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Here's a page on stackexchange about reentry speed from Mars. It observes that SpaceX believes that arrival at Mars would be at 7.5 km/s, but the poster goes on to say that the return speed is going to be around 12 km/s - at best. Some returns put the speed at twice that. LEO reentry is 6.9...

That takes me back to the tile sheet approach. Create a sheet of a bunch of small tiles that are meshed together with wires or something, then install it as a unit against that stainless steel velcro surface. If a tile is damaged, peel off the entire section and lay a new one. Though I'm not...

What material like that won't ablate? If it's a ceramic paste, then it needs to be fired - which is why they have discrete tiles. It would be neat if the paste could be set strong enough to make it to orbit, then get fired properly during reentry. What about repairs? Chip out the stuff...

Do you mean like kitchen tile sheets being secured to a wall with grout? I'm trying to understand the combination of epoxy, honeycomb and mechanical. Is the epoxy intended to work like Loctite on the mechanical attachment?

It was believed to be an interim patch because Robotaxis were only a year away. Why devote a lot of time and energy to something you're going to obsolete? I just hope it's clear to everyone at Tesla that our cars are going to stay at L2 (perhaps with excursions into L3), and that they need a...

I assume the system is just repeating its training. It wasn't shown many examples of proceeding without any traffic, so it has low confidence as to whether or not to go. On the other hand, it was shown countless examples of the more difficult case of turning before or after other cars. So it...

It begs the question of what the loss rate would be for ships without the additional protection. I also wonder about the volume of debris being dumped on points west of the Cape. Thirty eight percent of Space Shuttle Columbia was recovered, and that vehicle wasn't made of stainless steel. I...

And while we were all keeping an eye on IFT-4 developments, they removed everything suborbital from the launch site, and also completed the static fire stand with its support equipment over at the Massey's site. Still no word on when they'll try a first static fire.

Weird. Not sure where I went wrong there. You're correct. If 100 tons of landing mass, it'll need 200 tons of propellant. If 200 tons of landing mass, it'll need 400 tons of propellant. I like it. I'm reminded of a wall of ivy. It either goes as a single sheet or not at all. And, in ivy...

Ooo! Ooo! Delta-v question! Assume a 100 ton ship and 100 tons of cargo. It would need ~100 tons of propellant to reduce its velocity by 4166 m/s (15,000 km/h). If we can assume an empty ship of 100 tons mass, then it needs ~70 tons of propellant. Those final tons of propellant hit much...

It looks like the explosives for the flight termination system for each vehicle are being installed. On IFT-3, the explosives were installed six days before launch. June 5 is in 6 days. They've also moved the big crane away from the tower, but I can't tell how far. It's no longer in shot...

Irresponsible users ruin the roads for everyone. I'm of the opinion that the detection system should be full time, and that inattention should result in an escalating series of feature losses to the car. One strike and you lose the car's entertainment features. Two strikes and your heating...

I think "most places" would imply "critical areas". Bursting a tank would mean the loss of structural integrity of the vehicle. I doubt there are many areas on the vehicle that could tolerate a tile-diameter plasma torch intruding into the interior. But it looks like we're going to get...

Road closures for flight testing activities have been ordered for June 5, 6, and 7.

The traffic visualization is V11 code, and routing is provided by a central service. So could V11 be actively visualizing the lanes, and V12 is maneuvering by the latest central data? I assume that the local map data is for the map visualization. It doesn't need updating very often. By this...

Nah. Perfect visibility. There was no reason to take that right, which is why I attributed it to map data. As I recall, the road was gently curving to the left at that point, so it may have decided that a safe right was better than any left at all. The map data is organized into segments, so...

I searched for "Tim Ellis complaint SpaceX", and got the same article at the New York Times and Seattle Times, with a third outlet (Yahoo News Canada) using the title but writing their own article. A fourth, The Daily Beast had this quote: As the CEO in Margin Call said, "Be First, Be...

Wet dress rehearsal complete. Currently detanking. This was a long one, where they left the vehicles fully tanked for roughly half an hour before the Detonation Suppression System (DSS) was triggered, signaling the end of the countdown. The NSF guys were puzzled by the long hold while tanked.

Another wet dress rehearsal is underway. Note that the countdown is for a Starlink launch.

I'm sure the system can tolerate some variation in the camera orientation, but if it's too far off for even a camera recalibration to sort it out you're probably best off taking it in to have service look at it. I doubt that they'd check the FSD performance, but they can check to see if the...

Are you seeing lane centering issues on interstate highways? My highway centering is always rock solid, but on secondary roads, the car wanders. That different is down to V11's heuristic approach versus V12's neural network approach.

The neural network processes all the pixels from all the cameras in order to figure out how to do anything. Which pixels have the greatest role to play for which tasks can only be known by tearing apart the neural network and watching which neurons are firing when performing each task. In...

