If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Bad Astronomy and Universe Today Forum > Space and Astronomy > Life in Space
Register FAQ Members List Calendar Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
  #1 (permalink)  
Old 29-February-2008, 03:14 PM
ToSeek's Avatar
ToSeek ToSeek is online now
Vulcan Moderator
 
Join Date: Oct 2001
Location: Greenbelt, MD
Posts: 23,998
Default Natural processes seem to favor amino acid "handedness"

ASU researcher may have discovered key to life before its origin on Earth

Quote:
An important discovery has been made with respect to the mystery of “handedness” in biomolecules. Researchers led by Sandra Pizzarello, a research professor at Arizona State University, found that some of the possible abiotic precursors to the origin of life on Earth have been shown to carry “handedness” in a larger number than previously thought.
...
“Thanks to the pristine nature of this meteorite, we were able to demonstrate that other extraterrestrial amino acids carry the left-handed excesses in meteorites and, above all, that these excesses appear to signify that their precursor molecules, the aldehydes, also carried such excesses,” Pizzarello said. “In other words, a molecular trait that defines life seems to have broader distribution as well as a long cosmic lineage.”
__________________
Everything I need to know I learned through Googling.
Reply With Quote
  #2 (permalink)  
Old 29-February-2008, 04:05 PM
eburacum45's Avatar
eburacum45 eburacum45 is offline
Senior Member
 
Join Date: Jun 2003
Location: old york
Posts: 4,428
Default

But they don't know what causes this bias. I wonder what it could be...

Two theories I have heard;
Polarisation of light in interstellar space or elsewhere causes certain molecules to be favoured in certain regions; perhaps if the universe as a whole were considered the bias would even itself out.
Or
A bias in the very make up of our universe- in particular the parity violation in certain interactions
http://en.wikipedia.org/wiki/Parity_...rity_violation
Somehow, but I don't know if anyone knows quite how, this might bias the handedness of biological molecules all over the universe.
Reply With Quote
  #3 (permalink)  
Old 29-February-2008, 07:30 PM
Noclevername's Avatar
Noclevername Noclevername is offline
Senior Member
 
Join Date: Apr 2007
Posts: 10,606
Default

I'd like to know more about the "pristine nature" of this meteor. It's been sitting around for all these years, what kept it so minty fresh?
__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort
Reply With Quote
  #4 (permalink)  
Old 01-March-2008, 02:54 AM
DrWho DrWho is offline
Member
 
Join Date: Jan 2008
Posts: 90
Default

Quote:
Originally Posted by Noclevername
I'd like to know more about the "pristine nature" of this meteor. It's been sitting around for all these years, what kept it so minty fresh?
Perhaps it's the internals of the meteorite that remained pristine/uncontaminated.
Reply With Quote
  #5 (permalink)  
Old 01-March-2008, 03:11 AM
Ronald Brak Ronald Brak is offline
Senior Member
 
Join Date: Jun 2006
Posts: 4,967
Default

Pristine? Some of those meteorites landed in manure. Claims were made in 2000 that extraterrestrial life had been found in them. Strangely enough exactly the sort of life you find on a rock if you throw in the middle of a farmyard.
Reply With Quote
  #6 (permalink)  
Old 01-March-2008, 08:24 PM
Ara Pacis's Avatar
Ara Pacis Ara Pacis is offline
Senior Member
 
Join Date: Aug 2005
Location: between the candle and the star.
Posts: 1,890
Default

Cool, so does this mean aliens will also be mostly right-handed?
__________________
"What you think you thought you saw you did not see." Agent J, MiB - Manhatten Bureau
Reply With Quote
  #7 (permalink)  
Old 03-March-2008, 07:25 PM
A.DIM's Avatar
A.DIM A.DIM is offline
Senior Member
 
Join Date: Nov 2002
Location: Kentucky
Posts: 3,346
Default

Excellent.

"In other words, a molecular trait that defines life seems to have broader distribution as well as a long cosmic lineage."

