This paper reviews the prospects for the development of commercial hotels in space, and shows that - having already begun with the recent commercialisation of the space station 'Mir' - it is increasingly accepted that this is likely to become a lively new field of business within little more than a decade. The key enabler is the availability of low-cost access to space through the operation of reusable passenger-carrying launch vehicles, the development of which requires investment equal to just a few months' of existing space budgets. When this happens, competition will lead to rapid development of progressively more exotic facilities as companies exploit the unique environment of space to provide guests with ever more entertaining services. The paper discusses some of the civil engineering topics that will arise as orbital accommodation grows from assemblies of prefabricated modules, to large structures assembled in orbit, to rotating structures offering 'artificial gravity', and eventually to buildings on the lunar surface.

Although there are many economic difficulties facing the world today, there is also a prospect of a new 'Golden Age' of world-wide economic growth based on humans' ever-growing accumulated knowledge. However, in order to achieve this it is necessary to build on sustainable foundations, which requires economic policy-makers to aim in the right direction. One most important requirement is for economic policy-makers in richer countries to facilitate the growth of the new industries that are continually needed to re-employ those leaving older industries as they automate progressively and migrate to lower-cost countries. An important direction which has recently begun to receive recognition as a potentially major new field for commercial activity is passenger space travel. The two following predictions show the scale of the potential importance of this new field in the coming years.

Prediction 1: "Popular space travel will do for the 21st century what aviation did for the 20th century". Passenger space travel will grow from zero to more than $1 trillion/year, creating new employment for tens of millions of people, and profoundly changing our daily life on Earth.

Prediction 2: "Within little more than 10 years, space will be the front line of the hotel industry". Space hotels will be a focus of media interest, and they will show rapid development as they compete to attract guests with more and more advanced facilities exploiting the unique environment of space.

Many people are skeptical about these possibilities, since they think that tourism in space must be impossible "...because if it was possible, NASA would be doing it". However, this logic is based on an unfortunate misunderstanding about the behaviour of government space agencies.

Sadly, government space agencies have no interest in helping taxpayers travel to and from space. They currently receive budgets of $25 billion every year from taxpayers (Nasa $14 bn, Europe $6 bn, Japan $3 bn, plus a few billion in Russia and other countries) - but they use less than 1% of this for work that is relevant to making passenger space travel available. They are not trying. However, this is not because passenger space travel is not feasible.

Because Nasa's leaders have decided not to make it accessible via the Nasa web-site, it is not widely known that Nasa published a report 'General Public Space Travel & Tourism' [O'Neil et al, 1998] which confirms that space tourism is feasible and realistic. The report's major conclusions were:

1. almost anyone will be able to travel to and from space without difficulty;
2. sub-orbital space flights can start with today's technology; and
3. tourism will become the largest business activity in space. The report also recommended actions by Nasa and other US government offices to help this development which will bring major economic benefits [O'Neil et al, 1998].

However, the present administrator of Nasa is not implementing the report's recommendations - and other countries' government space agency leaders take the same view: that they need not use any of their funding to help make space accessible to taxpayers! This policy is completely different from governments' role in aviation, which has for many decades been to aid the growth of commercial passenger air travel - which has grown into a global industry with revenues of nearly $1 trillion/year, creating employment for tens of millions of people. By contrast, although commercial passenger space travel is known to be feasible, space activities are still mainly government activities funded by taxpayers at $25 billion/year, and they employ far fewer people.

This economically disastrous situation is a left-over of the cold war, during which Nasa was established to compete with the Soviet Union in publicly visible 'space missions'. For decades during the cold war space agencies grew used to receiving enormous government budgets with which they did not have to earn a profit - and they are very reluctant to change. This problem has now reached such a critical level that proposals are being made to take funding away from space agencies and give it to organisations that will develop passenger-carrying vehicles [Rogers, 2000]. It is increasingly recognised that the aviation industry has the experience and capabilities to do this successfully, and collaboration between space and aviation interests is consequently also specifically being advocated [Collins et al, 1999].

