Rocket engines can’t throttle down very much. Raptor can go down to 40% of its rated thrust, which for V3 would be 100 tons. The ship’s mass is maybe 150 tons with remaining propellant at the start of the landing burn, and probably around 100 tons at the end of the burn. Even at the lowest throttle, three engines would give it a thrust to weight ratio of 2, making hovering impossible and a suicide burn tricky. Two engines gives them redundancy, roll control, and a lower thrust to weight ratio to help with landing precision.
I’m surprised they went down to one engine at the end, because that means they lose most of their roll control. The only way to roll with one engine is to use the cold gas thrusters, which aren’t nearly as powerful.
They have a new RCS system on V3 which appeared to be hot gas thrusters. The landing was 3 engines lit to 2 to 1, using the lesson learned in very early flights to have an extra engine in case one fails unexpectedly.
Just FYI the sizes of the planets, stars, and their orbits are not to scale at all. To get an idea of how empty space is, there are 63,360 inches in a mile, and 63,239 astronomical units in a light-year. So if you scaled everything down such that Earth was 1 inch from the Sun, Neptune would be 30 inches away and Alpha Centauri would be 4 miles away.
If you were using a 4k display and had the Sun and Alpha Centauri visible at opposite sides of the display, the orbit of Neptune would be in the same pixel as the Sun.
There is a Wikipedia List (German) [1] of quite a few of those (in Germany and in other countries). I stumbled upon it, while trying to find a link to the one in my home town I have wandered quite a few times, as I lived between Neptun and Pluto (it was built before Pluto was demoted), very close to Pluto. It ran the street I grew up in and was built to scale (1:4 bln scale) by a teacher who was a full blown astro nerd and in his free time taught quite a few of the local youth about space, planets, the science behind it, but also built rockets with us and let them fly.
I so fondly remember him, as he was one of those people being a massive inspiration to my life.
That looks really cool! I've visited scale models of the solar system in Eugene, Oregon[1] and Norwich, Vermont[2], but neither one is anywhere near that size.
You are technically correct, the best kind of correct. However! That would be a terrible UX/UI experience. While showing distances on a linear scale is accurate, it fails to capture all the information a person in an interstellar ship may wish to see.
Something like logarithmic distances would better capture information like "Am I about to crash into the star or enter a nice orbit" while still showing the full picture of where you are in relation to where you're going and where you came from.
No idea of that's what happened here, just a thought, I'm not an expert in starship computer interface design.
Mercury is orbiting partially inside the Sun, and Jupiter is nearly as wide as the Sun when it should be 1/10 as much, so the planet nodes should be scaled down 10x relative to the Sun.
Also, I did a top-down pixel measurement, where I could see the distance to Tau Ceti as well as the orbit of Neptune. The radius of Neptune's orbit was 32px, while the distance to Tau Ceti was 1152px, for a ratio of 36, when in reality, Tau Ceti is 11.9 ly away, while Neptune has an orbit radius of 30 AU, which means Tau Ceti is around 25,000 Neptune orbits away, so the planet orbit scale is too big (or distance to other stars too small) by a factor of ~694 (25000/36)
Edit: Since this was top-down, the vertical displacement didn't factor into the distance, which also contributed to Tau Ceti appearing too close on screen, so the error is slightly better than that, maybe a factor of 600.
Edit 2:
Tau Ceti is rendered at 3.652 pc × 3 world units/pc = 10.956 world units
Neptune’s orbit radius is rendered as 30.05 AU × 0.0065 world units/AU = 0.195325 world units
The rendered ratio is 10.956 / 0.195325 = 56.09 Neptune-orbit radii
The real ratio should be 25,067.5 Neptune-orbit radii
Also, since we're nit-picking, the positions of the planets are not being updated in real time. For example, I know that Venus and Jupiter are currently approaching conjunction: there are spectacular views of them both at sunset right now here in the Southern Hemisphere!
Sure, but why does this need to be to scale. Isn't the point more to get the humans a way of understanding where things are relatively? Navigating the map makes it interesting in being able to interactively see where some of the stars are relative to each other. Seeing Regulus and Castor/Pollux from this perspective is much different than on terra firma.
