"The Dragon doesn't need any of those things. Its purpose is to take a few people into orbit and back"

Where are they going to go when they get to orbit? The ISS won't be there after 2020 or so. Bigelow is a lot of hot air. The Russian ISS-remnant will be serviced by Soyuz. So what's left for Dragon/Falcon apart from space tourism?

The Dragon alone can't build an ISS Mark 2 or even a Mars Expeditionary vehicle, it needs a workshop vehicle/microstation to dock to for the crew to do anything significant in orbit (and have a shower, use the toilet etc.). That's what the Shuttle was, as well as being the crew vehicle. A Falcon Heavy could launch such an unmanned microstation but they cost a lot of bucks so having it recoverable to be refurbished and reused would be a good idea. A heatshield re-entry system to splashdown on something that large would be cumbersome so tiles or another lightweight heat protection system on a lifting-body or winged vehicle would be preferable, like the X-37 or the new ESA re-entry testbed article flown recently on a Vega. Thus is the Shuttle reinvented, better and shinier than before with the lessons of the past learned.

Every Shuttle flight needed spacewalks, the cargo bay, the spacelab, the manipulator or other features sadly lacking in a people-only spacecraft like the Dragon until the ISS was ready for habitation. The ISS couldn't have been built without the Shuttle though, not without a (non-existent at the time) SLS that could throw a complete space station or large ready-to-go part of it with spacesuit airlock(s), manipulator arm, power systems etc. into orbit in one launch. Even then a "fork-lift truck" spacecraft like the Shuttle would probably have been needed to move shit around as more parts arrived in orbit -- the ISS is over 400 tonnes as is, nothing larger than about 16 tonnes in one piece.

Either a workshop/fork-lift spacecraft would have been recoverable to Earth as the Shuttle was or it would have been disposed of into the upper atmosphere and a new one built, furbished and launched every time a new task needed to be accomplished. The Shuttle was there to do that job, repeatedly.

Sure the Shuttle never succeeded in what it was originally designed for, nor was its launch tempo (50 launches a year was mooted at one time!), costs or other factors met. It did the job though when the ISS was built and when it was laid out in the early 70s nobody knew the ISS was going to exist at all. There's lots of Monday-morning quarterbacking about how things should have been but having the Shuttle to hand made things a lot easier when it was needed.

The Dragon has no airlocks, no space (heh) for spacesuits, no external cargo capacity in the service module (although they're working on it) to carry spare parts, no manipulator arm to tether and position EVA personnel around the Hubble or other large space infrastructure item like, say, an ISS Mark 2. It's a minimal spam-in-a-can meatbag-to-orbit delivery system, not a lineman's truck with a cabover as the Shuttle was.

The Shuttle's OMS fuel load could be maxed out to 18 tonnes if lots of in-orbit manoeuvering was planned at the cost of a reduced payload bay manifest. Most flights it didn't carry that much fuel but it didn't need to be rebuilt to take max fuel/oxidiser if the next flight necessitated it. Any Dragon plus disposable workshop mission is going to cost more and take longer as each workshop will have to be built and individually tailored to the expected mission's requirements. The other option is to build a son-of-Shuttle recoverable workshop/living quarters spacecraft, a bit like the autolanding X-37, but I don't see any budget for that anywhere.

How much would it cost to build and launch an 50-tonne "workshop" spacecraft to do the Shuttle's job and then ditch it into the upper atmosphere after every flight? A lot more than a billion a flight, never mind the extra launch of a manned capsule to dock with the Space Workshop module.

A recoverable and reusable spacecraft with the capabilities to do the same job as the Shuttle would need heat-tiling, some aerodynamic appendages to control re-entry and oh look! it's a Space Shuttle!

Saying that the Shuttle concept was laid out in the days when scheduling launches and docking in space was not as refined as it is today so the workshop was integrated with a manned "capsule" and living space and everything went up in one stack. One use (about the only repeated use I can think of in fact) for Falcon Heavy would be to launch a unmanned son-of-Shuttle "workshop" which would be recoverable to autoland on a runway for refurbishment and repurposing after spending a few months in orbit being visited by Soyuz/Dragon/SLS crews.

At the moment Dragon's only intended purpose is ferrying crews to the ISS but the space station is wearing out and its days are numbered. Once it is decommissioned then what? Dragon can only put meatbags in space, it can't do anything else unless there's somewhere for them to work and live. The Shuttle was an inelegant solution to that problem but it worked for 133 and a half flights. Sure it cost a lot but spaceflight generally costs a lot, thousands of bucks per kilo into LEO.

The "space truck" was actually a complete space station. It had living space for seven people, airlocks for EVAs, a shower and a toilet as well as having 20 tonnes of cargo space in the back of the "truck" and a payload arm/manipulator.

The Shuttle had considerable cross-range capability once in orbit with up to 18 tonnes of manoeuvering fuel (twice the total payload of a current Falcon 9) and could stay in orbit for up to a month if needed with a reduced crew. It did most of the heavy lifting of the construction of the ISS in orbit and carried out multiple Hubble repair and upgrade missions. At the end it came back down to Earth and landed on a runway.

