* Posts by AdamT

503 posts • joined 7 Sep 2010


tz database community up in arms over proposals to merge certain time zones


Actually ....

... why don't we do away with timezones altogether? We all (*) have a device that knows _exactly_ where we are so could easily calculate a precise local time for you. Then all we have to do is indicate exactly where the event is due to occur at its local time and then everyone knows exactly when too!

So bus/train timetables would factor in the position of the stop/station and google maps route finding would know where you are starting from (and what time it is there) and compare that with the place you are going (and work out what time it is there), etc., etc. ...

There might be a few minor teething problems but I'm sure we could make this work!

It would have a couple of advantages of spreading traffic and power requirements out a bit as depending on which side of the country you are, you would be doing things at a slightly different UTC time compared to the other side.

This is a great idea! What could possibly go wrong?

(*) well, many of us and a rapidly increasing proportion of the human race.

NASA halts Mars comms for two weeks as Sun gets in way of Red Planet


Re: Comms relays?

I think that is really hard to do. Getting into solar (rather than earth) orbit takes a lot of energy even with the fact that we are already moving at 100,000 km/h in the right direction. If you want to go at that speed but "up" compared to our orbit that would take a huge amount of energy. Alternatively you might be able to do a "gravity sling" around Jupiter or Saturn - I think one of the pioneer or voyager probes managed a bit of a lift above the solar system plane this way. Whether you could really get a complete "vertical" that way, I do not know ....


Comms relays?

Presumably, at some point (i.e. if there is a permanent/semi-permanent human presence on Mars) we will need communication relays to avoid this?

I guess they could go at the Lagrange 4+5 (trojan) points of either Mars orbit or Earth orbit. Or both?

I wonder if anyone is planning this yet?

BOFH: You'll find there's a company asset tag right here, underneath the monstrously heavy arcade machine


Re: Personal heaters

Before I started my PhD I had to attend the "electrical safety lecture". The lecturer had some kit where he could relatively safely demonstrate this sort of thing. i.e. all protected with big isolation switches and circuit breakers, RCDs, etc. However, the lecture was cut short when his demo of "coiled up extension lead under carpet tile happily drawing 20A without blowing the fuse in the plug" did eventually blow the fuse (when the cable melted) .... of the entire lecture theatre. So he had to turn it into a lesson on how rubbish fuses are. The plug fuse hadn't blown, his kit fuse/circuit breaker hadn't blown (around 50A or so, if I recall) but the lecture theatre fuse had blown at around 200A or so.

The video on "why you shouldn't put volatile chemicals in a fridge" was quite good though.

And his description of the "don't be the idiot who fitted an extension block but forgot to wire it up so made a double plug ended cable to energise the extension block" incident was pretty horrific.

Basically, when it comes to electricity, most people (including a lot of people who should know better) are pretty dumb. When RCDs were becoming a thing, I recall a PSA (or advert) where the point was made that if someone mows through their hose they would go and turn the water off before picking the hose up. But if someone mows through the cable for the mower they are much more likely just to pick the cable up straight away...

Crank up the volume on that Pixies album: Time to exercise your Raspberry Pi with an... alternative browser


Re: Pixies

Sorry, I should have said that I am familiar with the Pixies and have several of their albums (actual CDs!). I just couldn't work out if the title was a reference to a specific track or lyrics...


Re: Pixies

OK, I just can't work it out. Can someone explain the Pixies reference in the headline?

Electron-to-joule conversion formulae? Cute. Welcome to the school of hard knocks


Re: Ask the dog - it has an 80% success rate

Ah, yes. I used to refer to that as "Teddy Bear debugging" ...

... until the fateful day when I turned to my colleague, explained the problem, worked out the issue and then, while he continued to remain silent and with no further context, I announced "You are my Teddy Bear".

I briefly considered exiting via the window.

I think "you are my rubber duck" would have been better, but still weird

Catch of the day... for Google, anyway: Transatlantic Cornwall cable hauled ashore


Re: How long is it?

Well the cable is broken up into sections of around 50 to 100km length because you need a repeater to boost the signal. So the cable only has to be made in lengths up to that spacing and then the repeaters will be connected in at the appropriate intervals. They do try and do all this on dry land and I think in all but the longest cables the whole lot can be loaded into _huge_ cylindrical tanks which are then loaded on to the ship. There is a lot of very clever handling equipment to deploy the cable from the tank and then, every 100km, the repeater (which will be in a rack outside the tank) without twisting or kinking the cable.

