For 100 years, futurists have dreamed about a device that could take people and goods into space without the use of expensive rockets or spaceships.

The key component of such a space elevator would be an ultra-strong, 36,000-kilometre cable. One end would be anchored to the Earth and the other attached to a counterweight in orbit.

A machine carrying goods or people could climb the cable in order to deliver goods into space, says CBC science columnist Torah Kachur.

She told CBC Radio's The Homestretch that such a space elevator hasn't been built because the necessary materials haven't existed yet.

"What you need is a really strong cable," she said. It would need to be able to withstand the powerful winds of the upper atmosphere as well as its own weight, which would be pretty hefty when added up over 36,000 kilometres.

Chemistry researcher John Badding and his team at Penn State University have invented a material that they think could work.

They compressed carbon into a thread that is just three atoms wide, but has the same structure as diamond, making it ultra-strong. They published a description of it in the journal Nature Materials.

So far, the threads are just a few millimetres long, Kachur says, "kind of short of the 36,000 kilometres they'd need."

That's one reason why Kachur thinks a space elevator is still a long way off.

"But the idea here is this is the starting point that allows us to dream about doing this again."