00:00:00 --> 00:00:01 hi there thanks for joining us on
00:00:01 --> 00:00:03 another episode of Space Nuts Andrew
00:00:03 --> 00:00:05 Dunley here and it's good to have you
00:00:05 --> 00:00:08 all company coming up on this episode
00:00:08 --> 00:00:10 we're going to be looking at snowball
00:00:10 --> 00:00:13 Earth there was a time where it was just
00:00:13 --> 00:00:16 a frozen sphere of nothingness for well
00:00:17 --> 00:00:19 billions of years uh now they have a new
00:00:19 --> 00:00:22 theory about that and it's no Irish
00:00:22 --> 00:00:25 joke there's a clue in there uh the
00:00:25 --> 00:00:27 dinosaur asteroids origin has been
00:00:28 --> 00:00:30 revealed yep the thing that started
00:00:30 --> 00:00:33 the getting rid of them all across the
00:00:33 --> 00:00:36 planet we know where it came from and uh
00:00:36 --> 00:00:38 the so-called crisis in cosmology might
00:00:38 --> 00:00:40 not be a crisis at all we're talking
00:00:40 --> 00:00:42 about the Hubble tension we'll talk
00:00:42 --> 00:00:45 about all of that on this episode of
00:00:45 --> 00:00:48 Space Nuts 15 seconds guidance is
00:00:48 --> 00:00:53 internal 10 9 ignition sequence start
00:00:53 --> 00:00:59 Space Nuts 5 4 3 2 1 2 3 4 5 5 4 3 2 1
00:00:59 --> 00:01:00 space
00:01:00 --> 00:01:04 as report feels good and to help us
00:01:04 --> 00:01:08 unravel all of that decipher it and use
00:01:08 --> 00:01:09 his code book to figure a few more
00:01:09 --> 00:01:11 things out is Professor Fred Watson
00:01:12 --> 00:01:14 astronomer at large hello Fred hello
00:01:14 --> 00:01:16 Andrew keep up the good work there it's
00:01:16 --> 00:01:18 going very
00:01:18 --> 00:01:21 well uh good to see you uh I I just I
00:01:21 --> 00:01:23 thought I'd sort of start out a left
00:01:23 --> 00:01:27 field because um I I spotted a story uh
00:01:27 --> 00:01:31 only today actually uh which dovetails
00:01:31 --> 00:01:32 with something we talked about some time
00:01:32 --> 00:01:34 ago and and that was the work that's
00:01:35 --> 00:01:38 being done to perfect uh engine
00:01:38 --> 00:01:41 technology to achieve greater speeds uh
00:01:41 --> 00:01:44 for Interstellar travel in years to come
00:01:44 --> 00:01:46 or maybe not Interstellar but
00:01:46 --> 00:01:48 interplanetary perhaps and we know NASA
00:01:49 --> 00:01:51 is is working on this kind of technology
00:01:51 --> 00:01:54 to to create uh
00:01:54 --> 00:01:58 really fast and high performance engines
00:01:58 --> 00:02:00 they're working with I think it's enal
00:02:00 --> 00:02:02 electric to achieve that uh they may
00:02:02 --> 00:02:04 have been gazumped fret have you heard
00:02:04 --> 00:02:05 about
00:02:05 --> 00:02:07 this uh
00:02:07 --> 00:02:11 no uh the Chinese the Chinese claim to
00:02:11 --> 00:02:15 have developed a a new engine that can
00:02:15 --> 00:02:18 achieve a speed of
00:02:18 --> 00:02:23 12 mil hour or 19 km an hour and
00:02:23 --> 00:02:25 uh the aircraft can reach an altitude of
00:02:25 --> 00:02:28 30 kilm now you compare that to the
00:02:28 --> 00:02:34 Concord uh it's uh Mac 16 versus MAC 2
00:02:34 --> 00:02:37 uh which is an extraordinary claim now
00:02:37 --> 00:02:39 apparently they've released a paper
00:02:39 --> 00:02:41 which has been peer-reviewed from what I
00:02:41 --> 00:02:44 understand um and it's not April the 1st
00:02:44 --> 00:02:47 I'm confident of that so they reckon
00:02:47 --> 00:02:50 that they've they've made this leap in
00:02:50 --> 00:02:55 technology to develop a Max 16 engine
00:02:55 --> 00:02:57 and just think of this Fred you'd be
00:02:57 --> 00:03:00 able to fly from Sydney to New York talk
00:03:00 --> 00:03:05 in 50 minutes yes that's what 50
00:03:05 --> 00:03:08 minutes uh that's extraordinary if it if
00:03:08 --> 00:03:10 it's real and I I don't see why it
00:03:10 --> 00:03:12 wouldn't be but you never know with
00:03:12 --> 00:03:15 these things but um apparently according
00:03:15 --> 00:03:17 to the paper the engine operates in two
00:03:17 --> 00:03:18 modes there's a continuous rotating
00:03:18 --> 00:03:20 detonation engine which is a scary thing
00:03:21 --> 00:03:22 in itself by the sound of it which will
00:03:22 --> 00:03:25 get it to Mark 7even and uh you know the
00:03:25 --> 00:03:27 air and the fuel create a rotating shock
00:03:27 --> 00:03:30 wave with continuous thrust and then a
00:03:30 --> 00:03:34 straight line oblique detonation engine
00:03:34 --> 00:03:37 which fires above Mark 7 and pushes it
00:03:37 --> 00:03:38 all the way to Mark
00:03:38 --> 00:03:43 16 um it sounds amazing sounds amazing
00:03:43 --> 00:03:46 uh how far short they are of getting
00:03:46 --> 00:03:48 this into production I don't know but um
00:03:48 --> 00:03:50 it certainly sounds like it's in
00:03:50 --> 00:03:53 development that would be amazing to to
00:03:53 --> 00:03:55 be able to achieve those kinds of speeds
00:03:56 --> 00:03:58 uh it would revolutionize travel around
00:03:58 --> 00:03:58 the
00:03:58 --> 00:04:01 world but it's been done
00:04:01 --> 00:04:05 already by yeah the British have been
00:04:05 --> 00:04:09 working on this for decades now with
00:04:09 --> 00:04:12 their air it's an air breathing um it's
00:04:12 --> 00:04:16 a Hybrid engine that breathes Air at it
00:04:16 --> 00:04:18 at at low altitudes and turns into a
00:04:18 --> 00:04:20 rocket motor when you get above the
00:04:20 --> 00:04:22 Earth's atmosphere yeah I think I did
