14:30
we're in space and we're talking about a really weird object in the solar system there a lot of weird objects in the solar system but this one caught my eye partly because it feels like these videos bleed into every aspect of my life I come across ideas for videos uh doing very unexpected things and this one was inspired by a book so I've been reading a book called another year of wonder by the broadcaster and musician clemency Burton Hill in which every day there's a little entry where she describes a piece of music and you can explore a little bit about the history and the meaning of the music and listen to it and then go about your day and so a little while ago on the 4th of January
uh the entry for that day was actually a piece of music that was inspired by astronomy so that caught my attention and I listened to the music and I read about the object and I got so intrigued about this interesting object that I thought well just got to make a video about it so here we are the object is the asteroid 4179 totis how do you write a piece of music about an asteroid well of course you know in there's lots of Music That's inspired by the natural world and including astronomy so the probably the most famous uh bit of music uh inspired by astronomy is uh Holst The Planets and even if you don't think you know this piece I'm sure that you've probably heard bits and pieces of it because it
is just so iconic and so familiar but this piece about the asteroid is by a Finnish composer Kaa SRA you're gonna put this in aren't you it's written on the screen Kio and it was actually commissioned by the um Berlin philarmonic Orchestra to go along with the planets um by Sir Simon Rattle the conductor and so this is a very modern piece of music it has to be modern because this asteroid was only discovered in 1989 so it's quite a recent discovery um and it's interesting for a number of reasons first of all it's a very close neighbor somewhat uncomfortably close actually because it's a near Earth asteroid its orbit as it goes around the sun takes it very close to the orbit of Earth all the way out to near Jupiter so crossing the
orbit of Mars so it's in this funny resonance between Jupiter and the Earth and the Sun so its orbit is set up so that every one time it goes around the sun we GRE around four times but it also comes very close to the Earth so since it was discovered in 1989 it's made multiple close passages so in 2004 it came with within four lunar distances of the earth so you think about how close the Moon is it's not really close but you know in solar system distances this is close and it was only four times further away so I'll say at this point it's okay we don't have to be worried about this thing we've got a good eye on it and we know pretty much uh what its orbit is and there is essentially zero
chance uh that it's going to IED with Earth so like many asteroids it is a rocky body and it's not necessarily a regular Rocky body so the advantage of it coming close is that we can actually observe it and we can even send things out to have a look and so there are a number of asteroids and solar system bodies that we've actually sent satellites out to go and look at sometimes even land and so this one it wasn't a targeted Mission but in 2012 the Chinese spacecraft uh Chong a which was a lunar probe did a very close flyby uh from about three and a bit kilometers above the surface and confirmed that it was this lumpy Rocky body that was full of craters and a great big Basin and had this very irregular structure the
asteroid is named after a Celtic god called tutatis this really bugged me when I first read this cuz I thought that sounds really familiar something about that sounds really familiar but I'm not up on Celtic gods and I read a little bit more about it and say it's also woried by the GS and I thought oh yeah that brings back something from my childhood so Brady I don't know if you were a reader of asteris or were you a Tintin kind of person I wasn't either I'm ashamed to say okay so I was in asteris so I pulled this one off the shelf and sure enough on the first page we've got a phrase that appears over and over again in these books Oh by two Tartus yeah so just an oath and that's that's where it
had embedded in my head so that's that's the connection I made so I got off topic because I was saying that we have learned about this asteroid in a number of ways um one by observing it from the ground and we can do this unusually not just by collecting photons that bounce off it which is what we normally do as astronomers but this was close enough that we could use radar so the NASA gold stone facility located in California a big 17m radio dish actually pinged radio waves off this object and got them back and was able to make um sort of a little video which we can show you about what it looked like this is probably a contact binary so probably two bodies that were pulled together by gravity but
are not really a big solid body and gravity hasn't smooshed them together into a nice spherical shape I'm meant to bring in a sweet potato as an example because that's the thing it most looks like in the images and I forgot but I cobbled together a an object from whatever I had in my office which were two horse chestnuts stuck together um by Blu Tac but I think this kind of demonstrates you can compare it to the image that it's it's a very elongated bit uh it's a very elongated object and it's got kind of two distinct lobes to it and it really does look like two things that were kind of stuck together so the object itself is about four uh close to 5 kilm along this axis and then
about two in the other axis so it's big enough that you really wouldn't want it to hit uh it would do a lot of damage if it hit the Earth but I found an interesting size comparison where you can see where it fits with respect to some of the other objects that we've kind of visited so it's about the same size as the nucleus of Hal's Comet it's a bit bigger than 67p which was another Comet that we spent quite a long time around but is a lot smaller than some of the other big um objects out there going back to the music and going back to the thing that got me interested about this object from the description in the book was this note about its rotation so they noted both the composer and the
original discoverers noted that it has kind of two different kinds of rotation so it rotates along its long axis uh with a period of about five days but that axis itself precesses so moves around it's pointing at different parts of the sky with a regular period of about seven days and what I like about the music and the composer is that they acknowledge that if you are standing on the asteroid you are not going to experience the same thing that we do here on Earth which is to see the regular rotation of the sky and the sun is never going to rise in the same place or set in the same place you're just kind of randomly tumbling through space and I think that's kind of I don't know makes you think about how the universe
is your perspective on the universe is quite different depending on where you're living in it Professor you're a galactic astronomer you love galaxies and stuff that's really far away mhm do asteroids get your juices flowing or do you look at them and think this is just gravel I want the big stuff it's kind of both so it's different parts of your brain right so the original part of my brain that just liked space stuff and just says wow to a wide variety of things says isn't that amazing that this thing we can find out that this thing is in our neighborhood we can track it we can learn about it and we can try to understand how it tells us about how the solar system and indeed the Earth formed yeah the uh extra Galactic astronomer in me
says oh this thing's just a piece of rock and it's getting in my way uh you know because asteroids sometimes do come across our field of view and sort of mess up our observations so I can hold both thoughts in my head at the same time when you do some of your work and you do these like huge surveys and you're looking at a picture of the sky like the picture behind you with all those galaxies with billions of stars and I can't imagine how many planets do you ever stop and think there are asteroids in there too there are little asteroids floating around little or is that just not even entering your mind yeah well Brady I will refer you back to the video that we made about that
picture many years ago um in which I talked about how in that case an asteroid did track across the field of view and I got very excited about this weird thing that was showing up and I excited went to one of my colleagues and said oh my goodness what is this and they said uh it's an asteroid so yeah you can have the connection between the two for sure but you don't think about the asteroids in the galaxies like in the galaxies no um that yeah I might think about planets I might think about individual Stars if I think really hard I might think about planets but no I don't think I go down to that I haven't until now and now I am thinking about those individual but like we've managed to
talk for like 10 minutes about this asteroid yeah and there's all those asteroids in those galaxies and imagine how many stories there are and how many interesting objects there are and collisions and it's we're going to be making videos for a long time we're not going to run out of things to talk about but yeah that's what astronomy gives you it gives you this crazy sense of perspective of both being incredibly tiny in the universe but also that there is so much out there um which is uniquely interesting that split the two things out they also found that there was a difference in how many heavy elements the Stars had in each of these clusters so we're talking things like yeah okay
fine helium but also mostly things like carbon oxygen nitrogen and obviously some of the traditionally more heavier Metals up to iron as well so the way that we find out if Stars contain those elements is we take a spectrum of the light from the star
