Black Holes, Light Speed & Oceanic Exoplanets: #498 - Diving Deep into Your Space Queries |...

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Language: en

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hello again thanks for joining us this


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is a Q&A edition of Space Nuts this is


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where the audience asks us questions and


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we refer to somebody else and uh in


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today's episode we are going to talk


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about uh whether or not we can see our


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own reflection in space that's a


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question from Tony are we living in a


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holographic Universe Charles wants to


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know David is asking about black holes


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versus light who wins that war and


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Duncan liquid planets are there any out


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there we'll find out on this episode of


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Space Nuts 15 seconds guidance is


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internal 10 9 ignition sequence start


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Space Nuts 5 4 3 2 1 2 3 4 5 5 Space


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Nuts asut report feels good and joining


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us to sort all of that out is Professor


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jonty Horner from the University of


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Southern Queensland hi JY good afternoon


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how you doing I'm good it's feels like a


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second since we last spoke absolutely


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time flies when you're having fun I


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think that's


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say h let's um muck in as they say in


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your part of the world uh let's uh go to


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our first question this one comes from


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uh


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Tony um hi guys given the cosmos has


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black holes gravity waves uh


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gravitational lensing uh light echos and


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dust cloud Reflections any chance we


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could ever see a reflection of our Milky


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Way Galaxy love the show Tony from


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Merrickville which is a suburb of Sydney


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thanks Tony what are your thoughts jny I


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think there's a short answer a long


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answer to this I think the short answer


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is I can think of nowhere that we could


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get a resolved image you know so we're


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not going to get something like a mirror


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held up to reality where we get a


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beautiful picture of the Milky Way


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galaxy reflected back to us the


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different phenomena that can bend light


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and change its


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direction are often Le to the amount of


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mass so you've got a black hole or a


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star or something like that and under


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Einstein Ser general relativity the idea


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is that mass curve space so like tries


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to go in what it thinks is a straight


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straight line but because the space is


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curved it gets deflected by Falling the


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shortest path through the curved space


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so that's how you get gravitational


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lensing how you get light being bent now


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light's traveling really really quickly


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so nearly all the time that deflection


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is relatively small you're not talking


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about light changing through 90 degrees


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you're talking about it changing through


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a few degrees at most yeah and that kind


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of you could link to the idea of the


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skap Velocity in order to get it


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changing through a really substantial


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Direction you'd have to be very close


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into a black hole or something like that


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and at that point you're almost falling


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into the black hole and everything is


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doomed so you need to set up a


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really unusual set of circumstances for


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some light from the Milky Way to be bent


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by let's say three or four degrees by


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one source and then go to another source


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and be bent again and again and again


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that chain of events would probably get


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only a tiny tiny little bit so I think


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you could imagine a scenario where there


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are packets of light photons from the


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Milky Way that get back to the Milky Way


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and that mechanism but there'd be barely


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any and we wouldn't really be able to


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detect them if there were any at all if


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there were dust clouds near the Milky


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Way some of the light from the Milky Way


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would reflect off them and this is like


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the beautiful reflection nebuli we see


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all doed through our galaxy the things


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that we get fabul asra photos of now I


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was Imaging doing some asro photography


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a few months ago the large and the small


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maganic


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clouds and learning a new photograph


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processing tool that friends of mine who


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were incredibly gifted asra


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photographers taught me how to use and


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playing with that and stretching and


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bending and


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fiddling there's a persistent feature


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around the maganic cloud that looks like


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dust that appears to be structured that


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I thought was I've overdone it on the


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image and then I looked at a different


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image and the same structures were there


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at the same time so there's clearly dust


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and gas that has been stripped off the


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large melanic Cloud by the Milky


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Way that is illuminated enough that it


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is brighter than the background pitch


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black of the sky for my camera to pick


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it up that means that there is light


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hitting that and bouncing back to us to


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see it and some fraction of that light


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will be light from the Milky Way now I


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don't know enough about that Deb I've


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not been able to find much discussion


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online cuz I was fascinated when I saw


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it on these photos


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repeatedly um but I would Hazard that


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some of the light that is Illuminating


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this gas and dust that is around the


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large maganic cloud is light from the


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Milky Way reflected back to us but that


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isn't anywhere near enough to get an


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image it's a bit like when you're


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looking on a really foggy day and the


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sky is really bright you can't see an


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image of the Sun from that light you


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just got light scattered at you in all


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directions yeah lost all of the


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information so I think we do get


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reflected light from the Milky Way going


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back and things like that but to


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actually get an image a reflected image


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like you see the mirror that to me is


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beyond the bounds of possibility the


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nearest we'll get is finding galaxies


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that look very similar to our own so


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they give us a perspective of what we


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would look like from the outside yeah


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this is one of Fred's great wishes if we


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were asked a question not so long ago uh


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you if you could do anything if you


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could just take a spacecraft anywhere in


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the universe and look at something that


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you want to see what would it be and and


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Fred's wish was to go outside of our


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galaxy so he could look at it and see


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exactly what shape it was we we have a


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pretty good idea but we've we've never


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been able to image it we don't know for


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sure if it's got the number of spiral


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arms that they assume it's got or


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anything like that um so that was Fred's


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you know if you could do anything just


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the snap of his fingers looking at our


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our galaxy from outside was was one of


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his wishes so Tony unfortunately no we


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cannot see a reflection of our galaxy in


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any way or form we probably are seeing


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light bounc back to us as jonty was


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explaining um from our own Galaxy but it


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certainly wouldn't give us an image but


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thanks for the question great to hear


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from you our next question comes from


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Charles this is a short sweet but uh


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rather difficult one to answer uh what


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do you think of the theory that we live


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in a holographic Universe now this is


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something I've seen popping up time and


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time again in the popular press and I


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suppose we should explain what a


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holographic universe is before we decide


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whether or not we live in one yeah and


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this is one of the ones that breaks my


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head so your answer to this will be


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neither um good or accurate I suspect


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because this is far from my a of EXP but


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I'll do my best the holographic Universe


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stuff is tied to string theory is my


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understanding and to me is at the point


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where you're bordering along the


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boundary between science and philosophy


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because you're starting to ask questions


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that we have no way of testing yet and


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that's really hard now this all ties


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down to very mathematical and very


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theoretical studies of the Universe I


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think getting back to about the 1990s


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where people found that in some versions


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of the mass of string theory you can get


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threedimensional stuff being represented


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in a two-dimensional way without losing


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any


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data um and it's an answer to some of


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the issues to do with information and


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black holes it's one of the things that


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led people to suggest that you can get


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information that goes into black holes


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is not lost but might be stored in the


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Event Horizon and all these kind of


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things now my understanding of it as you


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can tell by that explanation is kind of


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limited it's not my area of expertise it


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is called the holographic principle and


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that leads to the idea of the


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holographic universe so the idea that


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you can get essentially a


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two-dimensional representation of all


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the data you need to have a


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three-dimensional thing means that you


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could have in some


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way a three-dimensional appearing thing


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actually only be twood dimensional a


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holograph essentially so that's what the


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holograph is all about and I'm I fully


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understand that you can tell by the


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explanation it's interesting it's become


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sufficiently rooted in popular


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Consciousness and this is a turtle