00:04:22 --> 00:04:23 hear about that I didn't know i' got to
00:04:23 --> 00:04:26 those sort of speeds yeah well it can
00:04:26 --> 00:04:28 it's capable of entering orbit so it can
00:04:28 --> 00:04:31 get up to you know 20 6 km an hour
00:04:31 --> 00:04:33 but but but it's then acting as a rocket
00:04:33 --> 00:04:37 motor so it's um the project was called
00:04:37 --> 00:04:39 well hotol was the style of thing
00:04:39 --> 00:04:42 horizontal takeoff and Landing um so
00:04:42 --> 00:04:44 it's flies like a plane takes off like a
00:04:44 --> 00:04:47 plane with the air burning jet engines
00:04:47 --> 00:04:50 just gradually accelerates uh clicks
00:04:50 --> 00:04:55 over into being a um a rocket motor uh
00:04:55 --> 00:04:57 when the atmosphere gets too rarified
00:04:57 --> 00:05:00 and then sends you up to orbit uh but
00:05:00 --> 00:05:02 the as I remember right I think it's
00:05:02 --> 00:05:03 called the saber the engine if I
00:05:03 --> 00:05:06 remember rightly it's saber but the big
00:05:06 --> 00:05:11 problem was um keeping the air cool and
00:05:11 --> 00:05:14 there was some the main breakthrough was
00:05:14 --> 00:05:16 apparently a heat exchanger that could
00:05:16 --> 00:05:19 bring the temperature of the air uh down
00:05:19 --> 00:05:23 from 700° cius or something to liquid
00:05:23 --> 00:05:25 nitrogen temperatures in something like
00:05:25 --> 00:05:27 a thousandth of a second as it passes
00:05:27 --> 00:05:30 through the engine um and was a big
00:05:30 --> 00:05:31 breakthrough now we've I think we've
00:05:31 --> 00:05:33 spoken about it before a long long time
00:05:33 --> 00:05:34 ago because there hasn't really been
00:05:34 --> 00:05:36 much news it was being supported by the
00:05:36 --> 00:05:38 British government I don't know whether
00:05:38 --> 00:05:41 that support has has now dwindled um
00:05:42 --> 00:05:43 because it would be you know the idea
00:05:43 --> 00:05:45 about this was economics it was to be
00:05:45 --> 00:05:47 able to have the same Spa spacecraft
00:05:47 --> 00:05:48 that will take you up there and bring
00:05:48 --> 00:05:51 you back and was completely reusable and
00:05:51 --> 00:05:54 to some extent I think um uh Elon musk's
00:05:54 --> 00:05:57 basx and their Falcon 9es have kind of
00:05:57 --> 00:05:58 cornered the market on that because
00:05:58 --> 00:06:00 they've they've now got reusable
00:06:00 --> 00:06:02 spacecraft which are routinely being
00:06:02 --> 00:06:05 used every day uh almost so maybe
00:06:05 --> 00:06:08 there's no space for it but yeah
00:06:08 --> 00:06:09 extraordinary technology and and I'm
00:06:10 --> 00:06:12 sure the Chinese technology is is above
00:06:12 --> 00:06:14 board what you've just been describing
00:06:14 --> 00:06:15 yeah it's from the Beijing Power
00:06:15 --> 00:06:17 Machinery Institute and theyve published
00:06:17 --> 00:06:20 their paper in the Chinese Journal of
00:06:20 --> 00:06:22 propulsion technology I can I can see a
00:06:22 --> 00:06:24 problem with it though let's say they do
00:06:24 --> 00:06:26 create an airliner that can do that trip
00:06:27 --> 00:06:29 in 50 minutes from New York to Sydney
00:06:29 --> 00:06:30 for example
00:06:30 --> 00:06:31 you'd leave at 7:00 in the morning in
00:06:31 --> 00:06:34 New York you'd arrive at 11:00 p.m. 50
00:06:34 --> 00:06:38 minutes later in Sydney so you'd get up
00:06:38 --> 00:06:40 and get on the plane then get to Sydney
00:06:40 --> 00:06:43 and then have to go to bed right away
00:06:43 --> 00:06:45 yes that's right that's the issue it's
00:06:46 --> 00:06:48 always the issue it would make jet lag
00:06:48 --> 00:06:51 all the more worse but you know I think
00:06:51 --> 00:06:54 I'd put up with that rather than all
00:06:54 --> 00:06:58 those 20 hours 20 hour flight yeah I've
00:06:58 --> 00:06:59 got one of those coming up very soon
00:06:59 --> 00:07:03 actually you do that's right yeah be
00:07:03 --> 00:07:04 yeah to watch this space story but I
00:07:04 --> 00:07:06 just find it fascinating these these
00:07:06 --> 00:07:08 kinds of um leaps in
00:07:08 --> 00:07:11 technology let's move on uh a new theory
00:07:11 --> 00:07:14 about snowball Earth Fred I said there's
00:07:15 --> 00:07:16 um there's no Irish joke attached to
00:07:16 --> 00:07:19 this and there was a good reason I said
00:07:19 --> 00:07:21 that which I'm probably going to
00:07:21 --> 00:07:24 sidestep completely uh it's about rocks
00:07:24 --> 00:07:26 in Scotland and in
00:07:26 --> 00:07:28 Australia I thought it was I thought
00:07:28 --> 00:07:29 they said there was some of these rocks
00:07:29 --> 00:07:31 in Ireland as well yeah I think I think
00:07:31 --> 00:07:34 there are I think that's right think we
00:07:34 --> 00:07:36 that's the loose connection I made
00:07:36 --> 00:07:40 with um it it also includes rocks in
00:07:40 --> 00:07:44 Namibia uh and North America uh as well
00:07:44 --> 00:07:46 as uh Scotland uh you're probably right
00:07:46 --> 00:07:49 Ireland in Ireland because um the it's
00:07:49 --> 00:07:50 the west of Scotland where these where
00:07:50 --> 00:07:53 these rocks are that have recently been
00:07:53 --> 00:07:56 analyzed uh and I mean it's an
00:07:56 --> 00:07:57 interesting story I've often wondered
00:07:57 --> 00:07:59 about snowball Earth and never really
00:07:59 --> 00:08:02 looked at at the details of it so it's a
00:08:02 --> 00:08:06 period of about 60 million years ago oh
00:08:06 --> 00:08:10 sorry 60 million years long but it was a