It can't do that if it's not to scale! And who knows where the errors are? Neptune's orbit is way too big compared to Alpha Centauri. Are other stars also way too close compared to that? I can't stand these intentionally misleading education images of stuff. You have to work at undoing the artistic license of the author before it's useful.
We seem to be conflating the actual navigation computer with a display to show the humans information. If it were to scale, it would effectively be useless to the human as the scale of space is just too damn big to fit in some sort of navigation display. However, the actual navigation computer can be as accurate as necessary to not become Lost in Space. That's an entirely different franchise
I suspect this lack of scale on the planets was intentional from a usability perspective, because otherwise the planets be bits of dark dust that would be really hard to find. Jupiter has 11x more diameter than Earth and the Sun is 109x larger. When you consider the size of the solar system (including the Oort cloud) the Sun itself is bit a spec of tiny dust.
Even sci-fi writers that try to get this right have a hard time wrapping their heads around it.
"It's called space for a reason."
When I saw the series adaptation of The Expanse, it was really obvious they played a lot of artistic license to make it exciting. A real space battle would be dots firing invisible dots at each other. "Close quarter battle" would be within something like 2000 kilometers, maybe more. That is close.
> When I saw the series adaptation of The Expanse, it was really obvious they played a lot of artistic license to make it exciting. A real space battle would be dots firing invisible dots at each other. "Close quarter battle" would be within something like 2000 kilometers, maybe more. That is close.
This is noteworthy because The Expanse tried to get this better than other scifi, say Star Trek, Battlestar Galactica, or Star Wars (ok, space opera), where engagements take place at absurdly short ranges. In The Expanse you see the spaceships are really far apart, mostly dots to each other, and the engagements are (mostly) at really long torpedo ranges, with the exception of those cool scenes using PDCs. You get all those awesome shots where one spaceship sees the other as a tiny dot, then the camera zooms in dramatically to the other point of view. Cool!
And still, engagements are far too close range. But they "feel" long range in The Expanse, I think they got that visually right. I cannot blame them because I haven't seen anything any space combat in shows or movies that is even half as exciting and well done.
The Expanse also was (for me) the first to introduce the concept of a braking burn. Star Wars ships just stop without turning around - can’t unsee it. I think the way X-wing fighters “fly” also wouldn’t work at all, I don’t see any reaction mass coming out the sides.
Lucas wanted to make a swords and sorcery epic in space, and that’s what he did. And he wanted to make space battles look like WWII dogfights, so he did that too. There’s no point trying to compare Star Wars with any sort of realism.
Babylon 5 was the only show in the 90s that actually had any sort of physics based space combat (as opposed to Star Wars-style "they're really just airplanes but we're pretending it's space").
I really missed on watching Babylon 5 (it was during my time, but I unfortunately dismissed it as just another Star Trek wannabe, and only learned later this was unfair). I wish I had given it a chance. I cannot watch it now because of several reasons, and I'm not sure it would stand the test of time anyway, after having watched The Expanse.
Babylon 5 is at the beginning of the uncanny valley of computer graphics so it looks funny (I think they used Amigas) but if you pretend that those effects are of current cinema quality, everything else is good. They travel with hyperspace portals (maybe you saw Cowboy Bebop) so they don't have to perform many unphysical motions in normal space. It's still a great show. Less of a space opera compared to the Expanse, more like a Star Trek DS9 with ETs way more powerful than earthlings.
I was in a kind of similar situation. Didn't watch it when it was originally airing, though I could have. I eventually watched it decades later and absolutely loved it. That said, it was pre-The Expanse. But I still think it holds up pretty well, even if the special effects aren't as good.
I personally think B5 is a better show than The Expanse, but I don't mind the dated visuals or the occasional bit of campy acting or whatever. The storytelling is absolutely first-rate.
Biggest thing they all still get wrong for reasons of drama is showing humans wrestling with controls and flying like a fighter pilot. Real spaceships do not and will not have humans in the control loop except to specify a destination or target.
