Hey it's me Destin, welcome back to Smarter Every Day. Most people know that if you're gonna go to the International Space Station you first get on this rocket in Russia called the Soyuz. You strap yourself in, you launch from Baikonur and you go straight up to the space station, you pop open the hatch and then you high-five all your astronaut buddies, right? But there's a lot more to it if you think about it. There's actually orbital mechanics and physics that are all figured out on the ground before they leave. So today on Smarter Every Day we're gonna talk about rocket science, and it's really not that hard, I promise. US astronaut Scott Kelly, and Russian cosmonaut Mikhail Korniyenko are about to go to the International Space Station for an entire year. That's a really big deal. But before we talk about the orbital mechanics think about this. Astronauts are just people, like me, like you. What would you be thinking about if you were strapped into that rocket, knowing you're gonna leave warm showers for an entire year. How cool would it be to actually get inside this Russian rocket and have just a normal person to person conversation with a guy that's about to do this? Even though his launch window is getting closer and closer, and his time on Earth is more and more precious at this point, Scott Kelly was gracious enough to volunteer some of his free time to just hang out with us in the Soyuz capsule and tell us what he's about to do. This is astronaut Scott Kelly. - Hi. - Scott's about to do something no American has ever done, he's about to ride one of these, which is a Soyuz capsule, up to the International Space Station for how long? - I'll be there about a year. I'll launch in March of 2015, next March, this year, and land sometime in March of the following year, so it'll be almost a year. - Alright so there's a whole regime of different science experiments that's gonna happen because of this. The main goal is to get ready for Mars, a long duration mission, right? - Yep, that's correct. You know NASA's ultimate goal is one day to put people on Mars so there's a lot we need to still learn about that. Some of it has to do with how the space environment affects the human body for long periods of time, particularly with the growths of bone loss, muscle loss, effects of radiation on our genetics, our vision, we have problems with vision with crew members during long duration space flight. Our immune system, vestibular system, so that's kind of the human part of it, and there's also the hardware part of it. You know travelling that far away from Earth is a, you know represents a challenge with regards to how we design our life support systems, you know how we produce oxygen, produce water, and you know those kind of things, electricity to keep us alive in space for long periods of time. - It's like camping for a year right? - Yeah, you know this flight will be camping for a year. Even though you're in space you're still 250 miles above the Earth, although you're going very fast at 17,500 miles per hour, but it still is a place that we can get resupplied fairly frequently, but when you're going to Mars you can't, so.. - Are you gonna simulate any of that? Are you gonna, you know, change your underwear less frequently or anything weird like that? [laugh] - [laugh] Ahh.. I wasn't planning on it. - [laugh] These are important issues we need to know man. - Yeah, yeah.. But ah, are we simulating anything about.. We're doing a lot of science that would relate to living in space for longer periods of time. As far as particular simulation, I'm gonna, you know personally I'm gonna try to imagine, OK it's six months, you know, we might be showing up at Mars and then I'd spend a year on the surface and it'd take me.. - Because for you, this is different for you than any other astronaut. Obviously your twin brother Mark's on the ground, he's, you know, he's taking all kinds of data as you're doing that up there, but for you, I have looked at the duration of your space flights. If you graph them, you're gradually getting longer and longer, so I mean if you project that graph up, that's like a space, or a Mars trip type duration. - Yeah it was interesting, I mentioned that in a public affairs event, how my first flight was 8 days, second flight 13, third flight 159. My fourth flight will be around a year. And if you tried to draw a curve it's like a second order polynomial, and if I was to fly a fifth flight, you know, and flying along. - That puts you on Mars, wouldn't it. - It puts me at five years, over five years in space, so easily go to Mars. - That's awesome. - Which probably means I'm not gonna fly in space again right? - No I saw where you tweeted that. When you're actually flying here, you're gonna be under intense acceleration, so how the heck do you push that button right there for example? - The guy in this seat can kind of reach, but the guy in