00:08:10 --> 00:08:13 long time ago it began 700 million years
00:08:13 --> 00:08:16 ago uh in fact probably more like 720
00:08:16 --> 00:08:19 million years ago and lasted until about
00:08:19 --> 00:08:22 635 million years ago and it's called
00:08:22 --> 00:08:25 the cryogenian cryogenian geological
00:08:25 --> 00:08:27 period and anything with cryo in the
00:08:27 --> 00:08:30 front of it means it's frozen solid yeah
00:08:30 --> 00:08:33 uh and so um and so I thought well how
00:08:33 --> 00:08:37 do we know this and the way we know
00:08:37 --> 00:08:40 it and the way we know that I glacial
00:08:40 --> 00:08:44 ice covered the whole planet is because
00:08:44 --> 00:08:47 you can see in the geology the effects
00:08:47 --> 00:08:48 of
00:08:48 --> 00:08:51 glaciation uh everywhere it's not just
00:08:51 --> 00:08:54 you know I grew up in a country where
00:08:54 --> 00:08:56 10 years ago the whole of the
00:08:56 --> 00:08:58 northern part of Britain was under ice
00:08:58 --> 00:09:00 and so my all my school lessons were
00:09:00 --> 00:09:03 about glacial features uh in the north
00:09:03 --> 00:09:07 of England and so so you could tell from
00:09:07 --> 00:09:10 rocks uh whether something has been
00:09:10 --> 00:09:12 glaciated and that's how we know
00:09:12 --> 00:09:15 everywhere there is this layer of rock
00:09:15 --> 00:09:17 uh corresponding to looking back you
00:09:17 --> 00:09:21 know six six 700 million years where you
00:09:21 --> 00:09:23 see the evidence of glaciation um and so
00:09:24 --> 00:09:27 the interpretation of that is that you
00:09:27 --> 00:09:30 uh you had an Ice Age that would was the
00:09:30 --> 00:09:32 if I put it the the grandfather of all
00:09:32 --> 00:09:36 ice ages uh the whole planet was frozen
00:09:36 --> 00:09:39 uh and so the the new research concerns
00:09:39 --> 00:09:42 uh evidence from rocks in Scotland uh
00:09:42 --> 00:09:46 and what's remarkable is that uh the
00:09:46 --> 00:09:49 sort of gla the glacial evidence there
00:09:49 --> 00:09:52 shows up really clearly uh for some
00:09:52 --> 00:09:55 reason that has been preserved very well
00:09:55 --> 00:09:57 uh there you know underneath the
00:09:57 --> 00:09:58 sediments that were dropped on top of
00:09:59 --> 00:10:03 onp top of it um later on but um the
00:10:03 --> 00:10:07 bottom line about the uh the reason why
00:10:07 --> 00:10:11 we got this ice age is a is a question
00:10:11 --> 00:10:12 um I'm not sure that in the article I
00:10:13 --> 00:10:15 sent you it's it goes into detail about
00:10:15 --> 00:10:18 it uh but the thinking is that we were
00:10:18 --> 00:10:23 seeing a period when um or before this
00:10:23 --> 00:10:25 period uh we were seeing a
00:10:25 --> 00:10:31 time when uh volcanic rocks were being
00:10:31 --> 00:10:33 were being uh eroded they were being
00:10:33 --> 00:10:36 weathered very rapidly and apparently
00:10:36 --> 00:10:38 these were particularly in Canada uh
00:10:38 --> 00:10:40 these volcanic rocks I'm Looking Back
00:10:40 --> 00:10:44 Now perhaps 720 million years um they
00:10:44 --> 00:10:48 were eroded by weathering and that
00:10:48 --> 00:10:51 process sucks carbon dioxide out of the
00:10:51 --> 00:10:54 atmosphere uh and so um what you're
00:10:54 --> 00:10:57 seeing is a situation where the
00:10:57 --> 00:11:01 atmospheric carbon dioxide is lower uh
00:11:01 --> 00:11:04 than normal and in fact uh it is
00:11:04 --> 00:11:07 probably was probably about half uh what
00:11:07 --> 00:11:10 today's level is today's level's in the
00:11:10 --> 00:11:12 region of 400 parts per million of
00:11:12 --> 00:11:14 carbon dioxide in the atmosphere and
00:11:14 --> 00:11:16 that's enough to blanket our planet and
00:11:16 --> 00:11:18 keep the temperature stable uh unless
00:11:18 --> 00:11:20 you put more in in which case the
00:11:20 --> 00:11:22 temperature goes up as you know uh but
00:11:22 --> 00:11:25 uh if you drop too far down uh then you
00:11:26 --> 00:11:29 get an ice ball um they estimate the
00:11:29 --> 00:11:33 atmospheric carbon dioxide levels uh
00:11:33 --> 00:11:35 back in the cryogenic period or
00:11:35 --> 00:11:39 cryogenian period uh they estimate they
00:11:39 --> 00:11:41 were below 200 parts per million and
00:11:41 --> 00:11:43 what that does is lets the heat just
00:11:43 --> 00:11:46 radiate out into the uh into space and
00:11:46 --> 00:11:48 you lose heat the Earth's surface
00:11:48 --> 00:11:51 becomes very cold uh and uh basically
00:11:51 --> 00:11:53 you get the snowball Earth you get an
00:11:53 --> 00:11:57 earth that is covered with ice um the
00:11:57 --> 00:11:58 it's the same sort of thing that we
00:11:58 --> 00:11:59 think happened of Mars as very low
00:12:00 --> 00:12:02 carbon dioxide content and that's why we
00:12:02 --> 00:12:04 think it got cold and dry rather than
00:12:04 --> 00:12:06 warm and white as it once
00:12:06 --> 00:12:08 was the other there's a lot of moving
00:12:08 --> 00:12:10 parts to this story but uh one of the
00:12:10 --> 00:12:14 things I found most interesting was if
00:12:14 --> 00:12:18 this Mega freeze hadn't happened Life as
00:12:18 --> 00:12:21 we know it may not have developed
00:12:21 --> 00:12:23 because up until this time it was just
00:12:23 --> 00:12:27 microbial just that was it um that's
00:12:27 --> 00:12:30 that's correct um so uh and the thinking
00:12:30 --> 00:12:31 yes it was it was single- celled
00:12:31 --> 00:12:34 organisms until that time and they they
