SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

kbd512 · 2023-05-16 16:07:34

RGClark,

By that metric, yes, I would agree that asserting one rocket will handle all space launch activities is rather silly.

However...

If Starship can drive launch costs low enough, then we don't need highly creative engineering for our satellite technology. We can use a lesser number of very large satellites, not made from inordinately expensive aerospace materials like Magnesium or Beryllium alloys and CFRP. If plain old steel will cost a lot less money, then there's no pressing need to hand-fabricate satellites costing tens of millions per copy. A much larger and more capable satellite, based upon well-shielded commodity electronics, could feasibly provide like-kind capability to constellations of hundreds to thousands of smaller and individually less capable machines. We'd still have satellite constellations, but perhaps dozens of very large orbital platforms servicing multiple telecom providers instead of thousands of smaller ones choking our skies with debris.

Telecom providers already share infrastructure here on Earth to save money on routing new cables into homes and businesses. The cellular service providers also share cell towers. We could do the same thing with the communications satellites so that service providers don't need to reinvent the solar array or batteries. Hopefully, we prevent the glut of satellites from rendering their operating environment unusable through collisions between various different defunct satellites. There's already a cloud of defunct satellites and orbital debris up there, which hasn't improved over time. I think it'd be better if there were fewer machines so that they don't endanger other satellites or human lives.

Void · 2023-05-16 18:51:36

That seems sensible.

I would mention https://www.vastspace.com/

They may support various money centered activities.

Microgravity manufacturing for instance: https://www.factoriesinspace.com/
Quote:

In-space manufacturing could be enabler and first customer for numerous asteroid mining, commercial space station and utility companies in space. If asteroid mining will be a $1 trillion business then in-space manufacturing will be a $10 trillion business thanks to all the materials made into products with extra value.

Nothing is certain, but rather then SpaceX satisfying and saturating demand the existence of the service may cause an expansion of demand.

We will see, I guess.

Done.

Void · 2023-05-17 07:33:03

We think so far in terms of refilling Methane and Oxygen in orbit from Starships. But that would support missions to the Moon and Mars primarily.

Just on a memory my notion is that electric propulsion might be 10 times as efficient as chemical propulsion. Well, it is better in certain ways.

An entire very large expansion of human living space seems likely in LEO and perhaps a bit above LEO. You would not have to do 5 to 6 refills to go to the Moon or Mars to do that. And you would not have to be in a hurry in many cases.

Starship and other ships could do quite a lot without chemical refills. Argon might do a lot.

OK, 10 times as good is probably max, and specs are convoluted as well, apples and oranges and that. https://www.nasa.gov/feature/glenn/2020 … ectrifying
Quote:

This radical system is in-space electric propulsion. It can reduce the amount of fuel, or propellant, needed by up to 90% compared to chemical propulsion systems, saving millions in launch costs while providing greater mission flexibility.

But if one Starship flight could lift 100 to 150 tons, then if half of the cargo were Argon, that would be 50 to 75 tons. That then leaves you with 50 to 75 tons of other cargo. So 50 to 75 tons of Argon is sort of equivalent to several starship propellant runs with Methane and Oxygen in them.

I guess the point is you could stack a lot of stuff inside the Van Allen Belts, above the Earth, and navigate the stuff about rather efficiently.

Thats probably going to be the "Payday" stuff, not the Moon and Mars and asteroids, not yet.

Done

Last edited by Void (2023-05-17 07:45:19)

kbd512 · 2023-05-17 09:12:10

Void,

We will indeed require electric propulsion to economically travel to other planets, which means specialty propellants. Chemical propellants are required to get to space. Once you get there, then you need drastically improved fuel economy. We will never get that from traditional chemical propulsion. Some of the advanced rocket engine concepts like detonation wave can provide modest but meaningful fuel economy improvements, an increase of as much as 25% to 30% better than what we have now. That's more like going from carbs to electronic fuel injection than a paradigm shift. We cannot affordably travel to other planets without a paradigm shift in propulsive efficiency, so we either develop the technology to use high-power in-space electric propulsion, or we give up on the idea of colonizing other planets.

We already know what we must do. It's so obvious.

