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Space Elevator

neal.fun

101–110 of 216 posts

Re: Space Elevator

#103
post #62

Couple of things I learned from this: 1. Some birds go really high into the sky. Not sure how they evolved to tolerate such a hostile environment. But it seems that Duck-like birds are able to handle very high altitude. 2. There are lots of cool spaceships that man has made. But it seems most of these were made in the 1950-1990 era. It's a shame that we are no longer doing that.

To your 2nd point, I'd venture an uneducated guess that the reason we were doing this was largely a part of the arms race between USA and USSR during that period.

Re: Space Elevator

#104
post #87

Earlier quoted context omitted.

I have to wonder what you mean we're no longer making cool spacecraft? The SpaceX starship is about to launch in an hour, it's very cool.

Watching the countdown now! T-00:28:12! Will be spectacular no matter what happens! Yes, I'm excited. Not sure how the parent comment has missed what SpaceX has been doing with Dragon, Starship, Starlink, and all the rockets! Amazing.

It exploded when trying to orient for the first stage separation. And it appeared to have 5 of the 33 engines out during the first stage flight. This launch gave me very "Don't Look Up" ending vibes.

Re: Space Elevator

#107
post #33

Earlier quoted context omitted.

Yes, it absolutely has to taper, with an exponential curve, to keep stress constant over the length of the cable. The taper ratio (in terms of cross-sectional area) for the best currently available engineering materials for an Earth space elevator would be in the tens to hundreds of millions, but a carbon nanotube cable might only require a taper ratio of around ten. (A steel cable would need a taper ratio on the ord…

I believe A taper ratio of 10 means a 5cm rope at the bottom would be 50cm at the top. A steel cable would be 1mm thick at the bottom and several light years* thick at the top. *hyperbole. Maybe.

It’s a function of area so if we scale equally in both dimensions, a taper ratio of 10 means a thickness ratio of ~3.2. But yeah, that doesn’t exactly buy us much.

Re: Space Elevator

#108
(Sorry, am not a science person). Why does the temperature go down until 11000 metres, then stay at -70F until 20000m, then starts going back up to 28F until 50000m, then starts going down again 83500m, stays at -119F until 90500m, rises up again until 100000m ?

Re: Space Elevator

#109
post #62

Couple of things I learned from this: 1. Some birds go really high into the sky. Not sure how they evolved to tolerate such a hostile environment. But it seems that Duck-like birds are able to handle very high altitude. 2. There are lots of cool spaceships that man has made. But it seems most of these were made in the 1950-1990 era. It's a shame that we are no longer doing that.

List of cool spaceships being worked on now or recently:

* The Falcon 9, the first partially reusable spaceship that actually costs less than not re-using anything

* Terran R - a fully reusable space ship in the works by relativity space

* RocketLab Electron - an active rocket that is unique in its use of electric turbo pumps, 3d printed engines, and advanced composites use

* RocketLab Neutron - in the works, a larger rocket with the aim to be partially re-usable ala Falcon 9 but with a cheaper expendable 2nd stage and simpler design

* SpaceX Starship - in the works, (test flight today!) a large heavy lift vehicle with the aim to be fully reusable

* Blue Origin - working on a ship similar to starship

there are others!

Re: Space Elevator

#110
post #62

Couple of things I learned from this: 1. Some birds go really high into the sky. Not sure how they evolved to tolerate such a hostile environment. But it seems that Duck-like birds are able to handle very high altitude. 2. There are lots of cool spaceships that man has made. But it seems most of these were made in the 1950-1990 era. It's a shame that we are no longer doing that.

I think there's a lot of craft we just don't know about.
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