Might as well have said "cosmic ancestry," but could this be considered supportive of panspermia?
__________________
"Where the telescope ends, the microscope begins. Which of the two has the greater view?" - Hugo

"Men occasionally stumble over the truth, but most pick themselves up and hurry off as if nothing had happened." - Churchill
Reply With Quote
  #8 (permalink)  
Old 03-March-2008, 09:08 PM
transreality's Avatar
transreality transreality is offline
Senior Member
 
Join Date: Jun 2006
Posts: 416
Default

so the CA was a cacky-hander (sorry to all other LHers for the crude reference). Anyway, a bias in the orientation of precursor organic molecules, hardly constitues the transmission of biological information of such complexity that it supplants evolution as CA claims, now does it, or is this what you have been reduced to claiming, since all else has been debunked. A hydrogen atom can have a long 'cosmic lineage' omg..ca!
__________________
plenty of woo, at the hotel hoagaland...
Reply With Quote
  #9 (permalink)  
Old 03-March-2008, 09:34 PM
A.DIM's Avatar
A.DIM A.DIM is offline
Senior Member
 
Join Date: Nov 2002
Location: Kentucky
Posts: 3,346
Default

I've not made any claims nor am I aware "all else has been debunked" which regards strong panspermia, or as you say, the cacky-hander CA.

Whatever the case, this simply appears to reinforce the notion that physics and chemistry are everywhere the same, which, IMO, supports panspermia.
__________________
"Where the telescope ends, the microscope begins. Which of the two has the greater view?" - Hugo

"Men occasionally stumble over the truth, but most pick themselves up and hurry off as if nothing had happened." - Churchill
Reply With Quote
  #10 (permalink)  
Old 04-March-2008, 01:38 AM
Noclevername's Avatar
Noclevername Noclevername is offline
Senior Member
 
Join Date: Apr 2007
Posts: 10,606
Default

Quote:
Originally Posted by A.DIM View Post
Might as well have said "cosmic ancestry," but could this be considered supportive of panspermia?
No, just a confirmation that the materials of life are common. We already knew that the molecular precursors of life were common, this is just another refinement of that. Still just raw materials, nothing about panspermia, or actual extraterrestrial life.
__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort
Reply With Quote
  #11 (permalink)  
Old 04-March-2008, 08:02 AM
agingjb's Avatar
agingjb agingjb is offline
Senior Member
 
Join Date: Feb 2005
Location: UK
Posts: 365
Default

I'm sure carbon chemistry is universal, but it's so astonishly diverse that I wonder if we would characterise most of its complex manifestations as "life".
Reply With Quote
  #12 (permalink)  
Old 04-March-2008, 08:14 AM
Noclevername's Avatar
Noclevername Noclevername is offline
Senior Member
 
Join Date: Apr 2007
Posts: 10,606
Default

Quote:
Originally Posted by agingjb View Post
I'm sure carbon chemistry is universal, but it's so astonishly diverse that I wonder if we would characterise most of its complex manifestations as "life".
I am, are you?
__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort
Reply With Quote
  #13 (permalink)  
Old 04-March-2008, 07:51 PM
Ara Pacis's Avatar
Ara Pacis Ara Pacis is offline
Senior Member
 
Join Date: Aug 2005
Location: between the candle and the star.
Posts: 1,890
Default

Would the chemicals of life be other-handed if they are made of antimatter?
__________________
"What you think you thought you saw you did not see." Agent J, MiB - Manhatten Bureau
Reply With Quote
  #14 (permalink)  
Old 04-March-2008, 08:03 PM
MeteorWayne's Avatar
MeteorWayne MeteorWayne is offline
Member
 
Join Date: Jan 2007
Location: High Bridge, NJ
Posts: 35
Default

Quote:
Originally Posted by Ronald Brak View Post
Pristine? Some of those meteorites landed in manure. Claims were made in 2000 that extraterrestrial life had been found in them. Strangely enough exactly the sort of life you find on a rock if you throw in the middle of a farmyard.

I don't know you well enough to assess possible sarcasm.

The possible life detected in the Martian meteorite was not anything like what you would find if you flung it in a barnyard. In fact it was like nothing on earth at all.

It was uniquely small, which is in fact one of the things that led to the current understanding that it was not life.