Step #1: Develop and fly low-cost fully and rapidly reusable super heavy lift rockets.
Step #2: Develop and fly high-efficiency / high-power in-space electric propulsion capable of reliably providing thousands of hours of continuous operation.
Step #3: Demonstrate completely closed-loop life support that minimizes per-person power consumption, over at least 2 years of operation.
Step #4: Grow food on other planets or in-orbit, and maintain human health under different gravity regimes.
Step #5: Demonstrate high-reliability / minimum complexity / long-term maintainable photovoltaic and nuclear fission or fusion power generation systems that do not appreciably degrade over decades of operations.

Once we have all that technology figured out, to the point that however we approach the problem we cannot "get it wrong", then there's nothing stopping us from living on other planets. We can live anywhere within our solar system at that point.

We will need to develop a working warp drive to reach other stars. That is Step #6. No other solution is practical. Steps #6 will only become a consideration after Steps #1 through #5 have been completed. Concurrent development of each requirement will decrease the timeline required to leave our solar system.

Starship is only the beginning of the interplanetary and interstellar technology development phase. We're a long, long way from being ready. I find it a bit humorous how some people are going bonkers over the fact that we're actually doing this. I don't know what they're so afraid of, but they seem terrified that someone will succeed in pushing the technology set forward.

Void · 2023-05-17 09:25:59

Good, agreed at least 1-5 and quite possibly. 6.

A factor has now occurred to me. I think the logic of SpaceX going with Stainless Steel for Starship, holds up as propellants are cheap here on Earth, but in space locations they may often still be precious.

Rocket Labs is said to have a method to build rapidly with Carbon, and there may be other light weight materials. I think that as you go beyond LEO, reconsideration of the use of lighter materials may be warranted.

It can still be sensible to start a Martian Base by landing some Stainless-Steel Starships, since extra copies of them could be made, but down the road, efficiency from weight reduction could be important.

Done.

Last edited by Void (2023-05-17 09:30:17)

kbd512 · 2023-05-17 11:13:02

Void,

I hope that Rocket Lab has found a way to economically fabricate from CFRP, but plastic performance remains problematic when high thermal loads are involved. Protection is required, which adds weight back, along with considerable cost over steel for the base materials used. If a rocket was purely used in-space, then CFRP tankage certainly helps, but not that much. The stainless steel balloon tanks used by Centaur upper stages are around 95% propellant mass fraction and using the highest Isp bi-propellant in existence. Gaining a couple more percentage points of propellant mass fraction is practically meaningless. The Rutherford engine eliminates most of the unusable propellant volume as well, since its turbopump motors are electric and don't need to worry about cavitation as much.

We have LH2, LCH4, kerosene, and some hypergolic chemicals as practical fuel choices. LOX tends to be the most performant oxidizer, irrespective of fuel selection. We have extreme performance engines that are highly optimized to work in vacuum or dense atmospheres. The detonation wave engines are our last stop for significant Isp improvements. Everything else will be refinement, mostly centered around reliability and longevity in operation. I have no issue with taking the technology as far as we can, but we're rapidly approaching limits.

Even if we perfected CNT and BNNT structures for tankage and detonation wave engines, we simply cannot buy ourselves much additional performance from LOX/LH2. Only a stronger but absurdly toxic oxidizer such as Fluorine can significantly improve upon LOX. We already have full-flow staged combustion, self-pressurization of tankage, combustion engines or fuel cells to replace the heavier batteries, electro-hydraulic TVC actuators, 3D printing of large / complex parts, and solid state miniaturized electronics providing full engine instrumentation for every flight.

So, yes, take those chemical rocket engines to their zenith, but start devoting more money to electric propulsion and photovoltaics or reactors that can supply the power required. The propulsion technologies dictate where we can go, how often we can go, how many people can go... you get the idea. We should do the same thing with propellant tank fabrication technology, but as we approach the apex of capability using known materials and fabrication methods, we start devoting more funding to "next steps".

tahanson43206 · 2023-05-17 13:41:19

For all ... here is a YouTube presentation by Dr. Greg Stanley about the rotating stage separation method for Starship.

https://www.youtube.com/watch?v=yesni8HUEA4

(th)

SpaceNut · 2023-05-17 19:00:31

Add one more alteration to the starship a tank delivery ship that could open the nose and dock to a depot that once latched onto the starship would back away and the tank would extract from within the ship leaving it attached to the depot. An umbrella would extend and would shade the tank to reduce boil off at the depot while waiting for others to do the same.

edit
hope this image shows what I am intending with the tank dispensing.
20210321_225233_2000x.jpg?v=1616385634

RobertDyck · 2023-05-18 15:01:36

You don't want to waste material; especially heavy material that costs money to lift into space. You could deliver tanks to assemble the depot, but eventually the propellant in those tanks will be drained. So we need in-space propellant transfer. Furthermore, Starship is designed for the cargo hold to be part of the ship during atmospheric entry. Lack of nose section would dramatically alter aerodynamic performance.

