Megastructures, Exoplanet Myths & Satellite Showers: #495 - The Quipu Conundrum and More | Space...

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Language: en

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hi there thanks for joining us this is


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Space Nuts Andrew Dunley here good to


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have your company and on this episode we


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have a lot to talk about uh the first


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thing will be a mega structure of Epic


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Proportions discovered in the universe


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now this is not a a something that was


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manufactured by some incredible race uh


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because we have talked about me mega


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structures in the past now this is


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natural and it's called


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kipo what's that mean we'll tell you


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soon um this is uh one of um the biggest


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bug bears that jonty has to deal with


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the overselling of the potential for


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life on exoplanets yes there is one in


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the news at the moment we'll do an


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update on 2024


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yr4 the odds of it hitting us have hared


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and SpaceX satellites raining down on


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our atmosphere uh what does that mean


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we'll tell you on this episode of Space


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Nuts 15 seconds guidance is internal 10


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nine ignition sequence start Space Nuts


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5 4 3 2 1 2 3 4 5 5 3 Space Nuts as the


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report it feels good and he's back again


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surprisingly it's Johny Horner professor


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of a physics at the University of


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Southern Queensland jonty hello good day


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how are you going I am well how are you


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I'm getting there I've never got the


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hang of mornings I think I'm a bit like


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um the characters from The Hitchhikers


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Guide except for me it's mornings it's


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not Mondays it's mornings yes I I used


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to be like that and then I started in


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breakfast radio and did it for 30 years


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so I eventually got used to being up at


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sparrows the breakfast shift does not


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sound fun uh I enjoyed it but that was


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just me I don't know if anyone else did


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especially the audience boom


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boom all right uh let us get into it and


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we're going to start off with this um


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discovery of a of a mega structure which


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is uh been uh in the news over the last


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week or so and it's it's called kipo


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we'll explain why it's called that soon


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but this is a a mega structure uh of


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natural formation in the universe the


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enormity of this is mind splitting


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amazing yes yes it is it's one of those


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things that just makes your head hurt


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like a lot of things in cosmology now


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I'll happily hold my hands up right at


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the start and say my expertise is on the


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parts of the University what closer than


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this so I'm not a cosmologist and if


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there are cosmologists listening you


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know people who are cosmology


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enthusiasts I might get something wrong


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please don't be too critical um because


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you know the the size of the things that


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I don't know in cosmology is enormous um


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just like the subject itself but this is


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a really interesting one when we think


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about the universe you see all these


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wonderful simulations that come out of


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our models of how the universe works


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that people produce all the time and you


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know you can almost see videos on


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fabulous documentary Series where they


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start at the scale of an atom and keep


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zooming out and you eventually get to


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the person and keep zooming out and the


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scale of cosmology is roughly the same


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scale compared to a human being that a


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human being is compared to an atom so


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that's the kind of size scale we're


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talking about here which is the study of


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the ridiculously big but as you zoom out


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from that human being on the earth you


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get the solar system then you get the


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local stars then you get our galaxy and


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then as move out you get structures of


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galaxies together so you get small


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clusters of galaxies and those small


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clusters hang together in bigger


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clusters that gather together in super


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clusters and they for a long time were


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kind of the biggest structures we saw in


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the universe but then as you zoom out


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further you start seeing these


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structures like walls and filaments


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where those clusters and super clusters


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of galaxies are themselves forming


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structures with huge voids in between so


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on this kind of scale when you see those


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simulations it looks almost like a view


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of a sponge so you if you've had a a


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sponge in your bath the sponge is a lot


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of open air spaces surrounded by lots of


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solid material and all the solid


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material is in contact with all the


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solid material but all the air is in


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contact with all the air so you could


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put a bit of string and go all the way


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through the sponge through the air holes


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and come out the other side and that's


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kind of what this view of the universe


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looks like it these long filaments and


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walls all connected to one another with


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these enormous voids of empty space


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between them that's the context we're


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talking about here so the team of


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researchers who studied this have been


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carrying out observations using an x-ray


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survey looking at very high energy


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electromagnetic radiation that's


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produced from incredibly hot gas in the


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most massive clusters of galaxies


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enormous structures themselves and


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they've looked at a region about 250


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million Parx across in all directions


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maybe a bit


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more looking for the biggest structures


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they can find in that region and they've


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identified four of these what they're


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calling super structures and they super


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structures are Mega structures because


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they are bigger than normal structures


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they structures made of structures made


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of superclusters made of clusters made


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of local clusters made of galaxies on we


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go all the way down again now these four


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structures that they found between them


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contain 45% of all the Galaxy clusters


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they could see 30% of all the galaxies


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and 25% of all the matter but they only


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occupy about 133% of the volume so that


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gives you the idea of lots of empty


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space with these filaments around it the


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biggest of these this is someone Keo


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that's getting all the attention it's


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ridiculous they talk about it being 200


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quadrillion times the mass of the Sun so


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if you remember fistas in countries that


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do things differently we using the kind


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of British scale Mill million billion


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system here so a million is 10 to the 6


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one with 6 zeros after it a billion is a


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th million so that's 10 to the N9 a


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trillion is a, billion or a million


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million that's 10 the 12 a quadrillion


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is a, trillion or a million billion or a


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billion million so it's 10 to the 15 200


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of those means this is 2 * 10 to the 17


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or two with 17 zeros after it times the


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mass of the Sun now that's a number that


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is bound to make your head hurt so I


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converted that down by looking at how


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many milky wees that would be and that


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be something like


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130,000 times the mass of our


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galaxy so stupidly big numbers it is


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spread over a distance it's a big long


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feature about 400 MEAP parex long so one


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Parc is perversely the distance that an


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object would be away from the Earth if


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it's Parallax as the earth goes around


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the Sun was 1 out second it's a really


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obscure unit of measurement it makes


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sense when you're doing the maths of


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measuring distance but it's not


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particularly user friendly it's a bit


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like talking in feet light years is a


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bit like talking in meters same kind of


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thing most people find light years more


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straightforward to visualize where one


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lightyear is the time it takes light to


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travel in one year and there are 3.26


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light years in one Parc so 400 megga


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passet is 1.3 billion light years long


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so in other words light leaving one end


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of this structure would take 1.3 billion


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years or 1,300 million years to go from


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one end to the other so it's an enormous


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enormous


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structure now that's all well and good


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and it's fabulous cataloging the biggest


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and the most massive and the brightest


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and I know a lot of people I do this


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occasionally look up Wikipedia articles


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like what's a as massive star what's a


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as luminous star things like that yeah


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but it's also really valuable to know


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this kind of stuff because if you study


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these big structures that gives us


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information that we can compare to the


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models that are based on our current


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understanding of the universe to see if


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those models make sense and the good


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thing is that the current models of how


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the universe work predict structures


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like this so this is very much in line


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with what people expected to see and


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that's a really good part of how science


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works you know it's very much Cas of our


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models predicted this and now you've


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seen it that makes us happy because it


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means the models are working correctly


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it also is the kind of information


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that's really useful for people studying


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the big bang and more ancient Universe


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because structures like this are


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sufficiently massive that they will


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influence our view of what is beyond you


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get gravitational lensing from the big


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objects you also even get and I don't


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fully understand how this works but you


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also get the pollution of the cosmic


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microwave background which is the last


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hit of the Big Bang it's the it's our


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image of the last surface 300,000 years


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after the big bang where the universe


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became


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transparent and we found little bits of


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structure in that which are important


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for us understanding how the modern


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structure of the universe formed but


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that structure is polluted by the


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influence of these


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foreground objects by something called


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the integrated sax wolf effect I've no


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idea how that works to be brutally


00:09:25.079 --> 00:09:28.550
honest but if you've got something like


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that that pollutes view of what's beyond


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and we want to understand what's beyond


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the better we can see the foreground the


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better we can account for it when we're


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subing the background so getting studies


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of this a it's fascinating it's a really


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good test for our models but it also


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allows us in the future to get a better


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handle on how things like the cosmic


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microwave background really look when


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you filter out the foreground mess and I


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guess the equivalent here would be like


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having a light pollution filter for


00:09:56.680 --> 00:09:58.750
people who are astronomy photography


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enesi gas you've got a murky light


00:10:01.120 --> 00:10:02.590
polluted sky but if you put a light


00:10:02.600 --> 00:10:03.990
pollution filter on the front of your


00:10:04.000 --> 00:10:06.310
lens you can cancel out that foreground


00:10:06.320 --> 00:10:07.829
mess and get a much better view of


00:10:07.839 --> 00:10:10.630
what's beyond this will enable us to do


00:10:10.640 --> 00:10:12.230
that same kind of filtering when we're


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looking at the microwave background so I


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think it's a fabulous Story full of


00:10:16.760 --> 00:10:20.030
numbers what make your head hurt quite


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they're massive numbers they just uh


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just incredible


00:10:24.360 --> 00:10:26.710
now why is it called


00:10:26.720 --> 00:10:29.509
Keo this is partially because of the


00:10:29.519 --> 00:10:31.430
structure so it looks like a long thick


00:10:31.440 --> 00:10:32.949
filament with thinner filaments


00:10:32.959 --> 00:10:35.389
branching off the sides of it and the


00:10:35.399 --> 00:10:37.829
authors of this paper notice that this


00:10:37.839 --> 00:10:40.190
looks very similar to the traditional


00:10:40.200 --> 00:10:41.990
counting instrument of the Incan people


00:10:42.000 --> 00:10:44.629
in Peru um which was essentially they


00:10:44.639 --> 00:10:47.069
did their counting using knotted ropes


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and that knotted rope counting device


