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Signs of Liquid Water Found on Surface of Mars, Study Says

nytimes.com

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Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#31

Post by lmkg »

gambiting wrote: post #15
crusso wrote: post #12

R.S.L.s are treated as special regions that NASA’s current robotic explorers are barred from because the rovers were not thoroughly sterilized We're not going to sterilize our research equipment going to Mars and we're not going to search likely sites where we could find life because we don't want to contaminate them. And yet, looking for signs of life native to Mars (or even water which might support life) is the to…

The article mentions how equipment that needs to be sterilized is baked to a very high temperature - but I wonder, can it not be sterilized with radiation, like we already do with food? All electronics on a rover are already radiation hardened, after all Curiosity has to work while having a chunk of plutonium strapped to its back. Is this not an option of some reason?

Shot in the dark: Killing organisms is not sufficient. The corpse of a bacterium is still a contaminant: It still has organic compounds that can be measured by our equipment, and potentially interact with organic compounds on Mars. For our purposes, the bacterial corpses must be fully incinerated.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#32

Post by [deleted] »

gambiting wrote: post #15
crusso wrote: post #12

R.S.L.s are treated as special regions that NASA’s current robotic explorers are barred from because the rovers were not thoroughly sterilized We're not going to sterilize our research equipment going to Mars and we're not going to search likely sites where we could find life because we don't want to contaminate them. And yet, looking for signs of life native to Mars (or even water which might support life) is the to…

The article mentions how equipment that needs to be sterilized is baked to a very high temperature - but I wonder, can it not be sterilized with radiation, like we already do with food? All electronics on a rover are already radiation hardened, after all Curiosity has to work while having a chunk of plutonium strapped to its back. Is this not an option of some reason?

[deleted]

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#33

Post by eddd »

I know that without water life would have never begun, but I still don't fully understand why it is necessary. It is still big discovery though, if life is that common I think we should be more careful during migration there, "Marsian" common cold could wipe out the entire human colony.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#34

Post by goatforce5 »

crusso wrote: post #12

R.S.L.s are treated as special regions that NASA’s current robotic explorers are barred from because the rovers were not thoroughly sterilized We're not going to sterilize our research equipment going to Mars and we're not going to search likely sites where we could find life because we don't want to contaminate them. And yet, looking for signs of life native to Mars (or even water which might support life) is the to…

> Seems like someone in NASA needs to work out this conflict.

Perhaps it's not so much of a conflict as a multi-staged approach...

The non-sterile equipment is currently roaming around and has just said "Hey! There's probably water and maybe life over there!" and now we get to build something to go poke at it with a sterilized stick.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#37

Post by ForHackernews »

nsxwolf wrote: post #18

Latest incarnation of the perennial headline... Best evidence yet of water on Mars! I've been enjoying these all my life. This and "Nuclear fusion created in a laboratory for the first time" headlines. My favorite best-evidence-yet-of-water-on-Mars was that time the Phoenix robot scooped up an ice cube and took a picture of it.

This finding is about contemporary, liquid, water.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#38

Post by peter303 »

charleywolters wrote: post #36

I mean that's great news but didn't they announce this like 10 times before? Isn't there a meme about this, that NASA announced they found water on Mars like once a year?

Soem of the times were for ancient water. But they have shown evidence of recent water before too.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#39

Post by fudged71 »

barkingcat wrote: post #6
aidos wrote: post #4

I'm so confused. "Definitive signs"? Is this the Nasa announcement or something else? I thought it didn't start for another 15 minutes.

This is most likely the Nasa announcement. Remember folks! Science doesn't happen in a vacuum. The scientific papers that outline this analysis was already available in astronomy circles - the Nasa event is the press conference letting the bigger community know. It's not like it's a secret! All the measurements were already made by the Orbitor and is presumably analysed by researchers around the world prior to this u…

"Science doesn't happen in a vacuum."

This is NASA we're talking about, right? ;)

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#40

Post by gus_massa »

gee_totes wrote: post #19
gambiting wrote: post #15

Earlier quoted context omitted.

The article mentions how equipment that needs to be sterilized is baked to a very high temperature - but I wonder, can it not be sterilized with radiation, like we already do with food? All electronics on a rover are already radiation hardened, after all Curiosity has to work while having a chunk of plutonium strapped to its back. Is this not an option of some reason?

What happens when Curiosity contaminates the RSLs with radiation?

There are many types of radiations:

---

For sterilization, they will probably use gamma rays. They are strong enough to break a lot of chemical molecules, and then kill all the bacteria. But the gamma rays are not strong enough to break the atoms nuclei or make them radioactive. So the rover will be sterilized but not radioactive.

This is similar to the process that irradiate food with gamma rays. You can store them in a perfectly sealed place without refrigeration and they a are safe to eat because they don't have bacteria and they don't have radiation. So this is a safe method. More info: https://en.wikipedia.org/wiki/Food_irradiation

---

Another different radiation process is to irradiate it with neutrons. It kills the bacteria but it also may make some nuclei radioactive. (I don't know the necessary doses, so perhaps this may be safe, but I'd be much more careful. Something like this is used to treat cancer. Also, this don't produce a lot of radioactive atoms, and the rover is small, so the radioactive material will be not too much. Anyway, as I said before, I'd be much more careful.)

---

Another possibility is mixing the food (for example a tea) with some radioactive material (for example plutonium). This kill the bacteria but also may kill whoever takes it. If you are very careful with the doses, you may use something like this for medicine applications (for example with radioactive iodine). But I guess that if the dose is low enough not to kill the patient, it will not kill all the bacteria. This is definitively not the method they may use to sterilize a rover.

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