It's a working assumption with the same confidence as "The sun will rise in the east tomorrow."

Well, they were tiled. Perhaps the surrounding steel burned through. Also, they're back to a stacked vehicle for IFT-4. Purty, ain't it? I think it'll look pretty awesome once they've removed all the upright tanks. The only significant vertical structure will be the tower and vehicle.

That was the Luddite tool of choice from the start.

Information. Propaganda. Lobbying. If it's superintelligent, then it will use our inherent susceptibilities to achieve its ends. Imagine a superintelligence that hints, cajoles and influences society in the direction of placing more and more critical devices online. Infrastructure...

What's your take on V12 crossing into oncoming lanes to go around parked cars and such? That's breaking the law purely out of convenience.

I think of it like this; humans have intelligence, and neural networks have trained instincts. I believe that it will take multiple discrete neural networks, each trained for a specific domain (e.g. planning, control, perception, etc) that will lead to something that we would consider...

I noticed that too. It sure looked like tiles covering those spots. Black hexagons.

Surprising no one, it's the same event. Here's a 2018 article with the same pictures, but cropped differently. https://radaronline.com/photos/brad-pitt-car-crash-wreck-accident-tesla-photos/

I assume that that's a pneumatic line to generate lots of suction, then they pull on the device until they hit the desire strain on the tile. Then they push a button, release the suction, and move on to the next one. They've been using the suction cup technique for a while. That's the fabric...

Here's the SpaceX page with the flight test timeline. It says that they'll jettison the hot staging ring two seconds after the end of the boostback burn. So they won't be relying on aerodynamic forces at all. As @mongo observes, if there are springs, they don't even have to be able to support...

It's my understanding that the cap is a work structure. That is, the vehicle doesn't launch with it. NSF observed that there were also plugs placed in the holes where the grid fins will be installed. So the attempt seems to be to seal the top of the booster from the elements. They may have...

I'd worry about the airflow fighting release during the flip, but I may be overestimating the density of the air. If they do it during the flip, it'll be quite a sight. Yeah, allowing airflow to pull the ring off is certainly something deserving of simulation. If they get into a cross-range...

It should be the reverse. The wake of the falling cylinder is an area of low pressure. If the air stream is hitting the leading face of the ring, then there would be higher pressure on that face, with lower pressure in the wake. It might be enough to pull it off once unlatched. They may just...

Pure speculation: the hot staging ring is throwing off the center of mass for the booster and screwing up the flight software. They may not want to muck with the flight software because the hot staging ring approach is a temporary solution. So they'll just throw it away - it's going to die...

In that scenario, the Methane is speculated to be freezing. As for autogenous pressurization, folks online debate how it's done, but it's clear that it's done without sending combustion byproducts into the tanks where they can freeze. Everyone agrees that's a non-starter.

Did you mean Methane? SpaceX is chilling the Methane to -180 C, and the Oxygen to -207 C. If any of the Methane leaks into the LOX tank, it'll freeze, right? Or were you thinking of freezing air?

Here's a page from the Shuttle's propulsion system components manual. Apparently, the filters on the Shuttle would pick up stuff like bits of tape, or metal particles and such. How do you sanitize a tank that large? For Starship, the web is obsessed with the idea of ice crystals forming and...

Fooled me again. I think I'll wait for launch license announcements from now on.

Ah, but I said "ramping up for mass production", not "ramping up to production".

I cut them a break on this. They're ramping up for mass production of rockets, and that's a new thing for them. It's gotta be a pretty cool sensation. The tragedy for me is that they're designed as expended vehicles. It's the single use plastic of the rocketry world.

Voice command. "Wipers off"

Make sure you insulate yourself from all news about it until you're ready to watch the replay. It'll be just as good.

SpaceX could go by position for the uncontested areas, then send a message to all others, informing the operators to send a message up a secure chain of command to reactivate their terminal. Russians would see the message, but have no recourse to activating their terminals. If SpaceX sees any...

No, it's a small vehicle. It's supposed to go up on a Falcon 9 next year. https://en.wikipedia.org/wiki/Haven-1

Vast's Haven 1 space station now has a pathfinder article.

Nor does FSD start on its own. The consequences of starting FSD are vastly more involved than a gun, but it remains a machine. Assuming that it was essentially impossible for a car to avoid the child, yes. If people believe that it could have been avoided, then it would be treated as a...

Are there any situations where you'd accept a gun killing a human? A computer has no agency. All we have is a machine with a more remote sense of control compared to something like a gun. The neural network will deterministically do exactly what it is trained to do, just like a gun does when...

Notice to Mariners is up. That's confirmation enough for me to believe. This is the resource I use to follow preparations: https://nextspaceflight.com/starship/