This Chris Hadfield guy is in the big leagues now - chatting with world renowned leading standup maths expert Matt Parker. Chris's life is going to be different now. He might become somebody.
Shout out to Buzz Aldrin. Not just the second man on the moon, but the guy who literally wrote the book (his PhD thesis) on translating the math of orbital mechanics into practical pilot mechanics for the early astronauts.
9:30 I couldn't resist checking the values. Using G = 6.674×10⁻¹¹ m³kg⁻¹s⁻² and M = 5.972×10²⁴ kg and r = 6357 km + 420 km = 6.777×10⁶ m we get that v = √( GM/r ) = √( (6.674×10⁻¹¹)(5.972×10²⁴)/(6.777×10⁶) m²s⁻² ) = √( 5.881 × 10⁷ m²/s² ) = 7669 m/s Yeah, that's 8 km/s, just like Chris Hadfield said 🤩
Matt AND Chris Hadfield, jeez that put a smile on my face. Regarding orbital mechanics, it always makes more sense to me to think of velocity as relative velocity (which of course it is).
If you have 2 weights connected with a spring, and you rotate them in empty space, you can tell their rotational velocity and angular speed by looking at how far the spring gets streched by the centripital force, even if your reference frame is rotating around with them. Similarly an orbiting body around earth has to have a certain velocity to stay in orbit and it is clear, that it is the lighter orbiting body moving around the earth and not the earth moving around the satellite... (theyre both moving around their shared center of mass but whatever), so if you can definitivly tell who is moving and how fast, how is it relative?
@@jeffreylebowski4927 in a frame of reference that is stationary with respect to the spinning springs, it looks like their inertia is driving them outwards. In a rotating reference frame, it looks like there's a force pushing them outwards. Both are correct, depending on your point of view. Rotation is just normal movement which is constantly changing. The only thing all observers agree on is the speed of light, which is where the theory of relativity kicks in, of course.
Put more bluntly, there is no absolute frame of reference, a 'universal' stationary reference frame can not exist (this can be shown experimentally). Hence, velocity is always relative.
6:50 Matt: "Get rid of an m from both sides, so I'm afraid your mass now doesn't matter..." Chris: **shrug and smirk** God damn he's cool Edit: Also, I appreciate his landmark numbers are coffee-centric: 9:18 "The time it takes to drink a cup of coffee" 11:47 "Our target was about the size of a coffee saucer"
It does matter if you have to fuel the shuttle. You can’t get away from the fact that they lose mass at each burn and a more massive shuttle is harder to change velocity since it has a certain amount of momentum. It won’t change the target velocity at the radius but it does matter what the mass of the shuttle is.
Skye Blue I get that. But they have to use acceleration to achieve a change in velocity and orbital distance. Just thought it was interesting how the high school level physics is being presented by the big guns. I wished they would have gone into the trickier stuff.
Hearing Chris Hadfield describe a portion of docking procedures as brute forcing it makes me feel better about how many kerbals I've trapped in orbit in KSP.
Docking in KSP can be (as soon as you are within a few hundred meters and at a relative stop) done very easily. On the first spacecraft, select "control from here" on the port you want to dock to, set the port you want to dock to on the second spacecraft as the target, and set SAS into point at target mode. On the second spacecraft (which must have RCS or thrust inline with the docking port), do the same, then gently thrust in to dock.
Zuthal Soranizc, yes, that’s all well and good, but in career mode docks aren’t available until after the first rescue mission. So needless to say my first few “dockings” were really just incredibly difficult near-identical orbit encounters. Later to save one crew on a large ship with no dock or electricity (forgot to add solar panels), I had to bring a rescue vessel directly beside, attach an engineering strut to hold them together, then EVA to attach some solar panels. It sure was nice after that when I finally unlocked docking ports!
Chris really does come across like a great guy. His son also runs a very high quality RUclips channel so he’s probably a great dad too! (The channel is called Rare Earth for those who don’t know.)
Like others here, I cannot recommend Rare Earth with Evan Hadfield too highly. It is without question one of the very best documentary channels out there.
I'm glad Chris is still making content and getting recognized, he's one of the coolest and most interesting people both on or off the planet. Just a nice, sincere, and humble guy too. An absolute pleasure to watch! Hope you can convince him to make more collabs lmao
You can tell he drinks a lot of coffee from all his analogies! Time it takes to drink a cup of coffee, target the size of a coffee saucer, the man is loaded up on caffeine
@@HaraldSangvik I remember the first time i got a 0m intercept. Let's say that i didn't brake on time and the impact destroyed the target and took my engine. I managed to land the surviving kerbals by deorbiting using rcs thrusters.
I was introduced to Matt on Tom Scott's channel, and I was introduced to Tom Scott because of an interview he had with Chris Hadfield. The cycle is complete.
Awesome that you got the legendary Chris Hadfield to make it onto your youtube channel. Classic physics problem explain by two great explainers. I loved the end about docking because it gave some insight onto what actually happens on the ships.
The speeding up to change orbit is similar to going up a hill on earth. To get a vehicle higher you need to speed up but when you reach the top you will have slowed down due to that kinetic energy becoming potential energy.
This feels like a symphony of presentation. You two are playing off each other wonderfully well. Actually, it’s just Chris playing amazingly off you. But it’s an exceptional video. ❤️
Love the physics 1 board, but love even more the introduction to the concept of "prox ops", helps me explain and understand a simple intuitive everyday concept more clearly.
Chris Hadfield is a rock star; not only did he do what we all wish we could do, but he’s so relaxed and humble about it it makes you respect him even more. Plus, it’s actually great seeing him chat with a good teacher like Matt 🙂
@@vallov4188 He was thinking about the triangles. Sometimes it's easier to use your hands to "see" some relations. I bet you that at least 9 out of 10 times you stand and watch a university level physics exam, you'll see most of the students doing signs like those (specially one with their thumb, index, and middle finger - it's the 'right-hand rule' -).
9:07 Mat. "and how long does it take between when you launch and when you get to that orbit?" Chris. "The rockets have to burn and accelerate you up to the right speed and the right angle, It takes somewhere just a little less than 9 minutes. From sitting here in Florida on the pad laying on your back, to the engine shutting off and being there weightless in orbit" Shame this wasn't asked slightly earlier, the tie up in time would have been awesome. Could have ended it with "Takes as much time as it's taken to watch this video up to ... *NOW* "
Really loved this one! I studied orbital mechanics in school, and now in my work I talk about the possibilities for rendezvous and proximity operations (RPO) all the time. It can be used for docking at the space station, or it might soon be used for cleaning up space junk.