00:12:34 --> 00:12:36 were around for you know three billion
00:12:36 --> 00:12:39 years or so um that that nothing
00:12:39 --> 00:12:40 happened except these single cell
00:12:41 --> 00:12:44 organisms uh principally C bacteria they
00:12:44 --> 00:12:46 just did their thing and got on with
00:12:46 --> 00:12:49 life but didn't evolve in any way uh but
00:12:49 --> 00:12:53 the end this this end of the glacial
00:12:53 --> 00:12:57 period was such a sort of Rapid climate
00:12:57 --> 00:13:00 change by the standard of the of the
00:13:00 --> 00:13:02 time by geological standards that the
00:13:02 --> 00:13:05 thinking is that you'd got a almost an
00:13:05 --> 00:13:11 arms race uh to adapt um to to to to
00:13:11 --> 00:13:14 this new situation where the microbes
00:13:14 --> 00:13:16 are not permanently in deep freeze
00:13:16 --> 00:13:18 you've got a warming climate and the and
00:13:18 --> 00:13:21 the evolution of the microbes kicks in
00:13:21 --> 00:13:23 at a much higher level than it was
00:13:23 --> 00:13:26 before and that is where uh we think
00:13:26 --> 00:13:28 that the multicell organism started to
00:13:28 --> 00:13:29 be
00:13:29 --> 00:13:32 and that's what are the ancestors of all
00:13:32 --> 00:13:34 the animals that we see today Yeah so
00:13:34 --> 00:13:37 basically those who survived the Thor or
00:13:37 --> 00:13:40 adapted to it uh created Life as we know
00:13:40 --> 00:13:44 it yeah that's just extraordinary um
00:13:44 --> 00:13:47 sort of factor to come out of it the
00:13:47 --> 00:13:49 other thing I and I correct me if I'm
00:13:49 --> 00:13:51 wrong but these rocks we were talking
00:13:51 --> 00:13:53 about in Ireland and Scotland and
00:13:53 --> 00:13:57 Australia and everywhere else uh the
00:13:57 --> 00:13:59 reason that these are so different is I
00:13:59 --> 00:14:01 believe these were rocks that actually
00:14:01 --> 00:14:05 stuck out of the ice is that
00:14:05 --> 00:14:09 correct during yes they may have done or
00:14:09 --> 00:14:13 or at least been subject to less glacial
00:14:13 --> 00:14:16 activity so yes they they they may have
00:14:16 --> 00:14:18 you know had only a thin layer of ice
00:14:18 --> 00:14:19 over them rather than be under
00:14:19 --> 00:14:23 kilometers of ice um so I think you're
00:14:23 --> 00:14:25 right there and and and just to to
00:14:25 --> 00:14:27 confirm you're quite right that some of
00:14:27 --> 00:14:29 these rocks are in Ireland as well
00:14:29 --> 00:14:31 uh I hadn't spotted that Andrew in my
00:14:31 --> 00:14:34 reading of the paper uh but yes so
00:14:34 --> 00:14:39 you've got um uh particularly you've got
00:14:39 --> 00:14:42 uh these rocks on some of the Scottish
00:14:42 --> 00:14:43 islands there these are small islands
00:14:44 --> 00:14:47 called the gav uh and it's um basically
00:14:47 --> 00:14:51 in the west of Scotland uh it's under
00:14:51 --> 00:14:53 the portas formation this is a
00:14:54 --> 00:14:56 geological area poas very well known to
00:14:56 --> 00:14:57 Scots people because it's the name of a
00:14:57 --> 00:15:00 well-known pipe tune um so let me quote
00:15:00 --> 00:15:03 from one of the authors of this work um
00:15:03 --> 00:15:07 and he's he's actually a PhD candidate
00:15:07 --> 00:15:11 at the univers University College London
00:15:11 --> 00:15:13 the layers of rocks Exposed on the
00:15:13 --> 00:15:16 garelic are globally unique underneath
00:15:16 --> 00:15:18 the Rocks laid down during the
00:15:18 --> 00:15:21 unimaginable cold of the glaciation a 70
00:15:21 --> 00:15:24 M of older carbonate rocks formed in
00:15:24 --> 00:15:27 tropical waters these layers record a
00:15:27 --> 00:15:29 tropical marine environment with
00:15:29 --> 00:15:31 flourishing s of bacterial life that
00:15:31 --> 00:15:33 gradually became cooler marking the end
00:15:33 --> 00:15:35 of a billion years or so of a temperate
00:15:35 --> 00:15:38 climate on Earth um most areas of the
00:15:38 --> 00:15:40 world are missing this remarkable
00:15:40 --> 00:15:43 transition because the ancient glaciers
00:15:43 --> 00:15:45 scraped and eroded the way the Rocks
00:15:45 --> 00:15:47 underneath but in Scotland by some
00:15:47 --> 00:15:49 miracle the transition can be seen and I
00:15:49 --> 00:15:51 think that's underlining what you said
00:15:51 --> 00:15:52 they were either sticking up through the
00:15:53 --> 00:15:55 ice or they weren't particularly deeply
00:15:55 --> 00:15:58 covered by ice so it's minerals and uh
00:15:59 --> 00:16:01 radiometric dating of the minerals that
00:16:01 --> 00:16:04 have allowed this discovery to to to be
00:16:04 --> 00:16:07 made yeah it's incredible isn't it uh
00:16:07 --> 00:16:08 all the answers are right there in front
00:16:08 --> 00:16:11 of us in the dirt sometimes simple as
00:16:11 --> 00:16:14 that yeah that's how we it's we know so
00:16:14 --> 00:16:17 much about the history of not just our
00:16:17 --> 00:16:19 planet but the you know the the other
00:16:19 --> 00:16:21 planets of the solar system just learned
00:16:21 --> 00:16:23 from looking at the Rocks that's right
00:16:23 --> 00:16:26 yeah fantastic uh if you'd like to read
00:16:26 --> 00:16:29 the article or chase up that story it's
00:16:29 --> 00:16:31 uh on the cosmos
00:16:31 --> 00:16:33 magazine.com website this is Space Nuts
00:16:33 --> 00:16:39 Andrew Dunley here with Professor Brad
00:16:39 --> 00:16:42 Watson also Space Nuts uh speaking of
