Scientist: NASA found life on Mars - and killed it

[GrnMarvl14]

Original source.

WASHINGTON (AP) -- Two NASA space probes that visited Mars 30 years ago may have found alien microbes on the Red Planet and inadvertently killed them, a scientist is theorizing.

The Viking space probes of 1976-77 were looking for the wrong kind of life, so they didn't recognize it, a geology professor at Washington State University said.

Dirk Schulze-Makuch presented his theory in a paper delivered at a meeting of the American Astronomical Society in Seattle, Washington.

The paper was released Sunday.

Based on a more expansive view of where life can take root, the paper's findings may prompt NASA to look for a different type of Martian life when its next spacecraft to visit Mars is launched later this year, one of the space agency's top scientists said.

Last month, scientists excitedly reported that new photographs of Mars showed geologic changes that suggest water occasionally flows there -- the most tantalizing sign that Mars is hospitable to life.

In the 1970s, the Viking mission found no signs of life.

But it was looking for Earth-like life, in which salt water is the internal liquid of living cells.

Given the cold dry conditions of Mars, life could have evolved on Mars with the key internal fluid consisting of a mix of water and hydrogen peroxide, said Schulze-Makuch.

That's because a water-hydrogen peroxide mix stays liquid at very low temperatures, or -68 degrees Fahrenheit, and doesn't destroy cells when it freezes. It can suck water vapor out of the air.

The Viking experiments of the 1970s wouldn't have noticed hydrogen peroxide-based life and, in fact, would have killed it by drowning and overheating the microbes, said Schulze-Makuch.

One Viking experiment seeking life on Mars poured water on soil. That would have essentially drowned hydrogen peroxide-based life, he said. And different experiment heated the soil to see if something would happen which would have baked Martian microbes.

"The problem was that they didn't have any clue about the environment on Mars at that time," Schulze-Makuch said. "This kind of adaptation makes sense from a biochemical viewpoint."

Even Earth has something somewhat related. He points to an Earth bug called the bombardier beetle that produces a boiling-hot spray that is 25 percent hydrogen peroxide as a defense weapon.

Schulze-Makuch acknowledges he can't prove that Martian microbes exist, but given the Martian environment and how evolution works, "it makes sense."

In recent years, scientists have found life on Earth in conditions that were once thought too harsh, such as an ultra-acidic river in Spain and ice-covered lakes in Antarctica.

Schulze-Makuch's research coincides with work being completed by a National Research Council panel nicknamed the "weird life" committee. The group worries that scientists may be too Earth-centric when looking for extraterrestrial life.

The problem for scientists is that "you only find what you're looking for," said Penn State University geosciences professor Katherine Freeman, a reviewer of the NRC work.

A new NASA Mars mission called Phoenix is set for launch this summer, and one of the scientists involved said he is eager to test the new theory about life on Mars.

However, scientists must come up with a way to do that using the mission's existing scientific instruments, said NASA astrobiologist and Phoenix co-investigator Chris McKay.

He said the Washington State scientist's paper piqued his interest.

"Logical consistency is nice, but it's not enough anymore," McKay said.

Other experts said the new concept is plausible, but more work is needed before they are convinced.

"I'm open to the possibility that it could be the case," said astrobiologist Mitch Sogin of the Marine Biological Lab in Woods Hole, Massachusetts.

A member of the National Research Council committee, Sogin also cautioned against "just-so stories about what is possible."

Great. We MAY have found life, only to eradicate it. Nice to see they're re-thinking the idea of life, though. Expanding our chances of actually FINDING life.

 

[The Big Al]

It might also expand places where we might find life. Many have theorized life could exist on Titan, Saturn's largest moon and if life like what is suggested exists Titan would be a garden spot. Europa's chances of harboring life might have also improved.

 

[the gadfly]

Great. We MAY have found life, only to eradicate it.

Even if it's true Viking may have killed whatever life existed in the samples they scooped up, I really don't think we made life extinct on Mars. Not even at Viking's landing sites.

EDIT: Here's an intriguing idea: How sterile do you think the probes we've sent to Mars' surface are? Could we be seeding Mars with bacteria from Earth?