00:10:48.800 --> 00:10:51.389
was a Keo so it's quite a nice nod to


00:10:51.399 --> 00:10:53.829
the traditional culture of the that area


00:10:53.839 --> 00:10:56.430
in Peru again I'm not an anthropologist


00:10:56.440 --> 00:10:58.069
or an archaeologist I don't really know


00:10:58.079 --> 00:11:00.069
much more about it than that but I think


00:11:00.079 --> 00:11:02.710
it is a really nice nod to a different


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culture and as we've talked about in


00:11:04.959 --> 00:11:06.870
previous weeks this idea of embracing


00:11:06.880 --> 00:11:08.230
all the cultures of the Earth in our


00:11:08.240 --> 00:11:09.990
studies going forward it's really


00:11:10.000 --> 00:11:11.710
gaining traction is a really nice way of


00:11:11.720 --> 00:11:14.230
doing things I think absolutely yes I'd


00:11:14.240 --> 00:11:17.910
agree and the the Incans have a um


00:11:17.920 --> 00:11:21.069
strong history with astronomy so uh that


00:11:21.079 --> 00:11:24.670
ties in well too so yeah fascinating uh


00:11:24.680 --> 00:11:26.629
if you would like to chase up that story


00:11:26.639 --> 00:11:28.350
it was published in astronomy and


00:11:28.360 --> 00:11:30.710
astrophysics the journal you can also


00:11:30.720 --> 00:11:34.949
read about it at the archive.org website


00:11:34.959 --> 00:11:38.190
that's arxiv I learned that last week


00:11:38.200 --> 00:11:39.829
archive.org


00:11:39.839 --> 00:11:43.190
uh yes there was some um a lot of


00:11:43.200 --> 00:11:45.949
involvement from the max plank Institute


00:11:45.959 --> 00:11:49.629
in um in running this the author was H


00:11:49.639 --> 00:11:51.870
boringer so uh you might want to look


00:11:51.880 --> 00:11:55.590
that


00:11:55.600 --> 00:11:59.430
up Space Nuts uh now uh let's move on on


00:11:59.440 --> 00:12:02.550
to our next story this is a pet peeve


00:12:02.560 --> 00:12:05.030
story um which Johny wanted to talk


00:12:05.040 --> 00:12:07.949
about and look I'm not surprised that it


00:12:07.959 --> 00:12:11.629
uh it bothers some people uh because I I


00:12:11.639 --> 00:12:14.389
have often referred to the popular press


00:12:14.399 --> 00:12:16.590
when doing this podcast and how they


00:12:16.600 --> 00:12:19.110
latch onto something that isn't quite


00:12:19.120 --> 00:12:21.829
the story but it makes a great headline


00:12:21.839 --> 00:12:24.110
and that's what this is overselling the


00:12:24.120 --> 00:12:26.389
potential for life on


00:12:26.399 --> 00:12:28.750
exoplanets yeah it's and one in


00:12:28.760 --> 00:12:30.230
particular in the news at the moment


00:12:30.240 --> 00:12:31.629
well it's something that's niggled at me


00:12:31.639 --> 00:12:33.350
for a while it should be said that the


00:12:33.360 --> 00:12:35.069
criticism here is not of the research


00:12:35.079 --> 00:12:36.470
done by these authors have done a


00:12:36.480 --> 00:12:37.949
fabulous bit of research and if you look


00:12:37.959 --> 00:12:40.069
at the paper they've got the balance


00:12:40.079 --> 00:12:43.269
right that's fine but there is a very


00:12:43.279 --> 00:12:44.990
common Trend particularly among press


00:12:45.000 --> 00:12:48.590
officers at universities and also around


00:12:48.600 --> 00:12:50.550
a lot of media sites that rely on clicks


00:12:50.560 --> 00:12:54.750
for their income to talk about the most


00:12:54.760 --> 00:12:56.590
habitable planet ever discovered we


00:12:56.600 --> 00:12:58.670
found the most earthlike planet ever and


00:12:58.680 --> 00:13:00.590
the report on this planet are not quite


00:13:00.600 --> 00:13:01.910
that bad but they have been talking


00:13:01.920 --> 00:13:03.990
about potentially habitable planet


00:13:04.000 --> 00:13:06.110
discovered around nearby star because


00:13:06.120 --> 00:13:08.629
that gets a clicks and before we dig


00:13:08.639 --> 00:13:10.150
into this story the reason that this


00:13:10.160 --> 00:13:12.710
niggles at me is that people are getting


00:13:12.720 --> 00:13:15.790
ex exoe fatigue and also lifei SAR


00:13:15.800 --> 00:13:19.430
fatigue so by reporting things when we


00:13:19.440 --> 00:13:20.870
haven't actually found what the reports


00:13:20.880 --> 00:13:22.790
are saying it creates this opinion that


00:13:22.800 --> 00:13:24.829
the science is already done we've


00:13:24.839 --> 00:13:26.629
already discovered the a stuff so when


00:13:26.639 --> 00:13:28.470
we finally find a planet that really


00:13:28.480 --> 00:13:30.430
does have life on it or when we finally


00:13:30.440 --> 00:13:32.990
find a planet that genuinely is Earth


00:13:33.000 --> 00:13:35.430
2.0 that'll be exciting I'll be thrilled


00:13:35.440 --> 00:13:36.550
we've finally got something to talk


00:13:36.560 --> 00:13:38.030
about and everybody will be kind of the


00:13:38.040 --> 00:13:39.590
boy who cried wolf well you've told us


00:13:39.600 --> 00:13:41.750
you've done this a million times already


00:13:41.760 --> 00:13:43.189
yeah and it's easy why are you


00:13:43.199 --> 00:13:46.509
interested you know it's


00:13:46.519 --> 00:13:49.230
also the fact that we basically don't


00:13:49.240 --> 00:13:50.990
know enough to make these statements yet


00:13:51.000 --> 00:13:53.230
so when you see a headline like we found


00:13:53.240 --> 00:13:55.949
the most earthlike planet ever what it's


00:13:55.959 --> 00:13:57.389
actually telling you is we found a


00:13:57.399 --> 00:13:59.189
planet that's about the same diameter as


00:13:59.199 --> 00:14:02.389
the Earth and that's it so it's like me


00:14:02.399 --> 00:14:04.470
being an alien and visiting the Earth


00:14:04.480 --> 00:14:06.110
and scanning the oceans and saying I


00:14:06.120 --> 00:14:07.870
found the most humanlike creature ever


00:14:07.880 --> 00:14:09.189
it's about the same length and it's


00:14:09.199 --> 00:14:10.590
about the same weight and it's about the


00:14:10.600 --> 00:14:13.509
same size it's called a dolphin it's


00:14:13.519 --> 00:14:15.389
nothing like a human whatsoever but it's


00:14:15.399 --> 00:14:17.389
about the same size and about the same


00:14:17.399 --> 00:14:20.030
mass so it's the most humanlike animal


00:14:20.040 --> 00:14:22.629
ever so I get a bit grumpy and there's a


00:14:22.639 --> 00:14:24.310
lot that goes inh habitability that I


00:14:24.320 --> 00:14:26.829
can talk about a little bit later on


00:14:26.839 --> 00:14:28.350
which is why I think this is a much more


00:14:28.360 --> 00:14:30.030
complex problem and that for me that


00:14:30.040 --> 00:14:31.629
makes it much more interesting a lot


00:14:31.639 --> 00:14:33.870
more research to do but it does mean


00:14:33.880 --> 00:14:35.230
that when you get a claim saying


00:14:35.240 --> 00:14:37.110
potentially habitable planet or the most


00:14:37.120 --> 00:14:39.590
habitable planet we've ever found yet


00:14:39.600 --> 00:14:41.110
people even publishing articles about


00:14:41.120 --> 00:14:42.670
super habitable planets that are more


00:14:42.680 --> 00:14:44.829
suitable for life than Earth I don't


00:14:44.839 --> 00:14:47.790
think you can say any of that aha in


00:14:47.800 --> 00:14:49.150
this particular case it is an


00:14:49.160 --> 00:14:51.389
interesting story there is a star called


00:14:51.399 --> 00:14:54.150
82 udani which also goes by the name


00:14:54.160 --> 00:14:58.030
hd20 794 you know astronomers love our


00:14:58.040 --> 00:15:00.910
acronyms in our bar curs this is a star


00:15:00.920 --> 00:15:02.310
that you can see with an AK in the


00:15:02.320 --> 00:15:03.949
constellation of aridus but it's not


00:15:03.959 --> 00:15:05.509
particularly bright it's about magnitude


00:15:05.519 --> 00:15:08.110
4 4 and a half and for a while we've


00:15:08.120 --> 00:15:10.150
known it had two planets around it but


00:15:10.160 --> 00:15:12.870
it's been monitored by the high accuracy


00:15:12.880 --> 00:15:14.430
radial velocity Planet Searcher


00:15:14.440 --> 00:15:17.550
spectrograph Harps in chil and harps is


00:15:17.560 --> 00:15:19.030
an incredible


00:15:19.040 --> 00:15:21.590
instrument it allows you to measure the


00:15:21.600 --> 00:15:24.470
velocity of a star so you take the light


00:15:24.480 --> 00:15:26.189
from a star you break it up into its


00:15:26.199 --> 00:15:28.550
component colors and La across that


00:15:28.560 --> 00:15:31.590
Spectrum is a series of dark lines and


00:15:31.600 --> 00:15:32.790
those dark lines which we call the


00:15:32.800 --> 00:15:35.150
fronhofer absorption lines are the


00:15:35.160 --> 00:15:37.150
fingerprint of all the different atoms


00:15:37.160 --> 00:15:38.829