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turtle um detour here but one of the


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kinds of music I really like to listen


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to is a genre called symphonic metal


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which is bit bizarre it's kind of


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operatic Rock if you think about the


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kind of stuff Queen were doing and got a


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little bit more Rocky a little bit more


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metal and that's like that so you


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typically have an operatically Trend


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soprano singing the two biggest groups


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of that that I listen to quite a lot are


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groups called Nightwish and EPA and


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Nightwish have done a couple of science


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sced albums where they talk about the


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origin of life and philosophy and Origin


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of Species and all sorts of stuff like


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that one of their tracks which I try and


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get on the radio occasionally when I do


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a chat about asteroids is a tribute to


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the great scientist Eugene Shoemaker who


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whose ashes were put onto a spacecraft


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to the Moon who discovered the comic


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that hit Jupiter back in 1994 so that's


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might wish Epica have an album named the


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holographic


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principle which they've always done


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slightly quirky projects as well the


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fact that this concept this thing that


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is at the very bound extreme bounds of


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theoretical physics and theoretical


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cosmology has become sufficiently


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culturally embedded that rock groups are


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naming albums after it is kind of quirky


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for me and it shows that it's not a


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totally brand new idea it's if it was


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certainly brand new it wouldn't be in


00:10:01.560 --> 00:10:04.590
the popular Consciousness yet it does


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make my head hurt I will wholeheartedly


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and happily admit that this is not


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something where I'm an expert you know


00:10:12.240 --> 00:10:14.790
in any way shape or form there are very


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detailed discussions of it online even


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if you pull up the Wikipedia page the


00:10:19.200 --> 00:10:22.269
Wikipedia page is pretty lengthy and


00:10:22.279 --> 00:10:24.150
links to a lot of references talks about


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some of the discussions people have had


00:10:25.800 --> 00:10:28.509
about it talks about information density


00:10:28.519 --> 00:10:30.509
the people whove proposed OS all these


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ideas um gives you links to other places


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now I know certainly when I'm teaching I


00:10:35.079 --> 00:10:36.910
have to tell people that Wikipedia is


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not the be and


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Endor it's a fluid resource it's subject


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to change and it's subject to being


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incorrect but with a lot of these topics


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in the more theoretical parts of


00:10:47.200 --> 00:10:49.150
astrophysics or even for astronomy as a


00:10:49.160 --> 00:10:50.750
whole Wikipedia tends to be really


00:10:50.760 --> 00:10:52.470
pretty good because there's enough


00:10:52.480 --> 00:10:54.110
people out there who are really


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fascinated by the field that when they


00:10:56.519 --> 00:10:58.069
see something wrong they'll fix it the


00:10:58.079 --> 00:10:59.509
errors don't tend to hang around that


00:10:59.519 --> 00:11:01.389
one so it tends to actually be a good


00:11:01.399 --> 00:11:02.910
first resource so long as it's not your


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only resource and the article there


00:11:05.200 --> 00:11:07.870
about the holographic principle also


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links to these two albums by different


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groups that have had the same name but


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has a fairly lengthy discussion of a lot