At least an hour away, with almost nothing but swamp between Orlando and the coast. But I guess if the cruise ships can sail out of Orlando (seriously, they say that in their commercials) then I guess Matt can claim Kenedy is in Orlando, too.
@@AedarinOfMinecraft don't forget.. The Orlando tourism folks include any beach that they've been to as part of "Orlando Beaches" including Cocoa Beach and Clearwater Beach..
When you're coming from the UK, you start by getting on a course that will take you to Orlando, then when you get close, it's prox ops and you stop worrying about cities and you just move towards the space center.
wow... hearing Chris describe docking exactly how i experienced it in SimpleRockets 2 is surreal, doing calculated burns to get close to target, understanding how falling around the earth completely changes predictions of how it would move if it were linear paths, and then prox ops, trying to fly it manually and brute force the unconventional mechanics the rest of the way up to lining up on a saucer dish sized target... utterly perfect description of the brain processes required to fly in space
It's general enough to be applicable to virtually anything, and specific enough to still be meaningful for lots of things. Truly the best of languages.
Well, problems arise when we ty to apply maths to qualitative entities, like happiness. I mean, statistics is a great help, but it's still murky territory.
My first thought on seeing the thumbnail and "I'm in Orlando" intro was "Well of course they're disregarding physical distancing protocol... They're in Florida." (Yes, I saw the note that this was recorded in the before time, the long-long ago of February.)
One of the most revealing videos ever, for me personally. I had a vague idea of how docking is happening, but wow, you accelerate and the result is you're slowing down!! Oh boy... Huge thanks Matt and Chris !!
In my education for becoming a math teacher I created an exercise for students to derive these equations. It worked it's way up to determining the velocity increase needed for a hohmann transfer to Mars and determine at which day to launch so that Mars would be at the correct spot when you arrive there. It's the perfect way to connect differential calculus to physics.
I live close enough to KSC that I was hoping to see a beautiful Atlas IV night launch early this morning... They did a "hot-fire abort" instead. Meaning that they got all the way to T-minus 3 seconds and ignition but the engines didn't start and the rocket stayed on the launchpad. At least they didn't pull a Kerbal and have the second stage fire while still connected to the first stage.
Matt Parker, Chris Hadfield, Kennedy Space Centre, Space travel talk and my favourite type of maths?? This is the perfect formula for my favourite video :)
12:55 that beautiful moment when Matt's brain can't quite envision the real world execution of the maths he can work out all day long without out breaking a sweat. Not a dig either, but rather an observation about application vs. theoretical in any field, echoed by what Cmdr. Hadfield said earlier in the video about how in his job they don't do the maths in public but instead deal with the practicalities in real time. Outstanding video, made maths fun with two charming presenters.
This and the version with Chris describing launch and ascent are marvellous. Really needed a shout-out to the ‘computers’ who really made space flight possible and survivable in the 50’s and 60’s. Much better than my structural engineering prof who would fill the chalk board and then announce “it can be shown” and write down the answer. We were expected to remember the derivations in our exams!
After playing KSP with RSS and Principia. "I've landed a probe on the surface on the surface of Enceladus." After watching this video. "V is equal to what?"
Matt Parker and Chris Hadfield in one video about orbital mechanics(very basic math but the part from where he talks about docking was 'out of the world')!! Clicked instantly!!
When firing the rockets in orbit, it depends on if you do it prograde or retrograde. I learned this while playing Kerbal Space Program, introduced to me by Scott Manley
Tip: if you don't want to bother finding out the values of the gravitational constant G and Earth's mass M separately, you can instead use G*M = 9.8 * (Earth_radius)^2 (use SI units!).
@@JohnDoe-nq4du I would say that you are correct, but also that if you are not using SI units, you are not using units correctly. Also, I don't think it's wise to measure gravitational acceleration in feet or miles by square second (let's say).
Yes, indeed... *"because Math isn't chemistry."* You have a problem and in fact an enormous problem with "friction"(meaning you're interacting with the massive amount of energy generated from Sun interfering with our pristine math.) In other words upon achieving said "orbit"(hooray, both of us are falling together!) you soon discover that at this level of specificity (incradibly high velocities) you comparative "rates of falling" are hardly the same. In other words for any of this math to in fact make "mechanical sense" you need a constant that would also exist in similar domain. Not a "space person" but back of the envelope I would argue just use the Moon as your constant and "triangulate" (two separate maths now) what is an all too "need to fixed relative position." In the alternative you can just *GO* to the Moon and *LAND* there of course..
Awesome video, Chris is great! The discussion of orbital mechanics during docking really beings back my experiences in Kerbal Space Program over the years... You really have to keep in mind what your maneuvers will do to your orbit relative to your target and remember to be compensating for the drift that causes, even at short range you'll find yourself slowly circling around the target station or vessel if you hang out nearby too long without getting that solid connection made!
Indeed fascinating, that the necessary speed only depends on the radius, not on the characteristics of the object you want to fly around (as long as it fits in there without scratching the atmosphere or smacking into too much space debris ;) ).
Aerodynamic drag is actually a factor even for ISS, because of how huge its solar arrays are. So while shape and size of the ship/station doesn't change how fast you need to be going, it is a factor in how frequently you'll need to fire up the engines to stay up there.
@@Daniel-yy3ty Of course it does. If the body you want to orbit is heavier, you need to increase the speed to compensate for the extra gravitational pull. In other words, a 7000km (radial) orbit around earth requires a higher speed than a 7000km orbit around the moon.
"You don't want your speed to slow down. I guess that's the definition of being in orbit" In a circular orbit. It's the definition of being in a circular orbit.
Regarding the orbital mechanics at 12:40 ... I like to use a circle track as a good analogy (NASCAR or speed skating, or whatever works for you) When you speed up in orbit, you increase the size of your circle track. So even though you are going faster, the distance to complete a lap is further so it ends up taking longer to complete a lap. So, if you want to catch up with someone orbiting far far ahead of you, the easiest way is to actually slow down, thus decreasing your circle size. With a bit of proper calculations, you can slow down enough to meet perfectly up with them on the next go-around (just don't slow down by too much, or you'll crash into Earth, which is not ideal). Once you're within spitting range (proximity operations, as Chris Hatfield calls it), then you're going to be speeding up and slowing down in *tiny* increments, and too quickly for the velocity changes to have any impact on your circle track. So that's when you can just "brute-force" yourselves together.
