I mean, normally green stars aren't real, to the human eye. The problem is that from a standard blackbody curve, as you go up in surface temperature, by the time you've flipped the red-green cone activation ratio to the green side, you're getting so much blue that it looks like white instead. And then if you keep going, blue dominates and it turns blue. So it goes red, yellow, white, blue, not stopping for green. You also don't get purple because, for the most part, purple needs a strong red activation, little green, alongside at least a reasonable amount of blue - but with stars, the blue is way stronger than the red under a typical blackbody curve (there actually is a small shortwave red activation peak, so you *can* get purple purely with shortwave (like in a rainbow), but in the blackbody spectrum, the blue is so dominant that its not enough).

The trick here is that specific emission and absorption spectra can deviate from a standard blackbody curve. It may seem weird because one is used to sodium emission lamps being orange. But in the star's ~4000K photosphere, pressure broadening smears out the sodium doublet into a massive absorption trough, absorbing red to yellow light. Accreted calcium also has a similar effect on the blue side of the spectrum. Look back at the 4000K blackbody curve in the above link, imagine even a relatively minor suppression in both red and blue, and you can see how it morphs into a curve that the eye will read as green. :)

Well, thanks to what we learned from the IAU in the Pluto debacle, where "dwarf planets" are not classified as planets, I look forward to dwarf stars not even being classified as stars soon enough ;) And wait until dwarf galaxies get kicked out of the galaxy club! ;)

There's a grate on the bottom that keeps out big debris. Small debris isn't great for the fan, but it's even worse for the car behind you.

The car has onboard compressors (fills from the rear).
Very loud with the fan, extremely loud with the rockets.
You get blasted with hurricane-force winds.

Fan cars, like rockets, are too noisy and have too much debris risk for normal roads. Both fans and rockets will have to be locked behind a track mode, with the possible exception of in emergencies / AEB, where things like noise and debris hazards are generally waived if it can help prevent or ameliorate an accident.

Depends on how big the rounds are and how far away they're fired from.

They don't float though. Sounds like Elon kept pushing and pushing the engineers on that one and they just could not deliver in any sort of way that would keep practical as an actual car. I wonder how much money they burned trying...

That compares to the OP's claim that the car is CG how?

I'd also add to CAIMLAS's list about how to make the exhaust gas travel so quickly away from the car and form sustained mach diamonds if they're not actual thrusters with choked supersonic jets

The car has onboard compressors, of course.

10-15 seconds available of a couple Gs of thrust should have no problems. Even if total thrust is only 2G (and remember, they have the bottom fans too) - just 1G beyond gravity - I calculate it should only take about 4 seconds of counterthrust to stop from terminal velocity (if the car's flight is kept with the bottom oriented toward the airflow, that is).

If the car had a radar that could let it accurately estimate time to collision, it should be able to arrest pretty much any fall safely.

The tanks are powered by an onboard compressor, powered by the battery pack; you don't have to find "a place" with a compressor to recharge them. Air intakes are at the rear. No word on how long they take to refill, but I would imagine 1-3 minutes. And I imagine you probably have ~15-20 seconds of thruster power before pressure drops enough that the thrusters are no longer choked and their thrust collapses (and thrust will steadily drop even before then). TL/DR, it's a jumping car, not a flying car.

Obviously, all of these features need to be locked behind a "track mode", like other features that are illegal on normal roads. That said, they could probably get an exemption for "emergency features" (AEB and the like).

Ion thrusters are extremely low thrust and take an extremely large amount of power per unit thrust. They're for mass-efficiency. But we don't care about mass efficiency here, we have an atmosphere.

This version has always been described as the "SpaceX Options Package". It's supposed to be more expensive than the standard version, which is supposed to have a back seat instead of the COPV. No comment about whether the standard one would also be a fan car. The fan assembly is where much of the battery pack would normally go. If they were to make a non-COPV, non-fan version, it could have plenty of range. My bet is that this one's range is limited (though not tiny - ultimately, you still need a lot of power - and pack size directly relates to pack power output - for them to be able to set the sorts of track records that they want to)

But since they didn't bring up the standard Roadster at all here, who knows if that's even still supposed to be a thing?

60 seconds would be a godsend - they never showed it operating for more than like 10 seconds. It's a hopping car, not a flying car.

That said, it probably *is* streetlegal in the US (barring state laws) if the rocket and fan-car functionality is locked behind a "Track Mode" wall. And if they wanted to they probably could get permission to use the cold gas thrusters and fan in an emergency accident-avoidance / AEB scenario (normal restrictions like noise, debris, etc) get readily waived in the interest of avoiding crashes or reducing injury risk. E.g., firing an airbag is anything but quiet, but that's not relevant to normal noise regs. Also, even noncompliant supercars (including fan cars) can generally get a "show and display" exemption in the US, which lets the vehicle be driven up to 2500 miles per year.

Don't expect this to pass muster in Europe, of course.

(Note that normally rocket cars are flatly illegal, as sufficiently large rockets count as "explosive devices" and require an ATF permit. But that doesn't apply to cold gas thrusters, as they do not involve combustion)

Yeah, that latter one basically focused on the fact the output looked verbatim like the 'training' material, so the judgement was that AI was more an excuse than a demonstrable transformative thing.

Note in some other case I recall the AI company arguing that the ingest and training of material is 'transformative' but the engines could be used to violate copyright, but then the *operator* would be on the hook for infringement, as the operator supplied the prompt that resulted in infringement.

There was also that OpenAI deal with Disney that was going to let Disney characters be used in OpenAI output but that got dropped. Lots of mixed assumptions in play with the AI companies asserting that they don't need permission, getting permission or forcing permission anyway, and shifting responsibility to the users.

Even if it exactly works as advertised, if you thought a rock kicked up by a tire was bad, just wait....

about Uber itself here. But as some minor trivia about Manchester: the "Man" comes from "Mamm", meaning "breast", referencing a small breast-shaped hill that used to be located in what's now the Castlewood district (it's since been lost).

The name of the city basically means "Tit Fort".