Space exploration has captured the imagination of many engineers and scientists, with many dreaming up wild ideas to extend humanity’s reach beyond Earth.

While some of these ideas are straight out of science fiction, certain ones stand a decent chance of working.

Many of these ideas are being worked on, with scientists constructing prototype spacecraft and designing possible solutions to the problems with each idea.

The best ideas are arguably the ones focused on decreasing the cost of launching payloads to space, as this would allow for faster development of space-based structures.

Check out the ambitious space projects being worked on right now, below.

Martian colony

The colonisation of Mars is near the top for many explorers.

Colonisation of the red planet is possible, but it is extremely challenging due to the high cost of launching cargo to the planet, long travel times, and communication delays.

However, pioneers like Elon Musk are working to bring humanity closer to this goal.

NASA is also attempting to solve the problem of sustaining human life on Mars and is considering the viability of 3D-printed habitats constructed ahead of humans landing on the surface.

Additionally, recent evidence of an underground lake beneath the Martian icecaps improves the outlook for colonisation of the planet.

Space elevator

The concept of a space elevator seems insane, but it could be possible.

A space elevator comprises a large cable which stretches from Earth into space.

At the end of the cable is a counterweight which provides it with centrifugal force.

This counterweight would be situated at or above geosynchronous orbit, and would keep the cable taut.

An elevator could then be run up the cable to space, ferrying cargo and passengers cheaply into orbit.

There are currently no materials which can handle the stress of swinging a counterweight around at the speed of the Earth’s rotation, however.

Lunar mass driver

The concept of a lunar mass driver is popular in science fiction, but would also be useful in the real world.

This mass driver would function as an electromagnetic catapult built into the surface of the Moon.

The device would be extremely long and would use electromagnetic acceleration to rapidly accelerate payloads down a tube, ejecting them at orbital velocity and allowing them to fly straight into orbit around the Moon.

A fixed mass driver on the Moon would be possible thanks to the lack of atmosphere and lower gravity on the lunar surface.

Space Catapult

A space catapult is similar to a mass driver, although this project is based on Earth.

Silicon Vally-based startup SpinLaunch has designed a machine which it says can hurl rockets into space from the ground.

The catapult will spin in a circle at up to 5,000 miles per hour and then release its payload, ideally throwing it to the edge of space – at which point the payload may travel into orbit on its own propulsion.

The challenge of hurling payloads through Earth’s atmosphere is unique, as the faster the object travels the more resistance it encounters.

Lightcraft

One of the biggest problems with spacecraft is that they need to supply their own propellant, increasing their weight and requiring more powerful engines.

Researchers have tried to solve this problem by designing “lightcraft”, lightweight spacecraft which are driven by beam-powered propulsion.

One of the most promising designs for this type of spacecraft is the maser-powered propulsion variant, which is driven by a ground-based microwave beam targeted at a reflective panel on its stern.

This is reflected within the panel and ignites onboard gas to produce explosive thrust and move the spacecraft.

The idea has been tested multiple times, but has not been applied to a live spaceflight.

Now read: Scientists discover underground lake on Mars