In 2001 I was operating mirrors of several sites and had the mirror scripts set to not delete things if the master "went away", following incidents in 1994

More importantly the ftp sites themselves were supposed to be publicly accessable mirrors of archives of software collections - the point being that there were master copies "somewhere".

In 1997-1999 there had already been a number of instances of script kiddies wiping out ISP webservers (and their disk-based "backups"), which underscored the importance of keeping a master copy of your work somewhere offline and out of reach of accident or malice.

There was an alarm. The crew didn't react to it, most likely due to operational overload - the same overload which probably led to the open valve in the first place.

In other hypoxia incidents people have reacted to human voices whilst still being unaware of alarms.

More to the point, with external monitoring the gradual loss of pressure (or the fact that the valve had been left open in the first place) might well have been noticed and flagged long before the alarm went off.

Having systems being able to be monitored from _outside_ the capsule means that you can assign more resources under lower individual stress to making sure your crew is kept alive.

Somewhere between "non-existant" and a few metres per second at most.

Sound transmission requires that movement can be transferred between molecules (Just like a newton's cradle)

At the altitudes concerned, gas molecules are so widely dispersed that collisions are occasional to rare, despite giving enough friction to generate a plasma.

"It's difficult to keep a tube depressurized when it's that large"

Pumps capable of handling that already exist, as does the materials science to make tubes capable of handling the crush pressure (which incidentally also makes them pretty much immune to onboard bombs - the overpressure pulse isn't enough to overcome the pressure differential.)

The most important aspect of the project is financial. Tunnel boring and building viaducts doesn't come cheap and the USA political system is so corrupt that a project can easily treble in costs just paying off officials to keep them onside.

It was costed in the 1960s-70s as running into the trillions, but such designs were full vacuum linear motor systems

Hyperloop makes a number of pragmatic/practical changes (such as allowing enough air in to provide air bearings, which in turn reduces engineering costs of suspending the capsules dramatically). Whether it's fully economic to do so is another matter.

My personal belief is that it will prove uneconomic for passengers unless longhaul freight is also carried and that in turn requires large tube diameter to handle intermodal containers.

In all liklihood it would be easier to build a hyperloop in Europe than in the USA, for the same reasons that HSR is all over the place here and non-existant in the USA. Ditto Japan or China - I think the current japanese maglev design is likely to prove uneconomic long-term due to friction issues and the sheer cost of maintaining an uncovered track. (birdstrike?)

Unlike rail, the hyperloop vehicles are able to bank inside the tubes so that cabin gravity is always apparently floorwards. (In fact if the CoG is low, then the banking comes for free, assuming a cylindrical profile.)

That in turn allows much tighter bend radii than rail where the limitations are mechanical stresses on the tube from passing pods and how much vertical G forces you're prepared to subject your passengers to (3G for 30 seconds is quite tolerable from my own experience deliberately spiral diving aircraft. More than that and passengers will probably complain loudly)

It's worth pointing out that HSR systems in the EU use bend radii in the region of 4-5 MILES for full-speed direction changes, and as with rail, the right-of-way only needs to be 30 feet wide for hyperloop.

What if the replacement viaduct took the i5 over the grapvine grade as well as the hyperloop?

There are a lot of roads where a viaduct over a valley would save considerable time, money and fuel over the current norm of terrain-following. Just because that's the way stagecoaches did it doesn't mean that it's appropriate for newer technologies.

At hypersonic velocities a trailing antenna is going to flail around so much that it'll probably snap.

I wouldn't be at all surprised to find that NASA tried something like this back in mercury days, as I've spoken with some of the scientists who worked on the unmanned and chimp craft. Many are now long-dead, but they had a lot to tell which isn't in any history file (such as desperately giving CPR to a chimp...)

Whenever you see "xyz is going at N times the speed of sound" - it's the speed of sound at sea level (standard temperature and pressure), not the speed of sound in the local environment.

Media always dumb this down. "Journalists" are not reknowned for their comprehension skills for the most part.

(Whenever you see media massively screwing up reporting of stuff you know lots about, bear in mind that every expert in every field has the same gripe about them)

"How much can a ship take corrections at that stage? "

Quite a bit. The basic reentry designs currently in use have substantial lifting body abilities, etc. and there's the possibility of picking up stuff the crew may have missed due to operational overload

(eg: the soyuz crew who asphixiated during reentry due to a faulty valve. With warning, they could have closed their pressure visors and used suit supplies for a few minutes, but the pressure loss was so gradual that they didn't notice it and simply drifted off)

China has a very long history of technological innovations exported to the rest of the world. It's only since the start of the industrial revolution that it's fallen behind and even then only slightly.

The biggest stumbling block in the last few decades has been communism discouraging "tall poppies" - now that the brakes are off it's only to be expected that innovations would start pouring out.

(The world would benefit greatly from china being treated as an equal in space. Locking the chinese govt out of ISS is counterproductive, as will be locking the indian and brazilian govts out when their manned space programs are underway. We only have one planet and nationalist "competition" is bad for the ecosphere.)

"The DOOM archive was saved"

If you rely on a 3rd party to maintain the _only_ copy of your work then you're a fucking retard who probably deserves to lose your shit

(and please tell me your projects so I know to avoid them. They're clearly not going to get long-term support)

Seriously. it's a total facepalm if XYZ site (or website) goes away and the data that was on it isn't mirrored somewhere else (or isn't simply a mirror of your private, backed-up master server)

There is already malware circulating which hijacks android phones in order to spam out text and voice messages - it's believed this is precisely because of increasing whitelisting practices.

Politicians, churches and charities have gone and shat in their own nest on this one. (As they did with loudspeaker trucks)

The FCC has been looking at restricting political robodialling for a while due to the sheer number of complaints and it's highly unliklely that only the one exemption will be pulled.

It's not a restriction on speech, it's a restriction on the manner of speech (as are loudspeaker truck laws) and forcing speech on those who do not wish to listen to it.

> the old movie trope of "keep them on the line while we trace this call" is bogus

Back in the days of strowger switches it had to be done this way but that was a very long time ago.