My favourite orbital mechanics fact that wasn't mentioned: orbital period near the surface of a body is a function of density. Because the earth and moon are both rocky bodies (and therefore similar density), they both take about 90 minutes per orbit. All other rocky bodies will have similar orbital periods, regardless of size.
That doesn't seem quite right. Mass is proportional to r³ (assuming fixed density), and if r[body] ≈ r[orbit] then we get v² = kr³/r = kr², which means v ≈ r. Oh, but you're talking about period! So that's circumference over speed, both of which are proportional to radius, so that cancels out and we're left with just the constants. Neat.
As someone who did too much math in Kerbal Space program (with a mod called KerbalOS mod actually) the math checks out. The headaches comes when the orbit isn't a 2-body problem with a non-perfect circular orbit. Orbital eccentricity makes everything way harder.
3:05 A constant radius should the the exception to the rule. Any small imbalance of force through the radius would cause an elliptic orbit with some eccentricity.
2:56 This is why Matt specified, "We're now going to look at you A VERY SMALL MOMENT OF TIME IN THE FUTURE". After a sufficiently small difference in time, the radius doesn't change enough to have a significant effect on V (delta V is insignificant, and can be treated as 0).
@@TheDannyHamilton That's not the point. The point is that he has restrained his calculation to only circular orbits. If you want to be able to do any kind of maneuvering in orbit, you need to use an elliptical orbital model because any component of thrust colinear with center of the earth will cause eccentricity.
@@timharig If you're in a perfectly circular orbit, any component of thrust parallel to either your current motion or your current radius will add eccentricity. It's only a purely horizontal sideways thrust that will keep you moving at orbital speed for your current altitude and in a horizontal direction.
@@rmsgrey Hence the need for a elliptic orbital model. Because any time you add thrust, what you are really doing is changing which ellipse your orbit is following. (Or in the extreme case, another conic section.)
@@valentijnraw everywhere I've ever seen, a vector or is in bold or have an right pointing arrow on top of it. Because of my engineering background, i really fancy the arrow.
Man I am really thankful to Kerbal Space Program for teaching me all this stuff completely intuitively so now I can understand the math and all the technical thinking behind it. Having an empyrical understanding of orbital mechanic would have been pretty much impossible without a piece of software that lets you tinker around with virtual rockets. Beautiful video.
The shuttle's AP-101 computers had much more in common with the Apollo guidance computer than most people realize. The technology between the two is really only about 10 years, and it took five of them (four in sync and one for error checking) to get the needed reliability and redundancy. SpaceX was able to start from scratch using computer technology and interface improvements at least 50 years ahead of the shuttle. And even now there is a significant amount of pre-processing that is done on the ground to ensure success. Mr. Sulu's job isn't in jeopardy quite yet.
@@corwinchristensen260 True that said it is not inconceivable that Starfleet could have standard pre-defined orbits and such for much the same reason why we have standard flight levels using a standard altimeter setting in aviation. When you start having to manage large numbers of craft all while making sure to keep them a safe distance from each other such standardization becomes invaluable for making sure everyone is working on the same page. We already did the same for shipping and later aviation when they became popular so it's not exactly surprising a society that made heavy use of spaceflight would do likewise.
I love how you proved that the mass of the orbiting object didn't matter. You showed mathematically what Galileo said 400 years ago -- that all objects, no matter what their mass, will fall with the same acceleration. Awesome!
This is one of the assumption that went into Newton's equations. Therefore, it's kind of silly to say that Newton's equations prove that two objects follow the same trajectory in a gravitational field.
8:16 “If you were to hold a globe, and bring your eyeball down to maybe like a thumb-width, that’s how far we were from the surface” wow Hadfield uses intuition so much he seems to have forgotten both metric AND imperial lol 😂
Just a practical question: All the equations I've seen in school calculate a circular orbit, but no satellites do that. What is a *practical* relation between the circle and ellipsoid orbits, in terms of speed and energy?
If you average the apoapsis with the periapsis, you end up with a value known as the semimajor axis (SMA or simply lower-case a). Ignoring any atmospheric drag presented from an insufficient periapsis, and any gravitational inputs from additional bodies such as the moon, all bodies orbiting with the same SMA will have the same average velocity, even if the eccentricity of those orbits varies wildly. The ground-referenced speed of those orbiting bodies will change depending on their current altitudes, but they will all average out to be traveling at the same speed and orbital period. TLDR: a circle is just an averaged ellipsoid, and we lack the technology to orbit in (or even freehandedly draw) perfect circles.
Every geosynchronous orbit is circular, and I'm pretty sure that's where most of our satellites live (ignoring Starlink etc). Also the GPS satellite orbits are only about 2% off circular, though they aren't geosynchronous. It is true that they can only approximate circular orbits, but on the other hand there are a lot of satellites in approximately circular orbits.
@@patheddles4004 There are more satellites in low earth orbits than in geosynchronous ones, but other than that, you are right. Most satellites have approximately circular orbits.
I was confused about the higher orbital and slowing down thing until I remembered mechanical energy and total conservation of energy. Thank goodness!!!
3:36 I'm not sure if I understood it correctly but it you said "you're getting lower, you're slowing down" then that's incorrect. Neglecting the atmosphere, you are entering a lower and thereby faster Orbit. Thus, you speed up. This effect can be seen in very elliptical orbits. As you leave Apogee, you are getting closer to earth(thus getting lower) and speeding up til you reach Perigee, the lowest and fastest point in an Orbit
kerbal space program taught me everything I need it to know about orbital mechanics also I loved that you could see that the equations could be extended to elliptical orbits :)
One other formula that is quite interesting: if the circular orbit velocity, v at radius r is given by v^2 = GM(1/r), then to reach escape velocity starting at the same r is given by v^2 = GM(2/r) i.e. if you are in a circular orbit around any object. if you can increase your speed by a factor of SQRT(2) - i.e. increasing it by roughly 41%, then you will completely escape from orbit.
Astronauts are literally the only people I respect and adore whole heartedly without question. And Chris is definitely a huge part of that for me and so many other people like me. So great job Matt!