The traditional viewpoint of government space agencies is now due for revision as governments progressively cut back economically unproductive expenditures, and the public increasingly expresses its desire for space travel services. However, at least until government space agencies are radically reformed, it is a major mistake for the general public to rely on them to make space travel services available like air travel - since they are extremely reluctant to give up their comfortable and privileged position of receiving $25 billion every year from taxpayers, none of which they even have to pay back - let alone earn a commercial rate of profit.

In contrast to space agencies, in recent years it has been increasingly recognised that the general public is extremely interested in traveling to space, and a growing number of companies and organisations are working to realise this possibility.

Since 1993, the author and colleagues in several countries have performed market research, with striking results. Within the constraint of minimal budgets, market research in Japan, Canada, Germany, USA and Britain shows a consistent pattern: most people say they would like to visit space, and a large proportion say they would be prepared to save up even several months' salary to pay for a trip [Collins et al, 1995].

From our data we estimate that once the price of a week-end in space falls to about $20,000 the demand will reach many millions of passengers/year. Although this may sound expensive, saving $100/month would accumulate enough to travel to orbit between 10 and 20 years from now. The president of the US Adventure Travel Society has opined that even at $500,000/passenger, space flights will be a very popular form of 'adventure travel', which currently generates $120 billion/year in the USA alone [Mallet, 1999]. However, there remains a great need for more market research.

Many people assume that a vehicle like the US 'space shuttle' is required to carry passengers to space - which costs several hundred million dollars/ flight. But the 'space shuttle' was designed for government purposes, including defence. Today's passenger airliners use basically the same technology as military aircraft - but they are optimised for passenger carrying, and are far cheaper per passenger. Likewise, a vehicle optimised for passenger space travel will be far cheaper per person than the 'space shuttle'.

Starting in 1993, the Japanese Rocket Society ( JRS), a private professional organisation, has been working on a Space Tourism Study Program described in a large number of reports and papers. An initial effort was the design of the ' Kankoh-maru' which could carry 50 passengers to low Earth orbit ( LEO) at 200 km altitude at a total cost of some $1 million/flight - enabling a price of around $28,000/passenger, provided that demand reaches 700,000 passengers/year [ Isozaki et al, 1994]. This is very close to the demand shown by market research. Encouragingly, instead of being criticised as being too optimistic, the JRS cost estimates have been citicised for being too high. For example, the 'Venture Star' launch vehicle design by Lockheed-Martin Corp. would have a payload 4 times that of Kankoh-maru, but the estimated development cost is the same - about $6 billion. Most strikingly, this investment is just 3 months of space agencies' annual funding from taxpayers.

Figure 1: Comparison of Lockheed-Martin Corp's X-33 test-vehicle and 'Venture Star' satellite launcher with Japanese Rocket Society's ' Kankoh-maru' passenger vehicle.

As recognition of the potential of space tourism grows, there is a growing range of activities towards realising it. For example, a report by the American Institute of Aeronautics & Astronautics ( AIAA) concluded: "In light of its great potential, public space travel should be viewed as the next large, new area of commercial space activity" [Bekey, 1998].

In 1999 the head of the Office of Commercial Space Transportation (OCST) at the US Federal Aviation Administration (FAA) stated that she is working to enable entrepreneurs to "...open space to all kinds of activities: thrill-rides, vacationers, industry and even trips to the Moon..." [ Smith, 1999].

And in April 2000 the US Transportation Secretary announced that the OCST's budget is to be doubled [Slater, 2000].

The subject of space tourism is also receiving increasing attention from professional societies such as the American Society of Civil Engineers [Various, 1988-2000]. And in 2000 the first university course on space tourism started in the Department of Hospitality and Service Management at Rochester Institute of Technology. The subject also receives ever-growing media coverage in Europe, the USA and Japan: this is very welcome in awakening the general public, politicians and the business community to the extraordinary opportunities that are being wasted today by the misallocation of government funds for 'space development' to activities with the least economic potential.

