is simply um,

379
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it's being um, heated up to

380
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incandescence. It's not burning in the

381
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sense that things burn

382
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in the presence of oxygen. Uh, and that I think is the

383
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thrust of, uh, Mark's question.

384
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But what you're seeing is this thing shooting through the

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atmosphere. It is meeting a gas. Uh,

386
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the gas is providing some resistance, but

387
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also a lot of friction on the outside of this

388
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particle or stone or rock or baseball, whatever

389
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it is that's coming in, uh, whatever size it is that's coming,

390
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coming in. And that's what causes the brightness

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of the meteorites being flashed into

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incandescence by its speed rather than a

393
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chemical reaction taking place. Um, that

394
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would, um, make uh, that much difference. Although

395
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certainly we do see evidence of the oxygen

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in the light of some of these. So meteors on

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Mars would look similar to what they do on

398
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Earth. There's some dispute

399
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because the atmosphere of Mars, whilst

400
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it's also much thinner than Earth's atmosphere, is

401
00:19:41.830 --> 00:19:44.500
distributed differently. You know, uh,

402
00:19:45.030 --> 00:19:47.950
the way in which it falls off in pressure as you go

403
00:19:47.950 --> 00:19:50.950
up in height, uh, is different from

404
00:19:50.950 --> 00:19:53.790
what it is on Earth. So that might mean that the

405
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height at which meteors start to glow

406
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as they come through the surface, sorry, come through

407
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the atmosphere of Mars might be different.

408
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And if they were lower, if they were burning up lower down

409
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in the atmosphere, then they would look a bit brighter than they

410
00:20:08.600 --> 00:20:11.280
do here on Earth. If they were burning up higher in the

411
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atmosphere, they would, uh, look a bit

412
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fainter. And it's not quite clear which of those

413
00:20:16.920 --> 00:20:19.840
is the case. Uh, there's some dispute among

414
00:20:20.000 --> 00:20:23.000
the. Certainly the things I've read about whether they

415
00:20:23.000 --> 00:20:25.840
will be brighter or fainter, but they will be much the same.

416
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So, uh, we hope that maybe one

417
00:20:29.360 --> 00:20:32.270
day when, uh, astronauts are

418
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exploring, uh, but not colonizing

419
00:20:35.550 --> 00:20:38.430
Mars, uh, that they might send us

420
00:20:38.430 --> 00:20:41.390
back reports of meteors that they've seen in the night skies of

421
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Mars. And maybe you'll hear about it on Space notes.

422
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Heidi Campo: Maybe so. And it is my understanding that that

423
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is one. I mean, there's so many concerns with Moon

424
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to Mars missions. And a potential Mars colony

425
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is it's not as safe. Our atmosphere does

426
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surprisingly a lot to protect us. And that is,

427
00:21:00.040 --> 00:21:02.580
um, in a lot of student design

428
00:21:02.740 --> 00:21:05.540
competitions that is something they're really

429
00:21:05.540 --> 00:21:08.460
asking for students to look at is, hey, how can we

430
00:21:08.460 --> 00:21:11.340
protect potential analogs

431
00:21:11.340 --> 00:21:14.220
or colonies or any other assets we put

432
00:21:14.220 --> 00:21:16.740
on Mars? How do we protect those from these

433
00:21:16.820 --> 00:21:19.700
constant, um, impacts? And

434
00:21:19.890 --> 00:21:22.740
ah, that is really kind of an interesting question right now.

435
00:21:22.740 --> 00:21:25.290
And that's not really my wheelhouse. But, um,

436
00:21:25.460 --> 00:21:27.980
people in the engineering world are, um.

437
00:21:28.530 --> 00:21:30.930
There's a lot of fun things for them. To do with those

438
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projects.

439
00:21:32.930 --> 00:21:35.890
Professor Fred Watson: Indeed. That's right. Look, it's a different world

440
00:21:35.890 --> 00:21:38.730
from ours. Everything's

441
00:21:38.730 --> 00:21:41.290
different. Uh, radiation, meteoritic

442
00:21:41.290 --> 00:21:44.290
bombardment, all of those things. Low pressure, low gravity,

443
00:21:45.250 --> 00:21:48.010
different world and a lot to think about if

444
00:21:48.010 --> 00:21:51.010
we are ever going to have humans walking on Mars.