What a man! I wish I can do this once in my life although it is highly improbable. Thanks for the video Matt, it was great listening to Mr. Hadfield talking about his experience.
What a huge honour for Chris to meet the legendary Matt Parker
I laughed so hard at this
And conversely, too.
He IS legendary
Oh wow Matt knows Lucie Green too !
LOL
This Chris Hadfield guy is in the big leagues now - chatting with world renowned leading standup maths expert Matt Parker. Chris's life is going to be different now. He might become somebody.
He hit the big time when he went on holiday with Tom Scott.
The originator of the Parker Square, what a guy!
He was already doing stuff, I love that our astronauts (who are ok with it) are getting attention. He's a great explainer.
Chris who?
Yeah, nice of Matt to give him a break to the greater audience.
Shout out to Buzz Aldrin. Not just the second man on the moon, but the guy who literally wrote the book (his PhD thesis) on translating the math of orbital mechanics into practical pilot mechanics for the early astronauts.
Also punched a moon landing denier in the face.
@@garrysekelli6776 Say that to his face. I dare you.
One of the reasons they put him on Apollo 11. He could've flown the whole docking by hand if necessary.
Arif R Winandar - another reason to like him! 👍
Dr. Rondezvous himself.
"Thank you for comming along it's..." "I'VE BEEN TO ORBIT 3 TIMES!"
But seriously, he is one of, if not THE coolest astronaut out there.
Ofcourse he is! That's why hé is allowed to wear those awesome sunglasses, and Matt isn't.
Yep. Coolest human alive. Chris didn’t even need to bring those sunglasses: they spontaneously float onto his face as he steps outside.
I love how his voice sounds exactly like when he was in space.
There's a "deal with it" meme to make here
I don't know, Chris Hadfield has never punched a moon landing denier...
9:30 I couldn't resist checking the values. Using
G = 6.674×10⁻¹¹ m³kg⁻¹s⁻² and M = 5.972×10²⁴ kg and
r = 6357 km + 420 km = 6.777×10⁶ m
we get that
v = √( GM/r )
= √( (6.674×10⁻¹¹)(5.972×10²⁴)/(6.777×10⁶) m²s⁻² )
= √( 5.881 × 10⁷ m²/s² )
= 7669 m/s
Yeah, that's 8 km/s, just like Chris Hadfield said 🤩
Well done
You could also use GM/R2 = g = 9.8 m/s2
You’d think he’s been there himself. 😄
@@eduardosuela7291 It only works if you calculate it on the surface of Earth. You need to multiply g by R^2/(R+r)^2
It's like you need to know what you're talking about to become an astronaut :P
How do you make superscript/subscript in YT comments? 🤔
Matt AND Chris Hadfield, jeez that put a smile on my face. Regarding orbital mechanics, it always makes more sense to me to think of velocity as relative velocity (which of course it is).
Hmm but for rotational velocity thats not true is it?
@@jeffreylebowski4927 Even rotational velocity is relative. You always need a reference frame.
If you have 2 weights connected with a spring, and you rotate them in empty space, you can tell their rotational velocity and angular speed by looking at how far the spring gets streched by the centripital force, even if your reference frame is rotating around with them. Similarly an orbiting body around earth has to have a certain velocity to stay in orbit and it is clear, that it is the lighter orbiting body moving around the earth and not the earth moving around the satellite... (theyre both moving around their shared center of mass but whatever), so if you can definitivly tell who is moving and how fast, how is it relative?
@@jeffreylebowski4927 in a frame of reference that is stationary with respect to the spinning springs, it looks like their inertia is driving them outwards. In a rotating reference frame, it looks like there's a force pushing them outwards. Both are correct, depending on your point of view. Rotation is just normal movement which is constantly changing. The only thing all observers agree on is the speed of light, which is where the theory of relativity kicks in, of course.
Put more bluntly, there is no absolute frame of reference, a 'universal' stationary reference frame can not exist (this can be shown experimentally). Hence, velocity is always relative.
6:50
Matt: "Get rid of an m from both sides, so I'm afraid your mass now doesn't matter..."
Chris: **shrug and smirk**
God damn he's cool
Edit: Also, I appreciate his landmark numbers are coffee-centric: 9:18 "The time it takes to drink a cup of coffee" 11:47 "Our target was about the size of a coffee saucer"
It does matter if you have to fuel the shuttle. You can’t get away from the fact that they lose mass at each burn and a more massive shuttle is harder to change velocity since it has a certain amount of momentum. It won’t change the target velocity at the radius but it does matter what the mass of the shuttle is.
I appreciate how youre helping to spread the concept of landmark numbers 😉
Skye Blue I get that. But they have to use acceleration to achieve a change in velocity and orbital distance. Just thought it was interesting how the high school level physics is being presented by the big guns. I wished they would have gone into the trickier stuff.
Polynomial
Factoring...
ruclips.net/video/1dhTGpc0mHQ/видео.html
Hearing Chris Hadfield describe a portion of docking procedures as brute forcing it makes me feel better about how many kerbals I've trapped in orbit in KSP.
me too. I've gotten close but never succeeded at the rescue mission scenario :-(
Docking in KSP can be (as soon as you are within a few hundred meters and at a relative stop) done very easily. On the first spacecraft, select "control from here" on the port you want to dock to, set the port you want to dock to on the second spacecraft as the target, and set SAS into point at target mode. On the second spacecraft (which must have RCS or thrust inline with the docking port), do the same, then gently thrust in to dock.
@@zuthalsoraniz6764 thank
Zuthal Soranizc, yes, that’s all well and good, but in career mode docks aren’t available until after the first rescue mission. So needless to say my first few “dockings” were really just incredibly difficult near-identical orbit encounters.
Later to save one crew on a large ship with no dock or electricity (forgot to add solar panels), I had to bring a rescue vessel directly beside, attach an engineering strut to hold them together, then EVA to attach some solar panels.
It sure was nice after that when I finally unlocked docking ports!
I've played enough Kerbal Space Program to know where this is going
no realism overhaul, no balls
I've played enough Kerbal Space Program to know that I would crash and burn in Hadfield's shoes.
@@lazarus190 Well, crashing and burning is most of the point of KSP.
Kraken?
@@mastershooter64 well, is it enough to launched a probe to titan and came back ?
Chris really does come across like a great guy. His son also runs a very high quality RUclips channel so he’s probably a great dad too! (The channel is called Rare Earth for those who don’t know.)
