marze

"Tesla, where we make the impossible late"

Astrophysics

If China had "no regulations" and was building out 100% coal, no one would be worrying that China industry would have an advantage due to low electricity cost vs rest of world.

So I haven't looked through the comments, and assume this has been discussed, but the simple solution is to limit contracts to, say, $4M, and pay only on successful completion. Then build a large project through a series of smaller steps.

I was interested to learn recently that Alan Turing believed telepathy was a real thing. At least that is what someone wrote.

To me, the interesting question is, were they the first to come up with the concept of communicating while jumping around on a random-like sequence of frequencies. What was the prior art?

It may have been 15 minutes to both go down and explore, it mentioned 4 minutes at the bottom. The quote: "15-minute descent and exploration"

It will be interesting to see who owns all the compute hardware in a few years, that cost billions now, and what becomes of it. With an expected useful lifetime so short the depreciation rate is insane.

I find the article unconvincing, although I'm open to being convinced. With historical hindsight, it should be easy to see if the Lamarr et al patent seems novel. Just because an examiner doesn't allow a claim, I don't see that as strong evidence it wasn't novel at the time. They always are rejecting claims, sometime for good reason, sometimes not.

A more convincing article would focus on purported prior art patents, and let the reader judge if really anticipated frequency hopping.

It might just be that there are a lot more cheap pizza locations than fancy ones.

This fellow also stays with friends.

My brother has a friend who is the modern day equivalent. He travels North America by bike, eats pizza from cheap pizza restaurant dumpsters.

Once there are 50M electric cars parked here and there, the solution will be even more obvious.

Also, it took 10 and 14 seconds to switch them back on. If it was an accidental switch, you would think it would have been quicker to switch them back.

You mention "brain fart". There is certainly a long history of pilots selecting the wrong lever, or wrong switch. So, it is possible the pilot who denied switching the fuel off thought he had switched something else.

As in, "an electric vehicle fleet that charges during the day and powers the grid at night if the owner opts in"?

Transmission lines are a interesting idea, but expensive.

Once solar is cheap (like now, as it already is), you can put in 3x what is needed on a sunny day, and power everything on cloudy days. Solar runs on cloudy days. Night obviously requires a different solution. Start by installing solar over all parking lots.

To think that you won't be able to run a 100% solar/wind grid is a bet against human ingenuity. If generation in excess of peak demand was installed of solar/wind, there are many promising approaches to deal with generation shortfalls. Batteries, load shifting, an electric vehicle fleet that charges during the day and powers the grid at night if the owner opts in, precooling a home with AC during the day to a low set point so AC isn't needed at night, H2 storage in salt caverns, pumped hydro, aluminum smelters that operate during excess power periods, the possibilities are infinite.

It won't be hard. Don't bet against human ingenuity.

Against the cost of a lower payload fraction. Say you get 4% with TSTO, 2% with SSTO. And if you run into trouble with the design, the SSTO payload moves towards 0%. Your operational savings need to compensate for a doubling of cost per unit mass payload, possibly much more.

And even though full reusability is much easier with two stages, and has not been achieved yet.

References?

Wasn't a correlation with elderly drivers and the unintended accretion found in the Toyota cases?

A legal mandate should be made to require this on all motorbikes.

Oops, you're right!

So legacy launch vehicles with the exception of Shuttle lift of leisurely.

That is incorrect. Shuttle liftoff thrust was 5.7 million pounds, giving a ratio of 1.25.

At liftoff, each SRB produces 2.65 million pounds thrust [1]. Using Wikipedia numbers instead (2.8 million pounds for SRB thrust at liftoff [2]) gives a liftoff thrust to weight ratio of 1.33. The 3xSME produce 0.4 million pounds thrust at liftoff. The SRB thrust did increase as the burn progressed, then ramped down for max Q.

People are accustomed to SpaceX rockets rapid acceleration, since they conduct most launches these days, but historic rockets (and New Glenn) accelerated more slowly off the pad.

[1] https://www.nasa.gov/reference/the-space-shuttle/

[2] https://en.wikipedia.org/wiki/Space_Shuttle_Solid_Rocket_Boo...

Historic rockets around 1.2, including Shuttle, check your numbers. Starship is not a "historic rocket". It and Falcon 9 fly a trajectory that is optimized for something else, not max payload for a set first stage thrust.

That is a trajectory optimized for payload mass, with a set amount of first stage thrust. It is quite typical, historically. It just looks extra slow since the New Glenn rocket is quite enormous relative to historic rockets.

An impressive first flight by any measure!

This one looks fine to me from the outside:

https://x.com/camoPirate_xXx/status/1877749643465134141

Everyone with a fire-hardened house should be feeling good. If all Pacific Palisades houses were fire-hardened, the fire would have burned vegetation but few houses.

Even modest fire hardening would help. If a wood-frame house burns, it is a danger to all nearby houses. Hardening reduces the chain reaction potential.

One would certainly hope that reconstruction would involve houses with concrete exteriors, or masonry. It would be silly to build a bunch of wood houses. Especially for luxury homes, a concrete shell should only add 1% to the overall cost. And technology exists to build hurricane-proof houses.

Shouldn't this be mandated, if a "natural disaster" destroys a home, to not replace it with a similarly vulnerable structure?

Does anyone know if the insurance companies gave discounts to houses that had fire resistant improvements, in the areas that burned in these fires?

Probably a more pertinent question would be: can you construct houses that would not burn in a Santa Ana if all the vegetation and landscaping nearby burned.

If you have fire resistant structures and only vegetation burned, not any structures, it would be much less expensive to replace just the landscaping plants.

In a 80 mph wind, it would be very challenging to design a structure that would survive a wooden house burning next door.

Fire suppression and lack of controlled burns leads to big fires. However in an environment with hot Santa Ana Winds, even with good forest land fuel management, a city like Pacific Palisades as it stood could conceivably burn from an accidental fire within the city.

The real question is this: do we have the capability to build a house that would not burn down if the neighboring house caught fire? If so, a city could be build that would be impervious to wild fire, arson, and accidental fires.

How much would this cost?