I still believe the best solution is a bladder. DpaceX has produced some graphics showing use of propellant to produce acceleration during transfer, but that significantly changes orbit. You wouldn't want to alter velocity that much because it would screw up the orbit. Many flexible materials will not perform when chilled by cryogenics, however PCTFE will. PCTFE becomes embrittled at -240°C. Starship carries densified propellants: LOX -207°C, LCH4 -180. So PCTFE would work.

GW Johnson · 2023-05-19 15:06:55

I have seen this "embrittlement temperature" quoted for PTCFE multiple times. I have never seen it defined in terms of a measurable property.

The relevant property is tensile elongation strain, at cryogenic temperatures. In this case, right around -180 to -207 C.

Whether the design features a simple collapsed bladder, or a real everted bladder, makes no difference. Right at any wrinkle, or at the eversion point, the material has to fold back on itself by 180 degrees. The inside of that fold is in compression, at essentially zero radius of curvature. I'm not so worried about that. But the outside of that fold is in considerable tension, and the required strain is half a circumference of a circle of radius t = thickness of the bladder. In other words, the raw strain is pi*t units of length long.

The actually affected material is more extensive. We can always argue about how much, but I presumed a length of 2*t on each side of the bend. That means the gage length of original material that is to be strained is some 4*t units long. The ratio is the elongation strain that must be reliably had at cryogenic temperatures: pi*t/4*t = 78.5%. Or just about 80%. Independent of the actual thickness t, I might add!

If the gage length of affected material is actually shorter, say only 2*t, for 1*t length affected on each side of the bend, then double that required strain capability. And that could easily be the case!

So, if PTCFE has tensile elongation strain capability in the 80% range at -207 C, then yes, a bladder might be feasible with it, for LOX and LCH4. If the gage length is closer to 2T, the elongation requirement is closer to 160%, and you have to deal with that! It's not me, it's the numbers talking!

For most of the polymers I ever heard of, it is the room temperature elongations that are in that 80+% class. Cold elongations are usually single-digit, or even just a fraction of a single digit.

Let's see an actual cryogenic value of tensile elongation strain-at-failure for PTCFE, before I agree that it might make a cryo-propellant bladder.

Otherwise, let us just say I am extremely skeptical of that notion.

As for cryopropellant ullage without orbit-changing thruster effects, there is end-over-end spin that concentrates the propellant in one or another end of the tank. And there is rifle-bullet spin, which concentrates the propellant in a layer around the tank periphery. Either could be made to work for propellant transfer operations just fine: just put the suctions where the propellant is. Spin-up / spin-down could be by thrusters or by flywheels. Take your pick.

GW

GW Johnson · 2023-05-19 15:33:32

A follow-up on my previous post #160. Cryogenic stress-strain data for PTCFE are hard to find on-line. I did see multiple sources claiming low-crystallization forms of PTCFE had better cold strain the high-crystallization forms. Glassy transition temperatures reported by various sources were all over the map: from 45 C to over 100 C.

I did find one master's thesis from Rice University in Houston, where the student tested for stress-strain all the way down to 4.2 K. Lower-crystalline did better, but the strains at 4.2 K and at 78 K were single-digit %'s. The student's room-temperature strains were near or above 100%, as several other sources also indicated.

Single-digit cryogenic strain-%-to-failure. As I thought they probably would be.

My conclusion: PTCFE is definitely useless as a cryo-propellant bladder, despite its fairly common uses as inserts and liners in valves at cryo temperatures. Those require no strain capability. Bladders do.

Sorry, that's just the numbers.

GW

RGClark · 2023-05-22 07:28:10

There needs to be an overall independent review of the safety of the SuperHeavy/Starship launch. That independent review needs to include the lax standards the FAA applied to the SH/SS launch. SpaceX and the FAA dodged a bullet in the last launch.

