Re: Oh No Surely Not...
The phone call will tell you to go on the website and enter a case number. It's only if you don't have internet that you need to trust the caller.
555 posts • joined 15 Sep 2008
It's aimed at people in rural areas who don't already have cable or equivalent. It can't serve many people within a given area, so won't be for people in cities. Price is expected to be around $80/month. Even if it is higher, it's not expected to be ludicrously expensive.
On controlling people: you apparently don't understand how the Apple/Google proposal works to protect privacy.
On whether tracing can slow COVID-19's spread: yes it can. Although the tracing starts with someone who is already symptomatic and infectious, it then tracks down people who have been exposed and warns them before they become symptomatic, and hopefully before they become infectious. At any rate, the earlier they are warned the earlier they can stop infecting other people. It doesn't have to be perfect. Anything that reduces R0 helps.
On the cost of manual tracing: the whole point of the app is to provide some tracing automatically, without needing a lot of resources for manual tracing.
If you are rich and you want to get richer, two of the worst things you can invest in are making cars, and making rockets. Both very hard fields to succeed in, and even harder to make significant money.
Musk's extra wealth is directed into SpaceX, which is a company that is pro-space. He wants to start a colony on Mars. That's a hugely expensive endevour that will need every bit of it.
"If someone is then diagnosed as having COVID-19 they can self-declare that fact and their phone will release the identifiers of all the other devices that they were close to over the past 14 days."
That's not how it works. Instead, the phone uploads its own identifiers, that is, 14 of them, one for each day. These are added to a database. Every day, each phone downloads the database, turns each daily ID into a set of 15-minute IDs, and then compares that with the list of IDs that that phone has been in contact with. The upshot is that your list of contacts never leaves your phone.
They're probably still spending 10% of the cost of a booster on refurbishing. Let's say they save $15m per reuse. That's 66 flights to cover the $1B. So far they've reflown about 34 boosters so about half way there. Even allowing for Starlink launches there's a chance they may never break even, if Starship becomes available early next year. (Of course, Starship likely couldn't happen without the experience with reuse they got from Falcon 9.)
In "flaming bag of poo" it is the bag that is flaming, not the poo. The poo is concealed within the bag. The idea is that the victim doesn't know it is there, stamps on the bag to put the fire out, and thus gets poo on their shoe and possibly splatters themselves.
If it helps, the conventional model is not purely random. The full title is "evolution by natural selection", and natural selection is not random. It has a bias towards survival of the fittest, which is consistent over time because the environment changes slowly.
I have some automatic watches. One drawback is that you are supposed to get them serviced every 5 years or so, and doing that generally costs more than buying a new watch would.
I am currently using an oldish Casio Pathfinder that is solar powered, so should last decades before the battery wears out. It is also updated by a radio time signal, so always has the correct time. Those two features make it superb as a basic watch in my view. It shows date, phase of moon, air pressure graph, and has the usual lot of features (compass etc) most of which I have used. I switched back to it from a Garmin because it has a stop-watch that shows 100/th seconds, which I sometimes use as a random number generator. Smart watches tend not to update their display so often. It looks ugly and nerdy and has too much text written on it, but I do like its features.
From what I, a non-American, have gathered, Americans have found that paper ballots don't scale well to the large number of elected officials they have. In the UK we are typically only voting for one candidate. So we can first separate the papers into a pile for each candidate and then count how many papers in each pile. Both processes able to be done in parallel, so as long as you have counting clerks in proportion to the number of voters, it take constant time.
In the US they vote for scores of positions at the same time. They put all those votes on the same piece of paper. That makes counting the votes hard. They can't make piles of votes without first tearing the voting paper into strips - one strip per position being voted for. They find that impractical. So counting the votes by hand can take months.