A transatlantic cable will be several thousand kilometres and I think that can usually be done in one or maybe two goes. The cable length is slightly longer than the actual path as it is laid in a slight S pattern so that there is some slack if it ever needs to be hauled up for repair.

Ships can do cable jointing and repeater attachment/replacement while at sea, but it is to be avoided if possible! If you thought domestic cable stripping was annoying then here you have to start with an angle grinder and then work your way down the set of tools until you get to the delicate, needs to be kept very clean, fibre splicer. Then work back up sealing everything in and bonding the steel core cables (which carry the tension) and any armouring layers into the "joint" or the repeater end connector. A strange mix of hi-tech and maritime-chunky ...


Yup - I worked on TAT-9 back in the '90s.

There are a couple of bits of copper in the middle of the cable (with the fibres inside) - one is just wrapped round as a C and the other is wrapped and then welded (brazed?) into an O. The high-tensile steel cables which wrap that don't contribute that much to the conductivity.

The regenerators (one per fibre) were powered from the drop across a zener diode so each repeater dropped about 60 - 80V.

The current was 1.6A and this was achieved by applying about +9kV at one end of the cable (with respect to the big earth rod) and about -9kV to the other end (with respect to its big earth rod).

Obviously most of the power is lost in the cable.

The cable forms a crude coaxial cable (with respect to either its armouring or to the sea water as ground) which means you get some "interesting" effects if the cable either breaks or shorts. e.g. 100s of amps of current spike so the zeners were rated to about 500A and the expectation was that the repeaters would survive, a cable ship could repair the break and the cable would be back online.

After failing to make it to orbit, Firefly Aerospace asserts it has 'arrived'


Re: Keep going

I think he said the same about the Falcon Heavy test flight. Something like "as long as it clears the tower so the explosion minimises the damage to the ground equipment then I'm happy"


Re: Keep going


You may get mocked by people who don't understand (especially if you start listing achievements on a mission that actually ended in a fireball) but those who do understand will appreciate that _all_ the things have to go right. Getting 9 out of 10 right may still end in a fireball but is still an improvement over last time when you only got 7 out of 10 right even if to the observer they both appeared to end in a similar fireball.

To be honest, when this is the first flight, not exploding on and destroying the launch pad should be considered a bit of a win.

In fact, for this and the other recent launch (that failed) from Alaska I think there was some suggestion that they deliberately prolonged the flight as long as they could in order to clear the range and get the debris into the sea. So the fact that they still had control over an ailing rocket (in both cases) is really quite impressive.

Boston Dynamics spends months training its Atlas robots to perform one minute of parkour almost perfectly


wait until you see them (SpaceX) attempt - and hopefully succeed - in catching an even bigger booster out of the air using a couple of robotic arms attached to a huge tower...

US watchdog opens probe into Tesla's Autopilot driver assist system after spate of crashes


Re: A solution looking for a problem

I believe a similar judgement had to be made for airbags. There are a few rare types of impact where the airbag will likely kill you or do more serious injury (compared to not having one) but in the vast majority of situations where it deploys, it will save your life or reduce the severity of your injuries.

Engineers work to open Boeing Starliner's valves as schedule pressures mount


Re: The SRBs have a time limit

This configuration of Altas 5 does have two SRBs on it:


(I think Altas 5 can have between 0 and 5 SRBs depending on mission profile)

But I don't know whether there are any "use by" limitations on those ones ...

Edit: Ah yes, here is the upsettingly-asymmetric set of options for the SRBs: https://spaceflightnow.com/atlas/av001/020814rocket/a5solids.jpg

BOFH: You say goodbye and I say halon


Re: I'm curious

If I recall correctly, from when we looked at this as a case study in my engineering degree, they did the computer modelling, they didn't believe it, so they built a 1/3 scale model in a quarry and tried it for real.


Well the author is New Zealand based (and always has been) according to wikipedia and the El Reg bio:



But I think it is generally accepted that the character and stories are based in the UK, and the UK specific references seem to be consistent with that (as KLane and The Oncoming Scorn mention): pubs, UK cities, UK slang and pounds, etc.

Either that or NZ is much more similar to the UK than I was aware...


Re: I'm curious

Yeah - there was a film about that. I'm sure it was hyper-well researched and highly accurate!