In order to understand the potential role for civil engineers, a most important fact is that in all the market research to date the majority of people say they would like to spend several days in orbit, rather than only a few hours [Collins et al, 1995]. Consequently, in order for space tourism to reach its full potential, it will be essential to provide accommodation in orbit - that is, space hotels.

The numbers show impressive potential. It is easy to calculate that when the number of people staying in orbit for a few days reaches 100,000/year (which the JRS estimates could happen within 11 years if development of Kankoh-maru started soon), the number in orbit simultaneously will be about 1,000 people. This will require several hotels accommodating well over 1,000 people. When the number of passengers reaches 1 million/year, some 20 years from now if serious efforts start soon, there will need to be accommodation for more than 10,000 people in orbit! Since no-one has identified any other space activity that offers anything approaching this level of demand, we reach a conclusion that is still not widely appreciated - that the hotel industry is going to become the largest employer in space.

A booming space hotel industry will generate business for all the different activities involved in the hospitality industry as it becomes the 'front line' of humans' expansion into space. Similar to hotels on Earth - or cruise ships, which they will also resemble [Fawkes, 1999] - orbital hotels will develop progressively, starting simple and then growing in size and capabilities almost indefinitely.

In 1998 the head of Nasa stated that "...within 50 years a space hotel is not inconceivable." However, already in the year 2000 the company MirCorp is marketing the Russian space station Mir as a hotel. In doing so, MirCorp is pioneering the new world order for the space industry, and has demonstrated that asking the head of Nasa about space hotels is like asking the head of the Air Force about package-tours: he has no useful knowledge of the hotel industry - which is a commercial activity tens of times larger than the space industry. Of course, until reusable passenger launch vehicles become available, the cost of travel to Mir will remain very expensive, some $20 million per passenger, preventing the market growing much. But MirCorp already have their first customer.

With reusable launch vehicles, once passengers can travel to orbit for less than $50,000, trips to orbital hotels will grow rapidly. Dedicated orbital hotels will then cost hundreds of millions of dollars rather than billions - the same as major hotels here on Earth - making them attractive propositions for commercial investment. Furthermore, they offer the only commercial use of the space station technology developed by government space agencies.

From market research, most people wish to look at the Earth from space - and everyone who has done so has said that it is extremely impressive to see our home planet Earth against the blackness of limitless space. For some guests the philosophical or spiritual experience of meditating on humans' apparently unique situation in nature - as intelligent beings who have evolved to consciousness and are now on the verge of moving out towards an apparently limitless future in space - will be extremely rewarding. Learning from one's own physical experience about humans' situation in the universe will surely be educational in the most profound sense - and is entirely appropriate for the start of a new century and millennium in which humans are going to spread out from our cradle, Earth.

On quite a different level, living in weightlessness or 'zero-G' is said to be hilarious. All activities are transformed, even the most ordinary ones such as undressing or brushing one's teeth - when things don't drop but float when you let go of them. In addition to daily living, there is a limitless range of possible entertainments to take advantage of this. For example, by playing with water in a dedicated room small groups of guests can witness the true fascination of 'zero G' - and children can try unlimited tricks on each other! For more energetic guests, all sports will be fascinatingly transformed in weightlessness. Perhaps the ultimate will be the possibility of actually flying like birds by using fabric wings, once there are sports facilities 50 metres across [Collins et al, 1994].

The technology required to design an orbital hotel is much simpler than that in a passenger launch vehicle, or even a space laboratory like the ' International Space Station' since there is no need for high-speed computers and data-communication systems, advanced research equipment, accurate attitude-control and so on. Early living quarters require no more than what has already existed for decades; later on, 2nd and 3rd generation hotels will be much larger and will include resort hotels, entertainment complexes and sports centres. The following lists the major steps in this evolution.

1. Prefabricated modules

   The first phase will comprise prefabricated modules which can be launched as units and connected in orbit, operating in 'zero G' like Skylab in 1973 or Mir today. Some designs may include inflatable sections, which can be an economical structural method.