Yeah. Though they do have some nods towards realism, like how most combat systems are fully automated. PDCs fire automatically (at most they need a designated target, and for point defense they just fire), and even torpedos are assigned to targets using some touch screen and that's it, they are not fired using a joystick or similar nonsense.
The DPS-1 burn which restored the free return trajectory was done using the Apollo guidance computer.
The PC+2 burn which sped up the return from earth was done using the Apollo guidance computer.
The MCC-5 mid-course correction burn was done by hand.
The MCC-7 mid-course correction burn was done by hand, but used the Apollo guidance computer to integrate the accelerometer to let everyone know when the burn was done.
(All the burns on Apollo 8 were computer controlled. I'd assume Gemini 7 and 12 were hand flown, though I don't know for sure.)
Yes, even today it’s rare. Docking with the ISS or initiating the trans lunar burn on the most recent mission were all completely automated. The pilot arms the engine and authorizes it to proceed. I can imagine it being possible to grab the controls but it’s only done in exceptional or unusual cases.
Of course astronauts are trained for it in simulators in case computers fail.
If there are ever real space battles, that’s actually the most ridiculous time to have humans flying. Human reflexes and ability to mentally model 3D space under microgravity and orbital mechanics are just categorically inferior to what any machine can do. We are too slow and too imprecise.
If there are pilots at all it’ll be at a higher level, like the piloting equivalent of a programmer commanding AI bots. The computer will present the pilot with a digested real time tactical and strategic abstraction and the pilot would make decisions at that level.
A computer or avionics failure in a space battle would probably just be fatal. Which would mean EMP weapons against computers might factor in heavily.
That’s actually how the cons work in Star Trek (and many other SciFi shows too).
What officers do at the con once the ship is in motion is monitor ships systems and check for any external changes to the environment (such as other ships coming in for interception).
“Oh, come on. This is just great. An imperial Roman starship! . . . We know they lack sophisticated electronics, computers. I wonder how the hell they navigate that thing.”
“The drive isn’t always on,” said Titus.
Stef realized that a more precise translation of his words might have been, *The vulcans do not always vomit fire.*
“Every month they shut it down, and turn the ship.” He mimed this with his one good hand, like aligning a cannon. “The surveyors take sightings from the stars. Then they swivel the ship to make sure we’re on the right track, and fire up the drive again. It’s like laying a road, on the march. You lay a stretch, and at the end of the day the surveyors take their sightings to make sure you’re heading straight and true where you’re supposed to go, and the next day off you go. Works like a dream. Why, I remember once on campaign—”
“Navigation by dead reckoning,” said the ColU. “Taking sightings from the stars—simply pointing the craft at the destination. They have no computers here, Colonel Kalinski, nothing more complex than an abacus. And they have astrolabes, planispheres, orreries, sextants, and very fine clocks—all mechanical, mechanical, and remarkably sophisticated. But, Colonel, this starship is piloted using clockwork! However, if you have the brute energy of the kernels available, you don’t need subtlety, you don’t need fine control. You need only aim and fire.”
I seem to remember there was a scene where a human piloted Rocinante through a space station, using what looks like joystick controls and a large viewscreen in front of him.
> Star Trek, Battlestar Galactica, or Star Wars (ok, space opera), where engagements take place at absurdly short ranges.
I think that is we could maneuver spaceships like cars and get from place to place in seconds then we would engage at close distance. The only reason for keeping far away would be to have time to react to missile launches and attempt to intercept them. But that's not different than what ships do at sea.
>The only reason for keeping far away would be to have time to react to missile launches and attempt to intercept them. But that's not different than what ships do at sea.
Yes, that's why you would do it in space, too. The only reason sci-fi media doesn't do it is that it would look boring onscreen. You're just sitting there in the dark then all of a sudden a tungsten rod moving at some fraction of c vaporizes your hull, or a cloud of goo attaches to your hull and you bake to death slowly because you can't evaporate heat well enough. And of course actual lasers in a vaccuum are invisible.
