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DnD with the option to switch between 3rd and 1st person views would be amazing.

Personally, I'd like an NFL game where you drop your players on the line, draw the routes on the field, and then switch to 1st person QB view for the snap.


https://www.meta.com/experiences/nfl-pro-era/419397521067812...

NFL Pro Era for MQ3 sent chills up my spine when I first walked out into the arena.


Maybe I have seen too many court dramas, but a gas station near me painted their bollards this color, and it made me wonder if it might open them up to liability.

Nah, I don't think the bollards are considered signaling - it appears like they are often accompanied by light signals.

It's certainly better than cerulean blue.

Or open them up to producing hilarious videos.

https://x.com/WorldBollard


Covid & Flu A/B tests are in most drug stores these days and usually run about $5 more than covid only tests.

In Europe, they're currently even available for under a euro (or under two euros for a 'regular' expiry date and RSV as well) if you buy them online instead of at retail. For example [1] or [2] (I have no affiliation with the shop).

[1] https://altruan.de/products/safecare-covid19-influenza-a-b-a...

[2] https://altruan.de/products/fluorecare-kombischnelltest-rsv-...


"periodic eggs were placed alternatively in boiling water (Th = 100 °C) for th = 2 min and water at Tc = 30 °C for tc = 2 min, for a total cooking time of 32 minutes, which corresponds to the repetition of the hot and cold cycles for a total of N = 8 times. In the case of periodic eggs, a bowl filled with water kept at 30 °C was used for the cold cooking cycle."

I might try this later. The image looks like a great ramen egg.


I can soft boil eggs for ramen in about 4-6 minutes of time but it requires using ice water to immediately cool the eggs down so they do not continue to cook after removing the eggs from the boiling water.

> eggs were placed alternatively in boiling water (Th = 100 °C)

Well nuts, at my altitude water boils at 93ºC. It doesn't appear there is a (known) closed-form solution to this problem, unfortunately :P.


Binary search your way to your values.

Clearly you should turn your kitchen into a gentle pressure vessel. It will make cooking so much easier.

I think you could also just salt the water? That should raise the boiling temperature and hopefully it doesn't seep into the egg, though I think eggs can use some seasoning!


> you could also just salt the water?

Hmm, so to get a 12.5ºF dT with water and NaCl we need about 6.7 mol salt per kg water [1]. That's almost 400 g/kg, more than 10x the salinity of seawater.

Pressure-vessel kitchen it is.

[1] https://en.wikipedia.org/wiki/Boiling-point_elevation#Ebulli... i = 2, Kb = 0.93°F kg/mol

[a] That 6.7 ml/kg is technically a molality, something I only point out because it's a silly-sounding word


My rough calcs estimate you would need about 400mg of salt per ml of water to get a 7°C boiling point increase, but the max solubility of salt in 100°C water is 384mg/ml, so you might just get there with a supersaturated solution.

Can sous-vide machines hold 100°C in oil?


I did it this morning. Not sure if I'll repeat it soon, but result is really good.

Thanks for the summary. Did they factor in any of the recently announced retaliatory tariffs?


"The Budget Lab modeled the economic and fiscal impact of the tariff proposal both with and without retaliation."


I just skimmed the article, I saw they mention retaliation, but what about further escalation? I.e. repetitive tit-for-tat?


I could see it being a great option for getting bulk goods into space. Fuel, water, food, spools of wire or powders for additive manufacturing, structural components, etc. Depends on what is cost effective. The difficult part would be catching the payloads.

It would probably be an even better option on lower gravity lower atmosphere celestial bodies.


When you have low gravity and little atmosphere, I can't imagine many scenarios where a spin launcher would be a better fit than a mass driver. One of the biggest problems with a mass driver on Earth is that you need to do it in a vacuum over a huge area, which isn't a problem with - say - launching from the moon. The spin launch approach makes some sense on Earth, given that you only have to build a (relatively) small vacuum chamber and a very well-timed airlock to let the payload get into the atmosphere.