00:11:14.160 --> 00:11:16.750
of the um different ideas behind this a


00:11:16.760 --> 00:11:19.790
few links to different types of theorems


00:11:19.800 --> 00:11:22.310
that are tied to this and also a good


00:11:22.320 --> 00:11:24.550
list of 28 references and a couple of


00:11:24.560 --> 00:11:26.389
results on top of that including Journal


00:11:26.399 --> 00:11:28.629
papers where if you really want to dive


00:11:28.639 --> 00:11:32.430
into this can do um will be very quickly


00:11:32.440 --> 00:11:34.069
apparent to you that by reading it for


00:11:34.079 --> 00:11:35.509
five minutes you already know more about


00:11:35.519 --> 00:11:37.350
it than I do and then listen back to


00:11:37.360 --> 00:11:39.230
this answer from point out every way in


00:11:39.240 --> 00:11:42.870
which I was wrong here but that's my


00:11:42.880 --> 00:11:45.310
take on it now with all that said to get


00:11:45.320 --> 00:11:46.590
back to the question what do I think


00:11:46.600 --> 00:11:48.470
about the theory I think I don't think


00:11:48.480 --> 00:11:50.030
about it very much because it makes my


00:11:50.040 --> 00:11:52.069
head hurt but as I say I think it gets


00:11:52.079 --> 00:11:54.949
to the point of philosophy it's if there


00:11:54.959 --> 00:11:57.350
is something where you can make no


00:11:57.360 --> 00:11:59.230
testable measurement to differentiate


00:11:59.240 --> 00:12:01.350
between two different ideas you're more


00:12:01.360 --> 00:12:02.949
in the bounds of philosophy than you are


00:12:02.959 --> 00:12:06.069
in the bounds of Science and it's a bit


00:12:06.079 --> 00:12:07.670
like that old chest of how do I know


00:12:07.680 --> 00:12:09.990
that anybody else actually exists the


00:12:10.000 --> 00:12:12.350
only perception the only existence I'm


00:12:12.360 --> 00:12:14.990
aware of is my own existence I'm aware


00:12:15.000 --> 00:12:17.310
of my inner dialogue and I'm aware of


00:12:17.320 --> 00:12:19.470
what I see and perceive and we


00:12:19.480 --> 00:12:21.910
implicitly assume that everybody we talk


00:12:21.920 --> 00:12:24.590
to is a being like us but it could


00:12:24.600 --> 00:12:26.910
equally just be a convenient fiction and


00:12:26.920 --> 00:12:28.949
I could be entirely locked in my own


00:12:28.959 --> 00:12:30.509
head having all this is a kind of weird


00:12:30.519 --> 00:12:32.310
dream I mean I'd argue that this


00:12:32.320 --> 00:12:33.910
question is a good example of the fact


00:12:33.920 --> 00:12:35.150
that I'm not just lock in my own head


00:12:35.160 --> 00:12:36.230
and having a weird dream because I would


00:12:36.240 --> 00:12:37.750
have never thought of this question


00:12:37.760 --> 00:12:41.470
myself but you start getting to points


00:12:41.480 --> 00:12:44.269
where you are having an argument that is


00:12:44.279 --> 00:12:46.310
more one of philosophy than it is one of


00:12:46.320 --> 00:12:48.870
Science and for me the thing that


00:12:48.880 --> 00:12:51.430
differentiates the two comes down to


00:12:51.440 --> 00:12:53.790
prediction and testing of theories if


00:12:53.800 --> 00:12:56.389
you have a theory that is new it should


00:12:56.399 --> 00:12:58.430
make testable predictions and I'm not


00:12:58.440 --> 00:13:00.189
really sure because I'm not a


00:13:00.199 --> 00:13:02.069
theoretical cosmologist or a theoretical


00:13:02.079 --> 00:13:04.389
physicist if this does and if it does


00:13:04.399 --> 00:13:07.230
how they would work so for me then I


00:13:07.240 --> 00:13:08.710
come back to kind of the okam draer


00:13:08.720 --> 00:13:10.470
thing with a lack of knowledge with a


00:13:10.480 --> 00:13:12.629
lack of expertise the simplest


00:13:12.639 --> 00:13:14.710
explanation to me is just that we are in


00:13:14.720 --> 00:13:16.069
the universe we


00:13:16.079 --> 00:13:18.389
see but it's really fascinating to look


00:13:18.399 --> 00:13:19.949
into this it's important to do this kind


00:13:19.959 --> 00:13:22.269
of work I'm just not qualified to do it


00:13:22.279 --> 00:13:24.590
I don't have the expertise yeah it sort


00:13:24.600 --> 00:13:28.230
of connects with another theory that we


00:13:28.240 --> 00:13:30.269
have created this universe in their own


00:13:30.279 --> 00:13:34.910
minds as a collective uh we you know the


00:13:34.920 --> 00:13:36.710
physical existence of the universe is a


00:13:36.720 --> 00:13:40.030
manifestation of us yeah um I've I've


00:13:40.040 --> 00:13:42.189
heard that one before which is an


00:13:42.199 --> 00:13:43.910
interesting one tied to it is simulation


00:13:43.920 --> 00:13:45.629
Theory which I've also seen musical


00:13:45.639 --> 00:13:47.910
albums named after which is the idea


00:13:47.920 --> 00:13:49.670
that what we live in is a simulation and


00:13:49.680 --> 00:13:52.110
it's extrapolating off Mo's law and


00:13:52.120 --> 00:13:53.910
similar laws about computing power


00:13:53.920 --> 00:13:56.870
increasing into the future which is that


00:13:56.880 --> 00:13:58.430
whilst the universe is infinitely


00:13:58.440 --> 00:14:00.310
complex amount of computing power you


00:14:00.320 --> 00:14:03.150
would need to fully simulate a universe


00:14:03.160 --> 00:14:05.269
is not as high as you would think


00:14:05.279 --> 00:14:06.870
particularly if you set up your code so


00:14:06.880 --> 00:14:08.230
you only simulate the bits that have


00:14:08.240 --> 00:14:10.990
been observed at a time you know you


00:14:11.000 --> 00:14:12.430
don't need to for example if you were


00:14:12.440 --> 00:14:13.790
simulating the Earth and everything you


00:14:13.800 --> 00:14:15.990
wouldn't need to simulate the surface of


00:14:16.000 --> 00:14:17.629
these exop planets we've discovered yet


00:14:17.639 --> 00:14:19.110
because we don't have the ability to see


00:14:19.120 --> 00:14:20.870
them so you serve a huge amount in


00:14:20.880 --> 00:14:22.670
processing so that leads to this


00:14:22.680 --> 00:14:24.069
argument that you could set up a


00:14:24.079 --> 00:14:26.829
simulation with the quality of fidelity


00:14:26.839 --> 00:14:29.310
that we couldn't know the difference


00:14:29.320 --> 00:14:31.389
simulation Theory then goes to one step


00:14:31.399 --> 00:14:33.590
further and says if you can do that once


00:14:33.600 --> 00:14:35.030
it's only a small step from being able


00:14:35.040 --> 00:14:36.509
to do something once to being able to do


00:14:36.519 --> 00:14:38.910
it many many towns so therefore


00:14:38.920 --> 00:14:40.590
statistically it becomes more likely


00:14:40.600 --> 00:14:42.230
that we live in a simulation rather than


00:14:42.240 --> 00:14:44.189
the real world because there'll be


00:14:44.199 --> 00:14:45.910
millions of universes and only one of


00:14:45.920 --> 00:14:47.990
them will be real and it's fascinating


00:14:48.000 --> 00:14:49.389
it's really good fun but again it's


00:14:49.399 --> 00:14:51.749
philosophy because how do we test this


00:14:51.759 --> 00:14:53.949
unless we get to take the pill and step


00:14:53.959 --> 00:14:55.749
out of the Matrix and see it for what it


00:14:55.759 --> 00:14:59.110
is how you test between these things is


00:14:59.120 --> 00:15:01.030
really the challenge for me to make them


00:15:01.040 --> 00:15:03.350
into a really scientific discuss rather


00:15:03.360 --> 00:15:06.230
than a philosophical one yeah uh The


00:15:06.240 --> 00:15:09.790
Matrix was a good film in in a


00:15:09.800 --> 00:15:12.870
constructed universe and the reality was


00:15:12.880 --> 00:15:15.550
much more horrifying but uh yeah great


00:15:15.560 --> 00:15:18.030
question and um yeah I think that's one


00:15:18.040 --> 00:15:20.710
that'll be de debated for years to come


00:15:20.720 --> 00:15:23.310
thanks Charles this is Space Nuts uh


00:15:23.320 --> 00:15:26.629
Andrew Dunley here with Professor jonty


00:15:26.639 --> 00:15:28.629
hona let's take a little break from the


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incognet now back to the


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show and I feel fine Space Nuts okay um