Agencies studying safety issues of LOX/methane launch vehicles.
Jeff Foust.
May 20, 2023
WASHINGTON — Three U.S. government agencies are undertaking studies to examine the safety issues associated with a new generation of launch vehicles that use liquid oxygen and methane propellants.
At a May 15 meeting of the Federal Aviation Administration’s Commercial Space Transportation Advisory Group (COMSTAC), FAA officials described efforts that are underway to understand the explosive effects of that propellant combination in the event of a launch accident.
https://spacenews.com/agencies-studying … -vehicles/

Robert Clark

RobertDyck · 2023-05-22 07:46:21

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kbd512 · 2023-05-22 09:10:42

RobertDyck,

What does strain-to-failure look like at cryogenic temperatures for PCTFE?

When the bladder is full, assuming it's appropriately sized for the tank, creep deformation is probably not a concern. Embrittlement would be of much greater concern, but let's assume both failure modes are not applicable to PCTFE at the temperatures involved using LOX and LCH4.

A high-strength steel may exhibit little to no creep and no embrittlement at substantially elevated temperatures, but it's tensile strength will be drastically reduced, so whatever load its placed under will need to be reduced by a lot, else it progressively / plastically deforms to destruction.

When we start "squeezing the bag" while it's full of propellant, how hard can we squeeze before it ruptures from a loss of tensile strength at cryogenic temperatures?

That seems to be what GW was pointing out, at least from my perspective.

Are we using another inflatable PCTFE bag and filling it with gaseous propellant to force out the liquid?

If we do that, do we have to worry about one bag sticking to the other or to the inside of the tank, tearing the bag due to its greatly reduced strain-to-failure that GW's research paper noted from testing?

Some ice is going to form from ambient moisture unless the tank is vacuumed out ahead of filling with propellant, and that little bit of moisture is going to "glue the bags together" or glue the propellant bag to the inside of the tank, so do we have sufficient reserve strength to overcome that little bit of surface moisture to "unstick" the bags and prevent a tear?

I don't imagine this is going to add much weight if it's viable, and it seems like it should work quite well if precautions are taken with moisture and you don't squeeze too hard or too fast, but how much do you figure on?

In my head, a propellant bladder looks like a simpler and more elegant solution than spaceliner ballet or centrifuging or other potentially dangerous mechanisms or maneuvers that could damage the ships. That said, I think a test needs to be performed to know if squeezing the bag will tear it.

tahanson43206 · 2023-05-22 11:38:05

For all ... while I find this endless argument to be quite interesting, every time we go through the loop, there doesn't seem (to me at least) to have an end point other than by actual experiment in orbit.

For RobertDyck ... If you think you have a solution, and can scare up the manufacturers who can make a bladder for a test, it seems to me there is an unmet market that will eventually amount to many billions of monetary units, as space commerce gets underway.

I agree that Dr. Johnson's rotating fuel transfer method is far in the lead right now, for practical application based upon known physics and on-orbit observations of liquid behavior, as an alternative to the tried-and true small-rocket-thruster technique used universally today to settle tanks ahead of a burn.

Is there someone in Canada who would ** really ** like to make a name for themselves, in the space refueling business? If there ** is ** such a person, you are available to design a bladder system, or so I've been told.

The first step in starting a new business is putting a sign over the door. Advertising your availability is the first step.

(th)

Calliban · 2023-05-22 13:15:56

Another option, other than rotation or flexible bladder, is a gas pressurised piston. This would be a cylidrical float in a cylindrical tank, with gas above it and liquid propellant beneath, with a rubber seal around the edges. Gas pressure at the top would push it down, pushing fluid out of the tank like a syringe. The advantage being that you don't need a material that is flexible at cryogenic temperature. I still think rotation is a better option.