The apparent "collapse in demand" is partly a result of their success. The previous high cadence had been possible because they had a backlog of payloads that were delayed by the investigation into the AMOS 6 oopsie. By last year they had cleared that backlog and so now they are waiting for customers instead of customers waiting for them. Also, the satellite business is cyclic, with GEO satellites generally lasting 15 years, and is now in a bit of a lull. And they've finished launching the Iridium constellation. It looks like the industry is waiting to see how the new trend of LEO satellites pans out before committing to more GEO ones. The high cadence basically shows that reusing boosters saves time as well as money.
The IPO won't happen for several years. It has nothing to do with their Starlink cadence. They are obliged to get their satellites up ASAP, else they could lose their frequency allocations. Also they do want it to start making money, which will happen (or not) whether or not there is an IPO. It's expected to be operational this summer, although service may be limited at first.
The plan had been for the Dragon astronauts to stay on ISS for only a week before returning. Now NASA is considering having them stay for months, so they can get some actual work done while they are up there and to avoid the US contingent being reduced to a single person. If the extended stay happens, the astronauts will need to be trained on the activities they will be doing. That will delay the Dragon 2 launch by several months.
This is about cognitive dissonance and confirmation bias. Once you have invested time and/or money into the thing, you want it to be true, and will tend to dismiss any evidence to the contrary. It's part of most confidence tricks. The first step is to engage in dialogue, and the longer the conversation continues the more invested the victim is.
"at least Brit-based OneWeb does not plan a constellation of multiple thousands of spacecraft"-- and then "grow to 1,980 satellites in later phases", which sounds like multiple thousands to me. No doubt if they are successful they will add more. They are higher, so harder to see for the naked human eye, but I believe that doesn't make much difference to telescopes. They will also not naturally de-orbit in reasonable time if they malfunction.
That said, I am becoming a bit of a fan of OneWeb. They are like Blue Origin in that the cool stuff they do tends to be eclipsed by the even cooler stuff SpaceX does. Unlike Blue Origin, they have working hardware in orbit. They can provide service over the oceans and poles without inter-satellite links, so they may get to the marine and airline markets first.
"But the two software issues you talk to that you all know about are indicators of the software problems, but they are likely only symptoms, they are not the real problem. The real problem is that we had numerous process escapes in the design development test cycle for software."
It's not just about performance. Turning 20 times as much battery power into heat is also an issue. If you are running in the cloud on a rented computer, you may be paying 20 times as much for that, too.
You may also find your program is expected to process twenty times as much data after 10 years, too.
Conditions on Mars are so different to the Moon that you don't learn much about living on one from living on the other. Such things as can be tested could be done more easily in Earth orbit without going to Mars. The Moon is an interesting destination in its own right, but as a step to Mars it is a distraction.
SpaceX will go to Mars using their Starlink revenue, which will likely be more than the entire NASA budget. They got badly bitten on Dragon 2 by NASA continually changing its mind about the details. For example, changing from 7 seats to 4, or giving bad models for the parachutes so they had to be reworked. That's what caused the delays - that and not being given the promised money early on.
NASA was against fuelling the rocket with the astronauts on board mainly because it hadn't been done that way before. It's arguably safer than having ground crew working around a fully fuelled rocket - that would never be allowed for uncrewed missions, so why allow it for crewed ones? By the time the rocket is fuelled, the ground crew should be cleared well away and the astronauts safely ensconced in the capsule that has a launch abort mechanism to protect them if anything goes wrong.
We don't yet have the capability to construct much in Earth orbit. Musk is still learning how to build Starship on land, and he'll need it to get to orbit. Once Starship is operational, we can consider using it to build orbital platforms that may eventually be capable of heavy industry.
The way to slow down heavy things on Mars is to use the atmosphere. That means going to Mars orbit is harder, because you have to dip in an out of it. It's easier to go direct to the surface. Also, Mars orbit is a hostile environment - worse than low Earth orbit because Mars doesn't have a magnetic field to deflect radiation. Worse than Mars surface because Mars atmosphere gives at least some protection, and the body of Mars itself cuts off half. The surface also avoids the problems of microgravity.
Orbit to orbit may happen one day, but probably not for 30+ years.