2. Module clusters

   In order to accommodate more guests, clusters of modules will grow ever larger. An interesting feature of orbital hotels is that it will be possible to add new rooms progressively as required, which is not practical for hotels on Earth, which usually remain as they were constructed.

3. Large chambers fabricated in orbit

   In order to be able to offer new services, larger chambers will be fabricated in orbit. For economy, prefabricated modules will have standard diameters, constraining the range of interior design possible; once the step is made to fabricate larger chambers in orbit there are few constraints on their shape, and no clear limit to their size. Buildings in micro-gravity can be very light: the only significant structural stress is that of internal air pressure of a maximum of one atmosphere. One attractive approach will be to fabricate large structures from large numbers of identical structural units.

   One use of large orbital structures that seems like to become popular will be sports, which will be fascinatingly different in 'zero G'. The large economic impact and the huge global popularity of major sports events such as the soccer 'World Cup' is an indication of the potential revenues that could be earned from novel sports events in an orbiting stadium. For this reason, preliminary conceptual work has been done on the design of orbiting 'sports centers' [Collins et al, 1994], including three different facilities, a gymnasium [Collins et al, 1996], a rotating swimming pool [Collins et al, 1998] and a sports stadium 100m long [Collins et al, 2000], as discussed further below.

4. Rotating structures

   In surveys, many people express a preference to stay in orbiting facilities that offer 'partial gravity' as well as zero-gravity. In order to enable guests to experience partial gravity, space hotels can be set rotating. In principle this is a simple idea, which has been under consideration within the space industry for decades. However, it adds complexity and constraints to the design and construction of a space hotel. The rate of angular rotation must be limited in order to minimise Coriolis forces acting on guests moving radially, which could feel unpleasant, as discussed in [Matsumoto et al, 1989]. Interior design principals for rotating accommodation facilities are discussed more broadly in [ Hall, 1999].

5. Co-orbiting facilities

   As the number of different LEO facilities grows, there are good reasons for siting them in a small number of common orbits [Collins et al, 1986]. In addition to improving their overall safety, this will open up possibilities for local travel between co-orbiting facilities, using 'orbital taxis' and even 'orbital scooters'.

6. Lunar hotels

   Since people travelled to the Moon 31 years ago, it is clear that lunar tourism is technically feasible - the only challenge is to reduce the cost enough to generate a large market. Like other space activities, the cost of lunar travel depends primarily on the cost of launch to LEO: once travel to and from LEO is routine and large-scale, travel to and from the Moon will be a straight-forward development. Conveniently, traveling to the Moon economically takes 3 days, and so one-week and two-week round trips are likely to become popular services. (It is worth noting that, by contrast, round-trips to Mars take 2-3 years, and so they will probably never become a significant business.)

   A large amount of research has already been performed in the field of civil engineering on the lunar surface, including experiments such as making concrete from lunar soil; extracting oxygen and metals from lunar rock; designing buildings of various types; designing dedicated machinery for use on the lunar surface; and a wide range of robotic and other research, much of it published in conference proceedings of the American Society of Civil Engineers [Various, 1988-2000].

Once launch costs have been reduced sufficiently for orbital tourism to become a substantial business, the cost of all activities in space will fall proportionately, and the cost of employing staff in orbit will fall to a level comparable to employing construction staff in the North Sea or Alaska. Preliminary consideration has been given to construction projects that go beyond the simple docking together of pre-fabricated modules, as is involved in the ' International Space Station'. Study of these projects raises issues in several new areas that are ripe for innovative work - and which will both draw on and in turn contribute to civil engineering on Earth. The following is a partial list of such topics.

A central issue is the overall design of large structures to remain air-tight over long lifetimes in the vacuum and 90-minute thermal-cycling environment in LEO. Drawing on design approaches for aircraft, ships and pressure-vessels, they will be designed for ease of monitoring and maintenance, and the design methodology will evolve as progressively larger structures are built, as also occurs in terrestrial engineering practice.

