The stereotypical image of the bald-headed alien visitor to earth may not be as far-fetched as once thought, with new research
suggesting that it simply isn’t possible to grow hair in outer space.
What the scientists say
Japanese researchers have found that the genes responsible for hair growth behave differently in space and that growth inhibitors become more active. This means that hair stops growing, regardless of where it is in its normal growth cycle. The genes identified included FGF18, ANGPTL7, and COMP and their activity led to reduced proliferation in hair follicles, meaning less hair would grow.
The researchers, led by Dr Masahiro Terada, from the Japanese Aerospace Exploration Agency, analysed hair extracted from ten astronauts at different stages of their period of space travel, so that the various stages of hair growth could be examined, both in space (240 miles above the earth’s atmosphere) as well as prior to departure and after their return to earth.
A gender gap
However, they also found that this genetic alteration was less likely to occur in the hair follicles of female astronauts, even after allowing for the difference in hormone levels between the genders. Women just have more genetically stable hair.
Humans in space
The study concludes that it is highly likely that, should humans ever find a way to exist in space for long periods of time, they will become a bald species – much like the alien that we are so familiar with, thanks to popular culture’s representations over the past sixty years.
For astronauts providing maintenance on, for example, the International Space Station, once all their existing hair naturally sheds, an absence of new hair to replace it will leave them bald
. Whether a return to the earth’s atmosphere will also result in a return to normal genetic behaviour and subsequent hair growth
remains to be clarified.