I’m going to be very disappointed if the rockets top out at 65mph.
In: Planetary Science
It takes at least several hours to get to the space station because it’s fragile, expensive, and full of people you don’t want to die.
If you just wanted to get there in the same way that a missile strike gets somewhere, you could indeed do that much more quickly.
I think one of the most basic misunderstandings of space travel is how satellites stay up there. Most people think you go up high and then you’re “above the gravity” or something and you just hang there. That is not at all how it works. The ISS experiences nearly as much gravity as on earth. The way it stays up there is by traveling so fast “sideways” that as it falls the curve of the fall is the same as the curve of the earth. The exact speed depends on how far you are from the earth, but for the ISS it’s about 17,500 mph.
So not only do you have to get up 250 miles, you also have to go sideways fast enough to catch the ISS and stay in orbit yourself.
It’s quite a thing, really.
Well imagine you’re driving 75mph and want to catch up to a car ahead of you, 5 miles away driving 70mph. It would take you an hour to catch up despite driving 75mph. And now imagine you not only want to catch up but you actually want to connect your car with the car in front of you. Hitting the other car with 5mph difference might be too rough so ylas you approach you slowly match your speed with the speed of the other car. So that when you connect the difference in speeds are maybe only 1mph. Change the numbers to roughly 5mps for the iss and you certainly don’t want to bump into it with 1 mile per second difference so you’ll have to decelerate even more as you approach…that takes time, and not because anything is slow but because everything is so fucking fast.
Getting into orbit is not about going up, it’s about going sideways REALLY fast. If you throw a ball it drops to the ground a few seconds later. Imagine you could throw it so fast it went over the horizon. Now imagine you could throw it so fast that it kept going over the horizon before it would hit the ground. It would just keep going forever. To make this work you need to first get up and out of the earth’s atmosphere, so that air and wind don’t slow it down.
You COULD get to the ISS in 4 hours going straight up at 65mph, if you timed it just right. However, while you could reach it, it would be going 18,000kmph sideways. You would just be hovering still in the air, like a ball thrown straight up right at the top of its arc. It would not end well for anyone.
can’t they just time it so that after travelling 250miles the ISS is right in front of the rocket? 💀
Meeting up with a craft in orbit isn’t like going straight to a destination. You need your own orbit and your target’s orbit to intersect at just the right spot so that you both get there at the same time. Sometimes that involves waiting in a ”parking” orbit until you get that perfect alignment. The result is that you might have to go around the planet a couple of times before you get there.
In short: You don’t want to bump into the $150 billion laboratory, so you play it safe.
They got way faster over time, in the past they were so careful that it took 24 hours. Now the record stands at 3 hours 3 minutes.
It’s the same reason that getting on a flight doesn’t take, say, 30 minutes when the airport is 15 miles away. You have to go through all sorts of extra things to get there that you wouldn’t have to worry about if you’re going in a straight line without stopping.
Also, the ISS is 250 miles up, but it’s much, much, much, much more distance farther away even just minutes later because it’s going so fast.
So imagine this: you want to get on a bus that’s on a racetrack and is zipping around at 100 miles per hour. When it’s at its closest, it’s just 50 feet away from you. Now picture yourself getting in another bus, and that bus has to accelerate to 100 miles per hour. It has to start accelerating at the right time to end up going 100 miles per hour at about the same place on the racetrack as the other bus, else you’d have to travel a good distance to catch up to the other bus.
All that time accelerating, catching up, mostly matching speed, then slowly coming up to the other bus takes a LOT more time than just walking 50 feet.
Going to the ISS is harder than finding a needle in a haystack. The sheer size of space, even in low earth orbit, and the speed it’s going make it incredibly hard to do.
Because there’s a huge different between a road trip and escaping the earth’s gravity?
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