The construction industry on Earth already employs robots for a number of tasks, which is growing steadily as robots become more sophisticated. Use of human-tended robots derived from these will be cost-effective for a range of assembly-related activities in orbit, particularly such repetitive tasks as connecting standard structural components together, and checking features on the external surfaces of structures.

The possibility of progressively adding sections to orbiting structures is a major difference from terrestrial buildings. It will add a new dimension both to the business side of design and management of orbital hotels, and to the engineering side, since it will be necessary to monitor and control hotels' centre of mass (CM) continuously for such basic tasks as attitude-control and station-keeping.

In contrast to the narrow airlocks used on the Mir space station today, there will be a need for wide airlocks - of some 2m by 1m or more - in hotels and passenger vehicles. This is an obvious case for the development of a world standard, in order that all vehicles should be able to dock together - although such a standard is likely to be 'multi-part' in order to enable a range of utilities to also be transferred through airlocks.

Due to the relatively high cost of carrying resources such as water to orbit, hotels will use at least partial water-recycling systems, perhaps 80%, even in the early stages, since the technology is already well developed on Earth. In addition, water can be split using solar electricity into hydrogen and oxygen, which are key rocket propellants, and this is likely to become a significant LEO business activity.

While a pool is likely to be a popular guest facility [Collins et al, 1998], the water it contains has a large mass - of the order of 1000 tons, making its launch cost a major investment. The possibility of using the water in a pool for multiple uses, including as shelter from radiation, and reserve for propellant manufacture, could help to amortise the cost, making such multi-functional design important.

The demand for water and propellants at orbital hotels could be a key step in developing the lunar economy by creating demand for exports of lunar ice, if it exists in a readily usable form, or oxygen extracted from lunar rock [Collins, 1998] - though water delivered from comet remnants is expected to be very price-competitive [Sonter, 1998].

An interesting challenge will be designing the plumbing systems for hotels with hundreds of guests and staff. For example, what kind of pumps will be best for the novel task of moving sewage along pipes in micro-gravity while preventing the possibility of any reverse flow? The design of both fresh-water and waste-water systems will need to be integrated with systems for recycling water to different standards for various purposes, and with the compacting of residual waste for return to Earth, or for use in recycling plants separate from the hotel.

In hotels containing a rotating zone, there will be at least one rotating joint between the rotating and non-rotating zones, which will probably be several metres in diameter in order to allow movement of large numbers of guests. Such a joint will also need to provide considerable structural strength and vibration-damping, depending on the overall hotel design, and carry a number of utilities, including electric power, air-conditioning and plumbing. These requirements seem likely to be sufficient to create a substantial niche for the engineering firm that gains a lead in this area.

Where large numbers of guests use a facility like a stadium, there will be a need to be able to move them safely. Various different techniques have been proposed to date, including handles moving along guide-rails, moving cables, air-tubes and others, but until more research is done, it is difficult to judge which means will be preferable.

Preliminary study of a 100m-long sports stadium led to the conclusion that the very large single air mass – some 300 tons - that it will contain will require the development of a new design philosophy different from that used in civil engineering on Earth, due to differences between weightlessness and the terrestrial environment [Collins et al, 2000].

In order for orbital hotels to reach their full potential, an important area for innovation is the development of construction standards and related certification services for commercial buildings in orbit. In order to finance an orbital hotel to be operated commercially for customer accommodation, insurance will be needed, for which there will be a need for design and construction standards, training and qualification systems, and related certification services like those in the building and shipping industries.

Organisations such as Det Norsk Veritas [Det Norsk Veritas] provide these services for the merchant marine industry, and it has been proposed that the same services may be offered for space hotels by a new organisation 'Space Veritas' [Collins et al, 2000]. It remains an open question which arm of government will play the leading role - Civil Engineering, Aviation, Shipping, Transportation, and the Coastguard service are all candidates. 40 years of space activities have developed experience in the design of certain types of equipment, but this has not been assembled in the form of commercial standards, due to the dominant but non-commercial behaviour of government space agencies [Collins, 2000].