There's not much point spinning the astronauts just when they are lying down asleep. To benefit they need to be moving around, ideally exercising.
SpaceX plan seems to be to make the journey fast. 4 months in microgravity, then straight down to the surface. Hanging around in orbit is harder than landing, and you are still exposed to microgravity and radiation, so you want to get down ASAP. The notion of an orbit-only mission makes no sense.
Would it survive if you house was hit by lightening and burned to the ground? You should at least have off-site backups. The only reason not to do this is if you don't trust the encryption you used with the backup.
And once it is backed up offline, you might as well make the backup available across multiple devices so you have passwords everywhere.
Remember that this flight isn't expected to happen until 2023 at the earliest, so she will have had 3 years to get to know him. If she still doesn't trust him, she shouldn't go. Also, it won't just be him and her. There will be a dozen of so artists along too. And the Starship isn't some cramped capsule.
Really this is just a dating show with 1 eligible bachelor and several prospective women. It's a common format. The Dear Moon flight is a hook.
Typically the engines shut down shortly after the kaboom, if not shortly before. Where "shortly" is quick enough not to matter.
It worth remembering that the LOX and fuel tanks are kept separate, so the kaboom is more of a slow fire than a well-mixed gas explosion, and much slower than a detonation. It's also worth remembering that SpaceX will have simulated various situations and will be testing what they consider to be the toughest case - and that Boeing consider simulation alone to be adequate.
No, I don't agree, for the reasons I gave in the post you quote. The galaxy is less then 14 billion years old, and I already told you how many stars it contains. Life took a few billion years to evolve here. It's quite plausible that it was unusually fast for us. If it normally takes 10 times as long, the galaxy (and the universe) wouldn't be old enough for it to have happened.
The thing is, although the galaxy age and size are big, the chances of life may easily be correspondingly low. With a sample size of 1, and that sample biased, we can't be sure.
First in this galaxy is plausible. First in the universe is less likely.
Our galaxy has around 300 billion stars. If you look at how many steps were involved in getting to intelligent life on Earth, it's easy to believe it's so astronomically unlikely that it is a rare event even with that many stars. (Eg going from simple single-cell creatures to complex single-cell creatures, or going from single cells to multiple cells.) We also don't know how important and rare our Moon is, or whether it is necessary to have at least two planets in the habitable zone. Nor do we know how long intelligent life survives for when it does evolve. The odds of us remaining a high tech civilisation (eg, able to use radio telescopes) for the next 500 years don't seem that great. When people take the Drake equation and set all the unknowns to 1%, they are being unimaginative.
However, the number of galaxies in the universe seems unbounded, so there is probably intelligent life in other galaxies. Too far away to visit or communicate with.
Musk's timeline doesn't involve landing from orbit until a bit later. Starship can't make orbit and land again on its own even with no payload. It needs the Superheavy booster, which SpaceX haven't started constructing yet. There's a chance it will happen by end of this year if all goes well, but even Musk doesn't think it will be in the first half of the year.
I thought LOX only affected the launch window if it is sub-cooled. If it is only cooled to its boiling point, when it gets warmer it just boils off, and the loss can be replenished just by topping up with more LOX. If it is cooled below that point, when it warms it merely expands a bit and so it can't be topped off.
Sub-cooled LOX is used by SpaceX because it is denser and so gets a bit more performance out of the rocket. Most other launch providers don't bother.
It's more likely it read the wrong clock field. Apparently the 11 hours roughly matches the difference between when the computer was switched on and when the rocket launched, so it may have taken the time elapsed from boot instead of time elapsed from launch. With two such similar elapsed-time fields it would be an easy mistake to make, and hard to spot during code review.
(Which doesn't excuse not finding it during testing.)
The key phrase here is "normalisation of deviance". That's what reports blamed the Space Shuttle disasters on, and that's what's happening here if Boeing is allowed to continue despite their several failures. It means unexpected things are going wrong but they're ignoring it because no-one died.
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