 

[GrnMarvl14]

Even if it's true Viking may have killed whatever life existed in the samples they scooped up, I really don't think we made life extinct on Mars. Not even at Viking's landing sites.

HORRIFIC joke on my part.

EDIT: Here's an intriguing idea: How sterile do you think the probes we've sent to Mars' surface are? Could we be seeding Mars with bacteria from Earth?

Can bacteria survive the vacuum of space or the heat of planetary entry? I mean, the rovers were sealed up, but I doubt they were sealed as tight as a space shuttle might be (THERE'S where your bacteria's definitely going to come from).

 

[Barb]

I'm not sure about Titan. I'm currently reading "Back to the Astronomy Café" by Sten Odenwald. He describes the surface of Titan as having a temperature of -290 degrees F. The atmosphere has been spectroscopically studied and contains nitrogen, methane, hydrogen, propane, acetylene, ethylene, hydrogen cyanide, and cyanoacetylene.

Then again, there are some pretty odd factories here on Earth for cooking up organic molecules under almost impossible conditions (like the extremophiles living in the deepsea vents, or near the geysers and hot springs of Yellowstone).

 

[the gadfly]

Can bacteria survive the vacuum of space or the heat of planetary entry? I mean, the rovers were sealed up, but I doubt they were sealed as tight as a space shuttle might be (THERE'S where your bacteria's definitely going to come from).

Spores, think spores.

Many bacteria go into a spore stage to get through poor environmental conditions. They're sealed up in their cases. Vacuum means nothing to them. The heat of planetary entry would kill anything on the outer surfaces, but if the lander survives, so will any bacterial spores inside it or on its surface.

Spores from thousands of years ago have been revived as soon as they were put into a friendly environment.

It's true Mars isn't as friendly to life as Earth is, but we know there are life-forms on Earth that could survive in the Martian environment.

Besides, how sterile could we make spacecraft? We could bake them in heat or irradiate them. We could spray them with antiseptics. We could do lots of things to sterilize anything we send to another body's surface, but we risk damaging the lander. And whatever we do, we'd have to do it to the point the spacecraft leaves Earth's atmosphere because, after all, we do live on a plant where the total mass of bacteria far outweighs that of everything else living.

 

[Zhen Lin]

The one where they are most concerned about bringing Earth bacteria to is Europa.

Indeed, they'll probably have to launch and sterilise the probe out in space. Hmm, there's an idea for how to use the ISS.

 

[FabuVinny]

Wow... why am I seeing such striking similarites emerging with human expansion on Earth? (I'm thinking the Age of Empires here.)

 

[GrnMarvl14]

Spores, think spores.

Many bacteria go into a spore stage to get through poor environmental conditions. They're sealed up in their cases. Vacuum means nothing to them. The heat of planetary entry would kill anything on the outer surfaces, but if the lander survives, so will any bacterial spores inside it or on its surface.

Spores from thousands of years ago have been revived as soon as they were put into a friendly environment..

I always hated cellular biology. And, as such, I always seem to forget about it. In this case, it wasn't until you said something that spores entered my mind. And that does make sense that they could survive the journey in that state.

Besides, how sterile could we make spacecraft? We could bake them in heat or irradiate them. We could spray them with antiseptics. We could do lots of things to sterilize anything we send to another body's surface, but we risk damaging the lander. And whatever we do, we'd have to do it to the point the spacecraft leaves Earth's atmosphere because, after all, we do live on a plant where the total mass of bacteria far outweighs that of everything else living.

There's one thing I stupidly forgot. They built the rovers in a clean room. Germ free. So, at the very least, they should be somewhat clean. Though I'm unsure of where the landing craft are constructed and how the whole take-off and arrival thing works. While I've no doubt that the original Viking landers probably brought some uninvited guests, they're at least thinking of such things now...if they haven't before.

Would be interesting if they found life on Mars and it was some simple, one-celled, common Earthly organism. Wonder how that would be received, and if they'd ask themselves if they had contaminated things.

 

[the gadfly]

There's one thing I stupidly forgot. They built the rovers in a clean room. Germ free. So, at the very least, they should be somewhat clean.