Backdraft (1991): https://www.imdb.com/title/tt0101393/

But it is a real effect and something similar happened in the real-life, horrifying and closer to (my) home disaster at Kings Cross London Underground station in 1987. The fire created it's own oxygen deprived environment which enabled it to slowly pre-heat the old wooden escalator steps until the flashover/backdraft event could suddenly occur. The combination of these two effects was previously unknown and now has a name: https://en.wikipedia.org/wiki/Trench_effect

(sorry - don't mean to be all real life and depressing on a humorous article! But this stuff is complicated and fascinating I find...)


Re: I'm curious

I wonder if there is a risk of ending up with the opposite problem?

i.e. something flammable gets hot enough to burn if there was a normal oxygen level but doesn't burn because there isn't enough oxygen. Then someone opens a door or there is a leak of regular air into the room and suddenly that thing bursts into flame with no other warning.

I guess the key point is that hot/burning things are Bad and all you can really do is try to influence what type of Bad you get.

England's controversial extraction of personal medical histories from GP systems is delayed for a second time


I think one of the issues is that "standard" anonymisation isn't good enough for health records particularly if you have a rare condition or combination of conditions. The fear then would be that the supposedly anonymous NHS Digital data could then be easily matched against other sources of data.

Funny how Sir Tim Berners-Lee, famous for hyperlinks, is into NFTs, glorified hyperlinks


Actually ....

... the quote from Sotherby's (used in the subheadline) about the similarity with autographing a book is the first time that NFTs have made even the slightest bit of sense to me.

Obviously they have many other problems (such as wasting energy) but the analogy partially works (for me at least): "I know you also have an identical copy of the book but mine is special (a.k.a. more valuable) because someone signed their name on it"

This does suggest that the "value" is likewise going to be highly subjective in the same way as you might not care about this author signing a book but you might care about that one doing it.

I wonder if the analogy will extend to, what I understand is quite a big problem in the "autographed goods" market, of fakes?

Excuse me, what just happened? Resilience is tough when your failure is due to a 'sequence of events that was almost impossible to foresee'


Re: Black swan event

They are rare but a few examples in the UK:


( https://goo.gl/maps/3YinKfXzMmdyZRg16 )

Dawlish (on south west coast)

( https://goo.gl/maps/XRJyKZN2kz8ETg259 )

I think both sets are "natural but monitored" i.e. they are not captive or bred, and arrived under their own steam but they are looked after and encouraged in their current locations.

We don't know why it's there, we don't know what it does – all we know is that the button makes everything OK again


Actually ....

... I was on a large open office floor and getting really cold from the aircon unit right above me. So I'd call up to have it adjusted (had to set up a problem ticket, etc. etc.) - with the frequent effect that I often felt it was actually getting colder...

This went on for a while until I got the trick of insisting they re-open the original problem ticket. Eventually this hit some time limit where it got escalated and an engineer called to say he was going to come to my desk and check personally. 20 minutes later he calls and says "I'm here, where are you?".

Turns out there was a mix up in the A/C location database between the serial numbers of two units. I was sitting under unit X which had been recorded as being at location Y and vice versa. So I'd call up and they would dutifully increase the set point of the unit claiming to be at location X but was actually at Y and then shortly after that the person at location Y would call up to ask for a decrease at location Y, which would lower the temperature for me at location X.

Took a while to resolve (they actually had to get out the scaffolding tower over the weekend to get into the ceiling space) but never underestimate the power of keeping that same problem ticket open!

Baby Space Shuttle biz chases dreams at Spaceport Cornwall


Based on google maps satellite view the runway looks a bit shorter now. I'm not a pilot but I'm assuming the big Xs on part of the runway (and the general rundown look) mean "don't land on this bit!"

An anti-drone system that sneezes targets to death? Would that be a DARPA project? You betcha


Actually ....

.... from a technical perspective that was actually pretty impressive. Difficult to judge distance/size/scale but both drones were moving, the DARPA one seemed to be swinging around a fair bit but it still managed to hit the other one with a fairly tightly defined blast of pink goo at a reasonable range.

From the article description I was expecting something that just wildly sprayed pink goo everywhere!

The server is down, money is not being made, and you want me to fix what?


Not that exciting but....

While doing my PhD I ended up in the group of (unpaid) BOFHs who looked after the lab's IT equipment and generally helped out with IT support stuff. I was overrunning a bit on the PhD and get a surprisingly stern talking-to from my supervisor about completing my actual research work and stopping the (technically voluntary but someone has to do it) BOFH/IT Support stuff.

Literally the next day he phones up to ask me to help get his printer working!