and molecules in the Stars outer


00:15:38.839 --> 00:15:41.110
atmosphere every Atomic species every


00:15:41.120 --> 00:15:43.590
molecular species absorbs like a very


00:15:43.600 --> 00:15:45.910
specific unique set of wave lengths and


00:15:45.920 --> 00:15:47.870
it imprints this dark set of lines


00:15:47.880 --> 00:15:50.110
across the star Spectrum now if the


00:15:50.120 --> 00:15:52.189
stars moving towards us its light will


00:15:52.199 --> 00:15:54.389
be blue shifted so all of those lines


00:15:54.399 --> 00:15:55.749
will move a little bit to the blue


00:15:55.759 --> 00:15:57.509
because of the dopper effect if it's


00:15:57.519 --> 00:15:59.069
moving away from us the light will be


00:15:59.079 --> 00:16:00.670
red shifted so it'll move a bit to the


00:16:00.680 --> 00:16:03.069
red again with a Doppler effect and I've


00:16:03.079 --> 00:16:04.790
talked about this before this is the


00:16:04.800 --> 00:16:06.430
equivalent of having the tyum coming


00:16:06.440 --> 00:16:08.870
towards you and hearing it high pitched


00:16:08.880 --> 00:16:11.949
and fast with n no and then it moving


00:16:11.959 --> 00:16:13.350
away and you're hearing it low pitched


00:16:13.360 --> 00:16:16.670
and slow with n noo to do with the waves


00:16:16.680 --> 00:16:19.069
getting stretched or compressed


00:16:19.079 --> 00:16:21.389
essentially now what that means is if we


00:16:21.399 --> 00:16:22.949
measure the positiony of these lines


00:16:22.959 --> 00:16:24.309
accurately enough we can measure the


00:16:24.319 --> 00:16:26.030
change in the speed of the Star as it


00:16:26.040 --> 00:16:29.030
moves around by seeing those lines move


00:16:29.040 --> 00:16:30.870
so we can look at stars and see them


00:16:30.880 --> 00:16:32.590
wobbling and INF further presence of


00:16:32.600 --> 00:16:34.910
planets that we can't see by how those


00:16:34.920 --> 00:16:37.509
planets pull those Stars around but


00:16:37.519 --> 00:16:38.790
there are limits to this there's a lot


00:16:38.800 --> 00:16:41.350
of challenges involved so facility like


00:16:41.360 --> 00:16:42.670
the one we've got at the University of


00:16:42.680 --> 00:16:44.629
Southern Queensland which is actually


00:16:44.639 --> 00:16:46.470
the southern hemisphere's only dedicated


00:16:46.480 --> 00:16:49.870
EXO Planet search facility we can get an


00:16:49.880 --> 00:16:51.509
accuracy where we can measure the wobble


00:16:51.519 --> 00:16:54.629
of stars down to about 2 or 3 m a second


00:16:54.639 --> 00:16:57.230
so we could see a star changing in speed


00:16:57.240 --> 00:16:59.269
by about as much as someone going a very


00:16:59.279 --> 00:17:00.189
gentle


00:17:00.199 --> 00:17:03.150
job what that means is we could not find


00:17:03.160 --> 00:17:04.829
these particular planets they're just


00:17:04.839 --> 00:17:07.429
much too hard but the harp spectrograph


00:17:07.439 --> 00:17:10.350
is on a much bigger telescope in a much


00:17:10.360 --> 00:17:12.470
better location and it's an incredibly


00:17:12.480 --> 00:17:15.150
accurate piece of Kit so it lets you get


00:17:15.160 --> 00:17:18.230
down to submeter per second measurements


00:17:18.240 --> 00:17:20.150
which is breathtaking put that in


00:17:20.160 --> 00:17:22.189
perspective we're looking at stars here


00:17:22.199 --> 00:17:24.949
whose distances are quadrillions of


00:17:24.959 --> 00:17:26.669
kilometers away again using the units


00:17:26.679 --> 00:17:28.990
from before these are stars where the


00:17:29.000 --> 00:17:32.070
light has taken decades to reach us and


00:17:32.080 --> 00:17:34.350
we are able to measure their velocity so


00:17:34.360 --> 00:17:36.230
accurately that we can see changes in


00:17:36.240 --> 00:17:40.110
that velocity of 50 cm a second wow


00:17:40.120 --> 00:17:41.870
that's just astonishing


00:17:41.880 --> 00:17:43.710
precision and that's what the team have


00:17:43.720 --> 00:17:47.230
done so they've observed this uh HD


00:17:47.240 --> 00:17:50.110
20794 for a number of years with haps


00:17:50.120 --> 00:17:52.390
getting more and more Data Tracking how


00:17:52.400 --> 00:17:54.350
the speed changes and in the past they'd


00:17:54.360 --> 00:17:56.710
found two planets in hints of a third


00:17:56.720 --> 00:17:59.149
and they've now confirmed that third one


00:17:59.159 --> 00:18:03.149
that third planet HD 20794 D is making


00:18:03.159 --> 00:18:05.870
the sty wobble with its speed changing


00:18:05.880 --> 00:18:09.310
by just 50 cm a second plus or minus


00:18:09.320 --> 00:18:12.029
over a period of about 700 days so


00:18:12.039 --> 00:18:14.830
you're watching for 700 days you get rid


00:18:14.840 --> 00:18:16.590
of all the other noise the star wobbling


00:18:16.600 --> 00:18:19.710
around itself just ulating like a shook


00:18:19.720 --> 00:18:21.750
Bell you get rid of the orbits of the


00:18:21.760 --> 00:18:23.230
two inner planets which are causing it


00:18:23.240 --> 00:18:24.750
to wobble by a similar amount with a


00:18:24.760 --> 00:18:26.990
different period on your left with a


00:18:27.000 --> 00:18:29.710
tiny wobble of plus orus 50 CM a second


00:18:29.720 --> 00:18:32.870
that takes 700 be to complete once and


00:18:32.880 --> 00:18:34.470
that's what they found so this is our


00:18:34.480 --> 00:18:37.190
planet it's a planet about 6 times the


00:18:37.200 --> 00:18:39.990
mass of the Earth at least might be more


00:18:40.000 --> 00:18:41.710
than that so we don't know how Edge on


00:18:41.720 --> 00:18:43.270
or Tilted the orbit is because we're not


00:18:43.280 --> 00:18:47.029
seeing it Transit if it's tilted by 30°


00:18:47.039 --> 00:18:48.669
the mass of this planet will be higher


00:18:48.679 --> 00:18:50.990
if it's tilted by 60° instead of being


00:18:51.000 --> 00:18:52.750
six Earth masses it'll be 12 Earth


00:18:52.760 --> 00:18:55.190
masses so this is the minimum


00:18:55.200 --> 00:18:58.270
Mass so it's what we call a super Earth


00:18:58.280 --> 00:19:01.350
or a inun it's much more massive than


00:19:01.360 --> 00:19:03.549
our planet and certainly larger than our


00:19:03.559 --> 00:19:07.110
planet it's moving on an orbit that if


00:19:07.120 --> 00:19:10.630
you calculated its semi- major axis the


00:19:10.640 --> 00:19:12.630
length of the ellipse half the length of


00:19:12.640 --> 00:19:14.789
the ellipse which sets a period that


00:19:14.799 --> 00:19:17.750
will put it in the habitable zone that's


00:19:17.760 --> 00:19:19.149
what the paper says now the habitable


00:19:19.159 --> 00:19:21.630
zone I'll get into in a second but this


00:19:21.640 --> 00:19:24.190
planet moves on a very elongated orbit


00:19:24.200 --> 00:19:26.149
so its distance from its Stars changing


00:19:26.159 --> 00:19:28.029
by a factor of two from its closest to


00:19:28.039 --> 00:19:30.590
the star to the furthest away now if you


00:19:30.600 --> 00:19:32.310
scale that up to the solar system and


00:19:32.320 --> 00:19:33.510
put it in the same place


00:19:33.520 --> 00:19:35.630
temperature-wise as it is in its system


00:19:35.640 --> 00:19:37.909
now if you put it in the solar system so


00:19:37.919 --> 00:19:39.950
that its orbit had that same temperature


00:19:39.960 --> 00:19:41.950
range that would mean when it's closest


00:19:41.960 --> 00:19:44.230
to its star it's as close as Venus when


00:19:44.240 --> 00:19:45.870
it's furthest from its star it's further


00:19:45.880 --> 00:19:49.190
out than mes you're going to have


00:19:49.200 --> 00:19:51.590
extreme extreme temperature variability


00:19:51.600 --> 00:19:55.149
on this planet now the habitable zone is


00:19:55.159 --> 00:19:56.990
always thrown out for these planets it's


00:19:57.000 --> 00:19:58.750
that goldilox IDE here if you have a


00:19:58.760 --> 00:20:00.470
Planet that's at the right distance from


00:20:00.480 --> 00:20:02.789
the Star the temperature will be not too


00:20:02.799 --> 00:20:04.390
hot and not too cold and it'll be just


00:20:04.400 --> 00:20:06.149
right for liquid water on the


00:20:06.159 --> 00:20:09.350
surface the Supple implication buried in


00:20:09.360 --> 00:20:12.029
this is not actually what I just said


00:20:12.039 --> 00:20:14.830
but it's rather if you took the Earth as


00:20:14.840 --> 00:20:17.750
the Earth is today and dropped it where


00:20:17.760 --> 00:20:19.590
this planet is would the Earth still


00:20:19.600 --> 00:20:22.270
have liquid water on its surface now


00:20:22.280 --> 00:20:24.270
that's a subtle difference but to


00:20:24.280 --> 00:20:25.470
illustrate it if you think about the


00:20:25.480 --> 00:20:28.230
solar system the boundaries of the