00:16:42 --> 00:16:45 dirt Fred uh we've got we've got the
00:16:45 --> 00:16:49 dirt on the dinosaur asteroid we uh uh
00:16:49 --> 00:16:51 we now know thanks to a new study where
00:16:51 --> 00:16:55 it came from this is fascinating too it
00:16:55 --> 00:16:57 is that's right uh and you know it's not
00:16:57 --> 00:16:59 that long ago that people people were
00:16:59 --> 00:17:01 really still speculating about where the
00:17:01 --> 00:17:05 remnants of this asteroid was uh we're
00:17:05 --> 00:17:07 now pretty certain that uh it's in the
00:17:07 --> 00:17:11 chickalo ba Basin in the Gulf of Mexico
00:17:11 --> 00:17:15 that that is the uh the site which uh
00:17:15 --> 00:17:17 actually was the impact site of this
00:17:17 --> 00:17:20 asteroid so what you can do is you can
00:17:20 --> 00:17:23 look at the the Rocks um that you find
00:17:23 --> 00:17:25 in that region once again we're looking
00:17:25 --> 00:17:29 down at the dirt and um but basically
00:17:29 --> 00:17:32 look to see whether we know of anything
00:17:32 --> 00:17:36 like it out there in the solar system um
00:17:36 --> 00:17:37 and
00:17:37 --> 00:17:42 the bottom line is that yes we do find
00:17:42 --> 00:17:45 that uh in in particular and this is
00:17:45 --> 00:17:47 work being done at the University of
00:17:47 --> 00:17:53 cologne in Germany um the uh the element
00:17:53 --> 00:17:57 ruthenium um is basically a chemical
00:17:57 --> 00:17:59 marker if I can put it that way W that
00:18:00 --> 00:18:03 is found in the debris around the chick
00:18:03 --> 00:18:06 salum impactor and apparently in other
00:18:06 --> 00:18:08 sediment around the world because the
00:18:08 --> 00:18:10 debris from that explosion spread all
00:18:10 --> 00:18:12 around the world it was so you know such
00:18:12 --> 00:18:17 a uh such a a major piece of uh piece of
00:18:17 --> 00:18:21 explosive material it was only explosive
00:18:21 --> 00:18:22 because it hit the ground at a very high
00:18:22 --> 00:18:25 speed probably 30 or 40 kilometers per
00:18:25 --> 00:18:28 second um but the the fingerprint of
00:18:28 --> 00:18:31 ruini has been found in that debris and
00:18:31 --> 00:18:34 it turns out that that
00:18:34 --> 00:18:38 coincides with rocks in the the main
00:18:38 --> 00:18:41 asteroid belt that's the region between
00:18:41 --> 00:18:45 Mars and Jupiter but at the outer edge
00:18:45 --> 00:18:48 uh outer edge of the main asteroid belt
00:18:48 --> 00:18:50 not sort of not the kind of place you'd
00:18:50 --> 00:18:52 expect you would think if the if that
00:18:52 --> 00:18:54 rock could come from uh the asteroid
00:18:54 --> 00:18:56 belt you'd think it would be the near
00:18:56 --> 00:18:58 the inner Edge but the chemical um
00:18:58 --> 00:19:00 specifics tell you that it's actually at
00:19:00 --> 00:19:05 the outer age uh and um that is really
00:19:05 --> 00:19:08 very very interesting deduction uh who
00:19:08 --> 00:19:10 would have thought that we we were be
00:19:10 --> 00:19:12 able to pinpoint where that asteroid
00:19:12 --> 00:19:14 came from uh 66 million years after the
00:19:15 --> 00:19:18 event uh and um maybe
00:19:18 --> 00:19:20 the yeah I guess they worked it out on
00:19:20 --> 00:19:22 the chemical composition elements rather
00:19:22 --> 00:19:23 than
00:19:23 --> 00:19:26 backtracking yes that's right um it's it
00:19:27 --> 00:19:28 we don't have enough information to
00:19:28 --> 00:19:29 backtrack track we don't know what angle
00:19:29 --> 00:19:32 it came in at or you know what its orbit
00:19:32 --> 00:19:34 was before it collided with Earth so
00:19:34 --> 00:19:36 it's it's all about chemistry is this
00:19:36 --> 00:19:40 and um and in particular some quite uh
00:19:40 --> 00:19:42 quite sophisticated well I suppose you
00:19:42 --> 00:19:44 call it chemical physics because they're
00:19:44 --> 00:19:48 using radiation techniques uh basically
00:19:48 --> 00:19:50 to to to look for these levels of
00:19:50 --> 00:19:54 ruthenium uh in in the basically in the
00:19:54 --> 00:19:58 debris from the uh from the um asteroid
00:19:58 --> 00:20:03 uh crater and and surroundings uh and um
00:20:03 --> 00:20:06 basically uh you know looking at uh how
00:20:06 --> 00:20:09 it Compares with other um asteroid
00:20:09 --> 00:20:13 impacts and carbonous meteorites which
00:20:13 --> 00:20:16 also come from that region of the of the
00:20:16 --> 00:20:17 solar
00:20:17 --> 00:20:20 system so what might have caused a rock
00:20:20 --> 00:20:23 from that particular part of the solar
00:20:23 --> 00:20:26 system to you know turn its attention to
00:20:26 --> 00:20:28 us did Saturn get upset and Chuck a rock
00:20:28 --> 00:20:30 at us or something
00:20:30 --> 00:20:34 is um it's probably uh it's it's
00:20:34 --> 00:20:39 probably um uh a a just a gravitational
00:20:39 --> 00:20:43 disturbance you know something that
00:20:43 --> 00:20:47 Disturbed the uh orbit of this asteroid
00:20:47 --> 00:20:49 in its comfortable zone of the asteroid
00:20:49 --> 00:20:51 belt maybe an interaction with another
00:20:51 --> 00:20:54 asteroid because when objects come
00:20:54 --> 00:20:56 together they needn't necessarily
00:20:56 --> 00:20:58 Collide but if they can interact with
00:20:58 --> 00:21:00 each other gravitationally so that one
00:21:00 --> 00:21:02 of them gets thrown out of of of its
00:21:02 --> 00:21:05 orbits and you know it's possible that
00:21:05 --> 00:21:07 that would have been the case it's kind
