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We need a better way to get to space

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Re: We need a better way to get to space

#11

Post by noir_lord »

anon8764 wrote: post #7

www.et3.com gradually leading up to the top of everest, jettisoning the capsule (6,500 km/h (4,000 mph)) to break out of the atmosphere. I have not done the math, physics, etc on this, but it's an interesting idea worth exploring. But that said, do we really belong in space when we cannot care for our own? Wouldn't that be akin to giving sugar to ants? only multiplying suffering and cruelty exponentially in space? Pe…

Pushing boundaries technologically has a tendency to pull others along with it, accessing space cheaply would have the potential to create entire new markets and access to new resources all of which would help in the long term everyone else.

Re: We need a better way to get to space

#12

Post by anon8764 »

grogenaut wrote: post #10
anon8764 wrote: post #7

www.et3.com gradually leading up to the top of everest, jettisoning the capsule (6,500 km/h (4,000 mph)) to break out of the atmosphere. I have not done the math, physics, etc on this, but it's an interesting idea worth exploring. But that said, do we really belong in space when we cannot care for our own? Wouldn't that be akin to giving sugar to ants? only multiplying suffering and cruelty exponentially in space? Pe…

If people had waited to leave Europe until the 1970s the culture had been "refactored" enough for the masses, I doubt the world would have advanced as far as it had and the pressure of the population growth from industrialization would have caused some real issues. Actually I think it might be refactored even worse for the masses. Letting the average person go out and build new things helped a lot. Also, do you reall…

Perhaps technology has advanced too fast for the "culture". Perhaps we should design our intentions before we build the tech, and not the other way around. Look at NASA for inspiration on design and forethought.

Re: We need a better way to get to space

#13

Post by mmastrac »

nickff wrote: post #8
rikkus wrote: post #6

20 years ago, I remember dreaming up a train pulling a cable with a glider at the far end. I'm sure there are many technical issues with this approach, possibly including the cable needing to be incredibly strong, light and flexible. Please tell me it would work, though, as I still enjoy the mental image.

Reaching orbit is mostly an issue of velocity, not altitude. This is why balloons can get very high, above of almost all earth's atmosphere, while being far from orbit. Rockets spend most of their ascent traveling nearly horizontal to the ground (they only go straight up at the beginning to get out of the densest part of the atmosphere).

Exactly. The most expensive part of getting to orbit is circularization. It takes a delta-vee of ~9.4km/s to reach LEO from earth. If you could lift yourself into LEO altitude without any thrust, you'd still have to circularize to the orbital velocity of ~8km/s [!]. That's still the majority of your delta-vee!

[!] I am not a rocket scientist, so I haven't taken into account the orbital velocity you'd get from being rooted on the earth at takeoff, but it should be at most ~500m/s.

Re: We need a better way to get to space

#15

Post by skizm »

So is infertility in astronauts still a problem? I could be totally wrong, but I was under the impression we haven't solved the problem of increased radiation negatively affecting fertility in both male and female astronauts.

Re: We need a better way to get to space

#16

Post by baldfat »

nickff wrote: post #8
rikkus wrote: post #6

20 years ago, I remember dreaming up a train pulling a cable with a glider at the far end. I'm sure there are many technical issues with this approach, possibly including the cable needing to be incredibly strong, light and flexible. Please tell me it would work, though, as I still enjoy the mental image.

Reaching orbit is mostly an issue of velocity, not altitude. This is why balloons can get very high, above of almost all earth's atmosphere, while being far from orbit. Rockets spend most of their ascent traveling nearly horizontal to the ground (they only go straight up at the beginning to get out of the densest part of the atmosphere).

The train would glide the aircraft to the mesosphere (50 km or 31 miles) and than rocket to orbit? So you would need 62+ miles of track going hundreds of miles an hour at 45 degree angle with the tow rope?

Re: We need a better way to get to space

#18

Post by grogenaut »

anon8764 wrote: post #12
grogenaut wrote: post #10

Earlier quoted context omitted.

If people had waited to leave Europe until the 1970s the culture had been "refactored" enough for the masses, I doubt the world would have advanced as far as it had and the pressure of the population growth from industrialization would have caused some real issues. Actually I think it might be refactored even worse for the masses. Letting the average person go out and build new things helped a lot. Also, do you reall…

Perhaps technology has advanced too fast for the "culture". Perhaps we should design our intentions before we build the tech, and not the other way around. Look at NASA for inspiration on design and forethought.

The problem with this is you're designing based on your current world view and assumptions. When does this type of planning ever work and actually stand up to 20 years of history? 40? 100? In the 50's the us was DESIGNED around the car and suburbs. That worked well.

Re: We need a better way to get to space

#19

Post by reitanqild »

anon8764 wrote: post #7

www.et3.com gradually leading up to the top of everest, jettisoning the capsule (6,500 km/h (4,000 mph)) to break out of the atmosphere. I have not done the math, physics, etc on this, but it's an interesting idea worth exploring. But that said, do we really belong in space when we cannot care for our own? Wouldn't that be akin to giving sugar to ants? only multiplying suffering and cruelty exponentially in space? Pe…

(anon8764 was downvoted when I wrote this.)

I disagree but still upvoted this to get it to 0. I find the tought interesting but wrong. It seems more suffering is caused by various misguided attempts at refactoring culture etc and less by technology.

National socialism and communism are two widely known attempts at refactoring culture that has created more misery than all technological advances combined so far.

Re: We need a better way to get to space

#20

Post by chris_va »

iwwr wrote: post #9
aggieben wrote: post #5

Giant railguns. That is all.

Light-gas guns may be a good contender while railguns are sorted out. https://en.wikipedia.org/wiki/Light-gas_gun

Surprisingly, I actually did a fair bit of research into this field.

Both rail guns and light gas guns cap out at around 6km/s, and you really want 8km/s (more actually, for hypersonic drag loss) for this to be economical. Otherwise you need to launch a large enough rocket to make up the 2km/s difference, and you stuck solving the rocket equation again. Except you've subjected your rocket to 1000g, and the odds of it being reusable are really small.

For rail guns, the plasma discharge on the rails limits your speed. Around 6km/s.

For light gas guns, the working temperature of the gas cannot exceed the melting point of the barrel (or get close), otherwise tungsten/steel will get into the working gas and slow down the speed of sound. With hydrogen+tungsten, also around 6km/s.

There is a better solution, though :).

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