But the counterweight issues, extreme G forces during spin-up, etc make it kind of a non-starter in my mind for other bodies; I'd love to hear arguments for it vs simple mass drivers off Earth.


IMO Kantrowitz laser propulsion seems more practical for that https://www.niac.usra.edu/files/studies/final_report/897Kare...


Comparable in energy to a B-53 nuclear bomb, minus the radiation.

https://en.wikipedia.org/wiki/B53_nuclear_bomb


So a 14 km blast radius it seems.


Unless it lands in the ocean in which case tidal waves, and if on land, probably an earthquake/shockwave.


A comparable ocean impact would be the 2004 Indian Ocean earthquake, which was about 3x more energetic.


I'd assume quakes transform much more energy into tsunami waves than meteorite hit does.


That is not correct.

Earthquakes' energy doesn't all go to displacing water and hence generating tsunamis. An ocean impact is significantly more efficient at transferring energy into tsunamis.

https://www.sciencedirect.com/science/article/abs/pii/B97804...


Interesting, I would assume surface wave dissipation to counteract that compared to seabed origin.


2004 Indian Earthquake was 9.1-magnitude, so it was about 150 megatons of TNT.


The USGS estimated 1.1×10^17 Newton-Meters of energy, which converts over to ~26Mt TNT.

https://web.archive.org/web/20100404013939/http://neic.usgs....


What I just learned from ChatGPT…

Asteroids mostly contain the same naturally radioactive elements we find in Earth's rocks - mainly potassium, uranium, and thorium in very small amounts. When they hit Earth, they don't typically create radiation hazards. Scientists have checked out famous impact sites like Meteor Crater in Arizona and found normal radiation levels. While impacts can briefly create some radioactive isotopes through the collision process, it's really the impact's explosive force that does the real damage, not radiation.


The Concorde relied on an afterburner to achieve supersonic flight, so it burned a ton of fuel. It also could not go supersonic over land because its sonic booms were too loud. This mean that flights could only go over the ocean, and they were expensive due to fuel costs. Boom's goal is to reduce the sound of their sonic booms 30x and eliminate the need of afterburners.


No. I don't think that's correct. The Concorde used its afterburners during take off and to get through the transonic region, where the drag is very heavy. Once you've gone past that the drag drops. At that point the Concorde can turn off the after burners.

Source: https://www.heritageconcorde.com/concorde-engine-re-heats


That's right, the Concorde had engines capable of supercruise - long distance supersonic flight without afterburners.

https://en.wikipedia.org/wiki/Supercruise#Aircraft_with_supe...


IIRC Concorde could super cruise a Mach 2 which is unmatched. It would also flight supersonic for most of its journey which is also presented unprecedented difficulties.

It was really an unique plane.


This is correct, reheat / afterburner was used from Mach 0.9 something to 1.7, after which they'd were off. So yes, Concorde could supercruise.


Legend says the Tu-144 used afterburners the whole time while supersonic, but, then, it seems five units have engines without afterburners (RD-36-51's replacing the Kuznetsov NK-144 used in most of the fleet).

I wonder what was the noise level in those late models.


WHAT ?!?


"The Concorde relied on an afterburner to achieve supersonic flight..."

"The Concorde used its afterburners ... to get through the transonic region..."

Am I missing something, or is there no difference between these sentences?


[flagged]


Not really, that's like saying "they relied on closing the doors to the aircraft to achieve supersonic flight". Both happened, but aren't related if I'm reading the comments correctly.


"The Concorde used its afterburners during take off and to get through the transonic region,"

https://en.m.wikipedia.org/wiki/Transonic


That's a really dumb response. Yes, it relies on closing the doors to achieve supersonic flight too.

The Boom plane doesn't rely on afterburners at any point in the trajectory to achieve supersonic flight. So yes, you would be reading the comments incorrectly.

Gosh this website is full of ignorant people.


haha, good analogy - but his name has "Troll" right in it.


Boom also requires afterburners, at least for now.