00:21:07 --> 00:21:09 of like being in a crowd at a Chinese
00:21:09 --> 00:21:10 supermarket really
00:21:10 --> 00:21:14 that's that's what it's like yes yes I
00:21:14 --> 00:21:16 you didn't want to go that way but you
00:21:16 --> 00:21:19 ended up you have to you have to go that
00:21:19 --> 00:21:21 way yeah just because everything's so
00:21:21 --> 00:21:23 crowded it's it's it's a bit like that
00:21:23 --> 00:21:27 the um um the thing is that that event
00:21:27 --> 00:21:31 whatever Ed out of its comfortable orbit
00:21:31 --> 00:21:33 that might have happened a long time
00:21:33 --> 00:21:38 before the 66 million Year date a ago uh
00:21:38 --> 00:21:40 that we for the uh for the impact for
00:21:40 --> 00:21:42 the extinction of the dinosaurs so it
00:21:42 --> 00:21:44 might have been in a in an orbit that
00:21:44 --> 00:21:46 intersected the Earth's orbit for a long
00:21:46 --> 00:21:49 long time uh before the crunch finally
00:21:49 --> 00:21:51 came when it tried to be in the same
00:21:51 --> 00:21:53 place at the same time as the Earth so
00:21:53 --> 00:21:55 yes so so we there's details for this
00:21:55 --> 00:21:58 story that we still have a long way to
00:21:58 --> 00:22:02 finding out um but it may well have been
00:22:02 --> 00:22:03 as I said it's either a collision with
00:22:03 --> 00:22:08 another asteroid or maybe even something
00:22:08 --> 00:22:10 like the gravitational pull of gas
00:22:10 --> 00:22:15 giants maybe Jupiter uh perturbed that
00:22:15 --> 00:22:16 object's orbit in such a way that it
00:22:17 --> 00:22:18 interacted with another asteroid and got
00:22:19 --> 00:22:21 got thrown out of uh thrown out of the
00:22:21 --> 00:22:23 asteroid belt we probably will never
00:22:23 --> 00:22:25 know that uh it's interesting enough I
00:22:25 --> 00:22:27 think to to discover whereabouts it came
00:22:27 --> 00:22:30 from yes the other thing that came out
00:22:30 --> 00:22:33 of this is that it all but writes off
00:22:33 --> 00:22:36 that this was a comet impact yeah um but
00:22:37 --> 00:22:38 not
00:22:38 --> 00:22:40 absolutely yeah that's right there's
00:22:40 --> 00:22:43 still uh there's still a possibility but
00:22:43 --> 00:22:45 you know comets are a different beast
00:22:45 --> 00:22:47 from from asteroids they're they contain
00:22:47 --> 00:22:50 lots of ice uh as well as The Rock and
00:22:50 --> 00:22:54 that means that the chemistry of the the
00:22:54 --> 00:22:56 residual material from the impact would
00:22:56 --> 00:22:59 have different properties uh so I think
00:22:59 --> 00:23:03 um it's you know you can never say never
00:23:03 --> 00:23:06 but the the the body of opinion seems to
00:23:06 --> 00:23:08 be that it was actually an asteroid
00:23:08 --> 00:23:11 rather than a comet yeah I do have just
00:23:11 --> 00:23:13 one more question about this story and
00:23:13 --> 00:23:15 this is the most important one for it
00:23:15 --> 00:23:19 most important you mentioned the element
00:23:19 --> 00:23:21 renum yes so was the person who
00:23:22 --> 00:23:25 discovered that named
00:23:25 --> 00:23:27 Ruth um that's a good question I'd have
00:23:27 --> 00:23:29 to take that one on noticed but my guess
00:23:29 --> 00:23:32 is that that's where the name came
00:23:32 --> 00:23:36 from maybe maybe it was somebody who was
00:23:36 --> 00:23:39 ruthless and they thought yeah I'll call
00:23:39 --> 00:23:41 it ruthenian because I'm ruthless who
00:23:41 --> 00:23:43 knows that yeah yeah that's that's a
00:23:43 --> 00:23:46 thought too uh that story if you would
00:23:46 --> 00:23:50 like to read it is available at
00:23:50 --> 00:23:53 space.com this is Space Nuts Andrew
00:23:53 --> 00:23:59 Dunley here with Professor Fred Watson
00:23:59 --> 00:24:02 and I feel fine Space Nuts uh now Fred
00:24:02 --> 00:24:05 to the so-called crisis in cosmology
00:24:05 --> 00:24:08 we're talking about uh the the Hubble
00:24:08 --> 00:24:10 tension now we've we've done this story
00:24:10 --> 00:24:13 a few times over the years this this is
00:24:13 --> 00:24:17 where the basically the expansion speed
00:24:17 --> 00:24:20 of the Universe um depending on how how
00:24:20 --> 00:24:20 you
00:24:20 --> 00:24:23 calculate uh that number comes up with
00:24:23 --> 00:24:25 two different answers and theyve never
00:24:25 --> 00:24:28 been able to figure out why but now
00:24:28 --> 00:24:29 they're starting to think well there's
00:24:30 --> 00:24:32 no crisis at all everything's
00:24:32 --> 00:24:37 right um yes so
00:24:37 --> 00:24:41 um let me just explain how this this
00:24:41 --> 00:24:43 tension the Hubble tension comes about
00:24:43 --> 00:24:45 yeah uh because there are there are two
00:24:45 --> 00:24:50 ways of of measuring uh the expansion of
00:24:50 --> 00:24:51 the
00:24:51 --> 00:24:55 universe uh one uses standard candles
00:24:55 --> 00:24:58 and the other uses a standard ruler um
00:24:58 --> 00:25:00 and put it that way so the standard
00:25:00 --> 00:25:03 candle is taking that first um if you
00:25:03 --> 00:25:05 know how bright your candle is then you
00:25:05 --> 00:25:07 can work out how far away it is from you
00:25:07 --> 00:25:10 uh because you you know you know it's
00:25:10 --> 00:25:11 real brightness it's intrinsic
00:25:11 --> 00:25:14 brightness then you can work out what's
00:25:14 --> 00:25:18 is going on uh in terms of be because we
00:25:18 --> 00:25:20 know the way light gets fainter we know
00:25:20 --> 00:25:22 the rule by which light gets fainter As