00:17:28.400 --> 00:17:31.070
Johny Let's uh do some audio questions


00:17:31.080 --> 00:17:33.230
and this one I I thought we'd done but I


00:17:33.240 --> 00:17:36.430
remember I did send it to you in name


00:17:36.440 --> 00:17:38.190
but I sent you the wrong audio so we did


00:17:38.200 --> 00:17:40.190
the other one and so this is the


00:17:40.200 --> 00:17:41.789
question I meant to send you a couple of


00:17:41.799 --> 00:17:43.990
weeks ago from David this is David from


00:17:44.000 --> 00:17:45.070
zagen


00:17:45.080 --> 00:17:47.350
Texas uh I got another question about


00:17:47.360 --> 00:17:49.470
black holes just like all my other


00:17:49.480 --> 00:17:51.710
questions I was listening to the latest


00:17:51.720 --> 00:17:54.230
episode and you were talking about light


00:17:54.240 --> 00:17:58.270
spinning around black holes um andless


00:17:58.280 --> 00:18:00.470
being able to see the the effects later


00:18:00.480 --> 00:18:02.990
than when the the event actually


00:18:03.000 --> 00:18:07.350
happened but that got me thinking if the


00:18:07.360 --> 00:18:09.789
light goes around the black hole and


00:18:09.799 --> 00:18:12.029
then starts to slowly get sucked


00:18:12.039 --> 00:18:15.950
in would the additional gravity of the


00:18:15.960 --> 00:18:18.870
black hole pulling on the light increase


00:18:18.880 --> 00:18:20.789
the speed of the light any faster than


00:18:20.799 --> 00:18:23.350
the speed of light or even at all


00:18:23.360 --> 00:18:24.990
because I know when a ballet dancer is


00:18:25.000 --> 00:18:26.830
spinning and she pulls her arms in she


00:18:26.840 --> 00:18:30.470
spins faster so so would that effect be


00:18:30.480 --> 00:18:33.230
the same on light spinning around the


00:18:33.240 --> 00:18:35.270
black hole and then getting sucked


00:18:35.280 --> 00:18:38.750
in um I'm not really sure how that works


00:18:38.760 --> 00:18:41.190
with light considering it has no Mass


00:18:41.200 --> 00:18:43.350
but I appreciate if youall answer my


00:18:43.360 --> 00:18:46.390
question thank you good on you David uh


00:18:46.400 --> 00:18:48.350
I'm pretty sure ballerinas don't spin at


00:18:48.360 --> 00:18:49.950
the speed of light


00:18:49.960 --> 00:18:53.270
but could be wrong uh they do spin


00:18:53.280 --> 00:18:55.590
rather remarkably uh yeah look this is


00:18:55.600 --> 00:18:59.110
an interesting one um light is the fast


00:18:59.120 --> 00:19:01.750
thing in the universe I venture to say


00:19:01.760 --> 00:19:05.510
and I think in conversations Fred and I


00:19:05.520 --> 00:19:07.710
have had in the past that nothing goes


00:19:07.720 --> 00:19:10.110
faster than the speed of light in a


00:19:10.120 --> 00:19:13.789
vacuum so I would imagine the answer is


00:19:13.799 --> 00:19:16.310
probably no that the black hole can't


00:19:16.320 --> 00:19:18.190
make light go faster than the speed of


00:19:18.200 --> 00:19:20.470
light it doesn't change the speed of


00:19:20.480 --> 00:19:23.750
light it changed its direction and if


00:19:23.760 --> 00:19:26.310
you change the energy of


00:19:26.320 --> 00:19:28.750
light because you can't change the speed


00:19:28.760 --> 00:19:30.830
what you change is the frequency and the


00:19:30.840 --> 00:19:33.470
wavelength so if light is trying to


00:19:33.480 --> 00:19:37.350
escape from a mass then you see a thing


00:19:37.360 --> 00:19:39.870
called gravitational red shift so light


00:19:39.880 --> 00:19:42.390
coming up from the surface of the sun


00:19:42.400 --> 00:19:44.669
will be red shifted a tiny little bit


00:19:44.679 --> 00:19:45.870
because it's escaping from the


00:19:45.880 --> 00:19:47.990
gravitational well of the sun similarly


00:19:48.000 --> 00:19:49.549
if it was falling inwards you'd expect


00:19:49.559 --> 00:19:51.310
it to be slightly blue shifted but it's


00:19:51.320 --> 00:19:54.430
a very very small imperceptible thing um


00:19:54.440 --> 00:19:55.870
in terms of the speed of light being the


00:19:55.880 --> 00:19:57.990
fastest thing there is that's where all


00:19:58.000 --> 00:19:59.390
our models of the Universe and


00:19:59.400 --> 00:20:02.590
Everything sits and Terry praet in one


00:20:02.600 --> 00:20:04.510
of the many bqu world books that I love


00:20:04.520 --> 00:20:06.230
very well made the point that Darkness


00:20:06.240 --> 00:20:08.390
must travel faster than light because


00:20:08.400 --> 00:20:09.870
whenever you turn on light it was


00:20:09.880 --> 00:20:12.950
already dark I think is quite nice and


00:20:12.960 --> 00:20:15.830
poetic but in reality it seems that the


00:20:15.840 --> 00:20:17.750
speed of light in all of the models we


00:20:17.760 --> 00:20:20.110
have of the inves cosmology is this kind


00:20:20.120 --> 00:20:21.070
of


00:20:21.080 --> 00:20:23.669
inviolable speed limit of the universe


00:20:23.679 --> 00:20:25.430
now might be that when we have a chat in


00:20:25.440 --> 00:20:27.430
20 years time that a change to tell


00:20:27.440 --> 00:20:29.149
because that's how science works


00:20:29.159 --> 00:20:32.110
works but at the minute the speed of


00:20:32.120 --> 00:20:34.230
light is a speed of light and there is


00:20:34.240 --> 00:20:35.909
an implicit thing there that we never


00:20:35.919 --> 00:20:37.070
mentioned that we should do that what


00:20:37.080 --> 00:20:38.270
we're actually talking about there is


00:20:38.280 --> 00:20:40.310
the speed of the light in the vacuum of


00:20:40.320 --> 00:20:42.750
space yeah so as soon as light passes


00:20:42.760 --> 00:20:44.549
into a medium it slows down and that's


00:20:44.559 --> 00:20:47.230
why you get refraction if light goes


00:20:47.240 --> 00:20:50.270
from air into water the speed of light


00:20:50.280 --> 00:20:51.870
in water is slower than the speed of


00:20:51.880 --> 00:20:54.270
light in air that's why you get the


00:20:54.280 --> 00:20:56.870
bending the change of Direction there


00:20:56.880 --> 00:20:59.110
with black HS what's actually happening


00:20:59.120 --> 00:21:01.470
is that the black hole is bending space


00:21:01.480 --> 00:21:03.070
and the light is following a straight


00:21:03.080 --> 00:21:05.310
path on a curved surface so it appears


00:21:05.320 --> 00:21:08.070
to bend which is subtly different


00:21:08.080 --> 00:21:10.070
essentially light falling into a black


00:21:10.080 --> 00:21:12.549
hole if you could imagine being just


00:21:12.559 --> 00:21:16.230
outside the Event Horizon so you're not


00:21:16.240 --> 00:21:18.789
dead and you're looking outwards the


00:21:18.799 --> 00:21:20.310
things you were looking at would look a


00:21:20.320 --> 00:21:22.630
little bit Bluer Than they actually are


00:21:22.640 --> 00:21:24.190
because light falling in is getting blue


00:21:24.200 --> 00:21:26.149
shifted as it comes towards you


