ESA: Lichen survives in space (temporarily)



This is pretty interesting. I wonder if the lichen communities would survive in deep space though and for how long. What would happen if this got transported (safely) to the martian surface?

A new launch is scheduled for Tuesday July 26th.
http://www.nasa.gov/returntoflight/main/in...tml?skipIntro=1

Let's hope all goes well this time.

Ok, let's examine some of your points.

Time: Can vary. It doesn't always take ejecta millions of years to get there. It can happen within thousands or less depending on the circumstances. Also see the comment about food.

Shielding: The rock can have dense metals or other materials on the surface. Also depends on how deep the microbe is inside. There may also be pockets within to protect against the vaccuum.

Thermal protection: Once again, depends on the makeup of the rock, the amount of time to impact, and other factors. Could make the temps within warmer by maybe a few degrees - not perfect but helps survival.

Food supply: Certain organisms can form a very durable spore (like anthrax for example) when the nutrients aren't at hand. They can even revive after hundreds of thousands of years in such a state ( BBC link )

The only thing the rover seems to have going for it is impact survival - the slow and safe landing of the rover does make it a better mode of transport over the ejecta. But besides that, nothing much.

Anything else?

What's so different about the rovers that make them better at transporting microbes than pieces of ejecta? The organisms might not survive if they were on the surface of the rock, but they have far better chances if they are inside the rock or maybe in frozen water/hydrocarbons. And the "facts" are actually assumptions based on evidence of how life on earth adapts and evolves. Call it more of an educated guess .

And bravo to dvandorn for some excellent points.

That's assuming that earth life will be so prolific as to spread all over the planet. This is quite unlikely even for thousands of years after contamination has occured. If they even survive, the microorganisms would take very long to adapt and spread from one nutrient rich niche to another. And of course theres fact that contamination already occured naturally as stated in the thread by others, which makes the sterilization attempts superfluous (in my opinion at least).

Forgive me if this sounds simple minded, but what is so terrible about bacterial or viral particle contamination on Mars? I never understood how life could be considered as "pollution" on a (as far as we know) lifeless world such as Mars. Isn't one of our main goals to seed and spread life throughout the solar system? As one member mentioned, if we are ever to colonize or terraform any other planet or satellite, then we will obviously introduce other forms of life such as simple microorganisms, certain plants (for food), and possibly insects.

Of course there might be a few negative aspects from this contamination (possible new pathogens, hindrance to our search for native life, etc), but in my view the benefits far outweigh the downsides.