Thank you very very much.
Woah! Thanks for revealing that fun fact
Hilarious
Yeah, I definitely also recommend checking out Rare Earth on RUclips. Excellent storytelling to be found there.
Like others here, I cannot recommend Rare Earth with Evan Hadfield too highly. It is without question one of the very best documentary channels out there.
I love that Chris makes simple analogies to make it easier for plebs like me to actually understand this space stuff.
Simplification is the most important indication of understanding
I'm glad Chris is still making content and getting recognized, he's one of the coolest and most interesting people both on or off the planet. Just a nice, sincere, and humble guy too. An absolute pleasure to watch! Hope you can convince him to make more collabs lmao
You can tell he drinks a lot of coffee from all his analogies! Time it takes to drink a cup of coffee, target the size of a coffee saucer, the man is loaded up on caffeine
Plus he's told these stories so many times to us grounders, he knows how to relate!
Hadfield came up with the original idea for the zero-gravity coffee cup which was then developed by Lavazza.
ruclips.net/video/dWuEVSCw8B8/видео.html
Polynomial
Factoring...
ruclips.net/video/1dhTGpc0mHQ/видео.html
Assume a spherical Chris Hadfield in vacuum …
Incredible joke, I love it.
don't forget he'd be frictionless too
@@PaulMansfield If he's in a vacuum, could there exist any type of friction?
@@manuelbonet Frame dragging
Manuel Bonet Some astronauts are known to have had a little friction with each other...
Docking gets kind of intuitive after couple 100s of hours in KSP. Atough my "proximity operations" usually start 2km out
Those are rookie numbers. Gotta get that 0m intercept!
@@HaraldSangvik Ah yes I see you're a man of culture as well
@@HaraldSangvik I remember the first time i got a 0m intercept. Let's say that i didn't brake on time and the impact destroyed the target and took my engine.
I managed to land the surviving kerbals by deorbiting using rcs thrusters.
@@eyondev proper kerbal. Love it.
Francesco Gentile hat tip 👍
2:10 Classic Parker SQUARED, almost forgot the exponent
It's a joy that Matt got to meet the legendary Canadian Chris Hadfield.
I'm also glad the Canadian name on the Canadarm is visible.
I was introduced to Matt on Tom Scott's channel, and I was introduced to Tom Scott because of an interview he had with Chris Hadfield. The cycle is complete.
Awesome that you got the legendary Chris Hadfield to make it onto your youtube channel. Classic physics problem explain by two great explainers. I loved the end about docking because it gave some insight onto what actually happens on the ships.
The speeding up to change orbit is similar to going up a hill on earth. To get a vehicle higher you need to speed up but when you reach the top you will have slowed down due to that kinetic energy becoming potential energy.
Best explanation ever.
With the sunglasses and jacket, if he'd been any cooler there would have been a cascade effect that would have plunged the world into an ice age
Coolest guy on - or at least near - Earth.
This feels like a symphony of presentation. You two are playing off each other wonderfully well.
Actually, it’s just Chris playing amazingly off you. But it’s an exceptional video. ❤️
I love how he let you math math math away, and then wuuuuurp! Rockets!
They did great
Love the physics 1 board, but love even more the introduction to the concept of "prox ops", helps me explain and understand a simple intuitive everyday concept more clearly.
Good thing Chris was there to fact check, or we might have ended up in a Parker Orbit :D
Excellent video, I really enjoyed that. Thanks Matt!!
Chris Hadfield is a rock star; not only did he do what we all wish we could do, but he’s so relaxed and humble about it it makes you respect him even more. Plus, it’s actually great seeing him chat with a good teacher like Matt 🙂
I see Chris and Matt, and I watch. It could be 29 hours talking about fences, and I’d still watch it.
💩
Nice, wasn't expecting this combination of coolness (4:23 to see Chris throwing NASA gang signs)
Hah, now I'm curious, are those spaceman gang signs in general or NASA specifically?
When is the next best moments vid commin up brother 🤗😊
it was in this positionerino agadmatorino.India won by the way
maths + chess + kriparrians. best combination
@@vallov4188 He was thinking about the triangles. Sometimes it's easier to use your hands to "see" some relations. I bet you that at least 9 out of 10 times you stand and watch a university level physics exam, you'll see most of the students doing signs like those (specially one with their thumb, index, and middle finger - it's the 'right-hand rule' -).
listening to Chris talk about this stuff was incredible
Matt needs to learn Hohman Transfer Orbits, they're not the only way of adjusting orbits but it gives you a good idea of how it works.
9:07
Mat. "and how long does it take between when you launch and when you get to that orbit?"
Chris. "The rockets have to burn and accelerate you up to the right speed and the right angle, It takes somewhere just a little less than 9 minutes. From sitting here in Florida on the pad laying on your back, to the engine shutting off and being there weightless in orbit"
Shame this wasn't asked slightly earlier, the tie up in time would have been awesome. Could have ended it with "Takes as much time as it's taken to watch this video up to ... *NOW* "
Meanwhile, similar timescale.....landing on Mars. Just watched season 1 of Away on Netflix. Good stuff, that landing timetable.
Really loved this one! I studied orbital mechanics in school, and now in my work I talk about the possibilities for rendezvous and proximity operations (RPO) all the time. It can be used for docking at the space station, or it might soon be used for cleaning up space junk.
If the space junk doesn’t permanently ground us before then.
For those that go to Orlando-don't look for the Kennedy Space Center-you have to drive to the coast...Cape Canaveral.
At least an hour away, with almost nothing but swamp between Orlando and the coast. But I guess if the cruise ships can sail out of Orlando (seriously, they say that in their commercials) then I guess Matt can claim Kenedy is in Orlando, too.
@@AedarinOfMinecraft don't forget.. The Orlando tourism folks include any beach that they've been to as part of "Orlando Beaches" including Cocoa Beach and Clearwater Beach..
When you're coming from the UK, you start by getting on a course that will take you to Orlando, then when you get close, it's prox ops and you stop worrying about cities and you just move towards the space center.
@@AedarinOfMinecraft Disney busses are painted like ships shuttling people from the ships to the parks.
