The race to build the first space hotel is hotting up, but at what cost?

The old adage about nothing in the world being more certain than death and taxes - usually attributed to Benjamin Franklin, but probably coined by Daniel Defoe - has its own hollow ring of inevitability.

Nonetheless, it is worth trotting it out once again in the aftermath of one of the big anniversaries to have illuminated 2019. For just as the eventual failure of the body, and the clipping of 20 per cent from your monthly pay packet, are inavoidable facets of human life, so the half-century celebrations of the 1969 moon landings were always going to spark the resurrection of a specific sort of science-fiction speculation: When are we all going to space, and where will we stay when we do?

If your own answers to the above two questions are a disgruntled sigh, a bored shrug, and a swift return to day-dreaming about whether it's too soon to be booking a summer holiday in Greece (it's not), then you probably don't need to read too much further. But if you have ever gazed at darker parts of the sky with a desire not just to go there, but to hang around for a while once you've arrived, then recent "developments" may be of note.

Those inverted commas around "developments" are there for a reason - because the concept of a functioning hotel in space is still floating a fair distance into the future. 

As it has for a while. It is now almost two decades since the US entrepreneur Dennis Tito became the first "space tourist" to pay his own way - a reported US$20million (£15.4million) - up to the International Space Station (ISS), in 2001.

But since then, although several intrepid souls have followed him into the firmament - seven travellers made the same journey aboard a Russian Soyuz spacecraft between 2001 and 2009 - the route into orbit has remained out of reach for those who do not have many millions in the bank. Russia halted its space-tourism programme in 2010 as the growth in size of the crew needed to man the ISS ate up any spare capacity that had existed on its rockets. Virgin Galactic, meanwhile - although only planning to carry passengers into sub-orbit, rather than keep them anywhere near it - seems only marginally closer to its stated goal of sending flights up into the blue than it was when it was founded in 2004.

Yet the global reminiscence about Armstrong, Aldrin and giant leaps for mankind have reinvigorated a wider interest in space that was a feature of almost every dinner-party conversation in the Seventies. And where there is interest, there tends to be investment.

"We haven’t seen this kind of excitement about space since the Apollo era," Frank Bunger told Reuters earlier this week. Bunger is the CEO of Orion Span, a California-based aerospace start-up which has grand plans to go where no private company has gone before - and convey paying guests to its own commercial space station. What's more, he has every confidence that this jump into the future is, in fact, almost a matter for the present tense. "It sounds kind of crazy to us today because it's not a reality yet," he continued. “But that’s the nature of these things - it sounds crazy until it is normal.”

Bunger's high-tech baby is known as "Aurora". It could be in orbit within the next two years, and welcoming guests in the next three. That's the ambition, anyway. "Our goal is to make space accessible to all," he explained in a promotional statement released late last year. "Upon launch, Aurora Station [will go] into service immediately, bringing travellers into space quickly, and at a lower price point than ever seen before."

Big talk? Possibly. But while a schedule with "2021" and "2022" scrawled onto it in red ink may be hard to keep to, Bunger is entirely serious that Aurora will not only rise into space, but be a success once it is in position. It will not be huge - it is likely to be about 11 metres long and three metres wide; roughly the size of a private jet. But it will be able to hold up to six people at a time (including two crew members), each of its guests paying US$10million (£7.7million) for a 12-day holiday conducted 200 miles above the Earth's surface - with incredible views and 16 sunsets a day as standard.

What else will space tourists enjoy in return for their not-inconsiderable financial outlay? They will be able float freely around the "hotel", experiencing the joys of zero-gravity. They will be able to play ping-pong in this weightless environment. They will be able to take part in scientific research projects, including growing food while in orbit - and will have the opportunity to talk with friends and relatives back on terra firma, via satellite video links and wi-fi. There will be nutritious meals, and comfortable places for slumber. "With customisable private sleeping pods, top-quality space food and luxury design details," Bunger told CNN earlier this year. "Aurora Station is ushering in a new era of space travel, setting the bar higher than ever before".

Will all this come to pass? If it does, it will certainly not do so without competition - perhaps from the Gateway Foundation, whose own vision of tomorrow, the Von Braun Rotating Space Station (VBRSS), could be - it says - up and orbiting as soon by as 2025.

Another California company, Gateway is currently thinking bigger than Orion Span. Named after Wernher von Braun - an aerospace engineer who worked both for Nazi Germany (which had him arrested and imprisoned) and NASA - the space station will hold far more than six people. If it is built to its intended blueprint, it will be able to host 450 guests at any one time. Timothy Alatorre, one of the architects on the project, has explained that it will be the largest man-made structure in space, with facilities including a gym as well as bedrooms. Unlike Aurora, it will also have its own artificial gravity - at roughly a sixth of the strength of that on Earth. This will be generated by spinning the station around its own core (hence the "Rotating" part of its name) - a pragmatic compromise. “We could easily create Earth gravity on the station by spinning it faster - but you wouldn't be very comfortable," Alatorre told Reuters this week. “The problem is that you can only spin so fast before you start feeling sick.”

No price has yet been mentioned for a stay on the VBRSS, but it seems implausible that it will be much cheaper than the $US10million price-tag attached to a near-fortnight on Aurora. And herein lies the catch. Even if both launches go ahead in their stated time-frames - and even if companies such as SpaceX and Virgin Galactic can provide air-lift upwards - space tourism will be the preserve of the exceedingly super-rich until far into the future. A summer break in Greece will still have appeal in 2030.

Of course, there have been starry-eyed schemes before. Go back more than half a century - not just to the moon landings, but to the restless post-war optimism of the Fifties - and you find the remarkable tale of the Lunar Hilton, the 100-room retreat that the hotelier Barron Hilton wanted to construct on Earth's only satellite. It would have had a piano bar and an observation deck - and there were semi-serious discussions about building it more than a decade before Armstrong and Aldrin touched down. Work on it is, as yet - you may have noticed - unstarted. Will the last weeks of 2069 find us all floating about in our spacesuits, and at a reasonable price - or will we still be wondering if Aurora Station will ever launch? The future, as ever, is up in the air.