They have worked out their cost/kg and found it to be lower - and had their sums checked by third parties. I have the feeling this project is largely not being taken seriously because Americans don't pay attention to anything outside their borders (and generally refuse to believe any worthwhile advance comes from outside the US)

They have built something. A precooler that can cool incoming air from 1000C to -150C as it comes into an engine intake at Mach 5, and is light and small enough to fit into an aircraft engine. This is the main part of the vehicle that is a big unknown, and they have shown it works in view of experts from government and industry.

Because Reaction Engines are not NASA and its not the 1970s anymore? You seem to be assuming that SSMEs are the cheapest LH2 engines that could ever be made (wrong - see RS-68, RD-0120 etc.) and that NASAs procedures for turning them around are optimal.

SpaceX started with a lot of money behind it, the support of NASA, and they are doing something very conventional (multi-stage LOx-Kerosene rockets) albeit better than the competition. Reaction engines are aiming at what they claim (with good reason) to be the biggest advance in propulsion since the jet engine. Snarky crap on slashdot is quick enough to write; R&D takes a long time.

They have specced billions to get to a flying spacecraft that is ready to be sold to vendors. The money they have got gets them to their next step; a ground test of a full engine. At that point they will be able to unlock more funding as the risk will have gone down. This method has got them this far; they secured funding from BAE and the UK government by demonstrating that the key enabling technology - the precooler - works.

If you think saving money on LOx is in any way the aim of Skylon, you have demonstrated your utter inability to grasp basic rocket science. Its about saving mass; and Skylon does a hell of a lot of that. So much so that (by the estimation of all the third parties who have looked at the design - including the UK government, ESA, DLR and recently the USAF) it can achieve SSTO operation. It takes off and lands like a plane, so no need to integrate it each time. That is an advance on even SpaceX - they have to manufacture a new second stage and attach it to the reusable first stage.

I assume you are talking about the SJWs? Those who will descend like a pack of harpies on anybody who dissents from their ideology, and then when they meet resistance, cry "harassment" and get their friends in various media outlets to write factually incorrect articles claiming that the SJWs victims launched unprovoked attacks on them.

"You are all childish and petty"

"You smell and girls don't like you!"

No points for self awareness here.

"Lewis' Law" is what is called a Kafkatrap. If you claim that negative responses to your idea validate it, then you have rendered it non-falsifiable; you have essentially quit the field of argument telling yourself you have won - when nothing could be further from the truth.

The Moon is not better than Mars. It has a much harsher thermal environment due to its complete lack of atmosphere. Mars is very cold - but its pretty consistent. The Moon has wild variations in temperature depending on if you are in sunlight or shade - and the night lasts 2 weeks. The first lunar night it had to endure pretty much killed the Chinese moon rover. Non of the Apollo missions spent a night.

The dust on the Moon is entirely un-weathered, and is likely to present a hazard due to being incredible abrasive. Mars dust is probably easier to deal with

The martian atmosphere provides CO2 - that is 2 useful elements you can get just by sucking it through a pump. Any materials you want to use on the Moon must be mined from rocks, and that is harder.

Finally, the Moon is too close. One goal of an offworld colony is a break from lots of the crap here on Earth. A place where you could conceivably still get a connection to Earth internet (albeit with seconds of lag) makes this harder.

...I'm guessing Ed Regis has never had children?

Read the bottom. He once wrote a book about how the Hinderberg disaster proves that Technology Is Bad.

There have been expeditions to space stations smaller than the ISS, for duration longer than a trip to Mars. He is also wrong about the Hinderberg; hydrogen may well not have been the culprit (this theory was mainly pushed by the Nazis to blame the US for not selling them helium) and in any case the airship industry was mostly killed by powered flight getting better.

You know, that rocket that isn't flying because there isn't enough of market for its payload category...

The technology seems sound. Others here raise concerns but I don't think they are showstoppers. This rocket ought to work. But who will buy it? The Falcon 1 filled a very similar niche and price point to this new rocket, and SpaceX simply couldn't find any customers for it. So why do people keep building these dedicated small satellite launchers? I am guess its because its easy. Your engines can be below the size threshold of various difficult and expensive problems. You don't need such a large launch facility. These companies may figure that, like SpaceX, they can create a tech demo rocket which won't attract payloads and then use it as a stepping stone to a proper rocket. What they seemed to forget is that SpaceX got through some very difficult times via direct injection of Elon Musks own cash, and also with NASA support which might not be offered again.