Everything in space is so big, spaceships have to be so fast to get anywhere in a TV-friendly amount of time. I feel like spending an appreciable amount of time inside visual range would be like 2 enemy fighter jets pulling up next to each other so the pilots could sword fight. It really needs the deliberate cooperation of both parties. If anybody even breathes on their control stick they'll drop out of range instantaneously. Not that I'm complaining lol, I like to be able to see things in my TV shows.
Hitting debris at these velocities would be instant death. Debris comes from other vehicles (generally). You’d never want to be going where other people are, for safety.
But if your weapons outrange your enemy you will want to keep the range long. And if your weapons suffer less range penalty than theirs do you will want to keep the range long. The flip side being that if you're on the other side of either of these scenarios you want to keep the range short. And that's before you consider the effects of shielding--most universes with shields make them more effective against weaker attacks. This would mean that if you're facing lighter weapons than your own you keep the range open, if you're facing heavier ones you close.
There was one particularly egregious scene in The Mandalorian. The protagonist had to fly from Planet A to Planet B without hyperspace for reasons, and he was waylaid by some kind of space patrol, and then he just "turns the steering wheel sideways," and bam, he's landing on a different planet!
Even by Star Wars standard that was absurd. What is this, a highway chase scene?
The books are more realistic than the show. The show takes liberties to look cool, I think, which is okay. Not only does it mess with scale a lot but it also adds a lot of sound and visual effects that would not be there.
I recently read The Mote in God's Eye and its (much later) sequel The Gripping Hand, which had very interesting long-distance space combat scenes with high powered lasers - which only move at the speed of light. There's a very real "fog of war" element where you might be VERY out of date with what's happening just due to radio transmission speeds / direct observation.
That’s quite true. But even leaving that aside, most space battles are poorly written too. One of the best that I know of is the battle for Proxima from Babylon 5 (<https://www.youtube.com/watch?v=bE7lZv6LmrM>). This one is really good because we know why the battle is important, why the battle is going to happen here and not somewhere else, but most importantly we learn who the _people_ are (or at least the captains). They become characters, not just anonymous chits on a map.
Although the Expanse did well in some areas, it had no battles that were as well written or as memorable as this one.
All of those authors usually have to resort to the idea of "shipping lanes" so if the heroes are stranded between two planets eventually someone else will pass close to them on the way from one of those planets to the other one. This is wrong in a number of ways (first of all, they keep going anyway) but without that and without magically powerful fuels plots would be "they launched from Mars to Neptune, forget about them for the next three seasons, they'll be there at the beginning of the fourth one".
I thought orbital mechanics would still create those "shipping lanes" as the most efficient way to go from A to B. Of course with enough fuel you can go anywhere, but shipping specifically will love those reduced costs.
The problem is that the planets aren't standing still.
You want to do an optimum burn for Earth -> Mars? Compute an ellipse such that one end touches Earth's orbit, one end touches Mars' orbit. Oops, Mars isn't going to be there, you wait. Once every 26 months you will find that half an orbit later Mars will be there, then you burn. We call this a launch window.
26 months later they will line up again, but neither Earth nor Mars are where they were before. A spacecraft in this second window will never pass anywhere near a crippled spacecraft that flew in the first window. Nor could they do anything but send a report if it did happen--if you're doing efficient burns you don't have the fuel to go to somebody's aid.
“Space ... is big. Really big. You just won’t believe how vastly hugely mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist, but that’s just peanuts to space."
I don't think the Expanse authors were going for "hard sci-fi." There's, you know, fiction elements -- gates, aliens, magic. And the TV series is itself an adaptation of the books for a visual medium. Showing almost nothing would make for kind of boring TV combat.
Agreed. It's not "rock-hard sci-fi." It's "medium-hard sci-fi."
The background world building was pretty good from a hard SF point of view. Fusion rockets are possible and the high performance ones in the series are at the edge of physical plausibility but possible. Some of the details, like spinning up asteroids, don't work, but the basic physics of humanity's solar system build-out is mostly sound.
