Seret

Flying is probably a lot more mundane than you're expecting 7499275. I took a flight with a guy who'd never flown before a few years ago. He was really excited and nervous before the flight, but once we were in the air he simply said "Er, it's a bit like being on a coach, isn't it?". And he was right. Taking off and landing are interesting, but the bit in the middle is actually pretty dull.

Pen pals is likely all we could be. Nothing at interstellar distances can be done in "a timely manner". That's just the way it is. If it ever happens it'll be a long, slow conversation that takes place over many generations. That may not be how Hollywood wants it, but it's how the laws of physics insist on it being.

It really isn't. You'll get much better surface finish and dimensional accuracy from machining. Additive layer manufacturing is a useful process, but like all processes it has good and bad points. It's an extra tool in or tool box, it's not a wonder tool that replaces everything else. The invention of ALM will probably rate about equivalent to things like the CNC mill or welding IMO. Very useful, but there certainly isn't going to be a "new industrial revolution" like some of the media are flapping about. The wavelength of light captured by a PV cell determined the material it's made of, btw, not the process used make it.

That's the 2050 estimate IIRC.

Roads are actually surprisingly expensive. A mile of road costs between £10-30million in the UK depending on width, the US seems to do it a lot cheaper at about $2-3million per mile. Initial capital cost is one thing, but if you're talking about something that generates electricity you need to look at the lifecycle costs after you factor in income from generation. A solar roadway would undoubtedly have higher up-front costs, but if it generates enough to cover the difference plus O&M and your discount rate then you've got a viable product.

Taking only Earth as our example it does seem a fair assumption that intelligence is associated more with predators than with prey species. Hunting rewards big brains, but herbivores don't need a lot of mental agility to eat. Plants are pretty easy to outmanoeuvre. However, on the flipside of that is the fact that we're efficient predators because we're social. Physically a human is pretty woeful compared to a Bengal tiget or a great white shark, but our ability to cooperate put us on top. It's quite possible that a high-tech alien species would (like us) be capable of both violence and cooperation.

The times when we have used alternative routes to replace oil in the past have often been due to necessity, rather than economics. Germany during WW2 and South Africa during the embargoes of the apartheid era both developed extensive infrastructure to do without oil. Just goes to show how ingenious we can be in the face of scarcity.

The point is that is shows the rate of increase is slowing. Exponential growth would be a straight line on a log scale, but those lines are flattening out. The middle-of-the-road prediction does have us topping out at about 10-11 billion around the end of the century. The lowball estimate could be a decline to 6 billion. The high estimate is frankly a bit scary, as it shows continued growth at the current rate and we'd be looking at nearly 30 billion. In which case we would probably be as stuffed as Sky_walker was suggesting. I'm not convinced a population crash would have to be an extinction event though, populations cycle in nature all the time.

Er, that's not really what happened. Spilled water from drinks bags was common inside helmets, but in the incident shynung refers to there was a failure that lead to a large leak. Two separate things. Where you might be getting confused is that the fact that water inside helmets was considered routine led them to not identify the water leak as a problem quickly enough.

We can synthesize fuels and lubricants from all sorts of sources, we're not limited to oil.

Only because honey badgers haven't invented the chainsaw.

It's also highly likely IMO that interstellar vessels would be entirely automated. Chances are that if we ever meet an alien, it'll be made of metal. All of our ambassadors we've sent to other worlds have been after all.

Skylon grew out of an earlier project called HOTOL, which has been getting kicked around since the 80s. Considering they don't even have prototype engines yet (and the engines are the easy bit) expecting a flying Skylon in six years is a bit of an eyebrow-raiser.

They probably wouldn't even need to. Conquest is the act of taking political control of a society. What would such control give an alien civilisation? It's not like they could live here themselves. It's more likely that if a spacefaring civilisation wanted something that could only be found on Earth they'd simply come and take it. The technological level required for confident interstellar travel pretty much guarantees that they could raid us with impunity. They'd simply come, take what they wanted and leave, and there's little we could do about it. Think about it, if you were in charge of an amphibious battlegroup and were put in charge of taking something away from a hunter-gatherer society on an island, you wouldn't need to be carpet bombing and charging up the beaches. You'd just send a helicopter to go pick it up, with orders to the boys to only fire if attacked. Straight in, straight out. Easy peasy. Huge mismatches in military capability result in very little violence being required to achieve your objectives.

They pretty much already have by putting an end-of-life date on the ISS. The engineers will have done a pretty exhaustive FMEA exercise to come up with that figure. Like you say, things have to remain subject to reassessment when you're dealing with predictions, sometimes risks can be managed as new tools become available, but in general you can't get away from the fact that as you move down the wrong end of the bathtub curve your risks do start to stack up alarmingly fast.

That's actually not unreasonable. People tend to keep tabs on what jobs are going inside their organisations. Are you specifically looking at aerospace or will you consider other branches of engineering? There's stupid amounts of work in civils and rail at the moment. People like MBDA and BAE Systems are pretty much perpetually hiring if you don't have any ethical problems with working for a defence contractor.

The general assumption amongst SETI folk is that any civilisation that can advance to the point of communication at interstellar distances must have a greater capacity to create than destroy. Admittedly our sample size for civilisations is small so we can't be certain.

I don't think that follows. What would they gain by doing so? Resources? If the resources of Earth were within an economically exploitable distance from them and they needed them enough they'd come and get them whether we were here or not. And if we're not a threat militarily then there's no reason for them to strike pre-emptively. I'm pretty sceptical that military expeditions at interstellar distances would be at all feasible. You can't fight at that kind of range even with the most optimistic wondertech.

The Russians can keep whatever bits they want, deorbit the rest. Build a new one.

Sure, there's a million ways to run a cable. You could also tack it to the skirting boards with clips, or run it up into the loft (or down into a basement) and cross over into the room you want that way. Going inside cupboards and wardrobes is a nice unobtrusive way to move vertically.

There's always powerline Ethernet if you can't run cables, too. Not necessarily a cheap option, but useful sometimes.

I'm sceptical of the whole idea of the Singularity. It seems to be projecting forward based on the same models that led Malthus to predict the imminent collapse of society, and it'll fail to come true for the same reasons. Moore's Law has already broken down, and nothing ever keeps growing indefinitely.

Streaming video at high resolution for watching on a big screen like a TV is the main thing I've been doing on fibre that I wasn't on ADSL. It's really handy for the kids, no need to record shows for them and navigate through the godawful interface on most DVRs, we just jump onto a streaming service and pull down whatever TV they want to watch. Sure, there's no law that says you have to have internet. Whatever you agree to in the contract is what they'll supply. Personally I hugely prefer unlimited contracts, which thankfully aren't unheard of where I live.