Five of the most important International Space Station experiments

It’s not all eating bits of food floating in mid-air and introducing suction toilets to fascinated Earthlings – crews on the International Space Station (ISS), which will be coming to an end soon, have serious work to do.

Since the station’s inception, astronauts and cosmonauts have performed more than 3000 experiments in the microgravity and heightened radiation of low-Earth orbit. These have ranged from confirming that fertility levels remain unaltered (in mice, not crew members) to testing the prospects of using lunar soil to make concrete to help build future moon bases. Here are four more of the most impressive bits of ISS research.

Artificial retinas

For millions of people with degenerative conditions affecting the retina – the layer of light-sensitive cells at the back of the eye – there is no cure, only treatments that slow progression. However, an implant that mimics the function of the retina might be the solution, and US-based company LambdaVision has had some success making one by depositing layer upon layer of a light-activated protein known as bacteriorhodopsin. On Earth, solutions of it tended to clump together, leading to poor deposition, but much better results came early this decade in the microgravity aboard the ISS. LambdaVision is now trying to scale up space manufacturing of the artificial retinas and claims these are among the first technologies evaluated on the ISS that have the potential for clinical use.

Invisible flames

When you light a match, the wood burns, reacting with oxygen to produce heat and light, as well as some other products such as carbon…