Tsiolkovsky’all

SpaceX playing soccer with COPVs and then bolting them on the vehicle doesn’t feel like a more comforting answer but I agree it’s one I didn’t list. Not sure I understand why people would be rattling around inside the vehicle after a single engine test and then not re-running the single engine for a regression test.

/shrug, still you’re right. Unreported damage post-installation would totally do this, it’s just not a root cause I’ve seen. Would speak to a breakdown in safety culture for my folks, not sure what the safety culture looks like on the Starship line.

Oh c’mon.

Cannot possibly spin “blew up randomly during test prep” as a positive outcome. They probably don’t know how not to build that specific one unless they happened to instrument the faulty prop system components - they know that it failed but likely not why or how to fix it.

All evidence points to Starship having a super-finicky MPS that fails on the regular… which probably means they’re chasing performance by removing mass from the MPS and tank structure… which means either this design doesn’t work (totally possible) or that the as-built performance falls short of what was promised.

If you want to stan for Musk, I guess everyone has a type and I’m not going to shame you over it… but blowing up during test prep is not a good news story.

Maybe. Regardless, problem either in design or build.

Designing under-reinforced tanks indicates that the design can’t make payload and they’re cutting too far into structure allocations to make up for it.

Rupture could also be poor materials (sign of Boeing-style disregard for standards and safety) or a bad weld (same plus maybe training issues on the line). Means they’re running bad QA/QC protocols if the faulty material/construction made it to flight.

Chasing performance at the cost of safety sounds right down Musk’s alley.

Got it.

Space weather is weather - just like on Earth, it’s subject to so many unknowns and unknowable that reliable predictions are somewhere between really hard and totally impossible.

So - on Earth we don’t try to predict the exact weather that a given building is going to experience before we build it - that’d be super hard. Instead, we look at the rational maximum based on what we have seen and add some on top as a margin of safety… and that’s where we get building codes. Same applies in space - we make some measurements and add a factor of safety to cover our uncertainty. We have the same idea of building standards for pretty much everything except, to some extent, radiation.

The problem is that nobody has really found a workable solution for radiation shielding other than the EM shielding effects of large planetary bodies (see: Earth) or “thick shells of dense mass between the sensitive stuff and the outside.” Dense dumb mass is obviously not a great answer because of the launch cost - some have proposed using water, but you’d need a lot to provide adequate shielding… basically, you need a thick enough shell to match the wavelength of whatever radiation you’re shielding from.

I saw something kinda cool at AIAA Ascend from I think UMich that was proposing to basically pump enough electricity into space that the EM field would generate radiation shielding, but that’s like TRL 0 and electricity is also not always easy to come by.

Anyways, since there’s not a good answer for handling radiation, there’s no “building code” and the level of precision on the radiation level experienced is kinda irrelevant from an engineering standpoint. We can’t effectively protect against any amount, so if it’s >0, we have a problem.

I’d also suggest that from a “routinization” perspective you want a consistent building code, not a precise answer - because weather changes over time.

Both things exist, certainly, but I’m not sure how I’d establish a common unit to describe a set of things that are mostly waves but with a few particles thrown in. It’d have to be some kind of total energy flux through a selected region of space for a given time, and it’d be super specific to both the region and the timeframe since a CME event at the wrong time would really skew your results… I guess it could be some kind of time-average? So the thing you’d need is a total annual average energy flux of both EM and particle radiation through a region of interest. Such a thing certainly could (and probably has) been measured, but I don’t think I’ve ever seen it all combined. This is maybe a start? It at least has all the radiation information in one spot.

I’m not sure I understand the value proposition of having that kind of information if someone took the time to do it, but it’s a fun thing to think about.

So - there are two sources of radiation we think about. There’s radiation from our local bodies - mostly the Sun. The Sun radiates at least some across the entire electromagnetic spectrum, so the trivial answer to your question is “all radiation exists in space to some extent.” There’s also a general “cosmic radiation background” that is (we think) left over from the big bang. That radiation also spans the entire EM spectrum, but at a different distribution to what our Sun emits.

I’m guessing that the trivial answer of “all of it” isn’t what you want and it might be why you’re struggling to find the info you’re searching. Is there a more specific way to formulate your question?

Photo from earlier in the unloading process.

It’s the odds-on favorite for the next generation of radiation-hardened space computers (HPSC). Potential to be a 25x improvement over current capabilities. Guessing most of the use cases will be niche like that, but who knows.

The Starship concept of operations requires 11 launches for each mission to the moon - one for the vehicle, another 10 to refuel it once it get into earth orbit. Each of these missions have to autonomously dock and perform a cryogenic fuel transfer.

Nobody, and I mean nobody, has shown an operationally-viable in-space cryo transfer. Even doing it on Earth is a fussy thing - cryo transfer was behind two of the Artemis I scrubs, and NASA’s been doing it since Apollo.

Getting one Starship into orbit is an interesting milestone but it’s a long way from what they promised the world they could do… and the clock is ticking.

Eric Burger has been against SLS for like 15 years, it’s his whole schtick. Loves making points about how expensive it is, about how late it was, and that it means NASA can’t design rockets anymore. Never talks the other side - how Congress hamstrung the design, how it was consistently under-funded, and how it was shackled to Boeing at the same time that the entire company hit the skids.

SLS was forced to be a Frankenstein rocket slash jobs program by legislative fiat. Of course it’s not sustainable in a financially-constrained environment - it was designed to spread money and jobs just as much as it was designed to deliver payloads.

It’s still the only thing that can put an Orion vehicle in orbit, and Orion is the only vehicle we’ve got today that can get crew off the earth and to lunar orbit, and Artemis I was a masterpiece launch of a first-build rocket.

Another SLS hit piece from Ars Technica isn’t news, it’s just noise.

I call shenanigans. A fully autonomous space vehicle is three miracles away - we need a revolution in avionics to get systems capable of running computationally-expensive models, a revolution in sensor technology to allow for dense state knowledge of satellite systems without blowing mass and volume budgets, and we need a revolution in AI/ML that makes onboard collision avoidance and system upkeep viable.

I do believe that someone has pre-trained a model on vegetation and terrain features, has put that model up on a cube sat, and is using it to “autonomously” identify features of interest. I do believe someone has duct-taped a LLM to the ground systems to allow for voice interaction. I do not agree that those features indicate a high level of autonomy on the spacecraft.