Curiosity Rover May Have Brought Dozens of Microbes To Mars

bmahersciwriter (2955569) writes "Despite rigorous pre-flight cleaning, swabbing of the Curiosity Rover just prior to liftoff revealed some 377 strains of bacteria. 'In the lab, scientists exposed the microbes to desiccation, UV exposure, cold and pH extremes. Nearly 11% of the 377 strains survived more than one of these severe conditions. Thirty-one per cent of the resistant bacteria did not form tough, protective spore coats; the researchers suspect that they used other biochemical means of protection, such as metabolic changes.' While the risk of contaminating the red planet are unknown, knowing the types of strains that may have survived pre-flight cleaning may help rule out biological 'discoveries' if and when NASA carries out its plans to return a soil sample from Mars."

Comments

What goes around comes around

[mendax]

It has been speculated that life here on Earth came from space. And there has been speculation that this life may have come from Mars thanks to asteroid impacts ejecting material with enough energy to reach escape velocity, some of this material reaching the Earth in its early primordial history. Well, if this is the case, we're returning the favor.

Re:What goes around comes around

[mendax]

It just occurred to me that even if we were to find only bacteria whose ancestor's hitchhiked their way to Mars from Earth on one of our probes, that would be a remarkable find in itself. It would demonstrate that life could have existed on Mars at one time even if we don't find any native Martian bugs.

Re:What goes around comes around

[StripedCow]

Did someone bother to send some food for the bacteria?

They will be eagerly waiting for the first manned mission to Mars...

Policy for Planetary Protection

[Strider-]

JPL actually has a highly detailed document on "Policy for Planetary Protection" that details the standards to which a probe must be sanitized to before being sent on its mission. The level of cleanliness depends on the intended mission and target; orbiters have a lesser standard than landers, for example. The policy also takes into account different parts of the spacecraft; the inside of the box containing the CPU and so forth isn't cleaned to as high of a standard as the wheels, experiments and so forth that are directly exposed to the environment. In the case of the Galileo probe, it was deliberately crashed into Jupiter at the end of mission in order to ensure it would never impact Europa, as it had not been cleaned to that high of a standard. Cassini will face a parallel fate, of crashing into Saturn to prevent a collision with Enceladus and/or Titan.

The key part here is that when you are looking for life (or might be looking for life in the near future) you don't want to discover that the life is found is something that you brought from earth yourself, or was brought by another space probe.