However, I would say the case is not closed; like many things in science, the investigation goes on.
Reply With Quote
  #15 (permalink)  
Old 04-March-2008, 10:58 PM
DrWho DrWho is offline
Member
 
Join Date: Jan 2008
Posts: 90
Default

Quote:
Originally Posted by MeteorWayne
It was uniquely small, which is in fact one of the things that led to the current understanding that it was not life.
Wasn't nano-bacteria theorized to actually exist on Earth and be the cause of many common 'mystery' ailments and conditions? I only have a vague recollection of this, having read about it years ago, so don't know if things have moved on since then or whether the idea has been debunked.
Reply With Quote
  #16 (permalink)  
Old 04-March-2008, 11:00 PM
MeteorWayne's Avatar
MeteorWayne MeteorWayne is offline
Member
 
Join Date: Jan 2007
Location: High Bridge, NJ
Posts: 35
Default

DrWho,
AFAIK, it remains speculative, and an area of continuing reserach.

I don't recall any legitimate connection to mystery ailments, but of course, nothing should be dismissed outright.
Reply With Quote
  #17 (permalink)  
Old 05-March-2008, 07:51 AM
Noclevername's Avatar
Noclevername Noclevername is offline
Senior Member
 
Join Date: Apr 2007
Posts: 10,606
Default

Quote:
Originally Posted by MeteorWayne View Post
I don't know you well enough to assess possible sarcasm.

The possible life detected in the Martian meteorite was not anything like what you would find if you flung it in a barnyard. In fact it was like nothing on earth at all.

It was uniquely small, which is in fact one of the things that led to the current understanding that it was not life.

However, I would say the case is not closed; like many things in science, the investigation goes on.
He couldn't have been talking about the Martian meteorite, as that didn't land in a farmyard. It landed in Antarctica.
__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort
Reply With Quote
  #18 (permalink)  
Old 06-March-2008, 01:01 PM
A.DIM's Avatar
A.DIM A.DIM is offline
Senior Member
 
Join Date: Nov 2002
Location: Kentucky
Posts: 3,346
Default

Quote:
Originally Posted by Noclevername View Post
No, just a confirmation that the materials of life are common. We already knew that the molecular precursors of life were common, this is just another refinement of that. Still just raw materials, nothing about panspermia, or actual extraterrestrial life.
And that's what's curious about it; couldn't biological processes on the meteorite's parent body as well be a plausible explanation for the excess handedness in these amino acids? Is it not a defining characteristic of life as we know it? Is it necessary to hold to some unknown natural process as the only explanation?
If the ingredients for Life are more abundant off planet than on, chemistry and physics are everywhere the same, and hallmarks of Life like this excess handedness in amino acids are found in meteorites free of earthly contaminates, why not suggest possible et life or panspermia?
__________________
"Where the telescope ends, the microscope begins. Which of the two has the greater view?" - Hugo

"Men occasionally stumble over the truth, but most pick themselves up and hurry off as if nothing had happened." - Churchill
Reply With Quote
  #19 (permalink)  
Old 06-March-2008, 01:03 PM
A.DIM's Avatar
A.DIM A.DIM is offline
Senior Member
 
Join Date: Nov 2002
Location: Kentucky
Posts: 3,346
Default

Quote:
Originally Posted by Noclevername View Post
He couldn't have been talking about the Martian meteorite, as that didn't land in a farmyard. It landed in Antarctica.
Right, he was referring to the Murchison meteorite which was strewn across pastures. Even still, this finding seems to reinforce what they found 10yrs ago, an excess left handedness in amino acids.
__________________
"Where the telescope ends, the microscope begins. Which of the two has the greater view?" - Hugo

"Men occasionally stumble over the truth, but most pick themselves up and hurry off as if nothing had happened." - Churchill
Reply With Quote
  #20 (permalink)  
Old 07-March-2008, 05:48 AM
Noclevername's Avatar
Noclevername Noclevername is offline
Senior Member
 
Join Date: Apr 2007
Posts: 10,606
Default

Quote:
Originally Posted by A.DIM View Post
And that's what's curious about it; couldn't biological processes on the meteorite's parent body as well be a plausible explanation for the excess handedness in these amino acids? Is it not a defining characteristic of life as we know it? Is it necessary to hold to some unknown natural process as the only explanation?
If the ingredients for Life are more abundant off planet than on, chemistry and physics are everywhere the same, and hallmarks of Life like this excess handedness in amino acids are found in meteorites free of earthly contaminates, why not suggest possible et life or panspermia?
Lack of evidence. There's nothing to suggest that handedness of spaceborne molecules is a result rather than a cause of handedness in known life. And space is also more abundant in conditions hostile to life than Earth is.

All we've proved is that we're made of common materials. Again.
__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort
Reply With Quote