@@tentenbits The only legit one is Disney Blizzard beach!
wow... hearing Chris describe docking exactly how i experienced it in SimpleRockets 2 is surreal, doing calculated burns to get close to target, understanding how falling around the earth completely changes predictions of how it would move if it were linear paths, and then prox ops, trying to fly it manually and brute force the unconventional mechanics the rest of the way up to lining up on a saucer dish sized target... utterly perfect description of the brain processes required to fly in space
*Math is the best tool to describe everything! Physics, chemistry,...everything!* :)
Yeah! True :o
It's general enough to be applicable to virtually anything, and specific enough to still be meaningful for lots of things. Truly the best of languages.
and spreadsheets
What about gender studies?
Well, problems arise when we ty to apply maths to qualitative entities, like happiness.
I mean, statistics is a great help, but it's still murky territory.
The most straightforward and intuitive explanation of basic orbital math I've ever seen. Well done Matt and Chris!
My first thought on seeing the thumbnail and "I'm in Orlando" intro was "Well of course they're disregarding physical distancing protocol... They're in Florida."
(Yes, I saw the note that this was recorded in the before time, the long-long ago of February.)
One of the most revealing videos ever, for me personally. I had a vague idea of how docking is happening, but wow, you accelerate and the result is you're slowing down!! Oh boy... Huge thanks Matt and Chris !!
Everyone already knew he was cool after he sang Space Oddity...in Space
In my education for becoming a math teacher I created an exercise for students to derive these equations. It worked it's way up to determining the velocity increase needed for a hohmann transfer to Mars and determine at which day to launch so that Mars would be at the correct spot when you arrive there. It's the perfect way to connect differential calculus to physics.
I appreciate the framing to include the Canadarm
That was very much on purpose yes! One of the videos upcoming with Chris and Lucie Green has a whole section on it!
What a great ambassador Chris Haddfield is for space science and a great inspiration for any youngsters thinking looking for a career in it.
Chris Hadfield, an absolute legend.
I live close enough to KSC that I was hoping to see a beautiful Atlas IV night launch early this morning... They did a "hot-fire abort" instead. Meaning that they got all the way to T-minus 3 seconds and ignition but the engines didn't start and the rocket stayed on the launchpad.
At least they didn't pull a Kerbal and have the second stage fire while still connected to the first stage.
You have no idea how fast I clicked when I saw this video. Matt & Chris Hadfield, this is the best anime crossover event in history!
I’m a senior in highschool and I’ve never been interested in math for longer than a few seconds but I managed to be captivated this entire video.
Shoutout to everyone who learned about orbits and docking in KSP
Matt Parker, Chris Hadfield, Kennedy Space Centre, Space travel talk and my favourite type of maths??
This is the perfect formula for my favourite video :)
Same here
12:55 that beautiful moment when Matt's brain can't quite envision the real world execution of the maths he can work out all day long without out breaking a sweat. Not a dig either, but rather an observation about application vs. theoretical in any field, echoed by what Cmdr. Hadfield said earlier in the video about how in his job they don't do the maths in public but instead deal with the practicalities in real time. Outstanding video, made maths fun with two charming presenters.
This and the version with Chris describing launch and ascent are marvellous.
Really needed a shout-out to the ‘computers’ who really made space flight possible and survivable in the 50’s and 60’s.
Much better than my structural engineering prof who would fill the chalk board and then announce “it can be shown” and write down the answer. We were expected to remember the derivations in our exams!
After playing KSP with RSS and Principia. "I've landed a probe on the surface on the surface of Enceladus."
After watching this video. "V is equal to what?"
This is the most compelling demonstration of basic trigonometry I have seen
"bit of a perfectionist." Matt, the Parker Square may have something to say about that.
well obviously he's not a *whole* perfectionist.
Matt Parker and Chris Hadfield in one video about orbital mechanics(very basic math but the part from where he talks about docking was 'out of the world')!! Clicked instantly!!
it's always kind of blown my mind that orbit is just falling towards the ground without ever hitting it
It's falling *with style*
@@discretelycontinuous2059 😁😁
When firing the rockets in orbit, it depends on if you do it prograde or retrograde. I learned this while playing Kerbal Space Program, introduced to me by Scott Manley
Ya, Hadfield must know that Matt is going for a
Matt: I am in Orlando at Kennedy Space Center.
Me: No, you are at Cape Canaveral. Orlando isn't that wide of a city. 😹
I can't wait to go to London and see the White Cliffs of Dover.
I bet you're fun at parties
At the rate Disney is expanding it will all be subsumed in the near future.
This is by far my most favourite of your videos. Thank you so much Mr Hatfield and Mr Parker.
Tip: if you don't want to bother finding out the values of the gravitational constant G and Earth's mass M separately, you can instead use G*M = 9.8 * (Earth_radius)^2 (use SI units!).
If what units you're using matters, you're not using units correctly.
@@JohnDoe-nq4du he probably mentioned it because many people don't care about compatibility so per example they use m/s^2 for G, but miles for r.
@@JohnDoe-nq4du I would say that you are correct, but also that if you are not using SI units, you are not using units correctly. Also, I don't think it's wise to measure gravitational acceleration in feet or miles by square second (let's say).
Or work it out it fff units.
g is approx 71 Giga-furlong per fortnight^2
I have two degrees in physics, I taught physics and astronomy, yet I still find these lessons fascinating.
Orbital mechanics. The place where “slow down. He’s getting away from us.” Makes any sense at all
Yes, indeed... *"because Math isn't chemistry."* You have a problem and in fact an enormous problem with "friction"(meaning you're interacting with the massive amount of energy generated from Sun interfering with our pristine math.) In other words upon achieving said "orbit"(hooray, both of us are falling together!) you soon discover that at this level of specificity (incradibly high velocities) you comparative "rates of falling" are hardly the same. In other words for any of this math to in fact make "mechanical sense" you need a constant that would also exist in similar domain. Not a "space person" but back of the envelope I would argue just use the Moon as your constant and "triangulate" (two separate maths now) what is an all too "need to fixed relative position."
In the alternative you can just *GO* to the Moon and *LAND* there of course..
Polynomial
Factoring..
ruclips.net/video/1dhTGpc0mHQ/видео.html
That must've been an absolute honor. I'm a big fan of Chris Hadfield and also of his son.
Turns out Chris Hadfield is great at explaining maths. Should be a stand-up
He does a MasterClass on the maths and physics of space flight
Awesome video, Chris is great! The discussion of orbital mechanics during docking really beings back my experiences in Kerbal Space Program over the years... You really have to keep in mind what your maneuvers will do to your orbit relative to your target and remember to be compensating for the drift that causes, even at short range you'll find yourself slowly circling around the target station or vessel if you hang out nearby too long without getting that solid connection made!
