RCgothic

Ah, but what if they built a test stand that could accurately represent dynamic flight conditions /s

1058 was the NASA worm marked booster. A sad loss. 19 flights was a great run. Still, there are three more boosters already on 17 flights, and a further 5 with more than ten.

Many months - as the video timestamp 11th July 2022. So sixteen months and change at this point. It was booster 7 which eventually flew on IFT-1 in April this year. Booster 9 flew on IFT-2. Booster 10 is currently in the launch prep sequence.

I must be thinking of a different X because it is not even close to cash positive, not on a trajectory to be, and is in substantially worse shape than it was before his takeover. Not only do the subscription model and staff firings not recoup even a fraction of the lost advertising revenue (lost for no good reason at all), but it has a heavy debt burden that's over a billion dollars per year and it's currently valued less than a third of what he paid for it. The total mismanagement has completely exploded his aura of competence and poses a direct threat to his control of his other companies SpaceX included. If Shotwell retained control it could even be an improvement.

I was a prodigious twitter user until it became X and witnessed firsthand his descent into echo-chamber and buying into his own trollish cult of personality. It has not been at all edifying, and his decisions related to the site have been almost purely destructive and he's now on the hook for billions a year in debt repayments. Something like 73% of his Tesla stock is leveraged, so if he has to sell any significant amount to cover his twitter debt or default on that debt then that could both crash the value of Tesla and cause banks to call in his collateral and he'll lose the company. It's a small step from there to having to sell his stake in SpaceX to cover debts. He's already previously borrowed $1B from SpaceX (albeit he paid it back quickly on that occasion).

I'm a lot more worried about the future of SpaceX thanks to Musk's behaviour and contagion from other businesses of his than I am about technical aspects of Starship. Technical difficulties can be solved, but there's no recent evidence Musk can keep his erratic behaviour from impacting his companies. Twitter's on a death spiral, and the debt is heavily leveraged against Tesla.

Eloquently put.

It's already even smarter than that. If an engine goes out it'll first gimbal the centre engines to maintain thrust through the centre of mass, and only down-throttle opposite engines if doing so is necessary to maintain sufficient margin of control authority. Actually turning opposite engines off would be a last resort.

There isn't any evidence the engines were the source of the issues on IFT-2, and even with the previous version of engines some of the failures on SN8 to 11 were not engine related. SN8 had a sudden loss of pressure in the methane header tank and SN10 had helium ingestion.

Uranium is really abundant in Earth's crust. More so than gold, mercury, silver and tin. There are traces basically everywhere that metals are found. Rocky inner solar system worlds in the Goldilocks zone are therefore overwhelmingly likely to have decent uranium deposits. If a previous civilization really had stripped a planet of all uranium, they'd likely have taken most of everything else of value as well. Icy worlds and the atmospheres of gas giants would be very metal deficient generally. As well as presenting an extremely hazardous environment for visiting lifeforms, it's unclear higher life could evolve in such places. Certainly nothing needing decent quantities of iron for blood.

https://amp.theguardian.com/science/2023/dec/09/space-orbit-mystery-international-space-station-tomato Missing tomato on ISS found 8 months after disappearance, astronaut Francisco Rubio exonerated of stealing and eating the tomato.

In this instance they could launch a 300t depot with over 200t of zero boil off gubbins and *zero* residual propellants and all it would cost is an additional refuelling mission. Obviously there's room to refine, but as a first effort they've got a lot of mass budget to play with.

Double layer tanks with vacuum between them and a solar powered cryo-cooler. Maybe a sunshade too. Refine as necessary. It's not as if zero-boil-off tanks are a theoretical impossibility.

It won t be Hydrogen. It'll be Oxygen or Methane which is what Starship has onboard already.