the center seat has a stick, he can push the buttons. - So he just grabs a stick and he sticks it up there. - Yeah, it's a fancy stick but it's a stick. And I can control some of his valves over here, I can reach them better from there than he can. - So you actually control docking and things like that from here? - Yeah the Soyuz commander can.. The Soyuz docks automatically generally, but sometimes you have to downmode to a manual docking and you control it from here. - OK that was pretty awesome, however we still don't know how the Soyuz gets up to the station. To figure this out let's go talk to Reid Wiseman. His expedition recently set the record for most research done in a single week on orbit. You just recently did this. - I did this. - OK - I did this May 29. - Is it awesome? - Oh it's awesome. - Alright, so what happens once you get to space? OK people know the rocket, and people know space station. People have no idea what happens in between. - There is a little bit that happens in between. - OK - So the ride from ground to space, that's nine and a half minutes, and that's on a really powerful rocket, everybody's seen it, it's filled with fuel, a lot of fire, you go up, and at the end of that ride you're going about 17,000 miles an hour. - OK. - OK and from there though, you have to rendezvous with the International Space Station, and that's going just a little bit faster. - And that's what I want to talk about. - Let's talk about it. - OK. I think what a lot of people think is that the rocket just gradually takes you up to the space station in this spiral orbit, and that's not what happens at all. - You know what I used to think? - What's that? - I used to think the rocket just launched straight up to the space station. - Yeah, I get it. - I never thought that it actually tracks down range. - So what is the moment where you're like, "Holy cow I'm in space," when does that happen? - The moment, that moment is very clear. It's exactly when your third stage cuts off, so that's nine and a half minutes in, and you're no longer under powered flight, and your booster falls away, and you really, you actually feel like you're floating up because you're still strapped in your seat. They're gonna put you up at a fairly safe altitude where you're outside the atmosphere and the rocket's not gonna fall back down. It's not gonna have a lot of drag on it so it'll just stay up there. And then from there, we're gonna do a series of burns, and in the Soyuz we do seven burns. OK, but the first two are just gonna be a straight up Hohmann Transfer. - OK gotcha. Let me explain that. A Hohmann Transfer, make sure I get this right, a Hohmann Transfer is like if you're in a circular orbit, and you want to go to a larger or smaller circular orbit, you draw an ellipse between the two circles right? - That's right. You're gonna do a burn on one side, and then 45 minutes later for us, you're gonna do another burn because you're gonna be on the other side of the planet. It's a little less than 45 minutes. - Gotcha, OK. - But then that'll perfectly, that'll turn one circular orbit into another circular orbit that's either a little bigger or smaller. - Got it. Two burns, Hohmann Transfer. Awesome. So then the second Maneuver... It's actually a little trick We don't know on that booster We don't know exactly where it's going to insert us into orbit So we could be a little high, a little low, A little fast, or a little slow. -Why is that? Is it because every rocket isn't the same? - Every Rocket is a little bit differrent These next two burns are just gonna correct for our dispersion errors. And now we're pha.. what we call phasing with the space station. So we're gonna stay in this phasing orbit until the space station is kind of where it needs to be. - Oh, OK I got it. If you are closer to the Earth you're actually orbiting the Earth quicker right? - That's correct. - OK so what is it, on station it's every 90 minutes you go around the Earth? - Once every 90 minutes. So when you're a little bit lower it's once every 86 minutes, you know it's a little bit faster. - OK so that's the purpose of the phasing orbit then. - Catch up with the space station. - OK, got it. So that's our timing. - That's our timing. - So now we're four burns in. - OK - But now.. - So we've done our Hohmann Transfer.. - We've done our Hohmann Transfer to build our orbit up, we've done our next two burns to correct for any sort of dispersion on ascent.. - Now we're on the perfect phasing orbit. - We're perfectly set, perfectly circular orbit if that's where we wanna be, and now we're just waiting, and when the space station is at the exact right spot we're gonna do one more Hohmann Transfer. Two burns. And it would actually send us out in front of the space station. So what we'll do is we wait, and right when we get in front of the space station we turn the rocket around and we do a third burn