Indeed fascinating, that the necessary speed only depends on the radius, not on the characteristics of the object you want to fly around (as long as it fits in there without scratching the atmosphere or smacking into too much space debris ;) ).
Aerodynamic drag is actually a factor even for ISS, because of how huge its solar arrays are. So while shape and size of the ship/station doesn't change how fast you need to be going, it is a factor in how frequently you'll need to fire up the engines to stay up there.
It also depends on the mass of the object you want to orbit.
@@oisyn the speed does not depend on the mass. How much you need to burn to get to that speed does, but that's another topic
@@Daniel-yy3ty Of course it does. If the body you want to orbit is heavier, you need to increase the speed to compensate for the extra gravitational pull. In other words, a 7000km (radial) orbit around earth requires a higher speed than a 7000km orbit around the moon.
@@oisyn oh, that mass. never mind then :D
Go faster, to go higher, to go slower...
You guys explained it 4 times, my head can't comprehend.
"You don't want your speed to slow down. I guess that's the definition of being in orbit"
In a circular orbit. It's the definition of being in a circular orbit.
Regarding the orbital mechanics at 12:40 ... I like to use a circle track as a good analogy (NASCAR or speed skating, or whatever works for you)
When you speed up in orbit, you increase the size of your circle track. So even though you are going faster, the distance to complete a lap is further so it ends up taking longer to complete a lap. So, if you want to catch up with someone orbiting far far ahead of you, the easiest way is to actually slow down, thus decreasing your circle size. With a bit of proper calculations, you can slow down enough to meet perfectly up with them on the next go-around (just don't slow down by too much, or you'll crash into Earth, which is not ideal).
Once you're within spitting range (proximity operations, as Chris Hatfield calls it), then you're going to be speeding up and slowing down in *tiny* increments, and too quickly for the velocity changes to have any impact on your circle track. So that's when you can just "brute-force" yourselves together.
It must be an interesting feeling seeing something you used/worked with, exhibited in a museum.
me: * cries in gameboy *
My favourite orbital mechanics fact that wasn't mentioned: orbital period near the surface of a body is a function of density. Because the earth and moon are both rocky bodies (and therefore similar density), they both take about 90 minutes per orbit. All other rocky bodies will have similar orbital periods, regardless of size.
That doesn't seem quite right. Mass is proportional to r³ (assuming fixed density), and if r[body] ≈ r[orbit] then we get v² = kr³/r = kr², which means v ≈ r.
Oh, but you're talking about period! So that's circumference over speed, both of which are proportional to radius, so that cancels out and we're left with just the constants. Neat.
I was a squealing fangirl when Hadfield showed up 😅
Same here, and I'm a rather large framed 47 year old man. :D
Me toooo...😅😅
As someone who did too much math in Kerbal Space program (with a mod called KerbalOS mod actually) the math checks out. The headaches comes when the orbit isn't a 2-body problem with a non-perfect circular orbit. Orbital eccentricity makes everything way harder.
A math nerd and astronaut walk into NASA..... Start of a beautiful friendship, or a great joke!
3:05 A constant radius should the the exception to the rule. Any small imbalance of force through the radius would cause an elliptic orbit with some eccentricity.
2:56 This is why Matt specified, "We're now going to look at you A VERY SMALL MOMENT OF TIME IN THE FUTURE". After a sufficiently small difference in time, the radius doesn't change enough to have a significant effect on V (delta V is insignificant, and can be treated as 0).
@@TheDannyHamilton That's not the point. The point is that he has restrained his calculation to only circular orbits. If you want to be able to do any kind of maneuvering in orbit, you need to use an elliptical orbital model because any component of thrust colinear with center of the earth will cause eccentricity.
@@timharig If you're in a perfectly circular orbit, any component of thrust parallel to either your current motion or your current radius will add eccentricity. It's only a purely horizontal sideways thrust that will keep you moving at orbital speed for your current altitude and in a horizontal direction.
@@rmsgrey Hence the need for a elliptic orbital model. Because any time you add thrust, what you are really doing is changing which ellipse your orbit is following. (Or in the extreme case, another conic section.)
Ground Control to Major Tom!
Ground Control to Major Tom!
Matt Parker got the Stand Up Math vids on!
Chris Hadfield meanwhile really sang this song!
h8=N+!
@@Jivvi Yes!
Full study:
wKg7 Rf3 Be4 Pe5 f6 g5 - bKh5 Ra7 Rh3 Ng3 Pf7 g6; White to move and draw
Siegfried Hornecker, Probleemblad 2005
Collaboration I didn't know I needed , what a legend
That vector notation is giving me anxiety
in the netherlands we draw a line above the vector instead of under 🤔
@@valentijnraw everywhere I've ever seen, a vector or is in bold or have an right pointing arrow on top of it. Because of my engineering background, i really fancy the arrow.
Also, the multiplication dot at the bottom instead of the middle.
I've used both
I'm almost certain Matt is trolling.
Man I am really thankful to Kerbal Space Program for teaching me all this stuff completely intuitively so now I can understand the math and all the technical thinking behind it. Having an empyrical understanding of orbital mechanic would have been pretty much impossible without a piece of software that lets you tinker around with virtual rockets.
Beautiful video.
0:24 "These rockets behind me were originally developed to put things in orbit" - *confused Mercury Redstone sounds*
More like "put chunks of plutonium and/or hydrogen into suborbital ballistic trajectories"
@@mastershooter64 Like most early rockets, they're ballistic nuclear weapon launch vehicles, repurposed to launch spacecraft instead.
@@GeorgeFoot yea i know that, i forget they used hydrogen in thermonuclear warheads(hydrogen bombs) its in the name lol
Just - WOW! The stories and experiences that he can convey are incredible.
Chris Hadfield: "Docking with a space station is not automatic. There is no 'Standard orbit Mr. Sulu.'" SpaceX: "Hold my beer..."
The shuttle's AP-101 computers had much more in common with the Apollo guidance computer than most people realize. The technology between the two is really only about 10 years, and it took five of them (four in sync and one for error checking) to get the needed reliability and redundancy. SpaceX was able to start from scratch using computer technology and interface improvements at least 50 years ahead of the shuttle. And even now there is a significant amount of pre-processing that is done on the ground to ensure success. Mr. Sulu's job isn't in jeopardy quite yet.