00:21:26.159 --> 00:21:29.870
similarly if you sha a yellow light or a


00:21:29.880 --> 00:21:31.510
green light laser I've got one of those


00:21:31.520 --> 00:21:33.070
when I do Outreach sometimes to point


00:21:33.080 --> 00:21:35.070
the stars out if I sh a green light


00:21:35.080 --> 00:21:36.990
laser out from Near The Event Horizon of


00:21:37.000 --> 00:21:38.269
the black ho the light would still


00:21:38.279 --> 00:21:40.789
Escape be some outside the Event Horizon


00:21:40.799 --> 00:21:42.510
so the escape Velocity is lower than the


00:21:42.520 --> 00:21:45.470
speed of light there's an acceleration


00:21:45.480 --> 00:21:47.830
pulling back the speed of the light


00:21:47.840 --> 00:21:49.310
cannot change but the energy would


00:21:49.320 --> 00:21:50.470
change so it would become


00:21:50.480 --> 00:21:52.630
gravitationally red shifted so that


00:21:52.640 --> 00:21:55.430
green light laser would look redder to


00:21:55.440 --> 00:21:57.870
The Observer Way Beyond the black hole


00:21:57.880 --> 00:21:59.990
than it would as it leaves in my hand


00:22:00.000 --> 00:22:01.669
where I'm in the shared rest frame for


00:22:01.679 --> 00:22:04.110
it but the speed of light itself would


00:22:04.120 --> 00:22:05.390
not be


00:22:05.400 --> 00:22:08.110
changing cavat if the black hole's got a


00:22:08.120 --> 00:22:09.630
disc of material around it if it's got


00:22:09.640 --> 00:22:10.789
material around it then you're not


00:22:10.799 --> 00:22:12.909
moving through a perfect vacuum so you


00:22:12.919 --> 00:22:14.549
would see a little bit of a change in


00:22:14.559 --> 00:22:17.110
speed there but that is a different


00:22:17.120 --> 00:22:19.549
physical process for a different


00:22:19.559 --> 00:22:22.350
reason but it's worth being complete I


00:22:22.360 --> 00:22:24.950
guess yes yes I suppose so uh the other


00:22:24.960 --> 00:22:26.789
interesting thing about light which


00:22:26.799 --> 00:22:29.029
we've talked about before is that as you


00:22:29.039 --> 00:22:31.789
said it slows down in liquid but light


00:22:31.799 --> 00:22:33.789
going through a glass slows down but


00:22:33.799 --> 00:22:35.590
when it comes out the other side it


00:22:35.600 --> 00:22:37.710
speeds up again yes and that's what it


00:22:37.720 --> 00:22:40.110
bends back in the other direction yeah


00:22:40.120 --> 00:22:43.190
yeah so it's a it's a tricky thing light


00:22:43.200 --> 00:22:45.390
it because we take it for granted we


00:22:45.400 --> 00:22:47.549
need it it's uh something we've adapted


00:22:47.559 --> 00:22:50.230
to on this planet as human beings uh if


00:22:50.240 --> 00:22:51.950
we were to venture to another planet


00:22:51.960 --> 00:22:54.870
with a different kind of star


00:22:54.880 --> 00:22:58.510
um it would be alien to us in more ways


00:22:58.520 --> 00:23:01.029
than we could imagine because we are


00:23:01.039 --> 00:23:04.190
used to a mediumsized star with a


00:23:04.200 --> 00:23:06.590
relatively bright light but if you went


00:23:06.600 --> 00:23:09.750
to a a planet with a uh I don't know a a


00:23:09.760 --> 00:23:13.110
blue star a bright blue star the


00:23:13.120 --> 00:23:14.510
vegetation would be a different color


00:23:14.520 --> 00:23:16.630
because it would be having to do a


00:23:16.640 --> 00:23:17.990
different kind of


00:23:18.000 --> 00:23:21.190
photosynthesis um you'd see things


00:23:21.200 --> 00:23:23.909
differently uh you know there's all


00:23:23.919 --> 00:23:25.669
sorts of weird wonderful things that


00:23:25.679 --> 00:23:28.029
light could do on in other places just


00:23:28.039 --> 00:23:31.510
Theory the moment


00:23:31.520 --> 00:23:35.110
buttion I I've seen these articles about


00:23:35.120 --> 00:23:36.789
a small subset of women who have an


00:23:36.799 --> 00:23:39.230
extra set of cells detecting color in


00:23:39.240 --> 00:23:40.909
their eye which gives them an incredibly


00:23:40.919 --> 00:23:43.470
more granular and fine ability to


00:23:43.480 --> 00:23:45.190
differentiate colors they're like


00:23:45.200 --> 00:23:47.190
they're the visual equivalent of super


00:23:47.200 --> 00:23:50.710
tasters and they can see something that


00:23:50.720 --> 00:23:52.590
to you or I would just look like it's


00:23:52.600 --> 00:23:54.149
certain color they can see the Hues


00:23:54.159 --> 00:23:56.350
within that you equally you see these


00:23:56.360 --> 00:23:58.750
beautiful images of birds that look very


00:23:58.760 --> 00:24:01.269
done and boring to us but then you see a


00:24:01.279 --> 00:24:02.669
visualization of what they would look


00:24:02.679 --> 00:24:03.830
like to another bird and they're


00:24:03.840 --> 00:24:05.549
incredibly colorful and vibrant because


00:24:05.559 --> 00:24:07.710
the birds are seeing frequencies that


00:24:07.720 --> 00:24:10.669
our eyes are not accustomed to similarly


00:24:10.679 --> 00:24:12.190
with bees and things like that seeing


00:24:12.200 --> 00:24:14.789
into the ultraviolet and that will be


00:24:14.799 --> 00:24:18.669
accentuated for objects around you know


00:24:18.679 --> 00:24:20.789
planets around other stars you then get


00:24:20.799 --> 00:24:22.950
The Oddities I have had the pleasure of


00:24:22.960 --> 00:24:24.590
seeing a couple of turtle eclipses of


00:24:24.600 --> 00:24:26.549
the sun one of which I didn't actually


00:24:26.559 --> 00:24:28.389
see because it was cloudy in cans in


00:24:28.399 --> 00:24:30.510
2012 but we saw the buildup and the


00:24:30.520 --> 00:24:32.549
aftermath and the eclipse itself's


00:24:32.559 --> 00:24:34.470
awesome but there's this very weird


00:24:34.480 --> 00:24:36.909
uncanny valley period in the miniatur


00:24:36.919 --> 00:24:38.070
before and the miniaturist after


00:24:38.080 --> 00:24:41.029
totality where the sun is a tiny little


00:24:41.039 --> 00:24:42.510
point because most of it's blocked by


00:24:42.520 --> 00:24:45.310
the moon so instead of having a disc the


00:24:45.320 --> 00:24:46.630
sun gets smaller and smaller until


00:24:46.640 --> 00:24:48.230
you've essentially got a single point of


00:24:48.240 --> 00:24:49.870
light shining nearly as bright as the


00:24:49.880 --> 00:24:52.789
sun and shadows change and the behavior


00:24:52.799 --> 00:24:54.190
of Shadows look


00:24:54.200 --> 00:24:56.190
different when you've got a single point


00:24:56.200 --> 00:24:58.789
source rather than a few source of light


00:24:58.799 --> 00:25:01.149
and that gives everything a very


00:25:01.159 --> 00:25:03.269
uncomfortable slightly unusual feel


00:25:03.279 --> 00:25:05.470
you've got very cool effects like


00:25:05.480 --> 00:25:07.710
standing under a tree and all the leaves


00:25:07.720 --> 00:25:09.669
are blowing and all the gaps between the


00:25:09.679 --> 00:25:11.310