As in cruise-ships and airliners, a space hotel is likely to have a captain with wide legal powers, and his staff are likely to be divided into Engineering and Hospitality functions. The responsibilities of engineering staff will cover all aspects of the hotel, and might be divided into the following specialities: electrical systems, communications, plumbing, environmental control, structure, station-keeping, traffic control, and safety and security. Civil engineers' will play significant roles in many of these, but their involvement seems likely to be greatest in structural engineering and overall design and planning activities.

In addition to the topic of overall structural integrity, ensuring the safety of orbital hotels will concern two issues in particular - avoidance of collisions, and protecting the health of guests and staff.

As in all transportation systems, there will be a need for traffic control systems in space in order to avoid collisions between vehicles. Initially the volume of activity will not be large, but it seems likely to grow rapidly, and so active traffic control will become necessary [Collins et al, 1986], [Collins, 1999]. In the USA the FAA is already promoting this concept [Anon, 1999], but to date governments of other countries have short-sightedly ignored their invitation to participate in joint studies.

Another danger is that of collision with 'space debris' - discarded remains of satellites and space vehicles that continue to orbit the Earth. Collisions with these are known as 'hyper-velocity impacts' and are extremely destructive due to their high impact-speeds of 10 km/second or faster. However, the steps necessary to remove all space debris are well-known, the most important being the introduction of a law of liability for damage caused to property in orbit [Baker, 1988], and a law of 'space salvage' analogous to the long-established law of salvage at sea [deSaussure, 1985].

The reasons why such basic laws have not been introduced yet are the lack of demand because human activities in space are still very small-scale, and the reluctance of government space agencies which are responsible for most of the debris in orbit. However, demand for orbital hotels will lead to the enactment of these laws, which are clearly in the public interest and should be no more controversial than the same laws which are already in place on Earth, on the sea and in the air. Once these laws are enacted they will create strong economic incentives for the collection of most debris.

In order to remove all orbital debris, it will also be necessary to remove smaller pieces of debris - typically small pieces of metal some centimetres across, remaining from exploded space vehicles. It has been proposed that these should be removed by using high-powered lasers to decelerate them so they re-enter and burn-up in the atmosphere, a project which may require public funding [Bekey, 1997].

The FAA has already drafted medical guidelines for passengers traveling to orbit, and they expect almost anyone who would fly on an airliner to be able to travel to space without difficulty [Antunano, 1999]. Passenger vehicles like Kankoh-Maru are being designed to accelerate at no more than 3G, which is not stressful for people lying on their backs. Many people who visit space today feel nauseous for some time: although this has been called "space adaptation syndrome" it is merely a form of motion-sickness which is cured by normal anti-emetics, and so guests will be encouraged to use medication which suits them, as they are on cruise ships. Hotel guests will generally stay in orbit for only a few days, and will therefore receive radiation equivalent to an average annual dose of X-rays on Earth, and of no danger.

Most hotel staff will probably work on 2-month rotations, during which 'zero-G' temporarily weakens muscles which do less work than on Earth. Hotel staff will also receive significantly more cosmic radiation than on the Earth's surface (as do airline stewardesses), and so for safety they will be treated as a new class of 'radiation worker', like staff who work in hospital X-ray departments or nuclear facilities. However, radiation safety is well-understood, and no astronauts have suffered from radiation sickness, although many have spent months in orbit.

From the future possibilities for evolution of space hotels outlined above, it is clear that their development and operation will generate business activity in a range of fields - hotel design, manufacture, launch, assembly, maintenance, repairs, upgrading, security, plumbing, waste disposal, travel to other facilities, and others. In addition, the idea of staying in a space hotel is popular with all age groups, giving good potential for market segmentation as in the terrestrial hotel industry - adventure tourists, wealthy guests, elderly guests, families with children, special interests (education, astronomy, medicine, religion etc), sports enthusiasts, youth and others, thereby creating a wealth of new business opportunities in this new field of hotel development.