He had the decency to look at the floor while I was there which could have been embarrassment but could also have been to avoid my massive grin.

(and he did say thank you)

Blue Origin sets its price: $1.4m minimum for trip into space


Yes... and no

Whilst I agree that this is space tourism, plain and simple I do still feel there is scientific validity in some of what Virgin Galactic is (or was - I haven't checked lately) offering. One of their plans was to offer science flights where you will get 5 or 6 minutes of "high quality" weightlessness (*) with your experiment. I don't know if BO is planning on offering something similar though

If you are a scientist and you actually get to sit next to your experiment and drive it for those 6 minutes there is a _lot_ that you can get done. And for the price of flying it to the ISS and training an astronaut to use it you could buy a huge number of 6 minute VG flights...

Obviously difficult to decide if the zero-G research is useful to humanity as a whole (vs. the carbon, etc. costs of the flights) but I generally err on the side of "more research is good" and the carbon foot print of such flights is still probably tiny compared to launching stuff to the ISS.

(*) I think the "vomit comet" flights are good for training and filming space movies but I don't think they provide a stable enough zero-g to compare with the ISS environment and they will always be susceptible to aerodynamic turbulence no matter how accurately they fly the parabola. Because VG and BO will basically get out the atmosphere for those few minutes they should be able to provide something much close to "true" zero-g.

Samsung shows off rollable and foldable displays, suggests they'll arrive in 2022



I wonder how big this will scale. e.g. replace "roll down screen + projector" with, well, "roll down screen"

Dam it: Beaver ate our internet, says tiny Canadian town of Tumbler Ridge


Hmm, this "counting axles" approach doesn't seem entirely reliable. I think the Swiss railways still have a restriction on the number of carriages that a train can have so that the total number of axles is not 256.

(for the obvious reason which apparently wasn't obvious at the time).

On a dusty red planet almost 290 million km away... NASA's Ingenuity Mars Helicopter flies


Re: Why is radio comms so slow?

On wikipedia they state that it is using the ZigBee protocol. I think that is pretty slow but has decent range. Also, they would want something omnidirectional so there is no need to aim antennas, etc. By the time you've done "simple, reliable, omnidirectional, range of up to 1km, etc." the bitrate is going to get quite low.


Re: Long Live Ingenuity!

I think there is a bit of a difference in the "wear and tear" in each case. For Spirit and Opportunity the point was for them to be there for a reasonable amount of time and to travel a reasonable distance to make it all worth while. With a combination of good design, careful operation, making everything a bit bigger/stronger (i.e. "rounding up" on the specs of everything they could) and, to be realistic, a bit of luck they vastly exceeded the design life.

But Ingenuity is a tech demonstrator. It is the smallest, lightest thing that they could build that could plausibly function. If it had failed completely it wouldn't have effected the primary mission (but would obviously have been hugely disappointing for the 'copter team). But the battery is going to get treated really harshly - it's in a very cold environment, it is going to get charged slowly over a day or so (whilst being partially discharged overnight to try and keep everything warm) and then it is going to get _savagely_ discharged during each flight. I'm sure they will be analysing the battery/power data really carefully and optimising everything they can but basically this is textbook "how not to make your battery last" cycling (well, at least the charging is slow I suppose). At some point (sadly soon) it won't be able to accumulate (and keep) enough charge each day to make up for the losses overnight and still have some spare to accumulate for a flight.

But, yes, here's hoping that they get plenty more flights before that happens!

Watch this: Ingenuity – Earth's first aircraft to fly on another planet – take off on Mars


Re: No doubt the conspiracy theorists will be calling 'fake'!

According to wikipedia it is a laser rangefinder: https://en.wikipedia.org/wiki/Ingenuity_(helicopter)

Specifically, one of these: https://buy.garmin.com/en-US/US/p/557294

To be honest, if I was Garmin, I'd have a "As Used On Mars" banner all over that page!

NASA's Mars helicopter spins up its blades ahead of hoped-for 12 April hover


"Red One, standing by"

‘Radiation upset’ confused computers, caused false alarm on International Space Station


I think (but not sure so feel free to correct!) that the ISS is low enough that it is protected by the Earth's magnetic field for the majority of solar issues. I don't know if it is clear whether this incident was Solar or Cosmic radiation though. And obviously, such protection just reduces the incidence, not stops it altogether.

