Carbyne

The super-strong carbyne was produced inside double-walled graphene nanotubes to keep it stable. Lei Shi / University of Vienna

Carbyne, a carbon-based structure, has been a theoretical material since it was proposed back in 1885 with scientists only being able to produce it in either computer simulations or very short forms of only 100-atoms long due to its instability. Now thanks to a new production method involving rolling up two sheets of graphene to form a protective tube they then created the carbyne within to stop it from breaking and as a result have managed to synthesise a chain of 6,400 atoms long, which remained stable. - International Business Times

Okay then, that space elevator thingy might just be possible. Now it's just a matter of being able to produce mass quantities of the stuff.

How big is that stick of 6,400 atoms? A carbon atom is about 140 picometers in diameter. A picometer is one-trillionth of a meter.  6,400 times 140 is almost 900,000. Call it a million. So if those 6,400 carbon atoms are stuck together in a line that rod would be almost 1 micron long. Whopee! You might be able to see it under a microscope. The atoms are almost certainly not arranged single file, which means this rod is only a fraction of a micron long. Probably wouldn't be able to see it using a conventional microscope.

So far it's only a claim, we'll have to wait and see if anyone else can do it, and if it is in fact Linear acetylenic carbon. The stuff has been made before, but several times people thought they had made this stuff and it turned out to be something else, like fullerene. How would you even know? I would like to see how it was done, except, there probably isn't anything to see. Strange people waving their hands and chanting with strange equipment. Probably looks a lot like alchemy.