It sounds like science fiction – a factory, located hundreds of kilometres above the Earth, churning out high-quality materials.

But a Cardiff-based company is a step closer to making this a reality.

Space Forge have sent a microwave-sized factory into orbit, and have demonstrated that its furnace can be switched on and reach temperatures of around 1,000C.

They plan to manufacture material for semiconductors, which can be used back on Earth in electronics in communications infrastructure, computing and transport.

Conditions in space are ideal for making semiconductors, which have the atoms they’re made of arranged in a highly ordered 3D structure.

When they are being manufactured in a weightless environment, those atoms line up absolutely perfectly. The vacuum of space also means that contaminants can’t sneak in.

The purer and more ordered a semiconductor is, the better it works.

“The work that we’re doing now is allowing us to create semiconductors up to 4,000 times purer in space than we can currently make here today,” says Josh Western, CEO of Space Forge.

“This sort of semiconductor would go on to be in the 5G tower in which you get your mobile phone signal, it’s going to be in the car charger you plug an EV into, it’s going to be in the latest planes.”

The company’s mini-factory launched on a SpaceX rocket in the summer. Since then the team has been testing its systems from their mission control in Cardiff.

Veronica Viera, the company’s payload operations lead, shows us an image that the satellite beamed back from space.

It’s taken from the inside of the furnace, and shows plasma – gas heated to about 1,000C – glowing brightly.

She told us seeing the image was “one of the most exciting moments of my life”.

“This is so important because it’s one of the core ingredients that we need for our in-space manufacturing process,” she explains. “So being able to demonstrate this is amazing.”

The team is now planning to build a bigger space factory – one that could make semiconductor material for 10,000 chips.

They also need to test the technology to bring the material back to Earth.

On a future mission, a heat shield named Pridwen after the legendary shield of King Arthur will be deployed to protect the spacecraft from the intense temperatures it will experience as it re-enters the Earth’s atmosphere.

Other companies are also looking skywards – to make everything from pharmaceuticals to artificial tissues.

“In-space manufacturing is something that is happening now,” says Libby Jackson, head of space at the Science Museum.

“It’s the early days and they’re still showing this in small numbers at the moment.

“But by proving the technology it really opens the door for an economically viable product, where things can be made in space and return to Earth and have use and benefit to everybody on Earth. And that’s really exciting.”