00:20:28.240 --> 00:20:30.070
habitable are usually set by looking at


00:20:30.080 --> 00:20:32.270
Venus and Mars that's what's motivated


00:20:32.280 --> 00:20:34.350
this the calculations are more robust


00:20:34.360 --> 00:20:36.710
now but that's about where it washes out


00:20:36.720 --> 00:20:38.950
Venus closer to the Sun than o is super


00:20:38.960 --> 00:20:41.669
hot 450° Centigrade on the surface and


00:20:41.679 --> 00:20:44.430
clearly not habitable Mars is super cold


00:20:44.440 --> 00:20:46.310
it's too cold for life it's outside the


00:20:46.320 --> 00:20:47.669
habitable zone the Earth's in the middle


00:20:47.679 --> 00:20:50.390
and it's just right but to illustrate


00:20:50.400 --> 00:20:52.350
why it's not so simple imagine a thought


00:20:52.360 --> 00:20:54.270
experiment where you swap Venus and Mars


00:20:54.280 --> 00:20:56.750
around if you put Mars where Venus is


00:20:56.760 --> 00:20:59.350
it's got a thinner atmosphere than we do


00:20:59.360 --> 00:21:01.149
so it's got less of a greenhouse effect


00:21:01.159 --> 00:21:03.669
so it would probably remain Clement


00:21:03.679 --> 00:21:06.029
where Venus would overheat similarly if


00:21:06.039 --> 00:21:07.990
you put Venus where Mars is Venus has


00:21:08.000 --> 00:21:10.029
this incredibly thick atmosphere with an


00:21:10.039 --> 00:21:12.390
incredibly strong Greenhouse it will


00:21:12.400 --> 00:21:14.310
probably still be habitable it would


00:21:14.320 --> 00:21:16.669
still be warm enough where Mars wouldn't


00:21:16.679 --> 00:21:18.990
so this habitable zone is a much wooler


00:21:19.000 --> 00:21:22.630
concept than I think most people realize


00:21:22.640 --> 00:21:25.230
and it's just not really a guideline


00:21:25.240 --> 00:21:27.269
it's just an indication that this could


00:21:27.279 --> 00:21:28.870
be somewhere worth looking at it's not


00:21:28.880 --> 00:21:30.110
more than that but it tends to get


00:21:30.120 --> 00:21:32.990
played up as being the Holy Grail a


00:21:33.000 --> 00:21:35.269
planet is in the habitable zone it must


00:21:35.279 --> 00:21:36.750
therefore have the potential to be


00:21:36.760 --> 00:21:38.630
habitable whereas in fact what you're


00:21:38.640 --> 00:21:40.470
saying is if you put the Earth on the


00:21:40.480 --> 00:21:42.310
orbit that this planet is on it might


00:21:42.320 --> 00:21:44.590
still look like the earth except with


00:21:44.600 --> 00:21:45.750
the planet we're talking about at the


00:21:45.760 --> 00:21:47.830
minute if you put the Earth on that


00:21:47.840 --> 00:21:50.470
orbit at per helium when it was closest


00:21:50.480 --> 00:21:53.029
to the Sun it would receive a flots from


00:21:53.039 --> 00:21:54.750
the Sun as high as Venus does so the


00:21:54.760 --> 00:21:57.190
oceans would start to boil fortunately


00:21:57.200 --> 00:21:59.190
it doesn't spend long at peral


00:21:59.200 --> 00:22:00.710
we move quickest when we're closest to


00:22:00.720 --> 00:22:02.669
the object we swing out through the


00:22:02.679 --> 00:22:05.029
habitable zone probably everything's


00:22:05.039 --> 00:22:06.710
fine but you've got Bonkers weather


00:22:06.720 --> 00:22:07.669
because you're dealing with all that


00:22:07.679 --> 00:22:09.789
heat you've just been given then you get


00:22:09.799 --> 00:22:11.870
to your furthest point from the Star and


00:22:11.880 --> 00:22:13.950
that's when you move the slowest so this


00:22:13.960 --> 00:22:15.990
planet spends probably more than 50% of


00:22:16.000 --> 00:22:18.590
its time further from its star than the


00:22:18.600 --> 00:22:20.269
outer edge of that habitable zone by


00:22:20.279 --> 00:22:22.950
calculation so those oceans will freeze


00:22:22.960 --> 00:22:24.909
and you get this deep game of thron


00:22:24.919 --> 00:22:26.470
style winter you'd have everybody going


00:22:26.480 --> 00:22:28.789
oh look winter is coming everybody


00:22:28.799 --> 00:22:30.830
doomed and then it would swing back into


00:22:30.840 --> 00:22:32.669
the star and have a brief furnace like


00:22:32.679 --> 00:22:35.310
summer and then a long cold winter again


00:22:35.320 --> 00:22:37.470
it doesn't sound particularly Clement


00:22:37.480 --> 00:22:38.750
you add to that though the fact that


00:22:38.760 --> 00:22:40.590
this planet is six times the mass of the


00:22:40.600 --> 00:22:42.990
Earth means it's going to have a very


00:22:43.000 --> 00:22:44.510
substantial atmosphere and I should say


00:22:44.520 --> 00:22:46.830
at least six times the MTH of the earth


00:22:46.840 --> 00:22:48.590
a much thicker atmosphere means a much


00:22:48.600 --> 00:22:51.110
stronger greenhouse effect which means


00:22:51.120 --> 00:22:53.549
the results of that extreme insulation


00:22:53.559 --> 00:22:56.070
the extreme radiation at pericenter when


00:22:56.080 --> 00:22:58.510
it's closest to the star is even more


00:22:58.520 --> 00:23:00.710
pronounced so I don't think it's at all


00:23:00.720 --> 00:23:02.350
fair to say that this planet could be


00:23:02.360 --> 00:23:04.470
potentially habitable and in fact the


00:23:04.480 --> 00:23:06.269
authors of the paper themselves don't


00:23:06.279 --> 00:23:08.669
really say that what they do say is that


00:23:08.679 --> 00:23:10.909
this planet crosses the habitable zone


00:23:10.919 --> 00:23:12.269
and because it's a bit bigger and


00:23:12.279 --> 00:23:14.149
because it has this big variation it


00:23:14.159 --> 00:23:16.269
assistance from the Star and because


00:23:16.279 --> 00:23:18.430
it's around a nearby star could be a


00:23:18.440 --> 00:23:20.870
really good test case for us to practice


00:23:20.880 --> 00:23:22.870
our observation techniques to learn more


00:23:22.880 --> 00:23:25.350
about atmospheres of planets this size


00:23:25.360 --> 00:23:27.070
before we really look at ones that could


00:23:27.080 --> 00:23:29.269
be habitable and Earth like


00:23:29.279 --> 00:23:31.789
but this planet certainly isn't it and


00:23:31.799 --> 00:23:33.310
even then there's a whole heap of other


00:23:33.320 --> 00:23:34.909
things that will impact habitability


00:23:34.919 --> 00:23:36.669
which we may or may not have time to go


00:23:36.679 --> 00:23:39.110
into today but the habitable zone really


00:23:39.120 --> 00:23:42.149
is just the first of an incredibly long


00:23:42.159 --> 00:23:44.110
list of variables that you can slide


00:23:44.120 --> 00:23:45.990
around that could influence their


00:23:46.000 --> 00:23:48.070
habitability so all it's saying is how


00:23:48.080 --> 00:23:49.430
hot would the Earth be if you put it


00:23:49.440 --> 00:23:52.070
there essentially yeah yeah and at six


00:23:52.080 --> 00:23:54.470
times the size of the Earth at least


00:23:54.480 --> 00:23:56.350
gravity has to be a factor as well


00:23:56.360 --> 00:23:59.269
doesn't it it does I mean if you


00:23:59.279 --> 00:24:01.110
estimated that this thing is twice the


00:24:01.120 --> 00:24:02.830
Earth diameter and we don't know that


00:24:02.840 --> 00:24:05.269
because this thing doesn't Transit its


00:24:05.279 --> 00:24:07.269
star or we've never seen it transited


00:24:07.279 --> 00:24:09.190
that so it orbit is almost certainly not


00:24:09.200 --> 00:24:11.029
Edge on which means its mass is probably


00:24:11.039 --> 00:24:13.390
a bit higher than we say that minimum is


00:24:13.400 --> 00:24:15.269
but it means we have no way of measuring


00:24:15.279 --> 00:24:18.190
the size now at six Earth masses are a


00:24:18.200 --> 00:24:19.630
bit heavier it's near this boundary


00:24:19.640 --> 00:24:22.590
between what we call superar or and inet


00:24:22.600 --> 00:24:24.669
super Earth is a rocky object with a big


00:24:24.679 --> 00:24:27.230
thick atmosphere A Min Neptune is a big


00:24:27.240 --> 00:24:29.149
thick atmosphere with a rocky car so you


00:24:29.159 --> 00:24:30.830
can see how that transitions between


00:24:30.840 --> 00:24:32.909
them but if you estimate for a minute


00:24:32.919 --> 00:24:34.549
that it is a super Earth with a bit of a


00:24:34.559 --> 00:24:36.510
thick atmosphere you could say well


00:24:36.520 --> 00:24:38.110
maybe it's twice the diameter of the


00:24:38.120 --> 00:24:41.110
earth and that would kind of make sense


00:24:41.120 --> 00:24:42.750
density wise that would place it a


00:24:42.760 --> 00:24:44.870
little bit less dense of the Earth but


00:24:44.880 --> 00:24:46.710
that might make sense it's a little bit


00:24:46.720 --> 00:24:49.830
cooler for a lot of its orbit even in


00:24:49.840 --> 00:24:52.029
that scenario the acceleration due to


00:24:52.039 --> 00:24:54.110
gravity on its surface will be 50%