445
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Heidi Campo: All right, Fred. Well, ah, this has been

446
00:21:55.770 --> 00:21:58.660
another fantastic Q and A episode. I

447
00:21:58.660 --> 00:22:01.540
always, I love the way you answer these questions. I

448
00:22:01.540 --> 00:22:04.020
feel like, uh, every time we write in,

449
00:22:04.260 --> 00:22:07.140
I feel like each one of us has an opportunity

450
00:22:07.140 --> 00:22:09.620
to be a, uh, collaborator with you and

451
00:22:09.860 --> 00:22:12.820
gets to experience what it's like to be on

452
00:22:12.820 --> 00:22:15.540
this intellectual journey together. So keep

453
00:22:15.540 --> 00:22:18.420
sending in your amazing questions. You guys are,

454
00:22:18.740 --> 00:22:21.540
you guys are half of the brilliance of this show. So

455
00:22:21.540 --> 00:22:22.340
thank you so much.

456
00:22:22.580 --> 00:22:24.790
Professor Fred Watson: That's right. I agree there

457
00:22:24.790 --> 00:22:27.710
wholeheartedly, Heidi. At least half. In fact, maybe more than

458
00:22:27.710 --> 00:22:28.030
that.

459
00:22:30.110 --> 00:22:33.030
Heidi Campo: Excellent. Well, thank you everybody to listening to

460
00:22:33.030 --> 00:22:36.030
another episode of Space Nuts. We will catch

461
00:22:36.030 --> 00:22:37.150
you next time.

462
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Professor Fred Watson: Sounds great. Thanks again, Heidi.

463
00:22:40.190 --> 00:22:42.430
Andrew Dunkley: Hi, Fred. Hi, Huw. Hi,

464
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Heidi.

465
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It's Andrew from the southwestern

466
00:22:46.150 --> 00:22:49.030
Indian Ocean. We've just finished a seven day crossing

467
00:22:49.260 --> 00:22:51.900
of the Indian Ocean and stopped yesterday at

468
00:22:52.060 --> 00:22:54.420
the beautiful island country of

469
00:22:54.420 --> 00:22:57.380
Mauritius. And it's winter there, but

470
00:22:57.380 --> 00:22:59.660
the temperature was in the

471
00:22:59.810 --> 00:23:02.540
uh, mid to high 20s. So,

472
00:23:02.590 --> 00:23:05.500
um, yeah, if that's winter, I'll take it. It's been

473
00:23:05.500 --> 00:23:08.150
beautiful. The seas were quite smooth after our, uh,

474
00:23:08.150 --> 00:23:11.140
treacherous rounding of south, uh, southern

475
00:23:11.140 --> 00:23:13.940
Australia. Uh, but now that we've left Mauritius,

476
00:23:13.940 --> 00:23:16.310
we're heading into, into some heavy seas as we

477
00:23:16.950 --> 00:23:19.710
move towards the Cape of Good Hope and

478
00:23:19.710 --> 00:23:22.470
then come up the other side of Africa. But

479
00:23:22.470 --> 00:23:25.090
Mauritius was absolutely beautiful, lovely, uh,

480
00:23:25.470 --> 00:23:27.750
people, interesting story behind Mauritius.

