Study
Tardigrades survive exposure to space in low Earth orbit
Jönsson, K. Ingemar; Rabbow, Elke; Schill, Ralph O.; Harms-Ringdahl, Mats; Rettberg, Petra
Current Biology, 2008
Desiccated tardigrades were flown on a satellite and exposed for ten days in low Earth orbit to vacuum alone, or to vacuum plus solar ultraviolet radiation at different wavelength ranges, then returned and rehydrated. Ground controls were held desiccated in the same state.
- Studied in
- Richtersius coronifer, Milnesium tardigradum
- Sample size
- desiccated tardigrades flown in low Earth orbit
Survival of vacuum alone was high, comparable to ground controls. Adding full-spectrum solar ultraviolet radiation reduced survival drastically, with only a small proportion of one species recovering. Some survivors reproduced afterwards.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Anhydrobiotic tardigrades tolerate the vacuum of space, and the limiting factor for survival in orbit is ultraviolet radiation rather than vacuum or cold.
How NatureHQ reads it
This is the paper behind "tardigrades survive in space", and it says something narrower and more interesting. Vacuum turned out to be nearly survivable — which is remarkable, because vacuum boils water out of ordinary tissue, and a tardigrade in the tun state has already removed the water. Unfiltered sunlight was the thing that killed them, and it killed most of them. The animal was also desiccated, not active: an active tardigrade in space would die immediately. "Survived exposure to space" is true of dehydrated animals shielded from ultraviolet, and the qualifiers are the finding rather than fine print.
- Only desiccated animals were tested; the tun state is a precondition, not a detail.
- Ten days in low Earth orbit is not interstellar space, and the radiation environment differs substantially.
- Survival under full solar ultraviolet was very low, which the popular summary omits.
Ten days in orbit, dried out and unshielded
Can an animal survive direct exposure to space?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: Cell PressPublished in a Cell Press journal.
doi.org/10.1016/j.cub.2008.06.048
This reference was resolved automatically against Crossref on 2026-08-11.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-11.