* Posts by Brangdon

565 posts • joined 15 Sep 2008


Germany is helping the UK develop its COVID-19 contact-tracing app, says ambassador

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Re: In the interim, the British government has been forced to adopt human-powered contact tracing

That was always part of the plan. Some people don't have smart phones. Some of those that do, won't install the app. The app was never more than an adjunct to manual contact tracing. At best it helps with situations where the infected person doesn't know all the people they've been in contact with. For example, if they sat on public transport next to a stranger for 20 minutes without exchanging phone numbers. Neither the app, nor manual tracing, can be expected to give perfect track and trace.

Things that make you go foom: Destruction derby as NASA and SpaceX test rocket components to failure

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The robot dog

The robot dog, Zeus, was seen poking around in the debris after the SpaceX test.

Wired: China's Beidou satnav system, 35th bird in orbit. Tired: America's GPS. Expired: Britain's dreams of its own

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Re: and the ability to broadcast both of those things

That's the bit which would need extra hardware, a lot more power, and a licence from FCC (or whoever). If they had, or were applying for, a licence to broadcast GPS signals, we'd surely know about it.

If it happens at all, it'll surely be after Starship comes into operation. They may take advantage of its larger lift capacity to make the satellites bigger and have more capabilities. Or they may just make a separate satellite type. GPS doesn't care about round-trip latency, so doesn't need to be a low orbit.

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Re:ground receivers are too large

The current Starlink receivers are for receiving and sending internet. A positioning system aerial would have a different purpose and size. It wouldn't need to transmit at all, so it wouldn't need to aim a beam. There's no reason for it to be bigger than a normal GPS aerial.

Winter is coming, and with it the UK's COVID-19 contact-tracing app – though health minister says it's not a priority

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Re: Well that aged well

Gov claims to already have both apps. Their version doesn't work well with iPhones, and the Google/Apple app doesn't do a good job of estimating distance. They hope to persuade Google and Apple to adopt their distance-estimating code. Part of the delay may be waiting for that to happen.

Good distance detection is important to avoid false positives. People will have to self-isolate for 2 weeks based on this app, so any positive is disruptive. Gov says they won't release it until the false positive rate is low enough. (Part of the goal of the centralised app was to collect enough information to help trackers reduce false positives.)

This was from the daily briefing.

The girl with the dragnet tattoo: How a TV news clip, Insta snaps, a glimpse of a tat and a T-shirt sold on Etsy led FBI to alleged cop car arsonist

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Re: Gloves and goggles; whoda thought it?

Tear-gassing peaceful protesters is not a good thing during the pandemic. It messes up their respirator system.

GitHub to replace master with main across its services

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Linus once remarked that he names his products after himself.

Russia drags NASA: Enjoy your expensive SpaceX capsule, our Soyuz is the cheap Kalashnikov of rockets

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US cheaper?

NASA Administrator Jim Bridenstine said partnering with a private company like SpaceX was necessary as it had become too expensive to purchase a journey to the floating space lab using Roscosmos’ Soyuz rockets. SpaceX, on paper at least, works out millions of dollars cheaper than using Soyuz.

However, Boeing's Starliner is more expensive than Russia, at $90M per seat, and NASA don't seem to mind paying that. So this is not really about cost.

SpaceX is about to launch its first Starlink internet satellite sporting a sun visor following complaints by astronomers

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Re: Have I got this right?

Read the update about it on their website if you want more information. https://www.spacex.com/updates/starlink-update-04-28-2020/

SpaceX Crew Dragon docks at International Space Station

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Re: Return

Crew Dragon is surprisingly different to Cargo Dragon. For example, it has a lot of launch abort stuff that they don't bother with for cargo.

Laughing UK health secretary launches COVID-19 Test and Trace programme with glitchy website and no phone app

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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.

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Re: most likely route of infection

According to the CDC, fomites are not the main way the virus spreads. It can happen, but it's rare compared with face to face transmission. Reducing R0 is about addressing the most common vectors.

Beardy Branson’s 747-assisted sat-launcher can’t get it up

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Re: get your kit into space with less waiting and from more parts of the world

Including from Cornwall.

And it should be noted that Virgin Orbit is a separate company to Virgin Galactic, with more useful goals and a more plausible way of achieving them.

NASA launches guide to Lunar etiquette now that private operators will share the Moon with governments

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Re: nobody should claim property

The Outer Space Treaty says you can own the resources you extract. You just can't claim an entire planet, moon or asteroid by landing on it and planting a flag.

Academics demand answers from NHS over potential data timebomb ticking inside new UK contact-tracing app

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Re: Smartphones

It needs low power Bluetooth, so very old phones won't support it.

UK snubs Apple-Google coronavirus app API, insists on British control of data, promises to protect privacy

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Re: timestamps

The Google/Apple scheme changes the token every 15 minutes. This means the app knows to within 15 minutes when an encounter with an exposed person happens. I expect the NHS scheme is the same. If not, and it only changes the token once a day, that makes tracking easier.

How's your night sky looking? The Reg chats to astroboffin Mark McCaughrean about Starlink and leaving a mark

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Re: It's full of stars...

