Some animals survive the vacuum
Tardigrades in a dried tun state have survived exposure to open space on a satellite, including vacuum and, with some shielding, solar ultraviolet.
Established2 min read
In the tun state a tardigrade replaces water, curls up, and nearly stops metabolism. The European Space Agency’s FOTON-M3 mission exposed them on the Biopan platform. Vacuum alone was tolerable for many. Full solar UV plus vacuum was lethal to most, but a subset shielded from the worst UV revived and reproduced.
This is not a claim that they enjoy space, or that they evolved for orbit. It is a claim that the physics of extreme drying — disordered proteins, trehalose or tardigrade-specific protectants, DNA repair on waking — is enough to cross a void that kills a wet cell in seconds.
Caveats
- Survival was partial and depended on the UV dose. Vacuum is the kinder half of space.
- Active, hydrated tardigrades do not have this resistance.
Sources
- 1Jönsson K. I. et al.. Tardigrades Survive Exposure to Space in Low Earth Orbit. Current Biology 18, 2008.