now, and it sets us perfectly up in front of the space station. - So you do a U-turn in space? - You do a U-turn in space. And you actually see it. You watch the Earth go all the way by, you go backwards, you hit the brakes just a tiny bit, then you flip your space ship back around pointed at the space station, and now we're sitting right in front of the ISS and we're just waiting and then we're gonna go real, real slow. Proximity operations and we're flying it just just like an airplane, and we go in and dock. - Sweet. OK so it's just X, Y, Z, roll, pitch, yaw at that point. - Exactly. - That's fantastic. How long does it take to actually dock to the space station? - It takes about a half an hour. From the time you get to prox ops, we're gonna go really really slow and it takes about a half an hour to get that docking completed. - OK is it.. - You could do it much quicker but I mean when you have two big pieces of metal that are going 17.500 miles an hour, you want to make sure they touch each other pretty gently. - Let's summarize.... The launch gets you into the insertion orbit where you do a Hohmann Transfer to get up a bit higher. You do some clean up burns to get into the perfect phasing orbit where you catch up with the ISS because you're going around the Earth faster. You chill right here until the time is right and then you do two burns which puts you out in front of the ISS. A FLIP and a BRAKING BURN then brings you in for docking and there you go. You now understand some rocket science. [music] So seriously, my goal for this video was to more than double the amount of followers on Instagram for Scott Kelly and send a bunch of people to his Twitter account. He's like a living science experiment on the International Space Station. So please go check those out, I'll leave links in the video description. I would greatly appreciate that. I'm Destin, you're getting Smarter Every Day. Have a good one. OK we're in the ISS. This is where you dock? - Yeah so this is the Russian segment and a much higher fidelity mock up in Russia but there's a module that comes out of the top of the space station here called MRM2. My Soyuz will dock to that. The other Soyuzes are docked in other parts of the Russian segment. - Thank you very much sir, I appreciate your time. - You bet. - Have a good one. Bye.
Can we take a quick second to thank /u/mrpennywhistle for not letting the gaining popularity of his videos obstruct the quality of them. They seem to keep getting better! I can't wait for all of these new space videos on his YouTube channel.
I play Kerbal Space Program, so... you know... If you have any questions, you can ask me. I'm pretty good. Unless you want the correct answer (snob), in which case you can ask one of these "smart" people.
Hang on, I'm pretty sure I understand orbital mechanics, something doesn't seem right here. If Soyuz is in a lower orbit, it can't be moving slower but orbiting faster. Its orbital velocity is faster, and its orbital period is faster. It's faster all around.
For the ISS at 400km, oribital velocity is 17,157 mph, and period is 92 min. For an approaching Soyuz at say 375km, velocity is 17,179 mph and a 91 min period. Both are faster. Not sure what the purpose of wording it that way is...
Just a small correction so people aren't accidentally walking away with misinformation...The ISS isn't moving faster than the soyuz when the souyuz is in a lower orbit...the ISS both has a longer orbital period and a slower orbital velocity. It takes more energy in order to get into a higher orbit, however once in that higher orbit, your velocity is slower.
For an extreme example to illustrate this point, by using their logic the moon should be moving a lot faster since it is in an even higher energy orbit...however its orbital velocity is only 1km/s vs the ISS/Soyuz which is much closer to 7.8 km/s. The only time the soyuz moves slower once in orbit is at the higher portion of an elliptical orbit after doing a hohmann transfer, and before doing a circularization burn. (Edit: And after tapping on the brakes to dock)
TLDR: Play Kerbal Space Program
Video of the "fancy stick" for the center seat:
https://youtu.be/AVvgpKt5uCA?t=396
I LOVE your enthusiasm when talking about this subject and it was a really awesome video! What a great insight with Reid Wiseman, Scot Kelly and you :D
I have a question though. As you said in the video, we all think that the Soyuz would go to the ISS in a spirale orbit.
Why is it not the case ? Is it because functioning by gradual orbits is safer (in case there's a problem, one can still wait for the next "turn") or cheaper ?
Smarter everyday has to be one of the better educational channels out there.
This is all I could think of when he showed the U-turn in space http://youtu.be/cUO9gvGy9Ck
I just watched his clip about the stone fish. Man, this guy has the best channel!
https://www.youtube.com/watch?v=I8yJkIuvPvM