They are planning a Mars fly-by so apart from the problem of providing life support for 500 days there is actually less deltaV required than for the Apollo moon missions because they don't need an extra 4.5km/s to land and takeoff from the moon's surface.

Almost all the fuel will be used at earth escape, and only minimal maneuvering thrust from there on so a modified dragon capsule is probably capable of doing the job. Launched on a Falcon Heavy rocket that might cost less than $200 million in total (costs $140 million for a Falcon 9 Dragon launch to LEO).

The dragon capsule can carry 6.6 tonnes of payload and is designed to survive in space for up to 2 years, so has more than enough capacity to support 2 people. And while some may claim that 2 people cannot survive in a capsule that big for a year and a half for psychological reasons, that is just bollocks - but it will be easier if they pick people with the right sort of temperament.

1/ They have the bomb.
2/ They are desperate for money, and have few qualms, and seemingly little good judgement about doing whatever it takes to get money to maintain their fucked up internal power structure. $2 billion per year exports at moment, but $3 billion imports and $20 billion external debt
3/ There are numerous groups in the world who do not like the west (some 'terrorists', some countries) who could probably raise a few hundred million to a billion dollars to buy a nuclear bomb.
4/ Short of hitting them with a pre-emptive nuclear strike North Korea cannot be invaded/stopped without massive risk/destruction to South Korea, Japan, and possibly USA (nuclear weapons + ICBM), also huge danger from China if it comes to a shooting war/invasion.

Pretty good chance that North Korea will sell a bomb to someone to use on a western city. Iran and pakistan are also moderately dangerous. I wouldn't feel particularly safe living in coastal USA cities, or Israel for that matter in the next 20 years.

If your business has to pay more than offshore competitors for the tools it uses then you have a major problem.

Strong case could be made that any company that sells it's software at lower cost in other countries should be legislatively compelled to match that within your country, but would need someone powerful (like EU or WTO) to make it happen.

Historically large differences in relative wealth (gini coefficients) are strongly correlelated with the breakdown of society and revolutions etc. The US is already pretty high in OECD terms, and has pretty appalling stats in access to health care incarceration rates, crime, educational outcomes for poor kids etc that tend to go along with having a high gini coefficient. You have a huge and growing pool of americans who have little to no real hope of being able to get their kids into even the middle class.

The Trust Fund Kids of the Walton family (Walmart) have a net worth equal to the poorest 90 million US Americans. (That absolutely staggers me).
http://en.wikipedia.org/wiki/Walton_family
Now assume for a moment that they have little or no interest, aptitude, or industriousness in using that capital in an efficient manner to grow further enterprises (ie improve the country) but simply want to live as emperors - I don't know if that is actually true, but in some cases it may be. Such colossally rich individuals who have not created that wealth themselves but have simply chosen their parents carefully are in effect a useless nouveau aristocracy.

That equity would be far better in the hands of hard working people further down the chain who could use it to start businesses, improve infrastructure, develop technology, educate their kids etc, but given the size of their money pile and the relatively small birth rates of today, there is a strong possiblity that their dynasty could maintain or even with minimal effort grow their total holdings as a proportion of GDP over the coming decades/centuries.

I have no problem with entrepreneurs getting rich, but that wealth needs to be returned to the rest society within a couple of generations if you want to have a dynamic society based upon egality, fraternity and liberty (that is what the French revolution was all about) and not a world of gated communities and violent ghettos. How you go about constructing a society that achieves that is left as an exercise for the reader, but massive inheritance taxes (above some level) seem like a pretty useful component.

... run away from our new hedge pruning, tree trimming, log cutting, Edward Chainsaw-hands overlords.

The criminal justice system in the USA appears to be almost entirely geared towards extracting more tax money to pay for bigger and more heavily populated prisons and building name recognition for politicians and prosecutors, and as a result is paying a colossal and unnecessary and is a world wide laughing stock. I and a lot of my friends would not consider living in the USA as a result of this Criminal-Justice system run amok, scary thuggish police, (dreadfully overpriced yet widely inaccessible health care system is also another black mark).

The Criminal-Justice system needs to be reformed towards delivering the best results for society as a whole, not venal special interest groups. Disqualify anyone within the Criminal Justice industry (prosecutors, police, guards) from running for public office for at least a few years after they end employment, also disallow campaign contributions from private prisons, and guard+police unions.

The biggest and fastest growing threat to humanity is disease and religion (including anti-human greens). Think 12 monkeys or "The White Plague" (frank herbert).

in 2011 a researcher invented a flu strain with human mortality of probably about 50%. A small number of motivated nut jobs, perhaps even a single person with a couple of million dollars could probably replicate this with far less visibility than for example nuclear weapons programs. There are a large number of highly educated people in the world who would like to wipe or cut down the human population by a large degree.