If I recall correctly, although there is an increased risk from long term spaceflight (even in the relatively low altitude ISS), the only time that specific events (such as Solar flares) have needed to be considered was for the Moon missions where the astronauts were outside the magnetically protected zone. I don't recall that any special consideration was given to the electronics but as it was significantly "chunkier" back then (yup, technical term, that is) it may well have been much less sensitive to such things!

I know that solar flares can be an issue for satellites (but not sure whether that is all of them or whether geo-stationary are more at risk, being further out). But, as shown here, computer systems can get messed up by a single bit flip whereas lifeforms are a bit more resistant (but not invulnerable) to similar events.

From Maidenhead to Morocco: In a change to the scheduled programming, we bring you The On Call of Dreams


Gatwick -> Edinburgh ?

As a lowly summer student (i.e. the cheapest person to pay w/e rates to) at an engineering company I was asked if I'd take a small suitcase of "special diodes"(*) from the London labs up to Edinburgh so they would have them for production start on Monday morning. So I booked some flights, arrived at a fog-bound Edinburgh airport, handed over the suitcase (at the airport), turned round and went straight back into departures. The buildings were high enough off the ground that, due to the fog, I could genuinely claim to have not seen Scotland at all on the trip.

Slightly odd thing was that the senior manager who had arranged it all, turned up at my house on Sunday evening to pay all my expenses and overtime (and rounded it all up generously) in cash. Which leads me to suspect that someone, somewhere had massively screwed up and needed it cleared up in as off-the-books way as possible so, although I was merely the cheapest pawn, I had contributed to saving someone's job...

(*) not a euphemism! Genuinely was a pack of very special, very expensive (probably zener) diodes...

SpaceX wants to slap Starlink internet terminals on planes, trucks, and boats – but Tesla owners need not apply


Wait, what? I remember watching that documentary "The X-Files" years ago and they could get mobile reception literally where ever they were. Middle of a remote forest, large desert, etc. it didn't matter they could whip out the old flip-phone and make a call.

You're not suggesting that I was misled are you?!

Retro Microlympics concludes with possible reopening dates for UK computer museums


Re: Elite

Yes! Buy this book and read it.

(and weep after you've read the chapter on how the UK had orbital launch capability and then just gave up)

Scottish rocketeers Orbex commission Europe's largest industrial 3D printer to crank out 35 engines a year


Re: Suddenly..

Upvote for reminding me of the authors name! Hopefully I can find a copy of the anthology now. For some reason I thought they were Harry Harrison as their styles are similar.

(also upvote for the AC who prompted this!)

Hero to Jezero: Perseverance, NASA's most advanced geologist rover, lands on Mars, beams back first pics


Yes, they do have a good track record of over-achieving in that department.

But I would imagine the hazards of flying are much greater than wheeled transit and a lot more random - any rc drone/aircraft owner could tell you about that!

I've been trying to work out how "fragile" this thing might be in comparison. On the one hand martian gravity is lower so, for any given height, a fall results in a much lower impact velocity. On the other hand the atmosphere is very thin so it is harder to create lift therefore it has to be as light and hence flimsy as possible. On a further hand, the blades will presumably have to spin extremely fast so if they do hit anything (e.g. on a wonky landing) that will be bad...

This is presumably why they haven't set any particular science objectives for it and it seems as if it is more of an engineering experiment - "can we do this? how well does it work? and, if it does, what have we learned and what future capabilities can we design and plan for?"

I don't know if they will have the bandwidth for live video (presumably they will still record some) but it will be awesome to see it fly (or get the point-of-view) for the first time!

Chromium cleans up its act – and daily DNS root server queries drop by 60 billion


Re: hang on

Also, why were they hitting the root servers? Shouldn't it just be using whichever DNS the machine it is on is configured to use?

Disclaimer: I only have a basic understanding of the DNS infrastructure so there may well be a good reason for this!

Bye-bye Bridenstine: Outgoing chief leaves NASA in good shape, though Boots on Moon by '24 goal looks doubtful


Re: Been there done that..

Probably true but it does depend. I forget where the article was (so I'm probably going to get the figures wrong) but for all the amazing success and endurance of the spirit and opportunity rovers, the science they did could probably have been carried out by a pair of humans in a "few days". Now, the time ratio is not the same as the cost ratio so can still be argued as uneconomic but the other piece that humans bring is adaptability. Robotic and automated missions rely on you have a pretty good idea of what you are going to find before you get there. Yes, you can do a bit of reprogramming but fundamentally if the conditions are not what you expect then there is nothing to be done (c.f. the mars drill that they have finally had to give up on). Likewise, you are only likely to see what you were looking for. Again I forget where the article was but I think some tests were done in the "Mars Yard" (putting a stuffed animal behind a rock, etc.) to see if the rover operators would notice and, mostly, they did not.