leaves act as pinhole cameras and you


00:25:11.320 --> 00:25:13.149
get images of the Cresent sun on the


00:25:13.159 --> 00:25:15.590
ground which is spectacular wow


00:25:15.600 --> 00:25:17.350
incidentally on the eclipse trip I went


00:25:17.360 --> 00:25:20.909
to um for the exmouth eclipse one of a


00:25:20.919 --> 00:25:22.430
lot of people have a little pinhole


00:25:22.440 --> 00:25:23.830
cameras that they made to image the


00:25:23.840 --> 00:25:26.110
eclipse and one person had a pack of


00:25:26.120 --> 00:25:28.669
jats which are just an Australian cheese


00:25:28.679 --> 00:25:30.990
biscuit and the poles in the biscuits


00:25:31.000 --> 00:25:33.029
were perfect pinhole


00:25:33.039 --> 00:25:35.750
cameras and they had a snack so when the


00:25:35.760 --> 00:25:37.789
equp finished nobody was hungry it was


00:25:37.799 --> 00:25:39.470
absolutely brilliant and I'd never even


00:25:39.480 --> 00:25:41.710
thought of it so you get all these Weir


00:25:41.720 --> 00:25:44.389
effects and it we take for granted very


00:25:44.399 --> 00:25:46.470
very much that our perception is


00:25:46.480 --> 00:25:48.990
actually what is out there yeah and this


00:25:49.000 --> 00:25:51.909
was brought home to me I went to driving


00:25:51.919 --> 00:25:53.950
range with one of my PhD students on I


00:25:53.960 --> 00:25:55.590
don't play golf and I'm particularly bad


00:25:55.600 --> 00:25:57.710
at it but there's always this thing


00:25:57.720 --> 00:25:59.470
about what you perceive and how much of


00:25:59.480 --> 00:26:01.190
the area of your vision that you're


00:26:01.200 --> 00:26:02.830
actually actively updating and how much


00:26:02.840 --> 00:26:04.710
of it is just autogenerated by your


00:26:04.720 --> 00:26:07.149
brain based on Old information and you


00:26:07.159 --> 00:26:09.470
forget about that but we actually are


00:26:09.480 --> 00:26:11.070
like our eyes are rasling across and we


00:26:11.080 --> 00:26:13.750
only see a tiny little bit of our vision


00:26:13.760 --> 00:26:15.230
are we seeing true updates and I've


00:26:15.240 --> 00:26:17.350
never really seen that demonstrated


00:26:17.360 --> 00:26:18.669
until I was at the driving range because


00:26:18.679 --> 00:26:20.870
if I hit a golf ball and I often hit


00:26:20.880 --> 00:26:22.310
them very badly but they go up in the


00:26:22.320 --> 00:26:24.549
air somewhere and I can stand there and


00:26:24.559 --> 00:26:26.830
watch where it dos and it's easy and you


00:26:26.840 --> 00:26:28.870
can follow it all the way the minute you


00:26:28.880 --> 00:26:31.149
look away and look back you cannot find


00:26:31.159 --> 00:26:33.830
the ball exactly it's astonishing and


00:26:33.840 --> 00:26:35.669
you think when you're just looking at it


00:26:35.679 --> 00:26:37.950
it's really obvious there's a ball there


00:26:37.960 --> 00:26:39.750
it's yellow or white against the Blue


00:26:39.760 --> 00:26:42.230
Sky can't get more obvious Look Away


00:26:42.240 --> 00:26:43.789
totally lost it even if you know where


00:26:43.799 --> 00:26:46.870
it was and that's all down to how our


00:26:46.880 --> 00:26:48.510
brain is processing the data we're


00:26:48.520 --> 00:26:50.669
getting the ball's still there the ball


00:26:50.679 --> 00:26:52.990
hasn't miraculously disappeared and so


00:26:53.000 --> 00:26:55.110
all these kind of questions I find it


00:26:55.120 --> 00:26:56.870
really fascinating that boundary between


00:26:56.880 --> 00:26:58.830
the perception and the reality


00:26:58.840 --> 00:27:01.590
how much of what we observe is of our


00:27:01.600 --> 00:27:03.630
own generation essentially yeah it


00:27:03.640 --> 00:27:05.510
reminds me of that famous gorilla


00:27:05.520 --> 00:27:08.750
experiment you aware of that one yeah um


00:27:08.760 --> 00:27:12.310
that that is a very great it's a great


00:27:12.320 --> 00:27:15.630
example of of what you think you see and


00:27:15.640 --> 00:27:18.950
what's really there and uh I won't try


00:27:18.960 --> 00:27:20.789
and spoil it for anybody you can see it


00:27:20.799 --> 00:27:22.870
on


00:27:22.880 --> 00:27:24.710
YouTube they do that in a lot of


00:27:24.720 --> 00:27:26.269
training for things like police officers


00:27:26.279 --> 00:27:28.669
and stuff to talk about the fact people


00:27:28.679 --> 00:27:29.909
who think they've witnessed something


00:27:29.919 --> 00:27:32.950
are inherently unreliable yeah and it's


00:27:32.960 --> 00:27:35.750
also what makes it very feasible for


00:27:35.760 --> 00:27:38.789
magicians and concerts and tricksters to


00:27:38.799 --> 00:27:41.310
trick you by taking your brain off


00:27:41.320 --> 00:27:42.630
somewhere else you know the whole slight


00:27:42.640 --> 00:27:44.630
of hand thing is all born of this same


00:27:44.640 --> 00:27:47.430
thing yeah yeah it is it's really


00:27:47.440 --> 00:27:49.110
remarkable I could talk about this stuff


00:27:49.120 --> 00:27:51.909
forever I really find it fascinating but


00:27:51.919 --> 00:27:53.990
uh yeah lovely question David and I hope


00:27:54.000 --> 00:27:56.990
that it um covered you adequately as we


00:27:57.000 --> 00:27:59.590
strive to do here on B nuts but no black


00:27:59.600 --> 00:28:06.350
hole can't make light travel faster than


00:28:06.360 --> 00:28:09.630
light Space Nuts our final question


00:28:09.640 --> 00:28:12.950
comes from a regular Cendera from um the


00:28:12.960 --> 00:28:15.509
United Kingdom hello Duncan from


00:28:15.519 --> 00:28:17.990
Waymouth in the UK here


00:28:18.000 --> 00:28:21.909
again um just wondering is it possible


00:28:21.919 --> 00:28:26.230
to have an exoplanet that is entirely


00:28:26.240 --> 00:28:29.470
liquid so it could just be like a global


00:28:29.480 --> 00:28:34.269
ocean but with no solid core just liquid


00:28:34.279 --> 00:28:35.630
all the way


00:28:35.640 --> 00:28:38.350
through if it's not possible and it has


00:28:38.360 --> 00:28:39.870
to have a solid


00:28:39.880 --> 00:28:43.350
core why is that and


00:28:43.360 --> 00:28:47.509
also how small could that solid core be


00:28:47.519 --> 00:28:51.230
could it be something the size of say


00:28:51.240 --> 00:28:55.350
Everest or could it be even smaller or


00:28:55.360 --> 00:28:58.789
does it have to be something bigger


00:28:58.799 --> 00:29:01.029
maybe the size of the moon I I don't


00:29:01.039 --> 00:29:04.149
know um what are your thoughts on that


00:29:04.159 --> 00:29:06.630
and opinions um do you have any actual


00:29:06.640 --> 00:29:09.950
answers does anyone know um just


00:29:09.960 --> 00:29:12.990
wondering perhaps you could give us some


00:29:13.000 --> 00:29:16.310
answers with regards to that okay thank


00:29:16.320 --> 00:29:20.269
you very much uh keep up the good work


00:29:20.279 --> 00:29:24.110
