Now that aircraft makers are bringing in more-than-ever amount of plastic content into airplanes, consumers realize plastic is not just the material shopping bags are made out of.

Plastics is also making its way into spacecrafts, scientists said, and not just limited to interior parts. It can be used to arm spacecraft bodies and shield them from radiation, a job that can't be done by metals.

Experiments on the International Space Station have shown that plastics such as polyethylene provide good shielding. Plastics contain lots of hydrogen, which is good at absorbing cosmic rays.

Even if the whole spacecraft is not built from plastic, it could be used to shield key areas such as living quarters.

That's according to a recent BBC report. The article explained why metals wouldn't work:

"With this kind of radiation, you cannot simply shield the craft with heavy metal. It can actually make it worse, because when the cosmic rays hit the metal atoms, they can produce secondary particles."

But the best protecting material appears to be water, the article said.