00:24:54.120 --> 00:24:55.669
higher than that we have on the Earth


00:24:55.679 --> 00:24:58.070
right now you know so gravity will be


00:24:58.080 --> 00:24:59.950
strong we'd probably all if we were


00:24:59.960 --> 00:25:02.430
there be Squat and dumpy and grumbling


00:25:02.440 --> 00:25:04.230
about how heavy we feel and all the rest


00:25:04.240 --> 00:25:05.950
of it you know I'm heavy enough already


00:25:05.960 --> 00:25:07.510
without giving me


00:25:07.520 --> 00:25:11.830
50 yes no that's a fair point but uh


00:25:11.840 --> 00:25:13.350
yeah these these stories are not


00:25:13.360 --> 00:25:15.590
uncommon now and you make a a very valid


00:25:15.600 --> 00:25:17.269
point that people will just you know


00:25:17.279 --> 00:25:19.430
when the day comes that we've genuinely


00:25:19.440 --> 00:25:21.549
got an earth like planet Earth


00:25:21.559 --> 00:25:24.590
2.0 uh that could Harbor life people to


00:25:24.600 --> 00:25:28.710
go yeah Roo yeah heard it all before and


00:25:28.720 --> 00:25:31.110
it it's dangerous and quite often the


00:25:31.120 --> 00:25:33.070
researchers involved don't have control


00:25:33.080 --> 00:25:35.230
of that story that's one of the reasons


00:25:35.240 --> 00:25:37.430
I love working with websites like the


00:25:37.440 --> 00:25:38.830
conversation where I control the


00:25:38.840 --> 00:25:40.710
narrative when I write articles but it's


00:25:40.720 --> 00:25:42.870
also why I really appreciate our media


00:25:42.880 --> 00:25:45.590
team here at unq because they actually


00:25:45.600 --> 00:25:47.070
talked with them when they're writing


00:25:47.080 --> 00:25:49.269
media releases and a lot of the bigger


00:25:49.279 --> 00:25:51.350
universities the media team get a hold


00:25:51.360 --> 00:25:52.710
of the paper and they write their own


00:25:52.720 --> 00:25:54.430
interpretation of it with a couple of


00:25:54.440 --> 00:25:55.830
quotes from the authors but they don't


00:25:55.840 --> 00:25:58.430
let the authors read the release then


00:25:58.440 --> 00:25:59.830
you get journalists who read the media


00:25:59.840 --> 00:26:01.950
releasee and spin it further yeah and


00:26:01.960 --> 00:26:03.590
you end up from an article that says we


00:26:03.600 --> 00:26:05.190
found a planet that is interesting to


00:26:05.200 --> 00:26:07.590
being new Earth planet has been found


00:26:07.600 --> 00:26:10.669
life 2. not is there and that's not what


00:26:10.679 --> 00:26:13.350
anybody actually said no but it's a good


00:26:13.360 --> 00:26:14.750
way to get hits and links to your


00:26:14.760 --> 00:26:18.310
University's website exactly yeah okay


00:26:18.320 --> 00:26:20.350
uh if you'd like to read up on that uh


00:26:20.360 --> 00:26:22.389
the genuine article I'm talking about uh


00:26:22.399 --> 00:26:24.789
you can find it in the journal astronomy


00:26:24.799 --> 00:26:25.710
and


00:26:25.720 --> 00:26:27.870
astrophysics if you feel better now that


00:26:27.880 --> 00:26:30.149
you've got that off your chest joh oh


00:26:30.159 --> 00:26:32.110
this is a Perpetual rant of man I


00:26:32.120 --> 00:26:34.750
actually did with my former Mentor Barry


00:26:34.760 --> 00:26:36.830
Jones who passed away about a decade ago


00:26:36.840 --> 00:26:39.710
now um we wrote my first ever review


00:26:39.720 --> 00:26:41.830
paper back in 2010 where I dag it dug


00:26:41.840 --> 00:26:44.029
into this so it always used to bug me


00:26:44.039 --> 00:26:45.990
that it was just is in the habitable


00:26:46.000 --> 00:26:48.350
zone right that's job done and so we


00:26:48.360 --> 00:26:49.990
wrote this paper where we looked at all


00:26:50.000 --> 00:26:51.590
of the other things people have proposed


00:26:51.600 --> 00:26:53.230
that could make a planet more habitable


00:26:53.240 --> 00:26:55.669
or less habitable more suitable and for


00:26:55.679 --> 00:26:58.630
me the thing here is when we get get to


00:26:58.640 --> 00:27:00.669
do observations to look for life on


00:27:00.679 --> 00:27:02.350
these planets which is still a bit


00:27:02.360 --> 00:27:04.149
beyond us but we're getting towards that


00:27:04.159 --> 00:27:06.630
point those observations are going to be


00:27:06.640 --> 00:27:08.510
the hardest observations Humanity's ever


00:27:08.520 --> 00:27:10.590
had to carry out you're talking hundreds


00:27:10.600 --> 00:27:12.269
or thousands of hours on the biggest


00:27:12.279 --> 00:27:15.710
space telescopes really competitive time


00:27:15.720 --> 00:27:16.830
you're not going to be able to look at


00:27:16.840 --> 00:27:18.149
them all so you're going to have to find


00:27:18.159 --> 00:27:20.149
a way to pick the best Target you're


00:27:20.159 --> 00:27:21.350
going to have to find a way to whittle


00:27:21.360 --> 00:27:22.870
down a list of hundreds or thousands


00:27:22.880 --> 00:27:25.230
into the best two or three and you can't


00:27:25.240 --> 00:27:26.870
just use the habitables on that so I


00:27:26.880 --> 00:27:28.549
thought let's look at all the things


00:27:28.559 --> 00:27:30.909
that can impact habitability to see if


00:27:30.919 --> 00:27:32.549
you can turn them almost into the volume


00:27:32.559 --> 00:27:35.430
sliders on the mixing desk of the DJ


00:27:35.440 --> 00:27:36.710
right you can turn them up turn them


00:27:36.720 --> 00:27:39.510
down and see which planet gets the best


00:27:39.520 --> 00:27:41.230
score overall when you factor all of


00:27:41.240 --> 00:27:43.149
them in and some of them are things we


00:27:43.159 --> 00:27:44.590
can't yet observe some of them are


00:27:44.600 --> 00:27:46.269
things you might have to model with


00:27:46.279 --> 00:27:48.950
computer modeling like I do but it can


00:27:48.960 --> 00:27:50.350
be everything from the nature of the


00:27:50.360 --> 00:27:53.110
star itself how variable it is all the


00:27:53.120 --> 00:27:54.750
way through to the other planets in the


00:27:54.760 --> 00:27:56.470
system what their gravity does how much


00:27:56.480 --> 00:27:58.750
debris there is and even down to the


00:27:58.760 --> 00:28:00.269
planet itself whether it has PL


00:28:00.279 --> 00:28:02.110
tectonics whether it has magnetic field


00:28:02.120 --> 00:28:04.389
all of these things will factor in it's


00:28:04.399 --> 00:28:06.389
not just as simple as where do you play


00:28:06.399 --> 00:28:09.830
it is it in the right spot no valid


00:28:09.840 --> 00:28:12.669
point all right uh yeah as I said you


00:28:12.679 --> 00:28:14.310
can uh chase that story up about


00:28:14.320 --> 00:28:16.630
astronomy and astrophysics uh you could


00:28:16.640 --> 00:28:18.190
probably find it just about anywhere


00:28:18.200 --> 00:28:20.310
online uh there's an article on


00:28:20.320 --> 00:28:23.190
space.com as well this is Space Nuts


00:28:23.200 --> 00:28:29.070
with Andrew Dunley and joty Horner


00:28:29.080 --> 00:28:31.870
and I feel fine Space Nuts right our


00:28:31.880 --> 00:28:36.070
next story uh which we've uh done before


00:28:36.080 --> 00:28:39.190
we did it a week ago uh about uh the


00:28:39.200 --> 00:28:42.909
comet 2024 yr4 I happen to be playing


00:28:42.919 --> 00:28:46.190
our podcast in the car I always like to


00:28:46.200 --> 00:28:48.310
listen to it just to see how it sounds


00:28:48.320 --> 00:28:50.509
and you know decide whether or not I'm


00:28:50.519 --> 00:28:53.350
doing a good job or not did it in radio


00:28:53.360 --> 00:28:55.630
do it with the podcast but I I was


00:28:55.640 --> 00:28:57.830
picking up our grandchildren from school


00:28:57.840 --> 00:29:03.230
and and uh Nathaniel who um is 10 years


00:29:03.240 --> 00:29:05.990
old um he was listening and he said to


00:29:06.000 --> 00:29:09.870
me is it comat going to hit Earth and I


00:29:09.880 --> 00:29:12.110
had to kind of explain to him what was


00:29:12.120 --> 00:29:14.310
going on without alarming


00:29:14.320 --> 00:29:17.389
him uh and now an update on the story


00:29:17.399 --> 00:29:20.789
last week we were saying um there was a


00:29:20.799 --> 00:29:24.549
70 to 77% chance of this thing um


00:29:24.559 --> 00:29:26.789
hitting the atmosphere in


00:29:26.799 --> 00:29:29.590
20327 so


00:29:29.600 --> 00:29:32.350
sorry yeah see that's that was a popular


00:29:32.360 --> 00:29:35.070
press comment one in S7 but now that


00:29:35.080 --> 00:29:38.470
number's dropped as at now but that


00:29:38.480 --> 00:29:41.269
could change again absolutely so as of


00:29:41.279 --> 00:29:43.070
today so when I sent you notes through


00:29:43.080 --> 00:29:46.190
yesterday it was at 1 in 43 he now


00:29:46.200 --> 00:29:48.389
falling back to 1 in 48 this number is