um and uh well until next time thank you


00:29:24.120 --> 00:29:25.830
Duncan I love this question because


00:29:25.840 --> 00:29:27.870
these are the sorts of things I wonder


00:29:27.880 --> 00:29:30.190
yeah uh and and look we've got examples


00:29:30.200 --> 00:29:32.710
of ice worlds in our solar system they


00:29:32.720 --> 00:29:35.710
are ice moons they have a solid surface


00:29:35.720 --> 00:29:37.750
and and it's thought that they probably


00:29:37.760 --> 00:29:40.990
have a solid core but in between oceans


00:29:41.000 --> 00:29:43.350
but he's talking about an exoplanet that


00:29:43.360 --> 00:29:46.990
is pure liquid just a Big Blob of water


00:29:47.000 --> 00:29:50.750
yes it's a fabulous question and again


00:29:50.760 --> 00:29:52.350
this can have a short answer in the long


00:29:52.360 --> 00:29:54.990
answer the short answer is essentially


00:29:55.000 --> 00:29:57.029
no but it's not for the reason you're


00:29:57.039 --> 00:29:58.750
thinking of it's not to do with the core


00:29:58.760 --> 00:30:00.509
it's the fact that nothing can be a


00:30:00.519 --> 00:30:02.029
liquid that I'm aware of in the vacuum


00:30:02.039 --> 00:30:04.870
of space so on the surface of the liquid


00:30:04.880 --> 00:30:06.230
you will get evaporation and you would


00:30:06.240 --> 00:30:07.870
end up with an atmosphere so you'd end


00:30:07.880 --> 00:30:10.149
up with a gasier shroud around it


00:30:10.159 --> 00:30:11.630
doesn't need to be much atmosphere so


00:30:11.640 --> 00:30:13.110
technically it couldn't be entirely


00:30:13.120 --> 00:30:14.630
liquid because it would need to be gas


00:30:14.640 --> 00:30:16.870
around it for there to be sufficient


00:30:16.880 --> 00:30:18.950
pressure that the material on the


00:30:18.960 --> 00:30:21.990
surface can remain liquid you could


00:30:22.000 --> 00:30:23.389
create something of course but you'd


00:30:23.399 --> 00:30:25.470
need it like a bubble around it glass


00:30:25.480 --> 00:30:28.070
shell or whatever yeah the other reason


00:30:28.080 --> 00:30:30.590
that in a physical sense it would be


00:30:30.600 --> 00:30:33.950
very unlikely to have this is that the


00:30:33.960 --> 00:30:35.950
things that you form are made of


00:30:35.960 --> 00:30:38.789
everything that's around um rocky


00:30:38.799 --> 00:30:40.990
planets don't capture the hydrogen and


00:30:41.000 --> 00:30:42.870
helium their escape velocity is too high


00:30:42.880 --> 00:30:45.029
so the gravity is too weak but when


00:30:45.039 --> 00:30:46.389
you're forming something you're building


00:30:46.399 --> 00:30:47.710
a planet you're building it of


00:30:47.720 --> 00:30:49.990
everything that is around so that will


00:30:50.000 --> 00:30:51.430
include a lot of water if you're


00:30:51.440 --> 00:30:52.830
somewhere where the temperature's low


00:30:52.840 --> 00:30:54.630
enough for water to become an ice and to


00:30:54.640 --> 00:30:56.830
be a solid but it'll also include iron


00:30:56.840 --> 00:30:59.990
and nickel and dust and all the other


00:31:00.000 --> 00:31:02.310
stuff and you're not going to have a


00:31:02.320 --> 00:31:04.110
situation where everything you form a


00:31:04.120 --> 00:31:07.470
planet from would all be liquid at the


00:31:07.480 --> 00:31:10.070
same conditions so you'd always end up


00:31:10.080 --> 00:31:12.389
with some stuff sinking to the middle of


00:31:12.399 --> 00:31:14.870
solids what you could imagine though is


00:31:14.880 --> 00:31:17.950
you could have a idealized situation


00:31:17.960 --> 00:31:19.750
let's say you could quarantine an area


00:31:19.760 --> 00:31:22.149
of space off and you could form


00:31:22.159 --> 00:31:25.669
something Planet Mass out of absolutely


00:31:25.679 --> 00:31:28.029
perfectly pure water ice so nothing else


00:31:28.039 --> 00:31:30.909
but hydrogen and oxygen bound together


00:31:30.919 --> 00:31:33.509
in that scenario I could imagine you


00:31:33.519 --> 00:31:36.110
having a planet that is almost entirely


00:31:36.120 --> 00:31:38.669
liquid except for the atmosphere which


00:31:38.679 --> 00:31:40.830
would be water vapor and would probably


00:31:40.840 --> 00:31:42.350
then quickly become an oxygen-rich


00:31:42.360 --> 00:31:44.710
atmosphere because once you've got water


00:31:44.720 --> 00:31:47.110
vapor exposed to UV it gets dissociated


00:31:47.120 --> 00:31:48.950
into hydrogen and oxygen blah blah blah


00:31:48.960 --> 00:31:52.389
all stive happens there you would then


00:31:52.399 --> 00:31:55.870
have a situation where depending on the


00:31:55.880 --> 00:31:57.950
mass of the object


00:31:57.960 --> 00:31:59.789
you could have a an object liquid all


00:31:59.799 --> 00:32:02.029
the way through if the object is too low


00:32:02.039 --> 00:32:05.669
a mass you'd gradually lose it because


00:32:05.679 --> 00:32:07.230
if it's of a low enough mass and it's


00:32:07.240 --> 00:32:09.350
going around the star the stuff that's


00:32:09.360 --> 00:32:11.990
boiling off for a gas will then be


00:32:12.000 --> 00:32:13.629
moving fast enough to escape so the


00:32:13.639 --> 00:32:14.909
atmosphere will be stripped and the


00:32:14.919 --> 00:32:16.430
thing will essentially boil away like if


00:32:16.440 --> 00:32:18.950
you leave a pan on the hob I would


00:32:18.960 --> 00:32:21.950
imagine that there is also a range of


00:32:21.960 --> 00:32:23.870
sizes and masses where the pressure in


00:32:23.880 --> 00:32:26.310
the center gets so high that the water


00:32:26.320 --> 00:32:27.950
becomes ice again even at High


00:32:27.960 --> 00:32:30.070
temperature and we see this with Uranus


00:32:30.080 --> 00:32:32.190
and netrun there is certainly Water Ice


00:32:32.200 --> 00:32:34.509
in the interior of those but it's a


00:32:34.519 --> 00:32:36.509
different phase of water Riz to that


00:32:36.519 --> 00:32:37.830
we're used to I I never really


00:32:37.840 --> 00:32:39.149
understood this but there is an


00:32:39.159 --> 00:32:41.710
incredibly gifted Australian researcher


00:32:41.720 --> 00:32:44.909
called Helen Menard kley who last time I


00:32:44.919 --> 00:32:46.509
saw I've not seen her for a few years


00:32:46.519 --> 00:32:49.070
but she used to work down at ano at um


00:32:49.080 --> 00:32:51.669
in Northern Sydney using devices like


00:32:51.679 --> 00:32:53.830
wbat doing X-ray defraction and stuff


00:32:53.840 --> 00:32:56.509
like this and she discovered several new


00:32:56.519 --> 00:32:58.789
types of Water Ice she was looking at


00:32:58.799 --> 00:33:01.389
what happens to water at temperatures


00:33:01.399 --> 00:33:03.230
and pressures very different to room


00:33:03.240 --> 00:33:05.549
temperature and that can be really cold


00:33:05.559 --> 00:33:07.590
conditions lack on the icy M of Jupiter


00:33:07.600 --> 00:33:09.549