The rest of it gets increasingly soft and fantastic. Which is fine, it's fun space opera.
The issue is, and I believe the authors talk about this, is that the fusion torches they use are absolutely plausible, the problem is that theres no way those ships hold enough fuel for those trips, ripping the engines back out of plausibility again.
Right, they hand-wave this away with the "Epstein Drive"[0] (a name which I suppose has not aged well), which appears to somehow run on orders of magnitude less propellent than seems realistically possible.
> There's, you know, fiction elements -- gates, aliens, magic.
Setting aside magic, fictional science and technology aren't incompatible with hard sci-fi; in fact I'd argue that exploring those on "serious" terms is the entire point of the genre.
At some point I started seeing people advance this weird idea online that hard sci-fi means essentially nonfiction but that's not correct (or even sensible if you stop and think about it since at that point you're just writing a traditional character or political drama or whatever). It simply means taking a simulation style approach to various technological elements of the story. The deeper the simulation goes (ie the more nested levels of "okay and why does that work that way and what are the practical impacts on society") the "harder" the work is.
Magic is an interesting case. In theory it could be compatible with science but in practice the sort of phenomena that people usually mean by that term necessarily imply the intervention of some higher power.
Another comparison: if you count the "solar system" as ending at Neptune's orbit (obviously it extends much further, but just for the sake of comparison), then you could fit ~4465 "solar systems" in between our sun and the closest star, Proxima Centauri.
As I understand it, there is no consensus on the size of our solar system. We can measure the orbits of the planets, but it is much harder to measure where the Kuiper Belt or the Oort cloud ends. Estimates on both of those vary greatly.
They can build new boosters pretty quickly. New launch/catch towers take a lot longer, and they don't have any redundancy yet. Also they weren't going to reuse their V2 boosters once V3 was ready, so they could learn more by testing things like intentionally disabling an engine during the landing burn or flying at a higher angle of attack.
They won't use barges because the booster has no landing legs (to save weight), and because the booster is massive compared to Falcon 9. Also Starship is meant for rapid reusability, and it can take days to return a barge to port and unload the booster. Getting barge landings to work would be a distraction from the goal of Starship, and SpaceX already has Falcon 9 for current payloads.
And they won't attempt a catch with the first V3 booster because it's not worth the risk. They can build a new booster every couple of months. It takes much longer to build the launch/catch tower, and they don't have any spare towers yet. A catastrophe during a booster/ship catch would set them back a year, so they'll only attempt a catch if they're confident it will succeed.
That's because they use other terms like "Falcon 9/Heavy", "Starship", "Super Heavy", "launch vehicle/system", "booster", "upper/lower stage", and "spacecraft".
Hexavalent chromium can come from many industrial sources, including welding stainless steel. If you go to Tesla's lithium refinery in google maps[1] and follow the drainage ditch along highway 77 (to the northeast) about a half mile, you'll see a company called Tex-Isle Processing. They supply steel pipes and coating services for oil drilling.[2] It could be that one of their manufacturing processes creates hexavalent chromium.
In my opinion there isn't enough information to blame anyone for the slightly-above-drinking-water levels of hexavalent chromium. The drainage ditch goes along a highway and a rail line, so pollution could come from all kinds of places.
The lab tested for chromium in two ways: one test (ICP) measures all chromium of any kind, and the other measures hexavalent chromium specifically. The ICP test returned a concentration that was an order of magnitude smaller than the hexavalent test (0.0003 vs 0.0104 mg/L). That is to say, the tests contradict each other (because the whole is smaller than the part).
But I agree, measuring at the end of the ditch was the wrong thing to do if they take issue with that specific factory (though it was the right thing to do to prove a harmful pollution exists in general)
So another measurement directly at the pipe would be in order.