00:25:22 --> 00:25:23 you move to greater and greater
00:25:24 --> 00:25:25 distances it's what we call the inverse
00:25:25 --> 00:25:28 Square law um it goes as the square of
00:25:28 --> 00:25:29 the the distance or one over the square
00:25:29 --> 00:25:32 of the distance so uh standard candles
00:25:32 --> 00:25:36 are usually stars in
00:25:36 --> 00:25:40 galaxies uh and in fact this is what uh
00:25:40 --> 00:25:42 led us detect the expansion of the
00:25:42 --> 00:25:45 universe in the first place because u in
00:25:45 --> 00:25:47 the early years of the last century
00:25:47 --> 00:25:51 around 1900 um a group of astronomers uh
00:25:51 --> 00:25:54 in the United States measured the
00:25:54 --> 00:25:55 intrinsic brightness of a particular
00:25:55 --> 00:25:57 kind of variable star one whose
00:25:57 --> 00:25:58 brightness varies
00:25:58 --> 00:26:01 uh but it varies in a in a periodic way
00:26:01 --> 00:26:02 and it turns out that there's a
00:26:02 --> 00:26:05 relationship between how frequently it
00:26:05 --> 00:26:07 varies and what the intrinsic brightness
00:26:07 --> 00:26:09 is and you usually take it at Peak
00:26:09 --> 00:26:10 brightness or minimum brightness
00:26:10 --> 00:26:12 whichever it doesn't doesn't really
00:26:12 --> 00:26:14 matter as long as you know what it is um
00:26:14 --> 00:26:16 and so that's the time oned way of
00:26:16 --> 00:26:19 working out how far away galaxies are uh
00:26:19 --> 00:26:22 to look for these variable stars and
00:26:23 --> 00:26:27 then basically uh look at um you know
00:26:27 --> 00:26:28 how bright they look to
00:26:28 --> 00:26:31 and from that work out the distance uh
00:26:31 --> 00:26:33 and that lets you produce a value for
00:26:33 --> 00:26:35 what we call the Hubble constant which
00:26:35 --> 00:26:39 is the number that basically tells you
00:26:39 --> 00:26:42 how fast the universe is expanding uh
00:26:42 --> 00:26:44 the Hubble constant is in units of
00:26:44 --> 00:26:47 kilometers per second per megap par but
00:26:47 --> 00:26:49 we don't really need to worry about that
00:26:49 --> 00:26:50 because at the moment all we're
00:26:50 --> 00:26:52 interested in it is the number and so
00:26:52 --> 00:26:56 until now uh the best estimates uh from
00:26:56 --> 00:26:58 the standard candles in other words the
00:26:58 --> 00:27:04 seid variables have come out at about 74
00:27:04 --> 00:27:07 km/s MEAP Parc but then the standard
00:27:07 --> 00:27:10 ruler method is uh looking back at the
00:27:10 --> 00:27:11 flash of the Big Bang the cosmic
00:27:11 --> 00:27:13 microwave background radiation which we
00:27:13 --> 00:27:16 see uh as it was about 13 billion years
00:27:16 --> 00:27:19 ago and there are features in that
00:27:19 --> 00:27:23 variation which uh have separations that
00:27:23 --> 00:27:25 we know would be characteristic of a
00:27:25 --> 00:27:28 certain the T particular time and and
00:27:28 --> 00:27:29 what we're talking about here when I say
00:27:29 --> 00:27:33 features I mean Peaks and troughs in the
00:27:33 --> 00:27:34 temperature of the Big Bang effectively
00:27:34 --> 00:27:37 what you're looking at um and from that
00:27:37 --> 00:27:39 you can also deduce the Hubble constant
00:27:39 --> 00:27:43 the expansion rate as it is today uh but
00:27:43 --> 00:27:45 the answer you get from that is
00:27:45 --> 00:27:48 67.5 kilomet per second per megap par
00:27:48 --> 00:27:51 yeah which is round about 6 and a half
00:27:51 --> 00:27:53 kilometers per second per MEAP second
00:27:53 --> 00:27:55 different from the other one and that is
00:27:55 --> 00:27:58 now we're in such a precise era that now
00:27:58 --> 00:28:02 has people worried um so what's happened
00:28:02 --> 00:28:05 well the same team who've done a huge
00:28:05 --> 00:28:07 amount of this work in the past led by
00:28:07 --> 00:28:10 um Dr Wendy Freeman fredman one of the
00:28:10 --> 00:28:13 big names in this kind of Science in the
00:28:13 --> 00:28:17 United States uh Wendy and her team have
00:28:17 --> 00:28:21 used our new toy the web the James web
00:28:21 --> 00:28:22 Space
00:28:22 --> 00:28:24 Telescope we always knew it would it
00:28:24 --> 00:28:27 would solve this problem we knew it
00:28:27 --> 00:28:28 would certainly help it would either
00:28:28 --> 00:28:30 make it worse or it would solve it and
00:28:30 --> 00:28:32 yeah you're right to cut to the chase
00:28:32 --> 00:28:34 it's probably solved it because it's now
00:28:34 --> 00:28:40 looking as though the method um is more
00:28:40 --> 00:28:41 like that you know the method where you
00:28:41 --> 00:28:42 measure the brightness of these variable
00:28:42 --> 00:28:45 stars is giving an answer more like 70
00:28:45 --> 00:28:47 kilometers per second per Mega which is
00:28:47 --> 00:28:50 much closer to that 67.5 that you get
00:28:50 --> 00:28:51 from the cosmic microwave background
00:28:51 --> 00:28:54 radiation and it turns out that when you
00:28:54 --> 00:28:57 think about the the error uh potential
00:28:57 --> 00:29:00 error of both of them then it overlaps
00:29:00 --> 00:29:02 so in that regard you've got something
00:29:02 --> 00:29:04 that falls within the error bounds of
00:29:04 --> 00:29:06 both of these methods and so maybe we
00:29:06 --> 00:29:08 are seeing the right answer at last so
00:29:08 --> 00:29:11 it it basically brings it back to an
00:29:11 --> 00:29:14 average that's right both methods yeah