Not exactly. Though it is true landers are assembled in a clean room--the individual components may have been assembled in less pristine conditions. All that matters is that they perform according to specification when shipped--"clean room" means there isn't any dust or gross contaminants floating around. The landers themselves are still assembled by hand by humans. There's no way you can make humans germ free without killing them.

(No, the assemblers don't wear isolation suits. There have been plenty of photographs of people assembling spacecraft. They wear disposable garments and hats or hair bonnets. Those with facial hair wear masks. None wear gloves.)

Having said that. there is a decontamination phase following assembly. I'm not sure, but I think it's done by exposing the spacecraft to ultraviolet light for many hours.

Then, the spacecraft sits around for days, weeks, months, sometimes years, until it's launched. Somehow, I doubt it'll remain sterile that long.

Let's not forget it needs to be transported to the launch site, placed on the rocket, and have its communication and electrical cables connected so everything needed to send the craft on its way will happen. Lots of oppotunities there for bacterial contamination.

Would be interesting if they found life on Mars and it was some simple, one-celled, common Earthly organism. Wonder how that would be received, and if they'd ask themselves if they had contaminated things.

That's a very interesting question. Honestly, I don't think it matters. Once humans land on Mars, all the germs they brought with them will become Martians. Then it becomes a question of survival of the fittest--Earth vs. Mars.

 

[inkysquid12]

Even if it's true Viking may have killed whatever life existed in the samples they scooped up, I really don't think we made life extinct on Mars. Not even at Viking's landing sites.

EDIT: Here's an intriguing idea: How sterile do you think the probes we've sent to Mars' surface are? Could we be seeding Mars with bacteria from Earth?

I'm not sure about mars but bacteria from earth survived for 3 years on the moon. It's probably quite likely that this kind of bacteria would be able to survive on Mars. If we have failed to completely sterilise landing probes before, it could have happened since, or could do so in the future.

"The streptococcus bacteria on Surveyor 3 might not be the only interplanetary microbial hitchhikers. In 1996, researchers at NASA's Johnson Space Center announced that they had found evidence of microfossils in a Mars meteorite recovered from a field of blue ice in the Antarctic."

Full link here:

http://science.nasa.gov/newhome/headlines/ast01sep98_1.htm

 

[inkysquid12]

I'm not sure about Titan. I'm currently reading "Back to the Astronomy Café" by Sten Odenwald. He describes the surface of Titan as having a temperature of -290 degrees F. The atmosphere has been spectroscopically studied and contains nitrogen, methane, hydrogen, propane, acetylene, ethylene, hydrogen cyanide, and cyanoacetylene.

Then again, there are some pretty odd factories here on Earth for cooking up organic molecules under almost impossible conditions (like the extremophiles living in the deepsea vents, or near the geysers and hot springs of Yellowstone).

The theory is that any life on Titan would be found in oceans, deep under the surface. There may be liquid water oceans because obviously the planet gets hotter nearer the core, probably hot enough for liquid water to form. I'm not sure of the implications of the atmospheric pressures on an environment so close to the core (especially because there is so little energy at the edge of the solar system, the core is probably significantly cooler than that of Earth's). It's a long shot but as you say, extremophiles have proved that life can often find a way. Europa is still a better bet though as it almost certainly has liquid oceans under the surface.

 

[the gadfly]

"The streptococcus bacteria on Surveyor 3 might not be the only interplanetary microbial hitchhikers. In 1996, researchers at NASA's Johnson Space Center announced that they had found evidence of microfossils in a Mars meteorite recovered from a field of blue ice in the Antarctic."

No need to drag in the controversy about whether that Martian meteorite showed evidence of life on Mars sometime in the past.

The more important news is that viable streptococci were found on Surveyor 3. Mars is far more habitable to life than the moon.

 

[inkysquid12]

Yeah i just put in the only bit about Mars i saw so it looked more superficially relevent to your post. Mainly posted due to the relevence of streptococci.

 

[Johtoman 2]

Brilliant! I knew there was life! Oh well, now they've killed it they won't have to worry about alien invasion from Mars.
P.S. I know someone who's last name is Freeman...

 

[the gadfly]

Huh?

What did you smoke or drink before making that post?