You can watch them kick in on the telemetry (which goes from "100%" to "A/B" for all three engines) at the bottom of the video around the 58:35 mark. https://www.youtube.com/live/-qisIViAHwI?feature=shared&t=35...


Boom is not currently flying their intended engines, the Symphony, which does not exist yet. (1) The XB-1 is flying with J85's just like a T-38 has, and just like a T-38 it can go supersonic with afterburners. If the Symphony is able to meet its design goals, it will not need afterburners for any part of flight. How much they will be able to deliver on that remains the biggest open technical question for Boom. (2)

1: Well, their Plan B intended engines. Their Plan A was that one of the Big 3- RR, PW, GE- would make engines for them, but none were interested in taking the risk that a difficult engine could be designed and built in enough volume to make the investment back.

2: Their biggest legal question is over-land supersonic regulations. Their biggest economics question- and probably the biggest and most important of all of them- is how much will people pay for civil supersonic?


> how much will people pay for civil supersonic?

Do we know how much more it's likely to cost? I could easily see people paying 1.5x - 2x.

Anything beyond 2x I imagine would start to price out the average person and anything beyond 5x would probably price out the vast majority of potential customers.


> could easily see people paying 1.5x - 2x

People pay more than that for domestic first class, which doesn’t even have lay-flat seats. $2,500 or even $5k for a New York <> San Francisco 2-hour flight would absolutely sell.


A number of US carriers offer lay-flat seats for at least some of their coast-to-coast domestic flights. UA has over a half dozen Dreamliners flying back and forth daily, all with Polaris cabins. I know AA and Delta have routes with them, too. I agree, a two-hour flight time would be better!


> number of US carriers offer lay-flat seats for at least some of their coast-to-coast domestic flights

They're limited. And I regularly see them going for $4k+.


Their business model for a long time has theorized that they can deliver an operating cost that would allow airlines to offer tickets at roughly current business class ticket costs, which would be a fraction of Concorde ticket prices expressed in current dollars.

I don't know if those theorized efficiencies will be delivered (a lot depends on that engine) or if airlines will price tickets at that level. But it's the theory so far.


With the amount of billionaires increasing, I'd think more people than Concorde had pay for civil supersonic.


The engine in XB-1 test plane is not the same that’s going in the production plane.


When the production engine exists in physical form, we can absolutely discuss its capabilities. The XB-1 demonstrator is, using afterburner to get to speed, demonstrating other design features intended to keep the noise down.

The original plan was a commercial partner for the engines, but the big three - Rolls-Royce, Pratt & Whitney and General Electric - turned them down. It's one of the biggest remaining question marks in the entire project.


s/When/If/


> The engine in XB-1 test plane is not the same that’s going in the production plane.

There IS no production plane, nor can there be. The last company they wanted to use for engines dropped them as a client years ago (others did earlier): https://english.alarabiya.net/business/aviation-and-transpor...


    > The Concorde relied on an afterburner to achieve supersonic flight, so it burned a ton of fuel.
Wiki says: https://en.wikipedia.org/wiki/Supercruise

    > Supercruise is sustained supersonic flight of a supersonic aircraft without using afterburner.

    > Concorde routinely supercruised most of the way over the Atlantic
Real question: How many in-production/operation engines in world can fly supersonic without afterburners? I think it is only a handful, all insanely expensive and backed with squillions of dollars of gov't/military money. And, the maintenance cycle must be out of this world expensive.


Tom Scott visited the site to try out their treadmill crane system:

https://www.youtube.com/watch?v=pk9v3m7Slv8


I knew a guy that would eat a banana per beer. He would portion the bananas out beforehand, so we could tell he was serious when he showed up to a stag-do with two bunches!


Oh man that’s a lot of bloat! Beer + sugar


Anecdotally, I always had much better sleep and mornings every time I remembered to eat a banana (or two!) before going to bed after a night of heavy drinking...


That is so many bananas


i don't drink anymore but if offered i'd down without hesitation a wells banana bread beer or banana beer. tasty stuff


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