00:29:48.399 --> 00:29:51.070
changing every day and what we will see


00:29:51.080 --> 00:29:52.830
and what we'll continue to see is most


00:29:52.840 --> 00:29:56.789
likely those odds of an impact gradually


00:29:56.799 --> 00:29:59.269
increasing and until eventually they


00:29:59.279 --> 00:30:02.269
most likely drop to zero and the reason


00:30:02.279 --> 00:30:03.269
for that is we're getting more


00:30:03.279 --> 00:30:05.389
observations with every day that passes


00:30:05.399 --> 00:30:06.990
and so with every day that passes we get


00:30:07.000 --> 00:30:10.029
a refined estimate of the orbit of this


00:30:10.039 --> 00:30:13.070
thing that then means that the exact


00:30:13.080 --> 00:30:15.149
location of the object on 22nd of


00:30:15.159 --> 00:30:18.750
December 2032 has a smaller uncertainty


00:30:18.760 --> 00:30:21.149
so that big area of space that we think


00:30:21.159 --> 00:30:22.950
it will be in with each day's


00:30:22.960 --> 00:30:25.669
observations get smaller and smaller now


00:30:25.679 --> 00:30:27.590
if the Earth is still in that area of


00:30:27.600 --> 00:30:28.590
space


00:30:28.600 --> 00:30:30.350
the Earth is a bigger fraction of that


00:30:30.360 --> 00:30:32.669
total volume of space and so the


00:30:32.679 --> 00:30:34.710
probability of impact is going up


00:30:34.720 --> 00:30:36.029
because we're a bigger fraction of the


00:30:36.039 --> 00:30:38.149
total area that thing could be in but at


00:30:38.159 --> 00:30:40.070
some point as that volume of space


00:30:40.080 --> 00:30:42.350
shrinks down the Earth could fall out of


00:30:42.360 --> 00:30:44.029
it and at that point the probability


00:30:44.039 --> 00:30:46.549
immediately drops to zero so it isn't a


00:30:46.559 --> 00:30:48.789
reason to panic at all this is exactly


00:30:48.799 --> 00:30:51.750
the behavior you would expect to see but


00:30:51.760 --> 00:30:53.630
that probability will continue to change


00:30:53.640 --> 00:30:55.470
day by day wouldn't surprise me if it


00:30:55.480 --> 00:30:58.470
keeps getting higher now this asid we're


00:30:58.480 --> 00:31:00.389
probably going to lose Tru of in about


00:31:00.399 --> 00:31:02.310
April a little bit too far away to


00:31:02.320 --> 00:31:04.750
observe then we won't see it again till


00:31:04.760 --> 00:31:07.029
2028 people are digging back through


00:31:07.039 --> 00:31:11.350
archival observations from 2016 2012


00:31:11.360 --> 00:31:13.549
2008 because this thing comes roughly


00:31:13.559 --> 00:31:16.029
near the Earth every four years or so if


00:31:16.039 --> 00:31:18.909
we find it by chance on one photograph


00:31:18.919 --> 00:31:21.230
from one of those previous years this


00:31:21.240 --> 00:31:22.909
probability will change dramatically and


00:31:22.919 --> 00:31:24.389
will'll probably drop to zero straight


00:31:24.399 --> 00:31:27.310
away if not we'll have to wait till 2028


00:31:27.320 --> 00:31:28.950
and until then then we'll see this


00:31:28.960 --> 00:31:31.350
continual slight wobbling around as each


00:31:31.360 --> 00:31:33.230
day's observations coming and it gets


00:31:33.240 --> 00:31:36.230
recalculated so fundamentally nothing


00:31:36.240 --> 00:31:38.110
has changed this things still pose as a


00:31:38.120 --> 00:31:40.029
threat do not panic even if it were to


00:31:40.039 --> 00:31:41.430
hit us it's not really going to cause a


00:31:41.440 --> 00:31:43.750
problem anyway to be brutally honest but


00:31:43.760 --> 00:31:46.389
it is fascinating to watch this happen


00:31:46.399 --> 00:31:48.990
and to see that evolution in real


00:31:49.000 --> 00:31:51.430
time absolutely yeah I think I said


00:31:51.440 --> 00:31:54.710
Comet I meant asteroid but um yeah 2024


00:31:54.720 --> 00:31:58.149
y4 if you do a search on Google whatever


00:31:58.159 --> 00:31:59.590
your favorite search engine is you'll


00:31:59.600 --> 00:32:01.029
find plenty of


00:32:01.039 --> 00:32:04.190
information and you I I would advise


00:32:04.200 --> 00:32:06.549
filtering the popular press comments


00:32:06.559 --> 00:32:09.029
because that they uh they've been going


00:32:09.039 --> 00:32:11.350
hammer and tongs on this one absolutely


00:32:11.360 --> 00:32:14.470
um but yeah it like like Johny said on


00:32:14.480 --> 00:32:16.909
the previous story uh it's clickbait


00:32:16.919 --> 00:32:18.830
isn't it um that's something that's


00:32:18.840 --> 00:32:21.549
really it but I I did reassure my


00:32:21.559 --> 00:32:23.430
grandson because as soon as I finished


00:32:23.440 --> 00:32:25.590
explaining it he wanted to talk about


00:32:25.600 --> 00:32:28.190
Pokemon so I think I was sucess in


00:32:28.200 --> 00:32:31.269
deflecting him there uh to our final


00:32:31.279 --> 00:32:34.149
story jonty and this one is about stuff


00:32:34.159 --> 00:32:36.470
that's hitting the atmosphere we're


00:32:36.480 --> 00:32:39.669
talking specifically about the um


00:32:39.679 --> 00:32:43.430
turnover of SpaceX satellites uh they've


00:32:43.440 --> 00:32:47.230
been starting to rain down on Earth uh


00:32:47.240 --> 00:32:49.029
fairly regularly in fact uh the Space


00:32:49.039 --> 00:32:52.430
Nuts podcast group on Facebook uh has


00:32:52.440 --> 00:32:55.149
been um discussing this they they put an


00:32:55.159 --> 00:32:57.990
article on there that the the listeners


00:32:58.000 --> 00:33:01.389
were discussing and some some were quite


00:33:01.399 --> 00:33:03.389
surprised by the kinds of numbers we're


00:33:03.399 --> 00:33:05.310
talking about but this is just going to


00:33:05.320 --> 00:33:07.950
get more and more significant as time


00:33:07.960 --> 00:33:09.430
goes on because they haven't finished


00:33:09.440 --> 00:33:10.710
deploying their


00:33:10.720 --> 00:33:13.110
entire uh Fleet or whatever you want to


00:33:13.120 --> 00:33:16.870
call them of SpaceX satellites yeah this


00:33:16.880 --> 00:33:19.350
is yet another multifaceted story so I


00:33:19.360 --> 00:33:21.789
know a lot of people who get very


00:33:21.799 --> 00:33:23.350
passionate in their defense of SpaceX


00:33:23.360 --> 00:33:25.230
and the AL musk and many others who have


00:33:25.240 --> 00:33:26.710
very negative views of them and I was


00:33:26.720 --> 00:33:28.909
try and be somewhere in the middle big


00:33:28.919 --> 00:33:30.990
sack it's like in literature if you ever


00:33:31.000 --> 00:33:34.070
read a book very few people are purely


00:33:34.080 --> 00:33:35.470
evil or purely good everybody's


00:33:35.480 --> 00:33:37.269
somewhere in the middle unless it's a


00:33:37.279 --> 00:33:40.070
bad book and it's the same with things


00:33:40.080 --> 00:33:41.470
like this there's a lot of good about


00:33:41.480 --> 00:33:43.789
this and a lot of bad about it now Spex


00:33:43.799 --> 00:33:46.549
are putting up their St satellites to


00:33:46.559 --> 00:33:49.909
deliver internet access which is a great


00:33:49.919 --> 00:33:51.269
benefit to people in the regions you


00:33:51.279 --> 00:33:53.669
know and I've heard plenty of stories of


00:33:53.679 --> 00:33:55.190
people who are living remotely in


00:33:55.200 --> 00:33:56.789
Australia who can't get a good internet


00:33:56.799 --> 00:33:58.110
connection and styling has been


00:33:58.120 --> 00:34:00.590
revolutionary to them yeah and and


00:34:00.600 --> 00:34:03.830
cruise ships use styling AB because


00:34:03.840 --> 00:34:05.750
they're always they're in remote areas a


00:34:05.760 --> 00:34:08.829
lot yeah it is a really incredible


00:34:08.839 --> 00:34:10.310
technological development on the other


00:34:10.320 --> 00:34:11.710
hand you've got all the concerns about


00:34:11.720 --> 00:34:13.629
the light pollution from these


00:34:13.639 --> 00:34:16.030
things and the fact that they launch


00:34:16.040 --> 00:34:17.669
them without anybody really being able


00:34:17.679 --> 00:34:21.669
to regulate it or say boot about it it


00:34:21.679 --> 00:34:23.790
it's a multifaceted problem and there's


00:34:23.800 --> 00:34:26.230
good things and bad things about it in


00:34:26.240 --> 00:34:28.790
much the same way this story is both a


00:34:28.800 --> 00:34:30.710
good and bad story you've got all these


00:34:30.720 --> 00:34:33.669
satellites up there and they have finite


00:34:33.679 --> 00:34:36.710
lifetimes they are low down because you


00:34:36.720 --> 00:34:38.470
need them to be in low earth orbit in


00:34:38.480 --> 00:34:39.990
order to get good latency if you put


00:34:40.000 --> 00:34:42.149
these at G stationary orbit you've got


00:34:42.159 --> 00:34:43.790
the light travel time there and Back


00:34:43.800 --> 00:34:46.270