Even a worst case global nuclear war is unlikely to kill so many. There is nowhere on the planet more than 2 days travel away. Nowhere to hide, and no means of preventing such a thing coming to pass if released in a mobile 1st world population centre with millions of motivated individuals desperate to escape an epidemic.

Marianas trench is 11km deep. A neutrally bouyant gun barrel inclined at about 20 gives a barrel length of 30km and is relatively cheap to build (a couple of billion for a few meters diameter).

If you immerse the astronauts in water (body hugging 'bath') they can easily withstand 10-20g for 15-30 seconds. That gives you 2.5-3.5km/s muzzle velocity, and a relatively simple rocket to prvodie the additional 5-6km/s - similar to current rocket second stages.

The gun can also be used at higher g to launch inert payload to orbital speeds without less rocket propulsion.

Guns are ok for lower speeds (up to perhaps 2-3km/s) but ram - accelrators are better than light gas guns for higher speeds.

Leaked figure from IPCC AR5 report shows just how far off even updated IPCC model predictions are:
http://wattsupwiththat.files.wordpress.com/2012/12/ipcc_ar5_draft_fig1-4_with.png
note that the grey bands are nothing more than an attempt at IPCC arse covering in light of failed predictions, the temps are consistently riding the low side and even outside of the coloured prediction bands, and most importantly the temperature trend is much much lower than predicted.

The IPCC's models are massively over estimating the impact of increased CO2 - unsurprising when they assume large positive water vapour feedback that don't appear to operate as they assume in practice, and temperature suppressing aerosol impacts that appear to have been overestimated too. They also don't have the capacity to model other dominating effects (like PDO and AMO oceanic cycles, solar variations etc), and have shown no ability to model or explain historical variation covering a 3 C band during the current interglacial - including eras like the Medieval, Roman and Minoan warm period and the little ice age.

An honest question: how many years of no temperature rise would it take for the catastrophic CAGW thesis to be rejected? We've had about 15 years of near stasis, and recent results show that the heat isn't 'hiding' in the ocean - it simply doesn't exist, though CO2 continues to rise. So just how many more years are needed for the IPCC to let go of the millenialist thermageddon fantasy and bring the temperature rise predictions back to a more realistic level (seems likely to be about 1-2C rise for a CO2 doubling).

So Current costs in France: $6500/kW installed.

http://en.wikipedia.org/wiki/Economics_of_new_nuclear_power_plants
Current cost in China $2000kW (using latest AP1000 design), targeting $1000/kW in near future. Which is why China is going to dominate the global nuclear industry. The cost reductions enabled by building large numbers of plants of the same/similar design are huge.

The changing tides on the moon are month long solar tides due to the moon being tidally locked to the earth. And the smaller diameter of the moon means that even those tides will be weaker, tidal accelerations being proportional to the distance from the centre of mass cubed.

recent data doesn't show any increase in rate of sea level rise:
http://sealevel.colorado.edu/
looking at the decadal rate of increase it has actually been falling off for last 5 years:
http://www.masterresource.org/wp-content/uploads/2011/09/sea_level_rise_fig1.jpg
doesn't appear to be any significant alteration in rate of rise over last 100 years, rate of rise in 30's-60's was about the same as current:
http://www.oceanclimatechange.org.au/content/images/uploads/2012_sea_level_fig1.jpg

A rather big factor that needs to be taken into account is that since the 1950's there has been a massive amount of ground water abstraction for agriculture that is estimated to contribute something like 0.4-0.8mm/year to sea level rise (15-25% of total).
http://news.nationalgeographic.co.uk/news/2012/05/120531-groundwater-depletion-may-accelerate-sea-level-rise/

Richard Muller was never a skeptic, but is a publicity hungry showman. He claimed he was a skeptic so that he could stage a road-to-Damascus style conversion that would play well in the media. Eg check out this interview from 2008: http://grist.org/article/lets-get-physical/

"The bottom line is that there is a consensus — the [Intergovernmental Panel on Climate Change] — and the president needs to know what the IPCC says. Second, they say that most of the warming of the last 50 years is probably due to humans. You need to know that this is from carbon dioxide, and you need to understand which technologies can reduce this and which can’t."

He was critical of Mann's woefully poor hockey-stick analysis just as all scientists and statisticians are, though at least he made those critical comments in public (where most scientists were too afraid of fall-out)

That said his work on BEST (reanalysis of historical global temperatures) is decent science.

Kourou vs Canaveral gains typically about 2% payload. For a $100 million dollar launch that is worth nearly $2million. Not a big deal if you are a US company, but given Europe's lack of alternatives it is definitely the place to be for Arianespace

Instead of developing Ariane 6 Arianspace could just buy up 51% of SpaceX after their IPO - then they can mostly do what they want with it.