The measured levels of arsenic, strontium, and vanadium are below the limits for drinking water, even in California. And 4% of drinking water sources in California have higher hexavalent chromium content than the water in that ditch.[1] Besides sodium from salt, the only metal that was particularly high was lithium, at 0.0714mg/L or 71 micrograms per liter. A significant fraction of drinking water in the US has higher concentrations than that.[2]
The level of salt shouldn't affect much. Adding up the chloride and sodium content gets you 684mg/L, which is on the low end of brackish water (500-30,000mg/L). The limit for agricultural irrigation is 2,000mg/L, and photos of the pipe show plenty of grass growing around and in the water.
The phosphorous could come from fertilizers, as there's plenty of farm land in the area. That would also explain the higher ammonium levels, as both anhydrous ammonia and ammonium phosphate are common fertilizers.
The article is really about how sensitive our scientific instruments are, not how dangerous the water is. It reminds me of articles like Vice's American Honey Is Radioactive from Decades of Nuclear Bomb Testing[3], where the most radioactive honey they could find was 10 times less radioactive than a banana.
Different states have different rules about what sort of things insurers are allowed to charge different rates for. In the states that allow it, Tesla does offer insurance discounts for FSD usage.[1] Lemonade also offers discounts for FSD usage.[2]
In 2025, TriMet had 262 million passenger miles at a system cost of $812 million, for a cost of $3.09 per passenger mile.[1] Fares covered 7.8% of their costs. The other 92.2% came from payroll taxes and federal grants.
For comparison, a Lyft or Uber in the same area would cost you $1-2 per mile. Obviously it's not feasible for all 200k daily riders to take Uber/Lyft, and the Uber/Lyft cost doesn't include externalities like extra traffic, but TriMet is very expensive per passenger mile.
This is an implementation problem, not a problem with the underlying concept.
Public transit like buses and lightrail are significantly more efficient per person than personal vehicles. This is because they can transport many more people for the same amount of space and energy. They also typically run on set tracks, which yields more efficiency gains.
The US is really, really bad at doing public transit. It doesn't help that everything is car centric, which makes public transit much harder.
For example, in your comment you're excluding road cost, but you're including the full system cost of transit. That's a car centric side effect, e.g. we take roads for granted. But the cost of cars also includes the cost of roads, the cost of land under those roads, the cost of parking, etc.
The $812 million figure for 2025 did not include the cost to build the rail system. Nor did it include many other expenses. TriMet's expenditures for this year are $1.185 billion.[1]
If you divide passenger miles for TriMet busses (141,726,107) by the number of revenue miles (21,195,016), you get an average of 6.7 passengers per bus, or around 10% of available seats. For MAX (the train) you get an average of 27.4 passengers per train, or around 16% of available seats. In both cases that's seats, not total capacity including standing room. I realize it's important to provision the system for peak demand, but still this seems very wasteful.
And because road wear scales with the fourth power of axle loading, a bus will typically cause 1,000x more road damage than a car.[2] Assuming every car on the road has only one occupant, this means that, on average, a TriMet bus causes 150x more road wear per occupant. The main externality created by cars is traffic.
I agree with you that public transportation can work. It clearly does in many places. But Portland's public transportation is dysfunctional, and I don't see that changing any time soon. That's why substitutes (even partial substitutes like Waymo) are beneficial. The more options people have for getting around, the better off they'll be.
> This is an implementation problem, not a problem with the underlying concept.
I agree. The question remains - why do U.S. municipalities universally and repeatedly fail to successfully implement rapid transit at an efficient price point? Buses, trains, and subways in America have ever-growing budgets (both in absolute and per customer mile terms) with ever-declining quality of service. Just asking for more tax revenue again and again is not the solution.
The problem seems to be that many people view government services as a jobs program. Unfortunately, you can't maximize the number of well paying jobs a program creates AND provide high quality service AND control costs.
You raise a good point. My guess: It is not possible to provide what people need/want at a reasonable price point, especially in low density cities. As a result, it requires a lot of subsidies. I assume that cities create bus services primarily for people below middle class who may not be able to afford a car.
Re-read your same response, but replace "mass transit" with "private automobiles". The economic case is equally weak/negative. For a moment, imagine there is a small RaspberryPi-like device in your car that records every mile driven within city limits, then sends you a monthly bill for the true cost to maintain and police those roads. The cost would shock most users. Without a doubt, private automobiles are massively subsidised by tax payers. However, it is a democracy, and the voters are OK with it, so it continues.
