Subscribe to New Scientist magazine

'Water bears' are first animal to survive space vacuum

Movie Camera
  • 17:50 08 September 2008
  • news service
  • Rachel Courtland
Printable versionEmail to a friendRSS FeedSyndicate
Tardigrades, or water bears, are microscopic animals that live in soil and other environments
Water bears, similar to the one pictured here, were sent to low-Earth orbit in an ESA satellite (Courtesy: Ralph Schill)
Water bears, similar to the one pictured here, were sent to low-Earth orbit in an ESA satellite (Courtesy: Ralph Schill)

Tiny invertebrates called 'water bears' can survive in the vacuum of space, a European Space Agency experiment has shown. They are the first animals known to be able to survive the harsh combination of low pressure and intense radiation found in space.

Water bears, also known as tardigrades, are known for their virtual indestructibility on Earth. The creatures can survive intense pressures, huge doses of radiation, and years of being dried out.

To further test their hardiness, Ingemar J�nsson of Sweden's Kristianstad University and colleagues launched two species of dried-up tardigrades from Kazakhstan in September 2007 aboard ESA's FOTON-M3 mission, which carried a variety of experimental payloads.

After 10 days of exposure to space, the satellite returned to Earth. The tardigrades were retrieved and rehydrated to test how they reacted to the airless conditions in space, as well as ultraviolet radiation from the Sun and charged particles from space called cosmic rays.

The vacuum itself seemed to have little effect on the creatures. But ultraviolet radiation, which can damage cellular material and DNA, did take its toll.

Dried out

In one of the two species tested, 68% of specimens that were shielded from higher-energy radiation from the Sun were revived within 30 minutes of being rehydrated. Many of these tardigrades went on to lay eggs that successfully hatched.

But only a handful of animals survived full exposure to the Sun's UV light, which is more than 1000 times stronger in space than on the Earth's surface.

Before this experiment, only lichen and bacteria were known to be able to survive exposure to the combination of vacuum and space radiation.

"No animal has survived open space before," says developmental biologist Bob Goldstein of the University of North Carolina at Chapel Hill, who was not affiliated with the study. "The finding that animals survived rehydration after 10 days in open space � and then produced viable embryos as well � is really remarkable."

This ability to survive in extreme conditions "might be important when we consider the habitability of other bodies in our solar system or beyond," says astrobiologist Gerda Horneck of the German Aerospace Center. But the results say little about how the animals might develop and reproduce in harsh environments, Horneck says.

The authors aren't sure what causes the animals to be as resistant as they are to the effects of ultraviolet radiation. They speculate their hardiness might stem from the same adaptations that enable tardigrades to bounce back from being dried out.

Journal reference: Current Biology (vol 18, p R1)

Astrobiology � Learn more in our out-of-this-world special report.

Comment subject
No HTML except lower case italic tags or lower case bold tags, please:
<i> or <b>
Your name
Your email

We need your email in case we need to contact you about the comment. We will not use it for any other purpose.

There are 12 comments on 2 pages
1  | 
 | Next
 | Most Recent
 | See all

By Jd

Mon Sep 08 19:15:06 BST 2008

So why isn't there a comic book hero with the proportional strength and durability of a tardigrade? These eight-legged wonders put that arachnid-themed hero to shame.


Alien Rising

By Diegoth

Mon Sep 08 19:24:32 BST 2008

Now I know how the Aliens evolved!

Those scientists must keep out of Lt. Ellen Ripley...


Aw Isnt It Cute

By Carebear

Mon Sep 08 20:14:54 BST 2008

I think there awesome, I reckon we should send them off to mars and let them have there own little empire.

There bound to love mars, dont know what they would eat. Martion Tardigrades?

Be like war of the worlds all over again but on a really small scale


Aw Isnt It Cute

By Gordon Barr

Wed Sep 10 01:17:48 BST 2008

Your grasp of english usage and spelling is atrocious


There are 12 comments on 2 pages
1  | 
 | Next
 | Most Recent
 | See all

All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.

If you are having a technical problem posting a comment, please contact technical support.

Printable versionEmail to a friendRSS FeedSyndicate
Cover of latest issue of New Scientist magazine
  • For exclusive news and expert analysis every week subscribe to New Scientist Print Edition
  • For what's in New Scientist magazine this week see contents
  • Search all stories
  • Contact us about this story
  • Sign up for our free newsletter
Subscribe to New Scientist magazine