You need to be the right side of them - north or south I forget which - else they don't reflect enough sunlight to you for you to see them.

SpaceX's Elon Musk high on success after counting '420' Starlinks in orbit and Frosty the Starship survives cryo test

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Re: This may be a really obvious question.

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.

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Re: When will Starlink become operational?

Private beta in 3 months, public beta in 6, for higher latitudes in North America.

Academics: We hate to ask, but could governments kindly refrain from building giant data-slurping, contact-tracing coronavirus monsters?

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Re: Yeah, Right!

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.

NASA makes May 27 its US independence day from Russian rockets: America's back in the astronaut business after nearly nine years

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Re: Musk is more interested in space...

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.

Europe publishes draft rules for coronavirus contact-tracing app development, on a relaxed schedule

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Re: The Oxford paper doesn't say 60% is really enough

It has a beneficial effect even if it isn't perfect. Anything that helps get R0 down is good.

So how do the coronavirus smartphone tracking apps actually work and should you download one to help?

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"their phone will release the identifiers of all the other devices"

"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.

SpaceX beats an engine failure to loft another 60 Starlink satellites

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Re: A note on profit.

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.)

US prez Donald Trump declares America closed to those flying in from Schengen zone over coronavirus woes

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Re: Hmm

Yes, it was a good thing the UK was outside of the Schengen Zone even while gaining the benefits of belonging to the EU.

After 1.5 million days of computer time, SETI@home heads home to probe potential signs of alien civilizations

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Re: Sorry, too late...

You are assuming they aren't local. If they are within, say, 50 light years of us, communication would be feasible. Obviously transmitting continuously without waiting for answers or acknowledgement.

Starship bloopers: Watch Elon Musk's Mars ferry prototype explode on the pad during liquid nitrogen test

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Re: Wasn't planned

It wasn't planned, but it can't have been too unexpected either. They were using a new welding scheme and had already noticed they'd set it up wrong. Fault corrected for SN 2. This SN 1 was going to be pressure-tested but they were never going to attach Raptor engines to it.

Your phone wakes up. Its assistant starts reading out your text messages. To everyone around. You panic. How? Ultrasonic waves

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Re: Is poo particularly flammable?

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.

How many times do we have to tell you? A Tesla isn't a self-driving car, say investigators after Apple man's fatal crash

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Re: dowsing them with water is ineffective

No, it isn't. Dowsing with copious water is the recommended approach because it cools the batteries to below the point where they can burn.

Flat Earther and wannabe astronaut killed in homemade rocket

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A pure-random-evolution model doesn't make a lot of sense

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.

Smartwatch owners love their calorie-counting gadgets, but they are verrry expensive

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Re: No batteries needed

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.

Microsoft to bravely defend US democracy for a slack handful of voters in Fulton, Wisconsin

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Re: Paper ballots and markers

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.

SpaceX's next Starlink volley remains stuck on Earth to glee of astronomers everywhere

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Re: SpaceX launches

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.

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Re: Starlink launched

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.

Bloke forks out £12m, hands over keys to tropical island to shoo away claims that his web marketing biz was a scam

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Re: The pillage of the scammed

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.

Voyager 2 gets back to sciencing while 'unstoppable' Iran promises world more 'Great Iranian Satellites'

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does not plan a constellation of multiple thousands

"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.

Starliner snafu could've been worse: Software errors plague Boeing's Calamity Capsule

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"Process escapes" is the new "Normalising the deviance"

"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."

Astroboffins may have raged at Elon's emissions staining the sky, but all those satellites will be more boon than bother

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Re: fiber

The markets for this include marine and aviation. Good luck running fibre to an aeroplane.

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Re: Chinese Great Firewall

Musk has said he will comply with local censorship laws. He won't be breaching the Chinese Great Firewall.

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Re: "democratise the cosmos"

Are you saying that OneWeb and Amazon won't offer mass-market internet? My understand is they will. OneWeb will use local resellers everywhere; Starlink will where necessary.

Wake me up before you go Go: Devs say they'll learn Google-backed lang next. Plus: Perl pays best, Java still in demand

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Re: Some thoughts about "slow languages"

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.

Over the Moon? Not quite: NASA boss has a good whinge about 'counterproductive' Authorization Bill

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Re: Testing... is this think on?

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.

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Re: Three steps forward and two steps back.

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.

Remember that 2024 Moon thing? How about Mars in 2033? Authorization bill moots 2028 for more lunar footprints

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Re: Are all the movies 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.

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Re: centrifuge

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.

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Re: Even billionaires can't keep paying for stuff like this

Some estimates have SpaceX Starlink constellation bringing in $30B a year. That is a lot more than NASA's budget. Of course there will be costs, and eventually competition, but there should be plenty left over for Mars.

Two billion years ago, snowball Earth was defrosted in huge asteroid crash – and it's been downhill ever since

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Re: Mars rate of atmosphere loss

Mars rate of atmosphere loss turns out to fast in astronomical terms but slow in human terms. If we have the ability to give it a decent atmosphere, we should also have the ability to top it up every 100,000 years or so.

LastPass stores passwords so securely, not even its users can access them

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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.



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