or it can be really high pressures or


00:33:09.559 --> 00:33:11.430
birth and so it's fairly well


00:33:11.440 --> 00:33:13.350
established that if you increase the


00:33:13.360 --> 00:33:16.230
pressure water ice will remain solid at


00:33:16.240 --> 00:33:17.669
higher


00:33:17.679 --> 00:33:20.149
temperatures that this boiling at 100


00:33:20.159 --> 00:33:22.269
and freezing at zero is a function of


00:33:22.279 --> 00:33:24.310
the current atmosphere pressure we have


00:33:24.320 --> 00:33:25.549
on Earth and you change that and it


00:33:25.559 --> 00:33:28.070
changes yeah incidentally that that's


00:33:28.080 --> 00:33:30.110
why if you're a bit of a tea fish inard


00:33:30.120 --> 00:33:31.830
you cannot get a good cup of tea at high


00:33:31.840 --> 00:33:34.110
altitude because water boils at a low


00:33:34.120 --> 00:33:35.789
enough temperature that it makes him a


00:33:35.799 --> 00:33:38.029
cup of tea you know people who went into


00:33:38.039 --> 00:33:39.549
the Himalayas grumbling about how


00:33:39.559 --> 00:33:41.870
terrible the tea was and you're at high


00:33:41.880 --> 00:33:43.389
enough altitude that the boiling point


00:33:43.399 --> 00:33:47.110
of water is reduced enough that um and


00:33:47.120 --> 00:33:48.629
for people listening in America who


00:33:48.639 --> 00:33:50.430
aren't familiar with this people


00:33:50.440 --> 00:33:51.909
particularly from the UK are very


00:33:51.919 --> 00:33:53.430
obsessive about their tea but to make


00:33:53.440 --> 00:33:54.909
tea you need the water to be on a


00:33:54.919 --> 00:33:58.669
rolling boil at 100° C for for many


00:33:58.679 --> 00:34:00.549
kinds of black teas green tea and white


00:34:00.559 --> 00:34:02.750
tea it's a colder temperature but when


00:34:02.760 --> 00:34:05.990
you make tea with lukewarm water that is


00:34:06.000 --> 00:34:07.629
wrong that just doesn't work and you get


00:34:07.639 --> 00:34:09.430
a very different behavior and it's to do


00:34:09.440 --> 00:34:11.389
with the chemistry of what goes


00:34:11.399 --> 00:34:17.069
on yeah that's fascinating yeah into


00:34:17.079 --> 00:34:19.190
this which would lead to if we ever


00:34:19.200 --> 00:34:21.349
found a planet that was pure water and


00:34:21.359 --> 00:34:23.589
was Liquid all the way through that to


00:34:23.599 --> 00:34:25.349
me would be evidence of the Builders of


00:34:25.359 --> 00:34:27.430
magra from double saddens you know would


00:34:27.440 --> 00:34:29.310
be evidence that this was a constructed


00:34:29.320 --> 00:34:30.869
entity rather than something that form


00:34:30.879 --> 00:34:33.149
naturally F contamination is the


00:34:33.159 --> 00:34:34.389
simplest way of saying you wouldn't get


00:34:34.399 --> 00:34:36.430
a purely Liquid Planet you can get a


00:34:36.440 --> 00:34:38.270
planet that is more liquid than anything


00:34:38.280 --> 00:34:40.510
else and we have suspicions that there


00:34:40.520 --> 00:34:43.829
are these hean World desertion planets


00:34:43.839 --> 00:34:45.710
and the reasoning there is that water is


00:34:45.720 --> 00:34:46.909
actually one of the most common things


00:34:46.919 --> 00:34:48.750
in the universe you've got the most


00:34:48.760 --> 00:34:50.230
common atom with hydrogen you've got the


00:34:50.240 --> 00:34:51.869
third most common atom with oxygen you


00:34:51.879 --> 00:34:53.950
put them together you get water ice or


00:34:53.960 --> 00:34:56.790
liquid water or water vapor so you can


00:34:56.800 --> 00:34:58.950
imagine planets have more water than


00:34:58.960 --> 00:35:01.630
anything else that are huge oceans with


00:35:01.640 --> 00:35:04.510
a core underneath them that are ice and


00:35:04.520 --> 00:35:06.470
then liquid then ice again like we see


00:35:06.480 --> 00:35:08.670
with out mes but getting something that


00:35:08.680 --> 00:35:10.670
is liquid from the surface to the core


00:35:10.680 --> 00:35:13.069
has those problems one of contamination


00:35:13.079 --> 00:35:14.589
and one of you would need an atmosphere


00:35:14.599 --> 00:35:16.390
to have the pressure to remain


00:35:16.400 --> 00:35:18.829
liquid fascinating yeah love that


00:35:18.839 --> 00:35:20.710
question Duncan uh so the answer is


00:35:20.720 --> 00:35:24.230
probably no but um not far off in some


00:35:24.240 --> 00:35:26.470
respects but uh yeah it might take a


00:35:26.480 --> 00:35:29.470
mega structure of some kind to create a


00:35:29.480 --> 00:35:32.510
water world although um Kevin cner did


00:35:32.520 --> 00:35:35.510
find one yeah appar the cost of going


00:35:35.520 --> 00:35:37.950
there to film the film we outrageous so


00:35:37.960 --> 00:35:39.750
yes yes they're trying to get it all


00:35:39.760 --> 00:35:41.910
back with a theme park I think but um


00:35:41.920 --> 00:35:44.230
yes thank you Duncan always good to hear


00:35:44.240 --> 00:35:45.550
from you you've always got some great


00:35:45.560 --> 00:35:47.589
ideas uh and if you would like to send


00:35:47.599 --> 00:35:50.030
us some questions please do via our


00:35:50.040 --> 00:35:52.510
website Space Nuts podcast.com SPAC


00:35:52.520 --> 00:35:54.390
nuts. and have a look around while


00:35:54.400 --> 00:35:55.630
you're there check out the shop check


00:35:55.640 --> 00:35:58.349
out our all the other things uh


00:35:58.359 --> 00:36:00.069
and don't forget to click the AMA thing


00:36:00.079 --> 00:36:01.990
at the top which is where you send your


00:36:02.000 --> 00:36:05.069
questions text or audio versions um


00:36:05.079 --> 00:36:07.109
thank you johy that was great fun it's a


00:36:07.119 --> 00:36:08.470
pleasure it's always good to chat thank


00:36:08.480 --> 00:36:10.670
you for having me oh no my pleasure


00:36:10.680 --> 00:36:12.230
we'll catch up with you next time


00:36:12.240 --> 00:36:13.430
Professor jonty Horner from the


00:36:13.440 --> 00:36:15.950
University of Southern Queensland uh


00:36:15.960 --> 00:36:18.349
Hugh couldn't be with us today I don't


00:36:18.359 --> 00:36:20.230
know what he's been up to but I do know


00:36:20.240 --> 00:36:22.230
about today apparently he was using a


00:36:22.240 --> 00:36:24.910
telescope to try and see his own


00:36:24.920 --> 00:36:26.910
reflection he's still going he's been


00:36:26.920 --> 00:36:29.829
doing it for days apparently uh and from


00:36:29.839 --> 00:36:31.349
me Andrew Dunley thanks for your company


00:36:31.359 --> 00:36:32.630
catch you on the very next episode of


00:36:32.640 --> 00:36:35.910
Space Nuts bye-bye Space Nuts you been


00:36:35.920 --> 00:36:38.750
listening to the Space Nuts


00:36:38.760 --> 00:36:41.829
podcast available at Apple podcasts


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00:36:49.800 --> 00:36:52.230
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