00:29:14 --> 00:29:16 yes yeah you know when I started my
00:29:16 --> 00:29:21 career Andrew um there were two camps uh
00:29:21 --> 00:29:23 and basically they were using similar
00:29:23 --> 00:29:27 methods uh one said that the uh Hubble
00:29:27 --> 00:29:29 constant was 50 kilm per second per Mega
00:29:29 --> 00:29:31 second the other said it was 100 kilom
00:29:32 --> 00:29:33 per second per Mega second they were
00:29:33 --> 00:29:34 both
00:29:34 --> 00:29:36 right they thought they were both right
00:29:37 --> 00:29:38 and it turned out that the the answer
00:29:38 --> 00:29:40 the real answer was the average of them
00:29:40 --> 00:29:45 70 or 75 of that there you go um pretty
00:29:45 --> 00:29:47 simple solution at the end of the day
00:29:47 --> 00:29:49 but a lot of hard work went into went
00:29:49 --> 00:29:52 into finding it we yeah we hope that's
00:29:52 --> 00:29:53 that resolves the Hubble tension it
00:29:53 --> 00:29:56 would be great hopefully Cosmic
00:29:56 --> 00:29:58 disappeared yeah yeah I wouldn't be be
00:29:58 --> 00:29:59 surprised though in months to come
00:29:59 --> 00:30:02 somebody comes up with a debunking
00:30:02 --> 00:30:05 theory well there you go it could happen
00:30:05 --> 00:30:08 it could happen but um at this point in
00:30:08 --> 00:30:10 time looks like it might have been
00:30:10 --> 00:30:12 resolved this has been frustrating for a
00:30:12 --> 00:30:15 long time but uh may may be as simple as
00:30:15 --> 00:30:18 oh hang on a sec you're both right and
00:30:18 --> 00:30:20 here's why yeah yeah yeah um that story
00:30:21 --> 00:30:24 is on sitech daily.com um question
00:30:24 --> 00:30:25 without notice Fred that's come through
00:30:25 --> 00:30:28 from one of our live viewers uh why hi
00:30:28 --> 00:30:32 Wayne um this harks back to the snowball
00:30:32 --> 00:30:35 Earth story we did uh Wayne asks so
00:30:35 --> 00:30:38 wonder how much bigger the diameter of a
00:30:38 --> 00:30:40 frozen Earth would be to the current
00:30:40 --> 00:30:42 Earth do we have any idea what that
00:30:42 --> 00:30:45 might have been yeah it probably wasn't
00:30:45 --> 00:30:49 that much different um it um you know I
00:30:49 --> 00:30:52 mean at the moment a lot of that water's
00:30:52 --> 00:30:53 still there but it's
00:30:53 --> 00:30:56 wet uh and you know and this is now it's
00:30:56 --> 00:30:59 it's turned into ice so um it's not
00:30:59 --> 00:31:01 going to be it's certainly not going to
00:31:01 --> 00:31:05 be Kil um tens of kilometers different
00:31:05 --> 00:31:07 um it might be a few kilometers
00:31:07 --> 00:31:09 different um on average and I'm talking
00:31:09 --> 00:31:11 about the average uh but but I don't
00:31:11 --> 00:31:13 think it would uh you know it wouldn't
00:31:13 --> 00:31:14 have turned into a gaps giant or
00:31:14 --> 00:31:16 anything like that that's an interesting
00:31:16 --> 00:31:17 question though because we think it's
00:31:17 --> 00:31:20 because of Frozen water out in the
00:31:20 --> 00:31:22 depths of the solar system adding to the
00:31:22 --> 00:31:25 mass of the gas giants as they were
00:31:25 --> 00:31:27 being formed we think that is one reason
00:31:27 --> 00:31:28 why they be became so big because they
00:31:28 --> 00:31:32 had enough boun to hold on to a a gas
00:31:32 --> 00:31:35 envelope um and so it's a good question
00:31:35 --> 00:31:37 to to ask that at what difference would
00:31:37 --> 00:31:39 the ice make but it but this is really
00:31:39 --> 00:31:41 just a surface layer of ice rather than
00:31:41 --> 00:31:43 a solid block of ice which may be at the
00:31:43 --> 00:31:47 core of the of the Gus Giants indeed all
00:31:47 --> 00:31:48 right thank you Wayne nice to get
00:31:48 --> 00:31:50 questions without notice while we're
00:31:50 --> 00:31:52 going out live during our recording
00:31:52 --> 00:31:54 sessions good to hear from you uh Fred
00:31:54 --> 00:31:56 we're just about done thank you very
00:31:56 --> 00:31:59 much a pleasure Andrew good to talk and
00:31:59 --> 00:32:01 uh some interesting topics and there'll
00:32:01 --> 00:32:04 be more next week indeed there will
00:32:04 --> 00:32:06 thanks Fred uh Professor Fred whats an
00:32:06 --> 00:32:08 astronomer at large don't forget to
00:32:08 --> 00:32:10 check us out online Space Nuts
00:32:10 --> 00:32:13 podcast.com SPAC nats.io where you can
00:32:13 --> 00:32:14 check out the shop maybe become a
00:32:14 --> 00:32:16 supporter of the podcast if you're
00:32:16 --> 00:32:19 interested um just have a bit of a flick
00:32:19 --> 00:32:21 around and if you follow us on social
00:32:21 --> 00:32:23 media don't forget to like us follow us
00:32:23 --> 00:32:25 add us to your favorites list or click
00:32:25 --> 00:32:27 the Subscribe button depending on which
00:32:27 --> 00:32:28 platform
00:32:28 --> 00:32:31 it is uh and uh thanks to Hugh in the
00:32:31 --> 00:32:33 studio as always and from me Andrew
00:32:33 --> 00:32:35 Dunley we will see you again soon on the
00:32:35 --> 00:32:39 very next episode of Space Nuts bye-bye
00:32:39 --> 00:32:41 Space Nuts you'll be listening to the
00:32:41 --> 00:32:43 Space Nuts
00:32:43 --> 00:32:46 podcast available at Apple podcasts
00:32:46 --> 00:32:49 Spotify iHeart radio or your favorite
00:32:49 --> 00:32:51 podcast player you can also stream on
00:32:51 --> 00:32:54 demand at bites.com this has been
00:32:54 --> 00:32:56 another quality podcast production from
00:32:56 --> 00:33:00 bites.com B