And he envisages that once we have colonised Earth orbit, it will not be too long before we explore the solar system and beyond as well

But he explains how a number of key steps need to be achieved first before large orbiting cities can be built

Dr Globus tells MailOnline such a structure could feasible be built by the end of the century, if major national disasters are avoided

These would have artificial gravity on the parts that are rotating

A space settlement would be a large structure like a town or city that would house hundreds or thousands of people

Dr Al Globus, a contractor for the Nasa Ames Research Centre in California, says humanity could soon begin to build space settlements

Humans are now spread across all corners of the globe, but what’s the next step?

According to Dr Al Globus, a Nasa contractor and space settlement expert, he says the next logical move is to colonise Earth orbit.

And, he says barring any major national disasters, we could soon have huge habitats floating around the planet by the end of the century.

Dr Al Globus, a contractor for the Nasa Ames Research Centre in California, says humanity could soon begin to build space settlements. A space settlement (artist's illustration) would be a large structure like a town or city that would house hundreds or thousands of people

Dr Globus is a contract scientist at Nasa Ames research centre and over the years has worked on the Hubble Space Telescope, the ISS, the Space Shuttle and much more.

But a few decades ago his interest was piqued by the possibility of space settlements, leading to him setting up Nasa's annual Space Settlement Contest, which challenges students to come up with designs for space colonies.

Now he’s a major proponent for living in space, and believes that it won’t be long before people are visiting cities in Earth orbit as readily as they travel from London to New York.

WHAT IS A SPACE SETTLEMENT? A space settlement would be a large structure, comparable in size to a town or small city, built in Earth orbit. It would have similar amenities and services to towns and cities on Earth, and would enable people to live in space. The ISS currently houses six astronauts at a time, but a space settlement would have hundreds or thousands of people on board. Future space settlements may also have artificial gravity by rotating around an axis. Advertisement

‘Whether [space settlements] will happen or not is really hard to say. Whether it can happen, absolutely,’ Dr Globus tells MailOnline.

‘If we as a people decide to do it, we can do it. We have the scientific capability, financial capability, there is simply no question we can do it.

‘If no major disaster strikes in the next few centuries, I would be astounded if we didn’t do it.’

He explains how our technological know-how it only going to increase barring an enormous catastrophe like a nuclear war.

‘We could have the first space settlement in decades, certainly less than a century.’

Dr Globus (pictured) is a contract scientist at Nasa Ames research centre and over the years has worked on the Hubble Space Telescope, the ISS, the Space Shuttle and much more. He now also runs an annual competition called the Space Settlement Contest

Dr Globus is a proponent of orbiting colonies, while he adds that others like SpaceX CEO Elon Musk are envisaging a future where humans live on Mars.

As to the actual purpose of a space settlement Dr Globus says it could be just like a town or city on Earth while also providing a way for humans to expand and survive off Earth.

It would be ‘a place to live, raise your kids, where your friends and family have Thanksgiving dinner and celebrate Christmas, and visit Earth on vacation,’ explains Dr Globus.

‘It’s the same purpose as any town or settlement or city has.

‘The way species get endangered and wiped out is by being dependent on a limited environment.

‘Humanity started in East Africa and now live on literally every continent - even Antarctica - albeit for a small time.

‘We live in snow, jungle, deserts, savannahas, forests; we have spread out about as far as we can spread out, and the next step is to move to space.’

SpaceX CEO Elon Musk (left) has been building and launching rockets with the goal of making access to space easier. He hopes that one day humans may be able to colonise Mars (right). Dr Globus says such a goal is achievable, after perhaps building a colony in Earth orbit

But what would that first space settlement look like? Many designs rely upon a central cylinder around which is a rotating habitat.

In the rotating section the force of rotation provides artificial gravity for the inhabitants, letting the move around like they would on Earth.

‘That means your children will grow up with strong muscles,’ explains Dr Globus, so even if they spend a prolonged time in space they could still travel to Earth and cope with its gravity.

At the centre of the structure though there would be zero-gravity, as there would be no rotation here.