To go further, there are very few mass transit systems in the world that do not require large gov't subsidies to operate. (I guess less than ten.) In all such cases, the gov't funds nearly 100% of the construction cost of railways.
> buses and lightrail are significantly more efficient per person than personal vehicles
Assuming the transit is fully utilized and the car is mostly not. And maybe that's a good way to look at it. But in Portland the light rail is often well under capacity, and in that case a carpool likely wins on efficiency.
> the cost of cars also includes the cost of roads, the cost of land under those roads, the cost of parking
Partially. Those roads will have to exist even if we did not have personal cars.
Right, the reason it might be underutilized is if you're bad at designing cities for it. Which the US is, so it is.
We design cities for cars, which results in the cities spreading out further and further, which makes transit less desirable and more expensive. Other countries don't have this problem to this degree, because they don't design their cities exclusively for cars.
Also, I don't think most roads would need to exist if the amount of cars decreased. Because of the density problem noted above. Cars are sort of self-eating. The more cars you use, the more land-per-car you need as everything spreads further out to accommodate the cars.
Consider that the transportation system might not be the best fit if it requires designing the rest of the world differently and against preferences (large, detached, single-family homes with a yard).
Those preferences are based at least partially on the available transportation. If the automobile didn't exist, would people still prefer to live so far from jobs and entertainment?
We also have the issue that dense inner cities are subsidizing the infrastructure for the spread out suburbs. If people had to pay the full cost they again might choose differently.
Train-advocates being against self-driving cars will be recognized as being equivalent to environmentalists being against nuclear power. Fortunately, I don't expect train-advocates as being nearly as successful. Once someone has tried Waymo, there's no going back to the old ways.
But you're ignoring the core point (in both your metaphor and in the argument at hand):
- If everyone took a Waymo... Waymo sucks. Not true of trains.
($/MW of power is stupid with nuclear in the age of solar and batteries, with basically zero safety concern... i.e. you can deploy solar and batteries to houses... not so much for nuclear)
I'm not against self driving cars. Self driving cars are an improvement over not self driving cars.
But self driving cars are not public transit. That's a grift that the people making the self driving cars are selling, so they can sell a bunch of self driving cars. The most prominent example is the hyperloop in vegas.
Self driving cars will not solve the traffic, safety, time, or cost concerns around cars. They will help a little bit, marginal gains. But they will not solve it because it's not a departure from the status quo, it's just a continuation of it.
Public transit is only efficient if people use it. If there’s only 1 person on the bus it is less efficient than a car.
Almost everyone drives so the government needs to pay for roads either way. Public transit on the other hand is easy to cut. What matters here is marginal costs of people using ride shares instead of public transit, not the full cost of driving that would need to be paid either way.
> Public transit like buses and lightrail are significantly more efficient per person than personal vehicles.
I would be interested to see a study on that. I see many buses driving around with zero or one passengers on them. If a bus is full, the efficiency would be off the charts. But for a city like Portland, that only happens during commute times. The rest of the time, the buses are driving around empty.
Partially not, as gas taxes cover part of it. I think gas and diesel taxes should cover the full cost of roads, which would help. Still doesn't mean transit should be run so inefficiently.
FWIW, some States require roads be funded exclusively with gas and use (e.g. vehicle registration) taxes. This does seem to significantly incentivize efficiency and long-term planning because their budget has to anticipate variable revenue.
Oh wow I didn't know Uber solely relied on private roads, had their own DMV, or fleet of millions of cars; truly an innovative company that doesn't rely on public infrastructure!
The point is that the cost of the road infrastructure isn't accounted for, not to mention the externality of having a half a million cars on the road to move 750k people. Rideshare is slipstreaming in the subsidized flow of cars.
I’m surprised they went down to one engine at the end, because that means they lose most of their roll control. The only way to roll with one engine is to use the cold gas thrusters, which aren’t nearly as powerful.
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