In order to understand what this could mean in overall business terms, Figure 2 shows how far it could grow by 2030 - provided that investment begins soon. The JRS study concluded that with an investment of some $12 billion over 10 years (that is, less than 5% of planned government space agency spending over that time), passenger travel services to orbit could start within 10 years, thereafter growing by 100,000 passengers/year/year. In this case there would be some 1,000,000 passengers/year by 2020. We can be sure that, as passenger numbers grow, prices will fall and tourism companies will develop ever-better facilities in orbit, so it seems probable that demand will continue to grow strongly, perhaps reaching 5 million passengers/year in 2030, for a turnover of more than $100 billion [Collins, 2000].

Figure 2: Potential space hotel development by 2030, from [Collins, 2000]

On this scenario, some 40 million people in total could have traveled to space by 2030 - or perhaps 2% of the middle class population of the time. Yet in market research, most people say that they would like to travel to space, and in addition a large proportion, particularly of younger people, say that they wish to do so several times. Consequently serving just 2% of the middle class population will not satisfy the market, and so traffic levels even higher than this are conceivable. Five million passengers/year will entail some 40,000 guests staying simultaneously in orbital accommodation. Assuming an average occupancy rate of even 80%, this will require capacity for some 50,000 guests in orbit, probably involving more than 100 hotels, and a construction rate of several new hotels every year.

It is notable that airlines already carry more than 20 million passengers every week, and expect to be carrying several times this number by 2030. It is also notable that, on present budgets, government space agencies would spend $750 billion over the next 30 years - more than enough to pay for this scenario, but with none of its economic benefits. Realising this highly attractive vision requires a change in the leadership of the space industry, and close collaboration with the aviation and civil engineering industries.

The space industry is currently plagued by a lack of demand for their skills: they have almost no business except launching satellites on converted missiles, and government 'missions', totalling barely $40 billion/year world-wide, and showing little growth. In addition, the launch industry, which is already unprofitable, is preparing itself for a "bloodbath" due to falling demand and growing supply [ deSelding, 2000].

However, in view of the exciting possibilities described above, this is truly a case of 'starvation in the midst of plenty' in which the space industry's narrow-mindedness and lack of commercial focus has trapped them. What is required is for business to start to target the hundreds of $billions/year which surveys show that the general public are willing to pay as consumers of space travel and accommodation services, instead of the tens of $billions provided reluctantly by taxpayers for government 'missions' - by developing an orbital hotel industry.

From the above discussion it is clear that travel to and from space hotels is not a distant dream, but an exciting, near-term possibility - if the right steps are taken. Above all, this requires governments to recognise the enormous cost that their space agencies are imposing on taxpayers due to their lack of interest in the potential of the tourism and hotel industries to create commercial demand for accumulated space engineering skills.

The key to the huge and growing commercial success of the tourism and leisure industries worldwide is the successful integration of the different viewpoints and interests of travel companies, airlines, cruise lines, hoteliers, construction, finance, civil engineering and others - and this successful collaboration is very visible as a corner-stone of the economy of North Cyprus. In the same way, getting those with spacecraft engineering experience to contribute to economic growth through the economically highly valuable task of realising a passenger space travel industry will also require collaboration between the travel industry, aviation, cruise lines, hotels, civil engineering, finance and others.

The development of an orbital hotel industry is such an attractive prospect that vigorous efforts should be made to realise it. In particular, the hotel and construction industries - which are 100s of times larger than the space industry, and commercially highly successful - have a vital role to play in stimulating the development of passenger space travel so that it grows into a major new industry in the 21st century, enriching the world as air travel did in the 20th century.

Due to the very small amount of preparatory work that has been done towards the establishment of a space hotel industry to date, almost any work aimed in this direction is valuable - technical, commercial, financial, legal, and at the policy level. Timely work is likely to be well rewarded by gaining a competitive advantage for those involved. Working in the largest business field in space - orbital hotels - will surely be one of the most fascinating and sought-after forms of civil engineering employment in the 21st century.

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