Soyuz has been doing that for a while
@@corwinchristensen260 True that said it is not inconceivable that Starfleet could have standard pre-defined orbits and such for much the same reason why we have standard flight levels using a standard altimeter setting in aviation. When you start having to manage large numbers of craft all while making sure to keep them a safe distance from each other such standardization becomes invaluable for making sure everyone is working on the same page. We already did the same for shipping and later aviation when they became popular so it's not exactly surprising a society that made heavy use of spaceflight would do likewise.
Seraphina, not to mention the way different types of satellites have various categories of standard orbits.
@@Keithustus Indeed just would be even more important when most of the craft are manned.
Respectfully, what a great honour for Mr. Parker to meet with Commander Hadfield.
Kennedy space center isnt in orlando. its like an hour east.
I love how you proved that the mass of the orbiting object didn't matter. You showed mathematically what Galileo said 400 years ago -- that all objects, no matter what their mass, will fall with the same acceleration. Awesome!
This is one of the assumption that went into Newton's equations. Therefore, it's kind of silly to say that Newton's equations prove that two objects follow the same trajectory in a gravitational field.
8:16 “If you were to hold a globe, and bring your eyeball down to maybe like a thumb-width, that’s how far we were from the surface”
wow Hadfield uses intuition so much he seems to have forgotten both metric AND imperial lol 😂
Sanjit Raman the best demonstration I've seen of this was I think from Dr Becky using a globe and some lego blocks.
crt33 please share! :)
The display for Atlantis is AWESOME. It's worth the trip all by itself. When they revealed it, it gave me chills.
Just a practical question: All the equations I've seen in school calculate a circular orbit, but no satellites do that. What is a *practical* relation between the circle and ellipsoid orbits, in terms of speed and energy?
Look up "Vis viva equation". I think the second most useful equation in space science after Tsiolkovski's rocket equation.
If you average the apoapsis with the periapsis, you end up with a value known as the semimajor axis (SMA or simply lower-case a). Ignoring any atmospheric drag presented from an insufficient periapsis, and any gravitational inputs from additional bodies such as the moon, all bodies orbiting with the same SMA will have the same average velocity, even if the eccentricity of those orbits varies wildly. The ground-referenced speed of those orbiting bodies will change depending on their current altitudes, but they will all average out to be traveling at the same speed and orbital period.
TLDR: a circle is just an averaged ellipsoid, and we lack the technology to orbit in (or even freehandedly draw) perfect circles.
Every geosynchronous orbit is circular, and I'm pretty sure that's where most of our satellites live (ignoring Starlink etc). Also the GPS satellite orbits are only about 2% off circular, though they aren't geosynchronous.
It is true that they can only approximate circular orbits, but on the other hand there are a lot of satellites in approximately circular orbits.
@@patheddles4004 Tundra orbit is geosynchronous and definitely not circular.
@@patheddles4004 There are more satellites in low earth orbits than in geosynchronous ones, but other than that, you are right. Most satellites have approximately circular orbits.
I was confused about the higher orbital and slowing down thing until I remembered mechanical energy and total conservation of energy. Thank goodness!!!
This man has such an amazing moustache, I envy him
This man has such an epic career and profession, I envy him.
@@KoryFae that too
but the stache man
reminded me of Dr. Robotnik
3:36 I'm not sure if I understood it correctly but it you said "you're getting lower, you're slowing down" then that's incorrect. Neglecting the atmosphere, you are entering a lower and thereby faster Orbit. Thus, you speed up. This effect can be seen in very elliptical orbits. As you leave Apogee, you are getting closer to earth(thus getting lower) and speeding up til you reach Perigee, the lowest and fastest point in an Orbit
3:05 "That's kind of the trick to staying in orbit, right?"
"Uh, yeah, basically" (translation: no, not really, but let's just go with it)
The real trick is to fall and miss the Earth
@@HagenvonEitzen Always falling but never getting closer.
kerbal space program taught me everything I need it to know about orbital mechanics also I loved that you could see that the equations could be extended to elliptical orbits :)
"these rockets behind me were designed to put things in orbit" *is standing in front of a mercury Redstone rocket*
Good amount of those rockets were designed to put something in the Soviet Union.
@@gladiatorbmx yes we all know that the space race was a thinly veiled nuclear arms program
Quick, somebody get Scott Manley
I think he meant these specific rockets in the background
@@gladiatorbmx ... and ultimately put the Soviet Union in orbit, duh
The two biggest inspirations in my life, in one video! Exciting.
Chris Hadfield’s birthday is tomorrow- August 29th- the same as mine.
Nice
Happy birthday!
Happy early Birthday, u and Chris are out of this world
Happy birthday to him (From the UK)
The same as mine. Happy birthday
One other formula that is quite interesting:
if the circular orbit velocity, v at radius r is given by v^2 = GM(1/r),
then to reach escape velocity starting at the same r is given by v^2 = GM(2/r)
i.e. if you are in a circular orbit around any object. if you can increase your speed by a factor of SQRT(2) - i.e. increasing it by roughly 41%, then you will completely escape from orbit.
All the time Chris was like : *Yep*
Its funny though
Was a little concerned by that at first actually, as if Hadfield was just a stick controller who wasn’t actually a math guy. (As if).
Matt AND Chris Hadfield !!!
how do people thumbs down such a pair?!
What concerns me is they're not standing 1 bus-length apart.
What amazes me is why Americans don't use "0.02 football fields" as the social distance separation :-)
@@Ryan_Thompson I saw a photo of a sign in Florida telling people to stay 1 adult alligator apart.
@@John73John Ha! Love it.
And the alligator ate both men.....
I jumped at the hand shake
Astronauts are literally the only people I respect and adore whole heartedly without question. And Chris is definitely a huge part of that for me and so many other people like me. So great job Matt!
Mathematicians be like- " I'm gonna draw myself as a dot here"
Edit- thanks for the likes, I have never gotten this many likes before
it's more of a Physics approach, but works in Maths as well. Everything boils down to the centre of mass in the end
It's a joke, man
We assume a point mathematician.
We will also assume the mathematician is infinitely dense
@@Sarika428 -im a woman-
What a man! I wish I can do this once in my life although it is highly improbable. Thanks for the video Matt, it was great listening to Mr. Hadfield talking about his experience.