One fuel and oxidiser inlet into one turbo pump equals one engine. It had four combustion chambers but no redundancy or any way of shutting off a single chamber if something failed upstream. More thrust than the F-1 even in its later form and a lot more efficient in terms of Isp. It's a great bar bet, "what's the most powerful rocket motor ever flown?" but getting Americans to admit the F-1 was number 2 in the list is always a pain as they try to weasel out of it.

There have been several new launcher motors developed over the past decade (Vega and Epsilon, for example)

I thought both of these were simple solid-fuel designs?

Simple and cheap, both costing less to put a small payload into orbit than SpaceX charges and with lower overheads. The first Epsilon flew with only eight people controlling the launch and there was no launchpad fuel handling etc. needed. I don't know how much a Falcon-9-scale solid fuel launcher would cost to develop and produce though.

Another modern engine design I forgot to mention is the Japanese LE-7 LH2/LOX motor used on the H-2 series launchers. Very good Isp figures, significantly better than Merlin but a lot more expensive and non-recoverable.

The problem is that if they launch over the sea and then try to recover a first stage back to land it is going to burn a lot of fuel reversing course before it falls out of the sky. That extra fuel will eat into payload-to-orbit, as will the landing leg system and all the other gubbins needed to soft-land it meaning that it can only be realistically used on small-payload launches which means less financial return on such flights. It would be a lot easier just to buy off some local Texas politicians and get permission to launch-to-land across Texas without having to reverse course in mid-air. My alternate suggestion was that Elon should buy a surplus aircraft carrier and soft-land the first stages on that mid-Atlantic instead. It would piss off Mr. "Americas Cup" Larry Ellison into the bargain as well as ticking off another entry in the Bond megavillain bucket list.

The SpaceX Raptor engine as specified in the Wikipedia article will produce about 60% of the thrust of the Soviet-era RD-170/171, the most powerful rocket engines ever flown with 1.8 million lbs of thrust (using those weird American Imperialist units) and still in service for Zenit launches. The methane-burning Raptor will have, assuming they get all the bugs out, about 5% better Isp than the RD-171 which burns RP-1/LOX like the existing Merlin series engines.

There have been several new launcher motors developed over the past decade (Vega and Epsilon, for example) as well as new revamped versions of older designs like the Vulcain 2 used on the Ariane V. The Merlin series has improved immensely since the first crude version of a few years back with the latest, the 1D having significantly better Isp characteristics although it still lags behind the much older RD-180 design in both in fuel efficiency and in terms of thrust.

As for not pushing the envelope SpaceX is starting development work on methane-LOX rockets which promise some benefits in terms of throw weight over RP-1/LOX but it's something other folks have investigated before without that fuel combo making an impact on the launch market. It does mean they will have to go fully-cryogenic but with less hassle than LH2 involves. It could still turn out to be a costly dead end for them.

The recoverable first-stage flight system SpaceX is proposing is meant to launch from a purpose-built launch facility in western Texas with the landing spot for the first stage somewhere to the east of there. This involves flying over populated areas during the first part of the flight profile and that is going to raise some eyebrows. It's Texas though where killing people in industrial accidents is regarded as a cost of doing business without pesky Federal government regulations getting in the way of making money.

The Saudis are planning to build out a lot of nuclear power stations over the next couple of decades which along with solar thermal power plants will be used to power desalination plants currently fuelled by oil and gas. Other Middle eastern nations are planning similar facilities, some of them combined nuclear power generation and desalination systems utilising the "waste" heat from the reactors.

The most expensive single part of a nuclear power station is the containment building and support structures for the reactor vessel itself, something that also costs serious bucks. Those are the two parts of a power station that can't be economically replaced during the plant's lifetime. Everything else gets swapped out and replaced over the reactor's lifespan, pretty much. Pumps, steam separators, turbogenerator units, control systems, transformers, switching gear etc. last for a decade or two or three and then get replaced and/or refurbished. It's part of the cost of operating any power plant, the same thing happens with coal and gas plants depending on the hardware involved. A steam turbine turbogenerator set will last 25 or 30 years, for example. In the case of 1970s vintage reactors the old analogue control systems have mostly been upgraded to digital systems with finer control and better reporting, new sensors etc.

As for reusing a site this is being done sometimes but in other cases the grid demands have changed over the decades and a new greenfield site close to a new urban area that's doubled in size in the past fifty years might be better than one closer to, say, a place like Detroit.

The US military tried operating small nuclear power plants in remote land bases such as the South Pole site and even one in Greenland (the Iceworm project). They were finicky, difficult to keep working and generally an economic and logistical failure. It turned out to be simpler and cheaper to fly liquid fuel to such bases to power generators as well as supplying vehicles, aircraft etc.