Last edited by Calliban (2023-05-22 13:17:10)

RobertDyck · 2023-05-22 14:31:43

kbd512,
The proposed design uses a stainless steel tank with a PCTFE bladder inside. Pressurant is helium, in another stainless steel tank. Helium is injected into the gap between the steel propellant tank and the bladder to squeeze the propellant out. This was done with MMH and N2O4 tanks for thruster quads of the Apollo service module. Those tanks used silicone bladders. I'm recommending PCTFE because LOX and LCH4 are cryogenic. Using a bladder in this way allows zero-G (or microgravity) propellant transfer, no need for an ullage thruster. The 3rd stage of Saturn V used small solid rockets as ullage thrusters to restart the main engine. That means the solid rockets provided just enough thrust to provide acceleration that caused propellant in the main tanks to settle to the bottom so pumps could feed that propellant into the main engine. The S-IVB stage uses a J-2 engine as it's main engine, and LOX/LH2 propellants. I do not believe PCTFE would remain flexible and viable at the temperature of LH2, but the web sites I linked seem to indicate PCTFE service temperature is sufficient for LOX and LCH4. For the 3rd stage of a Saturn V (the S-IVB stage), the engine ignited twice: first for final insertion into Earth orbit and circularization of said orbit, second for Trans-Lunar Injection (TLI). That meant 2 sets of ullage rockets. However, those ullage rockets only had to operate long enough to settle propellant in the main tanks sufficiently for pumps to take-up propellant and feed the main engine, then for main engine ignition. What we're talking about is propellant transfer. That requires sufficient time to completely transfer all propellant in the tanks. Operating an ullage motor that length of time would significantly alter vehicle orbit. It would also consume propellant, but using a bladder adds mass of the bladder and helium pressurant tank. Elon likes to talk about autogenous pressurization; in this case the tanker would require helium, but only the tanker.

tahanson43206,
Testing a PCTFE bladder for cryogenic propellant transfer is a simple small-scale test that can be done on the ground. Honeywell is the primary manufacturer in the US. Daikin makes it in Japan. There are a number of resellers. It's not hard to get. I talked to someone from X-Core in 2005. They were developing a carbon fibre tank for liquid oxygen. To ensure it wasn't flammable, they lined it with a fluoropolymer. When I asked him which polymer, he said they chose the best one from Dupont. So I responded that would be Telfon-FEP. His jaw dropped. I also said PCTFE is made by Honeywell, it can handle colder temperatures and is more impermeable to oxygen, although it is more expensive. As a liner, their application did not require the polymer to remain flexible. But they may be interested in doing this work. I suppose I could purchase some equipment and do the test myself, but SpaceX could do it as well, why would they pay me?

tahanson43206 · 2023-05-22 14:35:54

For Calliban re #166

After reading (and re-reading) your post, it occurred to me that the piston idea might work well in the refueling facility, to deliver liquids to arriving space craft. Dr. Johnson's idea was to rotate the delivery container to flush liquid out of the interior. The advantage of this idea is that no additional mass is required for the vehicle that delivers fuel or oxidizer to the refueling facility. Since mass that does not contribute to the goal is undesirable, the rotating system would appear (to me at least) to be ideal for delivery.

On the other hand, your piston suggestion might be ideal for the refueling station to pump fuel and oxidizer into the departing vehicle at maximum speed. The concept that came to me is that the refueling station does NOT need a fallible seal at the rim of the piston. Fuel or oxidizer may be allowed to escape past the piston rim without causing any difficulty whatsoever. The reason is that the supply tank will always be larger than the receiving vessel tank, so any liquid that flows past the rim of the piston isn't going anywhere. It'll be right there in the supply tank when the receiving vessel is topped off.

The piston can be slowly drawn back to the starting point, and the supply tank refilled from an arriving tanker which would use the rotating technique to empty it's contents into the supply tank.

(th)

kbd512 · 2023-05-22 16:45:09

RobertDyck,

Thanks for the more complete explanation. I think it's a good idea. A piston would only work with a completely cylindrical tank with a very smooth interior and some way to account for thermal expansion and contraction. Perhaps that is doable, but it will be more complex than a bladder and a tank with spherical end caps is not optimized for syringe action. I don't really like the ullage motor solution, or centrifuging for that matter. There's too much that can go badly wrong with those solutions, because it moves one or both vehicles while they need to maintain precise attitude and distance from the tanker. Sloshing around 150t of propellant is not what I had in mind.

Calliban · 2023-05-23 01:46:01

kbd512 wrote:

RobertDyck,
Thanks for the more complete explanation. I think it's a good idea. A piston would only work with a completely cylindrical tank with a very smooth interior and some way to account for thermal expansion and contraction. Perhaps that is doable, but it will be more complex than a bladder and a tank with spherical end caps is not optimized for syringe action. I don't really like the ullage motor solution, or centrifuging for that matter. There's too much that can go badly wrong with those solutions, because it moves one or both vehicles while they need to maintain precise attitude and distance from the tanker. Sloshing around 150t of propellant is not what I had in mind.

