I’m going to be very disappointed if the rockets top out at 65mph.
In: Planetary Science
The point in the earth’s surface that it’s 250iles away from is moving at 17000mph. A bit less because geometry, but not by much.
The top of MT Everest is only 8km away. 90 minute walk no?….
It takes about 10 minutes to reach the ISS orbital speed and velocity, but you don’t go directly to the station. You’ll do some checks once you’re in orbit to ensure that the craft is still operating normally after all the vibrations from launch, then you will slowly adjust your orbit to synchronise with the ISS.
The reason you do this is because the ISS Is very big and expensive and fragile, you want to approach it slowly so if your craft has a complete systems failure the ISS can move out of the way and avoid a collision. You also don’t want to fire your thrusters directly at the station so you approach slowly from a slight angle. Movement in orbits doesn’t work the same way as on earth, so there’s a while long checklist of careful movements that need to be followed.
So most of the time is spent in orbit doing checks and slowly aligning orbits. You could theoretically launch directly to the ISS and that would take about an hour, but this would be very dangerous to the station if anything went wrong. A fast ascent takes about 4 hours and a regular rendezvous can take about a day in total.
Because it’s not straight up. The crew is basically fired at an arc then they go chasing the ISS station.
Because you aren’t flying straight to it. You fly up on an angle then start orbiting behind it and need to slowly catch up to it.
It takes only 8 minutes to get into orbit.
But to approach the target slowly one has to get into precise spot at a precise time and with the right direction and magnitude of velocity. That is very constraining. Unless one has a lot of fuel to spend on aggressive maneuvering one has to take time for the orbital mechanics to do its work naturally.
In principle, it is certainly possible to dock faster than in 4 hours, and such things had been demonstrated. In 1966, [Gemini XI](https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1966-081A), for example, docked after about an hour and a half with a target in orbit.
It is just safer and more convenient to do everything more gradually, with a careful measurement of intermediate trajectory, with testing of the systems before approaching the station, with not putting debris into orbits intersecting the orbit of ISS, etc.
You can get there much faster if you’re cool rendezvousing at thousands of mph. Wouldn’t recommend.
Structural tolerances and safety considerations mean you want to bring your relative velocity down to something like 0.1-0.2mph. So you simultaneously need to get up to ~17500mph, get relatively close, match trajectory and speed extremely closely, and have your docking port meet theirs gently. This takes several maneuvers, and you’re not going to rush it because you have a handful of borderline irreplaceable astronauts, billions of dollars in tough to replace equipment and significant time invested into experiments.
Space is only 100km up. It doesn’t take that long to get up there, less than 5 minutes typically.
The Earth’s diameter is over 12,000km.
Blue Origin have been to space. That’s easy. In order to stay in space you have to go really fast around the planet, such that when you fall you miss the ground.
It doesn’t take long to get into space. It takes longer to make sure you stay in space. After that, to get to the ISS you have to rendezvous with it. Throw in a good chunk of safety margins and you get a lot of time.
A well timed ballistic rocket wouldn’t take that long to hit the ISS.
>I’m going to be very disappointed if the rockets top out at 65mph.
The ISS orbits the earth at 17,100mph relative to the ground.
Have you ever climbed a mountain?
The top of the mountain may only be a mile away.
But how long does it take you to walk that particular mile?
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