This, explains Dr Globus, could be used for recreation or even to film movies.

Elsewhere on the station would be agriculture, while the outer hull would need to be partially covered in solar cells.

But what would that first space settlement look like? Many designs rely upon a central cylinder around which is a rotating habitat (artist's illustration shown). In the rotating section the force of rotation provides artificial gravity for the inhabitants, letting the move around like they would on Earth

But Dr Globus admits that such an undertaking is something that just isn’t financially feasible - for now.

THE CHALLENGES OF BUILDING A SPACE SETTLEMENT According to Dr Globus there are a number of obstacles that must be overcome before humans can live in space. The first is that the cost of getting to space via rockets must decrease. Next is life support; a future space colony will need to be almost self-sufficient, using indoor farms and solar energy. A colony will also need radiation shielding to protect it from harmful cosmic and solar rays, although recent research says this may not be a big issue. Advertisement

‘If you have to ask [how much it would cost], you can’t afford it,’ he jokes.

He adds: ‘There is one circumstance we could easily afford it, and that’s if the people of Earth decided to stop killing each other and spend all that time and money on space settlements.’

However starting to build a space settlement now is not a good idea, he says, as technology and infrastructure are not yet sufficient.

He says we need to progress through several hoops before settling in space can become a viable option.

One of these is space tourism. Several private companies such as Boeing and SpaceX are busy building manned spacecraft, while others like Bigelow Aerospace are planning to build ‘space hotels’ in orbit.

These orbiting habitats, while much smaller than the large space settlements envisaged by Dr Globus, would allow people to pay for trips to space.

Dr Globus even says these could be used to raise money by hosting what he calls a ‘Space Olympics’ in orbit.

By sending the world’s top athletes to space and having the compete, people would tune in to watch them compete in a variety of micro-gravity sports.

‘You could get Usain Bolt, a soccer star, a basketball star and so on,’ he says.

‘It would be a level playing field because no one knows how to do sports in microgravity. So that would totally be entertaining.’

Dr Globus says we need to progress through several hoops before settling in space can really be a viable option. One of these is space tourism. Several private companies such as Boeing and SpaceX are busy building manned spacecraft, while others like Bigelow Aerospace are planning to build ‘space hotels’ (concepts shown)

The timeline for all this is of course up for debate, but Dr Globus is confident it will happen sooner or later.

‘In two or three decades we might have a couple of small hotels [in orbit], and people moving in on a regular basis,’ he says.

‘Then at some point somebody will notice if you are old and infirm you might like to live on a space hotel, because you wouldn’t be subjected to a 1G hotel and you wouldn’t need a walker or wheelchair.

‘I can foresee someone building a retirement home in low gravity; after a couple of years you won’t be able to come back, but if you’re facing 15 years of sitting in a wheelchair you might not want to do that anyway.

‘And once that step is done, people living in space permanently, then it’s not a big step to build a space settlement in orbit.

‘All that is on a time scale measured in decades, or in the worst case centuries.’

And living in space doesn’t need to stop there. Once a large, floating colony has been built, Dr Globus explains that other locations in the solar system can be explored.

Perhaps, using asteroids for additional material, a space settlement could be placed around the Martian moons Phobos and Deimos.

Once humans have settled in Earth orbit, Dr Globus says it is not a huge leap to imagine they will want to eventually travel further. This could begin with the solar system in a few millennia and, ultimately, expand further into the Milky Way

‘I can imagine within a few centuries that the first settlement will be co-orbiting an asteroid,’ says Dr Globus.

‘To really settle the solar system will take millennia, maybe longer.’

And once that goal has achieved, Dr Globus says there is not much to stop us expanding into the rest of galaxy.

‘Imagine you have been living on orbital space settlements for 10,000 years,’ he says.

‘In your settlement there might be 100,000 people or even millions.

‘If people decided to go to Alpha Centauri, even thought it may take a century to get there, it doesn’t matter, because you’ve been living in this settlement for thousands of years anyway.