Agreed. I think a syringe is problematic, as it imposes unrealistic geometry requirements on the tank. I thought I would throw it into the mix for completeness.

Using rotation, we only need enough gravity to settle the tanks. Differentiontial pressurisation can then be used to push propellant between tanks. So we are probably talking only a small fraction of 1g. The thing it has going for it is avoidance of cryogenic flexibles. A bladder obviates the need for rotation. As with all engineering decisions, it needs proper analysis of pros and conssuppirted by cost analysis and risk analysis.

tahanson43206 · 2023-05-23 06:13:58

For Calliban re #170

I'm sure you are aware of the difference, but for the sake of completeness of the presentation for any readers we might have, there are two forms of rotation for propellant transfer. One is end over end rotation. The other is rotation around the long axis of the tank, which is the solution recommended by GW Johnson, and about which he wrote a paper. That paper was printed and mailed to SpaceX, but since it was just one of (probably thousands) of unsolicited proposals they receive, the paper was not acknowledged.

The paper may have been published for viewing by NewMars members, but I no longer remember the details of activity around the time the paper was being prepared.

I will repeat that I think the piston solution has great potential value in a fuel depot, where leakage around the rim of the piston is of no consequence.

Rotation of arriving tankers (around the longitudinal axis) would facilitate removal of every last molecule of propellant from the tanker, while the piston solution would facilitate rapid refilling of vessels to be fueled from the refueling station.

A detail from Dr. Johnson's work that I no longer remember is how fluid is transferred from the rotating tanker to the non-rotating fuel station. There would be some clever engineering there, I suspect.

(th)

GW Johnson · 2023-05-23 09:48:27

What I finally came up with is tanks docked to the depot station. The tanker (or receiving) ship docks to the tank, then ship-and-tank undock from the depot station. You move a short distance off for safety, then spin up like a rifle bullet. Either pumps or differential pressure can drive the transfer flow. All you need is sump drains along the periphery to do this. Once transferred, ship-and-tank re-dock with the station, probably done by the station crew with handling arms, since they can see the actual docking hardware much better. Ship undocks from re-docked tank, and goes on its way. That's about as simple as I could come up with.

GW

tahanson43206 · 2023-05-23 11:20:18

For GW Johnson re #172

I just started a topic specifically dedicated to orbital refueling using rotation of the delivery tank around it's longitudinal axis.

Please consider adding posts to that topic with details of your proposal, and as much of the official paper as you are willing to publish.

I've added a variation that may (or may not) be practical.

Your proposal is to rotate the physical structure of the tank and that seems to me highly likely to work well.

A variation that may (or may not) work, is to rotate the fluid inside the delivery tank through some mechanism to be determined.

A physical rotation mechanism might be a post that runs the length of the tank, fitted with vanes that move the propellant around the interior of the tank.

This post and the vanes would add to the mass of the vehicle, but the tradeoff is simplicity of operations at the refueling station.

(th)

Mars_B4_Moon · 2023-09-11 18:39:31

FAA Closes SpaceX Starship Mishap Investigation

https://nasawatch.com/commercialization … stigation/

New Mars Forums

Announcement

#151 2023-05-16 16:07:34

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#152 2023-05-16 18:51:36

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#153 2023-05-17 07:33:03

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#154 2023-05-17 09:12:10

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#155 2023-05-17 09:25:59

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#156 2023-05-17 11:13:02

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#157 2023-05-17 13:41:19

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#158 2023-05-17 19:00:31

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#159 2023-05-18 15:01:36

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#160 2023-05-19 15:06:55

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#161 2023-05-19 15:33:32

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#162 2023-05-22 07:28:10

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#163 2023-05-22 07:46:21

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#164 2023-05-22 09:10:42

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#165 2023-05-22 11:38:05

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#166 2023-05-22 13:15:56

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#167 2023-05-22 14:31:43

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#168 2023-05-22 14:35:54

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#169 2023-05-22 16:45:09

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#170 2023-05-23 01:46:01

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#171 2023-05-23 06:13:58

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#172 2023-05-23 09:48:27

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#173 2023-05-23 11:20:18

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

#174 2023-09-11 18:39:31

Re: SuperHeavy+Starship have the thermal energy of the Hiroshima bomb.

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