A journey to a star would mean a minimum of 20 years in the confinement of a spaceship – not impossible but a physical and mental strain for the crew – would they arrive in the right frame of mind to tackle the rigours of a new environment. Also they would be at least 20 years older, so experienced astronauts in their 30’s would already be ‘old’ on arrival. Maybe our crew would comprise of families with babies who would be young adults at the end of the journey. But this scenario is more likely for colonisation far ahead in the future.
So some form of hibernation, a method of protracted sleep, is almost certainly a must for future travel to our nearest stars. The term that springs to most people’s minds is cryo-hibernation [cryo meaning cold] but let us immediately dismiss the myth that you can freeze the human body and thaw back to life years later. Our bodies are 65% water and when that freezes it expands because ice has a lower density. The damage to sensitive cells and membranes would be traumatic. It’s a great process for preserving meats, fish etc in our freezers but in no way addresses human hibernation.
A cryo process is almost certainly the way forward as we have to slow down dramatically the bodies’ metabolism whilst maintaining a supply of oxygen to every vital organ. A hibernation temperature in the range +10 degrees Celsius to -5 degrees would be required but for the lower temperatures some form of antifreeze would have to be injected into the bloodstream which could cause complications. I consider that +5 degrees Celsius would be optimum to operate a minimal metabolism whilst maintaining tissue integrity.
There are many other issues to consider. When you wake in the morning you often feel stiff and can hardly get your eyes open! How would we cope after 20 years sleep?
I will discuss these issues in future posts and propose the technology and equipment for successful hibernation but if you want to pre-empt this then….
….board my starship in 2150 and sleep for 20 years when you will arrive at the star Seren, 10 light years away, in search of – The Blue People of Cloud Planet.