The biggest problem with space is the first 1000km.

CM,

re ttbn...I understand the view from some that prioritising Earth's problems over space exploration makes sense. But that wasn't what he said. He just pooh-poohed the notion of seeking to become a multi-planetary species. That's entirely different. It also fails to understand that doing one doesn't preclude the other or that conquering space would help solve the problems on Earth. The computer you're read this on was made possible by the advances from the space programme.

"One of the paradoxes of space 1. it's hugely expensive 2. it's an enormous opportunity."

It WAS hugely expensive. Starship's IFT4 flight just went a huge step to resolving that.

"The biggest problem with space is the first 1000km."
Not even the first 1000km but the first 100km. It is said that 50% of the cost in getting to the moon (c 400,000km) is the first 100km. Again SpaceX all but resolved that.

"Certainly the Moon, Mars, and the Asteroid Belt are candidates for exploration. The inner planets Venus and Mercury are probably too hot. They talk about "The Goldilocks Zone"."

They are candidates for human habitation. As are one or two of the gas giant's moons. Venus and Mercury will absolutely be explored but not by humans but by robots. Robots are of course another by-product from space exploration and are another field Musk is leading. Jensen Huang, Nvidia CEO has said recently he expects major break-throughs in humanoid robots in the next 2-3 years and that they'll be as prevalent and more consequential than the car. Musk talks of 20 billion robots by 2050. The energy for that will have to be sourced from space.

Already humanoid robots are working autonomously in the Tesla factory. As the world's human population falls to around 4 billion by 2100AD, the economic gap will be filled by robots. (That is, 4 billion on earth. How many will be elsewhere is uncertain).

There are many inflexion points in human history, most of which we missed at the time - the wheel, the arrow, the alphabet, the ability to sail the oceans, the piston, steam engines etc etc. When the mainframe computer first became available, it is said that the 'experts' at IBM - at that time the leaders in electronics- thought they might have been able to sell 6 worldwide. They thought Gates was a fool for taking royalties for MSDOS rather than a lucrative sale because they had no idea how ubiquitous the PC would become.

I feel privileged to live in one of those inflexion points and to be able to impress its important on my grandkids - where were you when IFT4 flew?

mhaze- Thanks for the information. Kudos.

http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

You might like the single stage rocket equation above. It gives theoretical limits on rockets. You can put it into a spreadsheet and vary the parameters to control different targets such as 'height of arc', 'cross section of rocket', impulse, payload, burntime, etc. The limits on cost seems to be that of the fuel. I think the costs below are for LEO rather than HEO orbits. From memory the baseline for US rockets was $20,000/kg and for India $10,000/kg- so even $1000/kg would be great ($100/kg would be brilliant), and could open the possibility for high schools to do space based projects depending on the red tape especially with micro-satellite technology. Remember the UK teacher that launched the camera via weather balloon to 30km's taking pictures of the Earth's curvature.

mhaze,

You left off, Gutenberg and the printing press, Farnsworth and the television. There is some conjecture as to who invented what. Ford didn't "invent" the production line, nor did Gates invent the personal computer and as for Jobs and the mobile phone, nah. We could go one forever about great things invented, Appert and the canning process. The Americans claim the Wright brothers as the inventors of the aeroplane, many would not agree.

As for the Forum Luddite, he's just purchased his first pair of spats and a straw hat, ttbn, you old trend setter!

"The limits on cost seems to be that of the fuel."

I'm not so sure about that. While its very true that new technology and fuel mixes have significantly improved efficiency and reduced costs, the major factor seems to be the reusability of the SpaceX family of craft. By recovering the boosters essentially in tact, the cost of construction is reduced by orders of magnitude.

While those countries and companies who don't recover their boosters have seen rather good drops in costs of launch, SpaceX have seen dramatic savings. For example, estimates are that the current Chinese rockets cost around $4000/kg into LEO whereas Falcon 9 is a touch over $2000/kg, Falcon Heavy a touch under $2000/kg. SpaceX estimates Starship will be around $200/kg.

And yes, at that cost, myriad groups and organisations will have access to sending all sorts of things up there for experimentation and exploration.