The Dragon capsule is purely for canned monkeys with no toilet, no shower, no airlocks and no EVA capability. It has no cargo capacity, no manipulator arm, limited cross-range capacity in orbit and limited endurance and it certainly can't be used to carry out maintenance flights to the Hubble or its successors.

There's a version of blindfold Go where both players use the same colour of stones. They can see all the stones placed on the board so it's theoretically still a full-information game. They remember who played which stone or they can work it out from the pattern.

"Amazon has close to no overseas presence outside of English speaking countries."

Well, apart from France (75 million people), Germany (80 million), Japan (120 million), South Korea (50 million), Spain, Greece, Italy, the Scandinavian countries, Holland, Belgium etc. etc.

Add them up and you'll find the populations of Amazon's non-English-speaking markets are way larger than the English-speaking nations. The total number of customers and total sales may be lower -- Japan, for example has Rakuten/Tenso as a serious competitor to Amazon.co.jp for online sales -- but they're out there and selling to anyone with a credit card and a keyboard whatever language they speak.

Raw uranium ores are a lot more radioactive than pure uranium oxides like yellowcake (U3O8) because of all the shorter-lived isotopes that have built up in the ore bodies from a billion years or so of decays of U-235 (700 million years) and U-238 (over 4 billion years). The other thing is that solid lumps of uranium are a good shield against radiation and the alpha particles resulting from decay events a millimetre or two under the surface are unlikely to escape the lump of metal and be dangerous.

Don't forget Japan which has delivered cargoes to the ISS using their home-grown launcher. They also launched a spacecraft, Hayabusa deep into the Solar system to rendezvous with a comet and return particle samples back to earth. The Hayabusa-II followup mission launched in December 2014 and it plans to return samples of an asteroid as well as landing three small hopping "rovers" on it for close-up study of the surface.

How are they going to be guided? They're solid slugs of metal, they've just had ten million amps pumped through them and the equivalent of a short-range EMP imposed on any instrument package on-board and they're red hot from resistive losses. Just how do you intend to guide them to target 200 km away after all that? A large Acme-brand magnet from the Roadrunner cartoons perhaps?

Unpowered unguided shellfire at extreme range is piss-awful inaccurate. Here's an image of the shot pattern from the Iowa BB's 15" guns; 25000 yards is only 14 miles, 36000 yards is about 20 miles.

http://www.fas.org/man/dod-101...

For this test the ship was sitting still, it wasn't travelling at 25 knots rolling in a heavy sea. In contrast a Tomahawk missile fired from a smaller cruiser or even a submarine from hundreds of miles away could hit an individual window in the Pentagon.

Unless railgun projectiles can be terminally guided like, say, aircraft-launched missiles then you can expect their fall of shot patterns to look like the Iowa's, only ten times wider since they'll have ten times as as long to deviate in flight over the extended range.

The problem with blackout during a hot re-entry from orbit is plasma from the heatshield or tiles (in the case of the Shuttle) blocking radio signals at Mach 20 or so (about 6 km/second or thereabouts). This wasn't the case of the Falcon first stages as they were never going fast enough in the atmosphere to produce any plasma. If any of them had then the bottom of the stage would have melted since it's mostly lightweight low-melting-point alloys. Those sorts of temps would also have damaged a lot of the motors, the actuators, the guide fins etc.

As for the accuracy thing, again it was not a re-entry from orbit and the stage had guidance systems to bring it down to the barge, much as the Shuttle never had a problem finding the runway and painting the centreline during its landings. What puzzled me more was the speed at which the stage hit the barge. It should have been a lot slower, even with the failure of the guidance fins.

It's the other way around. Extra neutron captures in plutonium created in a nuclear power reactor produces Pu-241 and by decay, Am-241. The bombardment of U-238 with deuterons doesn't produce Pu-241. No Am-241 in the sample hence it was not produced in a reactor. That's the theory.

It's more complicated than that, there are ways of producing very pure Pu-239 in a reactor but the extreme purity of the sample in question seems to mitigate against it being produced by the capture of fission neutrons in a reactor.

That's weird, I just read your "but 4k monitors aren't ready yet.." assertion on a 4k monitor...

I've got my old 1440p resolution display in portrait mode as a sidekick to my 4k monitor (a Dell PQ3214 bought in a Black Friday sale). I can throw edited page proofs etc. onto the portrait display while I work on the rest of the editing project and have browser windows, notes, a spreadsheet or two, image galleries etc. on my main screen.

I'm not sure I'd be happy running on just a portrait monitor and nothing else but as an adjunct to a decent-sized landscape display it works fine.

The Ariane V has been launching two geosync large satellites simultaneously for quite some time but the upper satellite is carried on a frame/shield called SYLDA that fits around the lower satellite. Usually the two satellites being launched are different sizes and shapes. In this case it appears the Boeing satellites are roughly identical and docked together in their launch fairing saving on the weight and volume of the carrier. However the lower satellite has to cope with the mass of the upper satellite during launch. There is probably a strongback frame of some sort running through the lower satellite to handle that increased load.