Of course the humans do have an additional advantage that the resources and equipment necessary to deliver them mean that they are likely to have a wide range of equipment and tools to try something else whereas, by design, the robotic missions are pared to the bare essentials - so this isn't an entirely fair comparison.

Still it is nice to think that us meatsacks could still have an important role such as moving the mars drill out the way, dropping a metal pole in, smacking it with a rock a few times and then saying "there you go buddy, I've loosened it up for you, have another try"...

UK Space ponders going nuclear with Rolls-Royce: Hopes are to slice the time it takes for space travel


Re: A cheaper fix...

Apparently it is routine that the 'nauts gather round the access hatch of the cargo vessels when they are first opened to get a few breaths of the "fresh" air.

(presumably they've done all the safety checks on it first, etc.)

Titanium carbide nanotech approach hints at hydrogen storage breakthrough


Re: Why not just use...

I _think_ the only currently feasible chemical option would be https://en.wikipedia.org/wiki/Sabatier_reaction which makes methane.

But this still needs hydrogen as an input although presumably doesn't require energy for compression/cooling at least.


Re: It's not just the storage

Yes, this: "For these reasons both approaches have merit and should be pursued"

Suspect the main issue will be keeping the debate and decision making practical and science/engineering based. Political and popular discourse is already descending to "Batteries Suck! No! Hydrogen Sucks!" and, even if you are more aware of the technicalities, some of this stuff is hard to compare.

On the face of it, sitting in a car with a steel tank of 700 Bar flammable gas sounds like a bad idea. But we happily accept sitting next to an un-pressurised tank of flammable liquid. Is that better or worse?

Similarly the first time I realised I was sitting on a battery that was being charged at >100KW I did have a brief moment of "gosh, that's like 35 kettles being on at the same time"...

BOFH: Switch off the building? Great idea, Boss


Building Power / Users ?

I must say I do like the idea of a contribution to my personal electricity bill based on the office building consumption divided by the number of staff...

SpaceX Starship blows up on landing, Elon Musk says it's the data that matters and that landed just fine


Re: SN8 flight was to test multiple concepts in one go

Based on the two hops (where I think a couple of the legs got crushed pretty badly despite the relatively low speeds) it didn't seem likely that they were going to work anyway. You may be right about the deploy as, on the hops, the legs did deploy much earlier and higher, but possibly this time it was intended to be later and lower so was in the dust cloud (shortly before it became a fire cloud)

I genuinely don't think SpaceX will care that it blew up - SN8 was already out of date compared to the next set of prototypes so, if they didn't move it off the launch pad by launching it, they were probably going to have to move it with the crane and dismantle it.

This way they have learned a huge amount and also possibly reconfirmed that the landing legs weren't up to it - which they already suspected (based on some Elon tweets)


^ this too. A modified Starship is one of the three proposals for NASAs moon landing. The Curiosity (and soon Perseverance) rovers on Mars I think are already on the mass limit of where a parachute is vaguely plausible to slow it down. Even then they had to use the (rocket powered) skycrane for the actual landing. So this is just cutting out the mass of the parachute. It would still do the skydive manoeuvre, because why not it might help a bit, but will use the rockets for landing. And then taking off again later. I would imagine that even if you did have a big enough parachute, guaranteeing a vertical landing could be tricky...


^ this. Wings and all the other stuff are dead weight except for the last couple of minutes of the mission. You already have some rockets so a little bit of extra fuel for them to use is worth it.

UK reveals new 'National Cyber Force', announces Space Command and mysterious AI agency


"Backroom Boys" by Francis Spufford has a chapter on this. All round a good book (until you realise how much we just gave away or gave up on).

Interestingly, given that it is now clear that economic/cheap spaceflight is only plausible with reusability, I wonder how the Black Arrow combo of RP-1/HTP would fair by modern standards...

Test tube babies: Virgin Hyperloop pops pair of staffers in a pod, shoots them along 500m vacuum tunnel


Re: It's the faults that would scare me!

Worrying, yes, but given this is intended to compete with high speed rail, would being in a 200+ mph train be any better?

Did Arthur C. Clarke call it right? Water spotted in Moon's sunlit Clavius crater by NASA telescope


Re: Clavius crater


(round here, of course, this is a _good_ thing)



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