Again you've got a long way to go and


00:34:46.280 --> 00:34:48.270
that puts a significant ping which means


00:34:48.280 --> 00:34:50.389
for the people playing twitch games and


00:34:50.399 --> 00:34:52.790
firstperson shooter games they complain


00:34:52.800 --> 00:34:55.750
and Suk um but everybody wants a faster


00:34:55.760 --> 00:34:57.030
internet connection with the lowest


00:34:57.040 --> 00:34:58.710
latency possible so these things are in


00:34:58.720 --> 00:35:00.910
low earth orbit which means that they


00:35:00.920 --> 00:35:03.230
are moving through a significant chunk


00:35:03.240 --> 00:35:04.510
of the Earth's atmosphere the Earth's


00:35:04.520 --> 00:35:05.990
atmosphere doesn't just stop it just


00:35:06.000 --> 00:35:07.390
gets thinner and thinner and thinner the


00:35:07.400 --> 00:35:09.390
further you go away technically the


00:35:09.400 --> 00:35:10.790
Moon's still encountering bits of the


00:35:10.800 --> 00:35:12.069
Earth's atmosphere it should by that


00:35:12.079 --> 00:35:13.750
point it's still thinnest to be


00:35:13.760 --> 00:35:15.430
irrelevant but at the altitude of these


00:35:15.440 --> 00:35:17.870
siling satellites they are actually


00:35:17.880 --> 00:35:20.870
traveling into a headwind so without


00:35:20.880 --> 00:35:22.230
something to bump them up they would


00:35:22.240 --> 00:35:24.150
eventually come down naturally anyway


00:35:24.160 --> 00:35:27.829
but also they are a fixed term thing


00:35:27.839 --> 00:35:30.030
they typically I think thinking about an


00:35:30.040 --> 00:35:31.470
individual satellite having about a


00:35:31.480 --> 00:35:34.270
fiveyear lifetime yeah now it's about


00:35:34.280 --> 00:35:35.950
five years since the Starlet Sates


00:35:35.960 --> 00:35:37.470
started getting launched which means the


00:35:37.480 --> 00:35:40.109
very first generation of them are now in


00:35:40.119 --> 00:35:41.670
their retirement


00:35:41.680 --> 00:35:45.270
phase what is really good about this is


00:35:45.280 --> 00:35:48.630
that SpaceX and starlink are being very


00:35:48.640 --> 00:35:50.990
aggressive in the retirement in that


00:35:51.000 --> 00:35:52.589
they are controlling these things and


00:35:52.599 --> 00:35:54.069
deliberately putting them back in the


00:35:54.079 --> 00:35:55.710
atmosphere to burn up in a controlled


00:35:55.720 --> 00:35:57.750
fashion so they're controlling where


00:35:57.760 --> 00:35:59.109
they drop them into the atmosphere to


00:35:59.119 --> 00:36:01.990
minimize the risk to air travel and the


00:36:02.000 --> 00:36:03.630
risk of them dropping on a city and


00:36:03.640 --> 00:36:06.230
things like this and that is really good


00:36:06.240 --> 00:36:07.710
governance it's really important to say


00:36:07.720 --> 00:36:09.910
that there's a lot of stuff up there


00:36:09.920 --> 00:36:11.710
that will come down of its own accord at


00:36:11.720 --> 00:36:14.550
its own time with no control over it and


00:36:14.560 --> 00:36:16.630
that's a risk and people are talking


00:36:16.640 --> 00:36:17.990
about the fact that there's probably as


00:36:18.000 --> 00:36:20.790
high as a 26% chance that in a given


00:36:20.800 --> 00:36:23.349
year from now on Space Dey will fall


00:36:23.359 --> 00:36:25.510
through a populated


00:36:25.520 --> 00:36:27.870
airspace which is problematic there's


00:36:27.880 --> 00:36:29.670
even studies saying there's a one in 10


00:36:29.680 --> 00:36:31.589
chance that within the next decade


00:36:31.599 --> 00:36:33.430
somebody will die as a result of Spar


00:36:33.440 --> 00:36:36.870
Dey hitting them so that's a concern and


00:36:36.880 --> 00:36:38.950
by deliberately deorbiting these things


00:36:38.960 --> 00:36:40.230
in a controlled fashion they're


00:36:40.240 --> 00:36:42.030
mitigating those risks they're putting


00:36:42.040 --> 00:36:44.510
things down in a safe fashion but


00:36:44.520 --> 00:36:45.910
because of how many satellites they're


00:36:45.920 --> 00:36:47.710
putting up there that means we've got an


00:36:47.720 --> 00:36:49.390
increasing number of them coming back


00:36:49.400 --> 00:36:52.510
down there are currently 7,000 stying


00:36:52.520 --> 00:36:54.710
satellites up there the goal is to get


00:36:54.720 --> 00:36:58.270
up to 42,000 that is their sta there so


00:36:58.280 --> 00:37:01.950
that's of more yeah that's just Starling


00:37:01.960 --> 00:37:04.670
because there are many others there are


00:37:04.680 --> 00:37:06.589
if you look at all of the proposed Mega


00:37:06.599 --> 00:37:08.309
constellations I think the current


00:37:08.319 --> 00:37:10.030
number is that there could be as many as


00:37:10.040 --> 00:37:12.589
550,000 satellites in orbit within a


00:37:12.599 --> 00:37:14.790
decade which makes me as an amateur


00:37:14.800 --> 00:37:16.670
astronomer the kind of P me that does


00:37:16.680 --> 00:37:18.309
out and observes mete shs and stuff just


00:37:18.319 --> 00:37:20.430
makes me weak because we'll lose the


00:37:20.440 --> 00:37:22.790
night sky to such a degree but that


00:37:22.800 --> 00:37:25.069
that's a slightly separate thing with


00:37:25.079 --> 00:37:26.950
7,000 up there at the minute the


00:37:26.960 --> 00:37:28.670
retirements of those first gen ones are


00:37:28.680 --> 00:37:30.190
now coming at a rate of four or five


00:37:30.200 --> 00:37:33.109
satellites per day so that means four or


00:37:33.119 --> 00:37:34.829
five satellites are burning up somewhere


00:37:34.839 --> 00:37:37.990
over the Earth every single day of the


00:37:38.000 --> 00:37:39.069
calendar


00:37:39.079 --> 00:37:41.190
year that's only going to go up because


00:37:41.200 --> 00:37:42.589
if you increase the number of satellites


00:37:42.599 --> 00:37:45.109
up there by a factor of six times then


00:37:45.119 --> 00:37:46.150
you'll increase that number of


00:37:46.160 --> 00:37:48.270
re-entries per day by factor of six


00:37:48.280 --> 00:37:50.710
times so within five years we could well


00:37:50.720 --> 00:37:53.870
be looking at something nearer to 25 or


00:37:53.880 --> 00:37:55.670
even 30 satellites per day coming back


00:37:55.680 --> 00:37:57.910
into the atmosphere now the are coming


00:37:57.920 --> 00:38:00.030
in in a controlled fashion so they're


00:38:00.040 --> 00:38:01.990
trying to drop them in the atmosphere


00:38:02.000 --> 00:38:03.349
away from things that would be


00:38:03.359 --> 00:38:05.510
threatened by lumps of metal hitting the


00:38:05.520 --> 00:38:08.109
ice atmosphere essentially yeah but


00:38:08.119 --> 00:38:09.829
there is now a growing concern about the


00:38:09.839 --> 00:38:12.990
pollution side of this that's the I was


00:38:13.000 --> 00:38:15.309
getting yeah that's the that's the big


00:38:15.319 --> 00:38:17.390
if isn't it and it's a difficult one


00:38:17.400 --> 00:38:18.750
because it's not an experiment that's


00:38:18.760 --> 00:38:20.710
ever been done before things have


00:38:20.720 --> 00:38:22.870
re-entered um but in the past we've not


00:38:22.880 --> 00:38:24.510
been putting much up in space so it's


00:38:24.520 --> 00:38:26.829
been a very rare thing a little bit of


00:38:26.839 --> 00:38:28.230
extra material dumped into the


00:38:28.240 --> 00:38:30.750
atmosphere a tiny amount compared to the


00:38:30.760 --> 00:38:32.069
amount that comes in natural through


00:38:32.079 --> 00:38:33.550
metas and


00:38:33.560 --> 00:38:35.790
meteorites um stuff hitting the S


00:38:35.800 --> 00:38:36.950
atmosphere naturally but we're now


00:38:36.960 --> 00:38:38.430
getting to a stage where this is a


00:38:38.440 --> 00:38:40.990
significant amount of material entering


00:38:41.000 --> 00:38:42.470
the S atmosphere each of these


00:38:42.480 --> 00:38:44.230
generation one satellites is several


00:38:44.240 --> 00:38:47.270
hundred kilos of material so when you've


00:38:47.280 --> 00:38:48.910
got five of them coming in a day that's


00:38:48.920 --> 00:38:51.470
a couple of tons of material being a


00:38:51.480 --> 00:38:53.950
bled and added to the atmosphere mainly


00:38:53.960 --> 00:38:55.270
in the form of heavy


00:38:55.280 --> 00:38:58.109
metals there is a fact that I've pulled


00:38:58.119 --> 00:38:59.630
out of an interesting article India


00:38:59.640 --> 00:39:01.349
Today of all places have got a fairly


00:39:01.359 --> 00:39:03.630
good article about this and one thing


00:39:03.640 --> 00:39:05.990
they point out is that each individual


00:39:06.000 --> 00:39:07.670
one of these generation one St


00:39:07.680 --> 00:39:09.150
satellites when it burns up in the


00:39:09.160 --> 00:39:11.670
atmosphere when it a blades deposits


