Science Forums 2

[CraigD]

Originally Posted by alxian

What's your opinion on chidlren being trained as astronauts (being sent up into space very early so they have a greater affinity with microgravity) and doing their studies in space.

Since most adults who aren’t unusually susceptible to motion sickness appear able to adapt to microgravity readily enough, I didn’t initially give alxian’s question much thought. However, after a second reading, a substantial ethical concern, unrelated to the risks of spaceflight, comes to mind. Unfortunately, evidence supporting the claim on which my concern based is sketchy, including an episode of the TV show “Brainiac: Science Abuse” (a British science show know for questionable science, including outright faking of “experiments”).

Under a certain age (this is the sketchy part – sources give this age as anywhere from 2 year to 5, with, to my knowledge, no supporting experimental data), the vestibular systems of children are incompletely developed, making them neurologically incapable of motion sickness, which occurs when the motion detected by one’s vestibular system doesn’t agree with that detected by ones visual and other sensory systems. As these systems develop in a child, after an initial period of effective immunity to motion sickness, she/he tends to experience a period, sometimes many years long, in which her/his susceptibility is greater than it will be in adulthood.

The acquisition of basic perceptual neurological systems tend to be time-critical – for example, cats deprived of their sense of sight (eg: with eyes constantly closed or covered) during a several week period as kittens, are never able to acquire normal visual perception (see “Implications of the Hubel Wiesel experiments for how the blind dream” for more description).

I’m uncertain what the effects of a prolonged absence of normal gravity would have on a child’s neurological development. Possibly, they might never be able to develop the normal sense of balance necessary to do such things as walk upright on a planetary surface.

Ethical organizations, such as space agencies with the capability of placing a child or adult in microgravity for a long period, are unlikely to risk this – and possibly other - potentially devastating, permanent developmental disorders, unless the risk can be justified against a great potential gain in knowledge or for a particular child.

The only child I can imagine who might benefit from long exposure to microgravity would be one suffering from an conventionally incurable condition exacerbated by normal gravity, such as a very weak heart, circulatory system, or musculoskeletal system. Given current manned spaceflight technology, such a child would likely be at unacceptable risk of injury from the high forces experienced when being launched into space.

Wouldn't children get used to being in microgravity faster than adults? Living and working in a 3D environment without a gravity bias?

Possibly. However, such a benefit might require that the child be very young – under two years old. For reasons such as the one I describe above, the risk likely outweighs the potential benefit too greatly for such an experiment to be conducted

Have their been any studies on how quickly/well children adapt to microgravity?

None of which I’m aware.