Could people one day be cloned in outer space?

It has launched a competition for scientists to create a thick and functional skin tissue that could survive off the planet.

The space agency is studying the health risks and improvements needed to medicine keep space crews healthy during future, longer, space missions.

It was worked with Methuselah Foundation's New Organ Alliance to investigate how to improve bioengineering through a competition called the Vascular Tissue Challenge.

The agency fund to three teams asked to create a "metabolically-functional" human vascularized organ tissue that can be artificially controlled inside a laboratory.

To win, teams have to produce a 1cm-thick tissue that can maintain more than 85 percent survival of its cells over 30 days.

Steve Jurczyk, associate administrator for NASA, said: "The humans who will be our deep space pioneers are our most important resource on the Journey to Mars and beyond."