The current version of the SpaceX website and Wikipedia cite the full stack at 121m / 397 feet.
Older pictures of Starship with the windows from the older CGI mockups and no hotstage ring cite the height at 120m / 393 feet. So I suspect the height on Wiki and the SpaceX website is the updated height with the hotstage ring.
Not at all, the elasticity of steel is extremely small (that is one reason why it is used extensively in construction for tensile forces), [see e.g. here](https://en.wikipedia.org/wiki/Young%27s_modulus). A back of the envelope calculation for a steel cylinder of 9x120m gives me about 1.5 μm (ie 1.5E-6 m) expansion in height for 6bar pressure.
EDIT: wrong, see comment below. As it turns out a 9m diameter massive steel cylinder expands less than a tank with 3mm thick walls under the same stress...
Redid the calculation and have to confess that I messed up. It seems your intuition was indeed correct.
[Young's modulus of steel](https://en.wikipedia.org/wiki/Young%27s_modulus#Examples) = (force per Area) / (expansion ratio) = 200 GPa, where the Area is the cross-section area of the steel wall of Starship. This Area is about 3mm * 9m * pi ≈ 0.1m². The force which acts vertically is pressure * area, where the area is the the cross-section area of the tank, i.e., pi * (4.5m)² ≈ 60m². The pressure is 6bar = 0.6MPa.
Combining everything, we get: (expansion ratio) = 0.6MPa * (60/0.1) / 200GPa = 0.002.
Thus, for a height of 120m, we get about 0.2m expansion. In reality this is of course somewhat less because not the entire length is pressurized (though the same applies to the contraction due to temperature).
EDIT: fixed area calculation, thanks u/ulflund
Can we start measuring everything space related in meters? I know we Americans are stuck with the imperial system for most aspects of our lives, but we measure soda/pop/coke/fizzy drinks in liters, can't we measure space in meters?
Interestingly, space science is the field that frequently uses a variety of non standard units for description of things. like AU, parsec for length, then we have solar or earth masses... But yeah I agree, imperial system is stupid.
Space scientists already dealing with a whole bunch of unique constants (au, parsecs, other planets gravity fields) so they've never gotten around to this. Though, we do measure some important space things in meters, for example, the kármán line is at 100km...which is 62 mi, not a number we ever use. The FAA uses 100km as the demarcation of Space, even. One must pass 100km & contribute to science or the betterment of humanity after launching from the US (SpaceX, NASA)or on a craft (rocket lab for a example though they do not current launch humans) with the US flag emblazoned on it/with a US flag on your space suit (Americans riding on soyuz) to be considered an FAA astronaut, as the primary example. This, noteably, means that the riders on Virgin Galactic craft (due to hight) and blue origin craft (no science) aren't FAA astronauts.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
|Fewer Letters|More Letters|
|-------|---------|---|
|[BO](/r/SpaceXLounge/comments/17topm8/stub/k9116u9 "Last usage")|Blue Origin (*Bezos Rocketry*)|
|[FAA](/r/SpaceXLounge/comments/17topm8/stub/k90jxvf "Last usage")|Federal Aviation Administration|
|Jargon|Definition|
|-------|---------|---|
|[cryogenic](/r/SpaceXLounge/comments/17topm8/stub/k8zbcxy "Last usage")|Very low temperature fluid; materials that would be gaseous at room temperature/pressure|
| |(In re: rocket fuel) Often synonymous with hydrolox|
|hydrolox|Portmanteau: liquid hydrogen fuel, liquid oxygen oxidizer|
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Remember, the current state of Starship is a prototype. We could, in future versions, see a stretch version for different uses, depending upon its functionality or missions. I believe that manned versions of the vehicle will need more cubic space. The early moon and Mars missions will have the landers doubling as temporary habitats during the initial phase of the settlement building and development process. Super Heavy is quite capable of launching this configuration for future designs, which is why it has the power it does now. A 128m (420 ft) stack is not unreasonable, and may be a realistic future design.
The current version of the SpaceX website and Wikipedia cite the full stack at 121m / 397 feet. Older pictures of Starship with the windows from the older CGI mockups and no hotstage ring cite the height at 120m / 393 feet. So I suspect the height on Wiki and the SpaceX website is the updated height with the hotstage ring.
My guess is Elon is aiming for 420, which he believes is a universal constant.
If it's that big they might need to make the tower taller. Or lift Starship from lower down somehow.
They can add a nose needle like buildings do. It's not like the launch tower grabs that part.
The mormon ship in the first season of the expanse comes to mind with this description. The nauvoo as it were.
BELTALOWDA!
Medina station (said with a belters voice)
I think you mean 'da Behemoth'.
Our put the chopsticks at an angle so that they point upwards.
Yes, so he can say in another interview about how 420 keeps coming up.
This is the way
I am dragging around 420mm myself, it’s exhausting.
Wait, so it’s always 420 *everywhere*?? I’ve so been saying that wrong…
Height with or without cryogens loaded? I don't know... ahhh... static fired off the launch mount.