00:39:11.680 --> 00:39:15.470
about 30 kilos of aluminium oxide into


00:39:15.480 --> 00:39:16.990
the upper atmosphere about where the


00:39:17.000 --> 00:39:19.550
ozone layer is now that's a problem


00:39:19.560 --> 00:39:21.790
because aluminium oxide is a compound


00:39:21.800 --> 00:39:24.069
that is known to be very devastating to


00:39:24.079 --> 00:39:26.710
the ozone layer it's a real problem now


00:39:26.720 --> 00:39:29.510
if each s is dumping 30 kg into the


00:39:29.520 --> 00:39:31.550
atmosphere that has the potential to


00:39:31.560 --> 00:39:34.190
destroy a large amount of ozone if


00:39:34.200 --> 00:39:35.990
you're suddenly dumping five of them in


00:39:36.000 --> 00:39:40.190
per day that's 150 kilos per day if you


00:39:40.200 --> 00:39:43.390
go up to the 25 obviously that goes up


00:39:43.400 --> 00:39:46.550
again from 150 kilos to what 5 time 150


00:39:46.560 --> 00:39:47.309
is


00:39:47.319 --> 00:39:51.109
750 nil your ton of aluminium oxide per


00:39:51.119 --> 00:39:53.589
day something that can damage the oone L


00:39:53.599 --> 00:39:55.390
and we've only just got out of the time


00:39:55.400 --> 00:39:56.790
where we did an incredible job of


00:39:56.800 --> 00:39:58.990
preventing is killing the ozone layer


00:39:59.000 --> 00:40:01.550
yeah we're about to start it again


00:40:01.560 --> 00:40:03.510
people have tried to do some


00:40:03.520 --> 00:40:05.349
computational studies of the effects of


00:40:05.359 --> 00:40:06.790
adding all this metal to the upper


00:40:06.800 --> 00:40:08.790
atmosphere and nobody really knows


00:40:08.800 --> 00:40:10.630
what's going to happen some Studies have


00:40:10.640 --> 00:40:13.349
said that it could accidentally help to


00:40:13.359 --> 00:40:14.990
slightly mitigate climate change but it


00:40:15.000 --> 00:40:16.589
might increase the albo of the a


00:40:16.599 --> 00:40:18.150
atmosphere it might cause more clouds to


00:40:18.160 --> 00:40:20.190
form so it could reflect a bit more


00:40:20.200 --> 00:40:22.430
sunlight or could be good but other


00:40:22.440 --> 00:40:24.069
Studies have suggested the opposite that


00:40:24.079 --> 00:40:25.270
it could actually lower the amount of


00:40:25.280 --> 00:40:27.790
clouds we've got and also a bit more


00:40:27.800 --> 00:40:30.349
Greenhouse nastiness to the mix so it


00:40:30.359 --> 00:40:31.790
could have an impact on our climate we


00:40:31.800 --> 00:40:33.230
don't know which way it'll go it could


00:40:33.240 --> 00:40:35.710
have an impact on the ozone layer we


00:40:35.720 --> 00:40:37.309
just don't know yet and so what's


00:40:37.319 --> 00:40:39.790
happening with this is we're effectively


00:40:39.800 --> 00:40:41.349
running a science experiment like the


00:40:41.359 --> 00:40:42.790
ones you do in the lab the ones you do


00:40:42.800 --> 00:40:45.430
at school without ever done it without


00:40:45.440 --> 00:40:47.589
ever having done it before and we're


00:40:47.599 --> 00:40:49.430
running it on the planet that is our own


00:40:49.440 --> 00:40:52.470
home so I guess it's a bit like you know


00:40:52.480 --> 00:40:54.390
you've got two unruly toddlers running


00:40:54.400 --> 00:40:57.349
around with um insects cray like the


00:40:57.359 --> 00:40:58.510
stuff you've got to get rid of the


00:40:58.520 --> 00:41:01.069
mosquitoes yeah running around emptying


00:41:01.079 --> 00:41:02.670
can after can of that in your house and


00:41:02.680 --> 00:41:03.950
you're just saying yeah well let's do it


00:41:03.960 --> 00:41:05.270
what's the worst that can happen and you


00:41:05.280 --> 00:41:09.230
just don't know yeah uh 42,000


00:41:09.240 --> 00:41:10.750
satellites when they're ultimately all


00:41:10.760 --> 00:41:12.470
up there coming back down into the


00:41:12.480 --> 00:41:16.109
atmosphere we'll deposit 1.26 million


00:41:16.119 --> 00:41:19.950
kilograms of aluminium oxide so and


00:41:19.960 --> 00:41:21.950
that's going to be continuous because


00:41:21.960 --> 00:41:23.870
they it's not just


00:41:23.880 --> 00:41:26.109
42,000 as they come down they'll replace


00:41:26.119 --> 00:41:29.069
them and add more to get to their full


00:41:29.079 --> 00:41:32.349
structure so it'll be an ongoing thing


00:41:32.359 --> 00:41:34.349
multiplied by however many


00:41:34.359 --> 00:41:36.309
constellations are created to do the


00:41:36.319 --> 00:41:38.710
same thing so but it isn't also like


00:41:38.720 --> 00:41:40.430
that is easily recoverable that's a lot


00:41:40.440 --> 00:41:43.069
of resources that we're just losing yeah


00:41:43.079 --> 00:41:46.030
exactly um now I could imagine a much


00:41:46.040 --> 00:41:47.910
further future where instead of things


00:41:47.920 --> 00:41:50.550
being retired by deorbiting them you


00:41:50.560 --> 00:41:52.430
retire them by boosting them to kind of


00:41:52.440 --> 00:41:54.230
graveyard orbits and have something


00:41:54.240 --> 00:41:55.870
there collecting them and melting them


00:41:55.880 --> 00:41:58.109
down for the materials H but that's why


00:41:58.119 --> 00:41:59.430
in the future because that will be a lot


00:41:59.440 --> 00:42:01.470
more expensive it's cheaper at the


00:42:01.480 --> 00:42:03.550
minute to just throw them away I mean we


00:42:03.560 --> 00:42:05.309
see with recycling efforts that there's


00:42:05.319 --> 00:42:07.910
not much motivation to recycle when


00:42:07.920 --> 00:42:10.710
making things from new products is still


00:42:10.720 --> 00:42:13.230
cheaper yeah well if I could solve the


00:42:13.240 --> 00:42:16.270
latency problem that would maybe help


00:42:16.280 --> 00:42:18.550
cure it as well but how do you do that


00:42:18.560 --> 00:42:20.670
relay stations on Earth I don't know I


00:42:20.680 --> 00:42:23.150
don't know but uh yeah that that's a


00:42:23.160 --> 00:42:25.030
really fascinating story I know Fred and


00:42:25.040 --> 00:42:26.349
I have talked about it before but it's


00:42:26.359 --> 00:42:28.349
worth revisiting and uh yeah the


00:42:28.359 --> 00:42:31.470
information just keeps evolving over


00:42:31.480 --> 00:42:34.990
time and we're not nearly at capacity


00:42:35.000 --> 00:42:36.630
yet with these constellations if you'd


00:42:36.640 --> 00:42:39.349
like to read it uh as jonty said it's uh


00:42:39.359 --> 00:42:42.190
on the website


00:42:42.200 --> 00:42:44.549
indiatoday.in that brings us to the end


00:42:44.559 --> 00:42:45.910
of the show don't forget to visit our


00:42:45.920 --> 00:42:48.030
website or our social media sites plenty


00:42:48.040 --> 00:42:50.710
of things to see and do there uh if you


00:42:50.720 --> 00:42:52.030
have any thoughts on any of the things


00:42:52.040 --> 00:42:54.230
we've discussed by all means uh send us


00:42:54.240 --> 00:42:56.150
a message via our website just there's a


00:42:56.160 --> 00:42:59.630
little button up top of our homepage um


00:42:59.640 --> 00:43:02.069
AMA where you can send us messages and


00:43:02.079 --> 00:43:04.349
audio questions or whatever you like


00:43:04.359 --> 00:43:05.829
Space Nuts


00:43:05.839 --> 00:43:09.950
podcast.com or SPAC nuts. is the place


00:43:09.960 --> 00:43:12.750
to go John D thank you so much we're at


00:43:12.760 --> 00:43:14.150
the end we'll catch up with you real


00:43:14.160 --> 00:43:16.390
soon it's absolute pleasure thank you


00:43:16.400 --> 00:43:18.670
for having me uh Johny Horner professor


00:43:18.680 --> 00:43:20.349
of astrophysics at the University of


00:43:20.359 --> 00:43:22.069
Southern Queensland thanks to Hugh in


00:43:22.079 --> 00:43:25.309
the studio who um well he he couldn't be


00:43:25.319 --> 00:43:27.870
with us today cuz he got hit by a piece


00:43:27.880 --> 00:43:29.630
of SpaceX


00:43:29.640 --> 00:43:33.150
satellite uh no no he didn't maybe he


00:43:33.160 --> 00:43:34.390
did I don't know I've been seen it for


00:43:34.400 --> 00:43:36.390
ages and from me Andrew Dunley thanks


00:43:36.400 --> 00:43:37.750
very much for your company we'll catch


00:43:37.760 --> 00:43:40.349
you on the next episode of Space Nuts


00:43:40.359 --> 00:43:42.950
bye for now Space Nuts you'll be


00:43:42.960 --> 00:43:45.829
listening to the Space Nuts


00:43:45.839 --> 00:43:48.910
podcast available at Apple podcasts


00:43:48.920 --> 00:43:51.910
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00:43:51.920 --> 00:43:54.150
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00:43:54.160 --> 00:43:56.790
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00:43:56.800 --> 00:43:58.990
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00:43:59.000 --> 00:44:02.280
from ds.com