We have a perfectly operational falcon 9 and falcon heavy, and with appropriate mission architectures *those* make a nonsense of SLS. For the same expenditure as 1 SLS mission it would be possible to purchase 40 centre-core expended falcon heavy missions for about 2000t to LEO pure payload. Moreover that's commercial sale price, so those missions would generate enough profit for SpaceX to launch more Starlink missions and progress Starship. Whereas funds spent on SLS are not redeveloped. The only thing keeping SLS going at this point is stubbornness.

I don't see why the Artemis partner nations couldn't be just as bought in to a lunar surface base.

None of us like Gateway, but there isn't any cheap modification to SLS, and certainly not anything that would be as cheap or capable as simply moving Orion/ESM on top of a Starship Super Heavy stack. NASA should stop making bad puddings just because they've spent a long time preparing bad ingredients.

Propellant transfer is a milestone, true, a really important one. But demonstrating RVac apparently was a milestone as well, got there first on IFT-2.

Richard Branson to provide no more funding for Virgin Galactic, says it has enough, alarms investors, shares plummet. https://www.theguardian.com/science/2023/dec/04/virgin-galactic-shares-richard-branson-funding

And even if an engine exploded, it's not necessarily the fault of the engine. E.g. fuel starvation causing turbine overspeed, or the control system getting fragged by shrapnel from a pressurised line failing. SpaceX are the people with the data.

Traditional grids generate their power close to where it is needed, and long-distance power transmission is fractional amounts for rural purposes and load balancing. Decentralised grids to support unpredictable power sources need to be able to send large fractions of national consumption over long distances and have many more connection points. This also adds to the price per kWh, which will soon become apparent. Large nukes use fuel more efficiently than small nukes (it's a function of the surface area to lose neutrons from vs volume - another square cube law), but as fuel is a relatively small proportion of the lifetime costs this isn't necessarily a huge deal if you can make other savings with economies of scale on smaller plants, but this would rely on there being enough permissible nuclear sites. The current policy of reusing existing sites (in the UK at least), tends to favour large plants. Small plants close to where the power is needed would be particularly effective for using the by-product heat for heating and industrial process heat. By using this heat it's possible to triple the fuel efficiency of nuclear plants (any thermal plant actually). It's bizarre we don't do this already. Edit: It's even more bizarre 6 of you liked this post before I corrected all the word substitutions autocorrect snuck in that I didn't immediately notice yesterday. I'm amazed anyone understood what I was on about.

As someone who used to design wind turbines and is now designing a commercial fission plant for the upcoming nuclear renaissance, hard disagree. If you think wind and solar are cheap now, just keep giving them a bigger share of the grid and see what happens. As their share goes up, productivity drops due to oversupply and the price per kWh goes up massively. Nuclear is as cheap to build as anything else when you commit to having a lot and a lot cheaper than trying to transition entirely to wind and solar, or even worse continuing to burn carbon. Nuclear also has an enormously longer lifespan, is vastly more reliable, and uses far fewer resources and land. PWR nuclear plants are easy to decommission and spent nuclear fuel is such a valuable resource that it should be a crime to waste by burying it. Nobody has *ever* been seriously harmed by spent nuclear fuel from a commercial power plant, and if we absolutely must bury it it'd be no more dangerous to future generations than anything else we routinely put in industrial landfills, like mercury.

Requires reuse, definitely. A reused stage costs basically nothing per flight compared to a new one and F9 still expends S2 each flight, so if SS SH can manage full reuse it wins. Expendable vs expendable certainly there's no way Superheavy can come in under F9. It's over 4x the engines even if the structure breaks even for welded steel vs machined aluminium isogrid.

Not just lower per flight, single digit millions per flight. An order of magnitude less per flight and two orders of magnitude per kg.

Maybe, but that's doesn't appear to be what Scott's tweet says. The source of the apparent leak is speculation at this stage. Official update: https://www.spacex.com/launches/mission/?missionId=starship-flight-2 Booster was a RUD, ship was confirmed FTS triggered after loss of telemetry.