The WHO numbers are estimates, there aren't real dead bodies like there were at Aberfan or the real body count at various coal mining operations in China and the third world generally. Even the West with higher safety standards has dozens and sometimes hundreds of deaths in coal mines each year -- the single-incident high body counts are widely reported (12 dead in the Sago mine WV in 2006, 29 dead in the Pike River mine in New Zealand in 2010 etc.). The death of one or two people at a time barely breaks the surface.

If the nuclear power industry was slaughtering workers at that rate there would be a world-wide outcry declaring it totally unsafe... wait, there is a world-wide outcry declaring nuclear power totally unsafe. Coal, not a whimper. Weird that...

You can point to, for example, the Aberfan disaster and say "Coal killed a hundred kids" or to the death toll from coal mining and transport year on year and say "Coal killed these workers" (China proudly announced the death toll from coal mining had fallen below 3000 per annum a couple of years back. It used to be a lot higher). That's on top of the mercury, cadmium, radon, sulphuric acid fumes, dioxins, beryllium, arsenic and the thousands of tonnes of other toxic wastes spread through the atmosphere and over agricultural lands and deposited in rivers and oceans every year which kills and maims people who don't work with coal directly. But nuclear power is worse somehow.

Both the Allies and the Axis forces sank millions of tonnes of loaded oil tankers during WWII, not to mention similar tonnages of warships each with many tonnes of fuel oil on board. One of the submerged museum ships at Pearl Harbor was still leaking fuel decades after it was sunk in 1941. As far as I know this extended and untreated oil spillage has had little long-term effect on sealife and the general health of the oceans worldwide.

You mean like "640kB of RAM should be enough for anyone?"

Intel are reducing power consumption and maintaining performance faster than ARM can improve processing power while keeping power consumption down. The current version of the iPad has a lot more processing power than the first one did but it has a battery three times bigger to give it the same endurance between charges, in large part because the newer ARM chips suck more power than their predecessors did.

Intel-based tablets like the Iconia W series (i3/i5) or Toshiba Encore (Atom quad-core) have the same endurance as ARM-based tablets with similar battery capacities while running a full-fat desktop OS rather than a phone OS with delusions of competency.

Light-water, heavy-water and carbon moderated power reactors only breed U238 up into Pu239 and Pu240 by "accident", so to speak. They get a few percent of the total energy they produce from fissioning these products in-situ. Breeders meant to produce surplus fuel or "burn" waste require much higher fluxes, usually achieved in a small physical volume hence the higher temperatures involved and the use of sodium, lead/bismuth, helium etc. to conduct away the heat. The LFTR concept requires this high flux density, whether of moderated thermal neutrons or a mixture of fast and thermal neutrons while at the same time having the radiological problem of the high-temperature fuel being less constrained in liquid form.

Generally we've discovered that very high neutron fluxes (thermal, fast or a mixture of the two) in restricted volumes required for high levels of breeding in reactors and the attendant high temperatures tend to break things, cause leaks and fires and expensive shutdowns. At the same time reactors that work on the basis of moving fuel around (mostly pebble-bed designs) have not had a happy time of it even with lower neutron fluxes and larger working volumes in the core compared to out-and-out breeder designs. LFTR combines both of these iffy concepts.

Steam pipes leak all the time in light-water reactors, usually in the steam generators in the case of PWRs. This isn't a radiological problem as the cooling/moderating water isn't radioactive as it never comes in direct contact with the fuel and its waste isotopes which are ceramic pellets housed in sealed tubes. The steam loop runs at about 400 deg C or thereabouts at high pressure. In the case of LFTR and other breeder designs the coolant loop is at up to 700 deg C at which point most steel alloys have lost half their tensile strength compared to room temperature. Breeders that have broken their cooling loops in the past released molten sodium or helium but this had never came in contact with the fuel or its waste products so it was not particularly a radiological hazard. This is not the case with LFTR, of course.

"You could get the experimental platform for a couple of orders of magnitude less money."

No you couldn't, demonstrably. If they could build an ITER-scale reactor for one-hundredth the price they would have. Large-scale sustainable high-Q fusion is difficult. It cost billions to build and operate JET and it was never meant to beat breakeven (Q > 1) but it's come the closest to that of any of the major tokamaks with a couple of seconds of fusion with a Q of about 0.6 back in the 1990s. Heck JET wasn't even built specifically to do fusion, it was mainly supposed to be for plasma research but it got repurposed as plasma control and generation techniques improved. ITER, if it works as planned and the physicists haven't dropped a decimal point here or there, is a fusion reactor which will eventually run with Q >= 10 for several thousand seconds at a time. Maybe.

The "E" in ITER stands for Experimental. It's a testbed platform for trying out stuff and seeing how it breaks, a rig to make mistakes on and gain knowledge. There are nebulous plans to build DEMO and the later PROTO which will be power generating fusion reactors but they'll still be less than fully-commercial designs, just another step closer to the rollout of workable and cost-effective fusion power generation. Nothing is guaranteed though.