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2021-11-11, 15:17   #4390
Dr Sardonicus

Feb 2017
Nowhere

5·1,069 Posts

Quote:
 Originally Posted by firejuggler Instead of using fuel to launch satellite in space, this company propose to use a slingshot for the first part (aka exit athmosphere) https://newatlas.com/space/spinlaunc...-first-flight/ is a short news article about it https://www.spinlaunch.com/ is the website I 'm split between and
The description "slightly taller than the Statue of Liberty" is ambiguous. It doesn't specify whether it includes the height of the pedestal, which is about as tall as the statue itself.

So as an exercise, I plugged v = 5000 mph and a = 10000 g's into the formula

$a\;=\;\frac{v^{2}}{r}\text{ or }r\;=\;\frac{v^{2}}{a}$

to work out the radius of the sling. It came out to around 51 m. This is close to the height of the statue itself, from the feet to the top of the torch. The height of the "sling chamber" is a bit more than twice the radius, hence a bit more than the height of the statue, including the pedestal, measured from the ground.

 2021-11-11, 16:47 #4391 Uncwilly 6809 > 6502     """"""""""""""""""" Aug 2003 101×103 Posts 33×379 Posts What about the Slingatron? They have not made much progress either.
2021-11-11, 17:04   #4392
axn

Jun 2003

122218 Posts

Quote:
 Originally Posted by Dr Sardonicus The description "slightly taller than the Statue of Liberty" is ambiguous. It doesn't specify whether it includes the height of the pedestal, which is about as tall as the statue itself.
Check out the video. It has a visual comparison.

2021-11-11, 17:29   #4393
xilman
Bamboozled!

"𒉺𒌌𒇷𒆷𒀭"
May 2003
Down not across

31·359 Posts

Quote:
 Originally Posted by firejuggler Instead of using fuel to launch satellite in space, this company propose to use a slingshot for the first part (aka exit athmosphere) https://newatlas.com/space/spinlaunc...-first-flight/ is a short news article about it https://www.spinlaunch.com/ is the website I 'm split between and
Would work very nicely on the moon where orbital velocity is very much lower than here and where there isn't an atmosphere in the way.

No need to produce chemical fuels from local water either as it could be powered from photovoltaics or a fission reactor flown in from the Earth.

2021-11-11, 18:28   #4394
Dr Sardonicus

Feb 2017
Nowhere

5×1,069 Posts

When I saw the radius of the sling was about as long as the Statue of Liberty is tall, I thought of the statue placed along a radius, and tried to visualize what would happen to it as the machine revved up. I fear Lady Liberty would not fare too well.

But - onward and upward! The trusty formula I used before tells us something about the more ambitious goal of slinging something into orbit.

Getting to LEO would require about 3.5 times the 5000 mph the Suborbital Accelerator is said to be capable of. Assuming the L100 Orbital Mass Accelerator keeps the acceleration at "only" 10000 g's, the radius of the sling would have to increase by a factor of 3.52 or 12.25 to get to 17500 mph.

OK, so much for getting something up to speed inside the launch chamber. But then what?

I had been sort of wondering about what would happen to something exiting a vacuum chamber and hitting the lower atmosphere at 5000 mph. If nothing else, it will probably slow down fairly rapidly.

For something exiting a vacuum chamber and hitting the lower atmosphere at 17500 mph, I'm wondering if overheating might be a problem.
Quote:
 Originally Posted by xilman Would work very nicely on the moon where orbital velocity is very much lower than here and where there isn't an atmosphere in the way.
Indeed...

 2021-11-19, 17:18 #4395 Xyzzy     Aug 2002 20D516 Posts
2021-11-20, 12:21   #4396
kriesel

"TF79LL86GIMPS96gpu17"
Mar 2017
US midwest

2×3,049 Posts

Quote:
 Originally Posted by Xyzzy https://www.quantamagazine.org/the-s...buns-20211118/
10 vs 8? Because sometimes a dog goes without a bun. A niece refused to eat anything else for months when young. (Now a vegetarian, go figure.)

 2021-11-20, 14:16 #4397 Dr Sardonicus     Feb 2017 Nowhere 5×1,069 Posts Besides simply being eaten without buns, or with alternative wraps, "orphan" hot dogs can be sliced and added to other things - baked beans, macaroni and cheese, etc. I note that in some cases, "shrinkflation" has reduced hot dog buns to the point of inadequacy. Assume the buns are the usual white air bread. A one pound 8-pack would have two ounces of bread per bun. But a 12-ounce 8-pack only has 1.5 ounces of bread per bun. (There are even 11-ounce 8-packs.) Put a dog with fixings in one of those skimpy things, and it will likely disintegrate in your hand. Such buns are not worth buying at all, definitively solving the matchup problem.
2021-11-20, 14:31   #4398
kriesel

"TF79LL86GIMPS96gpu17"
Mar 2017
US midwest

2×3,049 Posts

Quote:
 Originally Posted by Dr Sardonicus Such buns are not worth buying at all, definitively solving the matchup problem.
A slice of multigrain bread works for me. More digestible than the gummy pasty-white buns, too. Less frequent structural failure at the hinge is a bonus. Plus better cost.

Last fiddled with by kriesel on 2021-11-20 at 14:32

 2021-11-20, 14:41 #4399 rogue     "Mark" Apr 2003 Between here and the 6,529 Posts Better question, is a hot dog in a bun considered a sandwich?
2021-11-20, 15:09   #4400
EdH

"Ed Hall"
Dec 2009

33·5·31 Posts

Quote:
 Originally Posted by rogue Better question, is a hot dog in a bun considered a sandwich?
As soon as the hinge breaks, Yes.

As for health, I have moved to bun-less, although the healthfulness of the "dog" itself is still a question.

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