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I've wanted this as my business-hours pager sound for a very long time...


People can generally only output their max power for short durations. The output level they can sustain is generally much lower. I bet you could try to model higher limits for short distances, but what those should be could vary greatly depending on personal fitness.


I think that too favors walking the bike up the incline. Anyone able-bodied should be able to do it, some faster than others, but biking up an SF incline is more hit or miss, especially when considering different bikes.

My reasoning for the bike-hike being faster is that legs are designed for it. Legs are only inefficient on flatter ground because you have no equivalent of high gear (like extendible legs), so all that torque is going to waste.


Uhh, excuse me? Legs are inefficient on flatter ground because they don't have wheels.

Legs have to start, go up, go down, stop.

Wheels go brrrrr.


That's some of it too, but in a way legs aren't all that different from wheels in how they work. Most of it is the gearing. Like there's a gear on every mountain bike that will make your feet go down at the same intervals as walking. That sucks on flat terrain. Legs are also not perfectly designed to push pedals, especially for people who don't bike often.


I believe the "wheels on the bus go round and round" :-)


BRouter models this as inertia, I believe.


DNS cache poisoning?


Dang, they aren't catching the booster this time, but I guess V3 is practically a new vehicle and validating the next Starship launch is probably too critical to risk damage to the launch site for now.


I think it's a few things:

They're already highly confident that if they have sufficient control over the booster trajectory they can execute the chopstick catch, so they don't particularly need to demonstrate that part more. Executing a pseudo-landing at sea lets them validate their booster flight controls perfectly fine without risking the launch tower and associated hardware. They can also do stuff like stretch the trajectory and control mechanisms to their limits to see how much they can handle, and not too big a deal if something goes wrong. Presumably any actual landings will be well within the known safe limits on all parameters.

I bet this first booster also has a lot of minor weird things associated with shaking out the manufacturing process, and they don't entirely mind testing to destruction the first one to get rid of it permanently and use the ones coming from a more proven manufacturing process for important work.


The booster catch is a useful trick but when the focus is just getting SS3 into orbit without incident, you can drop a few of the boosters in the ocean with the intent to fix at a later point.


Oh hey, you're right! Somehow I read "water landing" and interpreted it as landing on one of the barges (ocisly or jrti) any clue why that isn't the case? Is super heavy just too big for the barges maybe?


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.


I agree with everything but nitpick: SpaceX currently has two launch/catch towers in Texas, and they are building a third in Florida.


Only one of them is working right now. Their original tower needs to be overhauled to support Starship V3.


It doesn't have landing legs so it has to be caught by chopsticks. They're skipping the barges; either it lands back at the pad or it doesn't land.


Superheavy is 10x larger than the Falcon. Its thrust would sink the barge.


Yeah. Rocket first stage Approx. unfueled mass:

Super Heavy: 200000 to 280000 kg

Falcon 9 first stage (without Falcon Heavy side boosters): 25600 kg


So 200-280 tons. A standard barge can support 1500-3000 tons of cargo. Even with the added weight of a catch tower and a healthy factor of safety thrust isn't gonna sink the barge. Far more likely the major hurdle would be stability issues with how tall it is.


It's not 280 tons... it's a falling object with kinetic energy so that rocket thrust is going to be very problematic for that boat especially if it' hitting unevenly.

That and there's no way for it to stand without a catch tower.


Hypothetically, what's the effect of that much thrust close to a water surface?

I.e. if they cut a hole in the middle of a barge and it was burning at touchdown "against" the ocean

I imagine water doesn't have the kinetic problems that chunks of concrete do, but also that's a LOT of energy for even water, so maybe there'd be steam issues?


Well the idea would be to put a catch tower on a barge so those aren't actually issues.


In Zulip, if a thread meanders with messages about a tangent, the authors/mods can choose to move those messages to a new thread (and IIRC messages with links between the two threads are created so it's easy to jump back and forth for any missing context)


If you're laying a communications cable, you should just do fiber. It can carry any type of traffic at high data rates, and you can upgrade the speed over time by just replacing the optics at the ends rather than having to replace the whole cable. Fiber plans are only expensive if your service level is expensive, or if you have to pay to get the line run to your building


Yeah, as far as I know the only way to be sure is by putting the parent process into a cgroup. Then to kill all of the child processes you have to freeze the cgroup, enumerate the pids, send sigterm/sigkill to all of them, before unfreezing again.


very slowly, with the radio at maximum power, and no obstructions


Yeah, this is going to decimate your battery life. It's great to have in an emergency, don't get me wrong, but I'd probably leave data off otherwise when out remote.


It uses a different transceiver on the satellite which is broadcasting a ~standard LTE signal, at a miniscule data rate


I looked around last week to see if they are on the market yet, and found that Philips already seems to have helium-free MRIs for sale. I'm not sure if they just sealed it better or switched to REBCO.

edit: nvm, finally found more info. it's just better sealed helium https://www.usa.philips.com/healthcare/resources/landing/the...


My understanding is that most of the experiments for NMR with REBCO at this point are geared towards high field NMR (like 30T) whereas medical NMR field strength is down around 1-3T.

I don’t know what the cost delta is between LTS and HTS magnets, but I imagine the much broader applicability of HTS will bring manufacturing costs way down with economies of scale.

In the interim, people are still trying to figure out effective ways to joint the HTS sections.


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