481
00:23:28.230 --> 00:23:30.949
It's a, an island that was discovered by

482
00:23:31.350 --> 00:23:34.230
Arabian, uh, sailors. Uh, it was unoccupied,

483
00:23:34.230 --> 00:23:37.230
so they moved in and uh, of course they brought their

484
00:23:37.230 --> 00:23:40.190
slaves with them. Um, somewhere along the

485
00:23:40.190 --> 00:23:43.130
line they handed us over to, um,

486
00:23:43.130 --> 00:23:46.000
the Dutch and the Portuguese. Uh, the

487
00:23:46.000 --> 00:23:48.840
Dutch kind of decimated everything they possibly

488
00:23:48.840 --> 00:23:51.760
could. My wife's half Dutch, so I've got

489
00:23:51.760 --> 00:23:54.400
to be careful what I say. But, uh, they killed off the

490
00:23:54.400 --> 00:23:57.040
dodo bird, they destroyed most of the

491
00:23:57.040 --> 00:23:59.640
forests. Uh, they killed off the

492
00:23:59.960 --> 00:24:02.560
native giant turtles. Uh,

493
00:24:02.840 --> 00:24:05.800
so, um, yeah, nothing like that is there today.

494
00:24:05.800 --> 00:24:08.670
But then, uh, the French moved in and they

495
00:24:08.670 --> 00:24:11.630
stayed there for a very long time until they were tipped out by the British.

496
00:24:11.630 --> 00:24:14.430
And the British held sovereignty over Mauritius until

497
00:24:14.430 --> 00:24:17.310
independence late last century. Beautiful

498
00:24:17.310 --> 00:24:20.110
country, very rugged volcanic

499
00:24:20.110 --> 00:24:23.010
landscape. Uh, saw, uh,

500
00:24:23.190 --> 00:24:25.910
the volcano at the top that still, uh, exists. It's

501
00:24:25.910 --> 00:24:28.910
dormant. It hasn't erupted for a long, long time. And I hope it doesn't because

502
00:24:28.910 --> 00:24:31.770
it's got houses all over it. Uh, but, um,

503
00:24:31.790 --> 00:24:34.550
just a, just a beautiful landscape. They speak French

504
00:24:35.190 --> 00:24:38.070
and English as their predominant, uh, languages.

505
00:24:38.070 --> 00:24:41.070
But the, but the, the native people who are originally, uh,

506
00:24:41.830 --> 00:24:44.790
you know, from the slaves of South Africa speak

507
00:24:44.790 --> 00:24:47.350
French Creole. So it's really, really

508
00:24:47.350 --> 00:24:50.350
interesting mix of people. But, uh, a lovely country

509
00:24:50.350 --> 00:24:53.150
and, and very, very much worth

510
00:24:53.150 --> 00:24:55.830
visiting. Uh, and a very big Hindu

511
00:24:56.070 --> 00:24:58.950
population as well. And so we

512
00:24:59.030 --> 00:25:01.960
visited, visited a Hindu temple and the sacred waters

513
00:25:01.960 --> 00:25:04.800
that were discovered by a Hindu many, many years ago,

514
00:25:05.510 --> 00:25:08.170
uh, where people were blessing children and uh,

515
00:25:09.120 --> 00:25:11.880
walking through the waters, which are just as sacred as the

516
00:25:11.880 --> 00:25:14.650
Ganges, apparently. Uh, and um,

517
00:25:14.720 --> 00:25:17.640
there was a little monument there to the sun

518
00:25:17.640 --> 00:25:20.560
and the planets. So, uh, there was a little

519
00:25:20.800 --> 00:25:22.560
astronomical connection,

520
00:25:23.410 --> 00:25:24.720
uh, while I was there.

521
00:25:24.970 --> 00:25:27.650
Anyway, that's where we're up to. Next stop will be

522
00:25:27.650 --> 00:25:30.610
Cape Town. It's going to take us five days of sailing to get

523
00:25:30.610 --> 00:25:32.810
there, so I'll report on that next time.

524
00:25:33.610 --> 00:25:36.330
So hope all is going well with Space Nuts. See you soon.

525
00:25:37.530 --> 00:25:40.330
Professor Fred Watson: You've been listening to the Space Nuts. Podcast,

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00:25:41.930 --> 00:25:44.650
available at Apple Podcasts, Spotify,

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00:25:44.890 --> 00:25:47.650
iHeartRadio or your favorite podcast

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00:25:47.650 --> 00:25:50.350
player. You can also stream on demand at bitesz.com

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00:25:51.540 --> 00:25:54.340
This has been another quality podcast production from

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00:25:54.340 --> 00:25:55.060
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