Earth Bacteria May Hitch A Ride To The Stars

An anonymous reader writes "Space.com has an article on how old rocket stages are carrying bacteria from Earth to interstellar space. For example, four upper rocket stages were used to boost deep space probes Voyager 1, Voyager 2, Pioneer 10 and New Horizons. The spacecraft were sterilized, but the rocket stages were not, and they now carry the bacteria of the engineers who handled them. If the rocket stages hit a habitable planet, and the bacteria survive the journey, they would be able to reproduce and colonize the planet ... not that there's a high liklihood of that. 'In 40,000 years, this wayward 185-pound (84 kilogram) lump of metal will pass by the star AC+79 3888 at a distance of 1.64 light-years. ... Given the sheer expanse of time that lies ahead of the four discarded rockets, at least one is likely to eventually encounter a planet. But even if that planet's environment is conducive to life, the long dormant bacteria will not just gently plop into some exotic ocean. No soft landing can be expected.'"

Justification?

[Anonymous Coward]

Given the sheer expanse of time that lies ahead of the four discarded rockets, at least one is likely to eventually encounter a planet.

I don't see the justification with this statement. Why can't a discarded rocket be locked into a stable orbit around a star instead? Or hit an asteroid? Or go into a star? I think they're being a little too optimistic that one of these fragments is going to land on a planet.

Can bacteria survive the re-entry temperature?

[Ruvim]

If planet is habitable, it got to have the atmosphere. Here is a pretty good chance that the stage will just burn-up on entry. I doubt that any bacteria will survive the temperature at which the metal burns.

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Just four....

[sholden]

More likely for them all to end up in a star/black hole than a planet, or a huge gas giant than a nice habitable planet with water oceans.

It's unlikely to just happen to pass through the "disk" around a star where the planets are at near parallel angle, more likely to come from "above" so to speak and hence unlikely to hit much - of course my understanding of astronomy approaches zero.

Not to mention sterilized by close encounters with a radiation source (like say a star)...

I doubt it

[peterprior]

To quote the late Douglas Adams:

"Space is big. Really big. You just won't believe how vastly hugely mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space."

Re:Justification?

[Ngarrang]

My thought drifted more towards the fact that space is HUGE. The likely hood of impacting ANYTHING but dust is remote.

Re:But...

[BurntNickel]

Being exposed to the near-vacuum of space for an extended period of time, aren't the bacteria likely to be "pulled apart" at the molecular level?

No, contrary to popular opinion, vacuum does not suck

Re:Can bacteria survive the re-entry temperature?

[WindBourne]

In 40K years, we will either be in the same realm or we will be extinct. Either way, it does not matter.

Re:Justification? Sun must hit planet then right?

[markk]

If chances are that these probes will hit a habitable planet are good then the Sun must surely hit a habitable planet as it moves about the galaxy. In fact every Sun must hae a good chance - they are all moving at roughly the same interstellar speed as the stages, they are much bigger so they have a much bigger change of hitting something ... doesn't seem so likely now? the chances of those stages hitting any planet are ... well astronomical in the best sense. Love that line - space is very big.

Re:Don't worry...

[Anonymous Coward]

urine is sterile. I should hope everyone washes their hands after taking a dump.

Beyond the obvious point that very few people urinate directly on their hands, the delivery device is often not sterile. Hand washing afterward is certainly recommended.

Re:Don't worry...

[slofstra]

Ahh! So I should actually be washing my hands in my urine.

Re:Justification?

[Torvaun]

How many numbers are there between 3 and 4?

Now, how many of those numbers are 7?

Infinite possibilities and all possibilities are very different things.