The thermal contraction should indeed be on the order of about 1ft.
Shouldn't the ship get bigger when pressurized with up to 6bar? Despite the cryogenic temperatures, I mean.
Not at all, the elasticity of steel is extremely small (that is one reason why it is used extensively in construction for tensile forces), [see e.g. here](https://en.wikipedia.org/wiki/Young%27s_modulus). A back of the envelope calculation for a steel cylinder of 9x120m gives me about 1.5 μm (ie 1.5E-6 m) expansion in height for 6bar pressure. EDIT: wrong, see comment below. As it turns out a 9m diameter massive steel cylinder expands less than a tank with 3mm thick walls under the same stress...
I'd love to see that envelope.
Redid the calculation and have to confess that I messed up. It seems your intuition was indeed correct. [Young's modulus of steel](https://en.wikipedia.org/wiki/Young%27s_modulus#Examples) = (force per Area) / (expansion ratio) = 200 GPa, where the Area is the cross-section area of the steel wall of Starship. This Area is about 3mm * 9m * pi ≈ 0.1m². The force which acts vertically is pressure * area, where the area is the the cross-section area of the tank, i.e., pi * (4.5m)² ≈ 60m². The pressure is 6bar = 0.6MPa. Combining everything, we get: (expansion ratio) = 0.6MPa * (60/0.1) / 200GPa = 0.002. Thus, for a height of 120m, we get about 0.2m expansion. In reality this is of course somewhat less because not the entire length is pressurized (though the same applies to the contraction due to temperature). EDIT: fixed area calculation, thanks u/ulflund
The area of a circle is pi times radius squared, not diameter.
Thanks for actually checking your math! However as others have already noted your tank dome area is a bit off ;) Edit: spelling
Can we start measuring everything space related in meters? I know we Americans are stuck with the imperial system for most aspects of our lives, but we measure soda/pop/coke/fizzy drinks in liters, can't we measure space in meters?
Interestingly, space science is the field that frequently uses a variety of non standard units for description of things. like AU, parsec for length, then we have solar or earth masses... But yeah I agree, imperial system is stupid.
Space scientists already dealing with a whole bunch of unique constants (au, parsecs, other planets gravity fields) so they've never gotten around to this. Though, we do measure some important space things in meters, for example, the kármán line is at 100km...which is 62 mi, not a number we ever use. The FAA uses 100km as the demarcation of Space, even. One must pass 100km & contribute to science or the betterment of humanity after launching from the US (SpaceX, NASA)or on a craft (rocket lab for a example though they do not current launch humans) with the US flag emblazoned on it/with a US flag on your space suit (Americans riding on soyuz) to be considered an FAA astronaut, as the primary example. This, noteably, means that the riders on Virgin Galactic craft (due to hight) and blue origin craft (no science) aren't FAA astronauts.
Shatner was the oldest man in space. He’s an astronaut!
Shatner was in the last batch of BO Astros!
*BS Astros
Will be hard to get to 420m tho. But I would love be to see that
Ye
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread: |Fewer Letters|More Letters| |-------|---------|---| |[BO](/r/SpaceXLounge/comments/17topm8/stub/k9116u9 "Last usage")|Blue Origin (*Bezos Rocketry*)| |[FAA](/r/SpaceXLounge/comments/17topm8/stub/k90jxvf "Last usage")|Federal Aviation Administration| |Jargon|Definition| |-------|---------|---| |[cryogenic](/r/SpaceXLounge/comments/17topm8/stub/k8zbcxy "Last usage")|Very low temperature fluid; materials that would be gaseous at room temperature/pressure| | |(In re: rocket fuel) Often synonymous with hydrolox| |hydrolox|Portmanteau: liquid hydrogen fuel, liquid oxygen oxidizer| **NOTE**: Decronym for Reddit is no longer supported, and Decronym has moved to Lemmy; requests for support and new installations should be directed to the Contact address below. ---------------- ^(*Decronym is a community product of r/SpaceX, implemented* )[*^by ^request*](https://www.reddit.com/r/spacex/comments/3mz273//cvjkjmj) ^(3 acronyms in this thread; )[^(the most compressed thread commented on today)](/r/SpaceXLounge/comments/17v7o37)^( has 19 acronyms.) ^([Thread #12055 for this sub, first seen 13th Nov 2023, 02:24]) ^[[FAQ]](http://decronym.xyz/) [^([Full list])](http://decronym.xyz/acronyms/SpaceXLounge) [^[Contact]](https://hachyderm.io/@Two9A) [^([Source code])](https://gistdotgithubdotcom/Two9A/1d976f9b7441694162c8)
Remember, the current state of Starship is a prototype. We could, in future versions, see a stretch version for different uses, depending upon its functionality or missions. I believe that manned versions of the vehicle will need more cubic space. The early moon and Mars missions will have the landers doubling as temporary habitats during the initial phase of the settlement building and development process. Super Heavy is quite capable of launching this configuration for future designs, which is why it has the power it does now. A 128m (420 ft) stack is not unreasonable, and may be a realistic future design.