More results for the possibility of Life on Mars - Page 11

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dx


Posts: 1661

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PostPosted: September 2, 2011 8:45 AM 

There is no life on Mars, never has been and never will be!

yt
dx

Lin Liangtai


Posts: 24

Reply: 202



PostPosted: September 3, 2011 8:00 AM 

Amino acid molecules produced in the lab are 50% left handed and 50% right handed. However, amino acids in fossils can be uneven-handed (over 50% left-handed, for example). This unevenness or excess of left-handed amino acids is a sure sign of past life (note 1). This sign of past life is found in organic molecules in meteorites (notes 2, 3). So, organic molecules in meteorites are post-biotic fossils.

Note 1: “Homochirality probably constitutes the most reliable indicator of the biological vs. abiotic origin of organic molecules.” [link]


Note 2:"Fragments of the Tagish Lake meteorite contain amino acids that are predominantly left-handed, as in life." http://www.panspermia.org/whatsnew65.htm#110613

Note 3: “In the new research, the team reports finding excess left-handed isovaline (L-isovaline) in a much wider variety of carbon-rich meteorites.” [link]

Added on Sept. 3, 2011:
Explanation on fossils’ amino acids

When organisms die and form fossils, the percentage of their left-handed amino acids decrease gradually from 100%, then fluctuates around 50 % until the percentage finally becomes stable at 50%. Abiotic amino acids always are 50% left handed. So, small variations from 50% of left-handed standard (protein) amino acids indicate past life of the sample material.

Even-handed amino acids do not prove past life as they are found both in non-life, and in not-well-preserved fossils, and very ancient fossils. Uneven-handed standard amino acids prove origin in life as they are found only in well-preserved fossils.

Ref.: http://en.wikipedia.org/wiki/Amino_acid_dating#Principle

Kevin Author Profile Page



Posts: no

Reply: 203



PostPosted: September 4, 2011 8:52 AM 

Well Mars was once had active Volcanoes so this latest study on Rock Rafts here on Earth opens up further possibilities for life on Mars.

http://www.bbc.co.uk/news/science-environment-14748623

MPJ


Posts: 250

Reply: 204



PostPosted: September 13, 2011 4:23 AM 

Another quite contradictory article about Mars methane. The "scientific community" really has a hard time considering biology on Mars those positive measurements of things supporting and consistent with martian life is fiercely challenged as usual.
But as Mumma states in the article: "But a measurement is a measurement" - same goes for the Viking LRx as hard as it is. Very Happy

[link]

Serpens


Posts: xxx

Reply: 205



PostPosted: September 13, 2011 4:44 AM 

You can't really say that dx. What we can say is that no indication of life has been found to date. The possibility of microbial life deep underground exists and there is no way to prove a negative. As an example you can't prove that you don't own an elephant. Similarly you can't prove there is no life on Mars. But no lander has found any sign of life whatsoever on the surface (Despite the protestations the Viking experiment was a null result). Biological mediation is an expected element of geology on Earth, but to date everything on Mars appears to be abiotic.

Kevin Author Profile Page



Posts: no

Reply: 206



PostPosted: September 13, 2011 5:04 AM 

The TGO was an after thought following the Methane discovery yes it will do other work but nailing the existance and source of the Methane is its key objective.

Because it appears in Summer as does the leakages from the crater walls it suggests water ice and brines melt beneath the surface and could release trapped gasses.

Getting a mission to those craters for the summer leakage is hard because of the terrain so nothing is planned as yet.

MPJ


Posts: 250

Reply: 207



PostPosted: September 14, 2011 8:23 AM 

Interesting thought about a correlation of the more recent methane measurements in Mars' atmosphere and the Viking LR response:
Mars microbes may make methane: the Viking view:
http://spie.org/documents/Newsroom/Imported/003176/003176_10.pdf

Barsoomer


Posts: 344

Reply: 208



PostPosted: September 21, 2011 11:22 AM 

http://www.psi.edu/news/press-releases#clays

Younger smectites (2-3 billion years old) in Valles Marineris, indicating late neutral water conditions there.

We really need a mission to Valles Marineris. Instead of designing a rover and picking a safe location to go to, we should set our sights on Valles Marineris and then design a rover to safely go to it.

Barsoomer


Posts: 344

Reply: 209



PostPosted: September 21, 2011 11:34 AM 

http://geology.gsapubs.org/content/39/10/899.abstract

The abstract for the actual paper in Geology Journal.

MPJ


Posts: 250

Reply: 210



PostPosted: September 27, 2011 5:36 AM 

Indirectly related to Mars (in this article at least): Yellow Arctic snow could help detect life on Jupiter moon

[link]

In this article some yellow stains are discussed left by microbes using sulphur on ice/snow fields as a telltale biosignature. Reminded me a little of the white/yellow material at the top of the Tisdale rocks. Smile

Also it reports on methane eating microbes in cold salty springs which would be related directly to Mars and the detected atmospheric methane disequilibrium there.

MPJ


Posts: 250

Reply: 211



PostPosted: October 6, 2011 6:03 AM 

Hardy microbes survive high vacuum and intense UV irradiation!

Comparative Survival Analysis of Deinococcus Radiodurans and the Haloarchaea Natrialba Magadii and Haloferax Volcanii, Exposed to Vacuum Ultraviolet Irradiation:

"The haloarchaea Natrialba magadii and Haloferax volcanii, as well as the radiation-resistant bacterium Deinococcus radiodurans, were exposed to vacuum-UV (V-UV) radiation at the Brazilian Synchrotron Light Laboratory (LNLS). Cell monolayers (containing 105 - 106 cells per sample) were prepared over polycarbonate filters and irradiated under high vacuum (10-5 Pa) with polychromatic synchrotron radiation. N. magadii was remarkably resistant to high vacuum with a survival fraction of ((3.77 \pm 0.76) x 10-2), larger than the one of D. radiodurans ((1.13 \pm 0.23) x 10-2). The survival fraction of the haloarchaea H. volcanii, of ((3.60 \pm 1.80) x 10-4), was much smaller. Radiation resistance profiles were similar between the haloarchaea and D. radiodurans for fluencies up to 150 J m-2. For fluencies larger than 150 J m-2 there was a significant decrease in the survival of haloarchaea, and in particular H. volcanii did not survive. Survival for D. radiodurans was 1% after exposure to the higher V-UV fluency (1350 J m-2) while N. magadii had a survival lower than 0.1%. Such survival fractions are discussed regarding the possibility of interplanetary transfer of viable micro-organisms and the possible existence of microbial life in extraterrestrial salty environments such as the planet Mars and the Jupiter's moon Europa. This is the first work reporting survival of haloarchaea under simulated interplanetary conditions."

http://arxiv.org/abs/1109.6590

hortonheardawho


Posts: 3465

Reply: 212



PostPosted: October 20, 2011 10:29 AM 

Watched a fantastic NOVA program last night:

Finding Life Beyond Earth

Well worth the 2 hours to watch. The best presentation of the case for life beyond the Earth that I have ever seen.

Barsoomer


Posts: 344

Reply: 213



PostPosted: October 20, 2011 1:22 PM 

Yes, the show was excellent. It gave the first plausible explanation that I have seen for the Late Heavy Bombardment.

Barsoomer


Posts: 344

Reply: 214



PostPosted: October 20, 2011 1:39 PM 

[link]

Kevin Author Profile Page



Posts: no

Reply: 215



PostPosted: October 21, 2011 5:26 AM 

Arggh video not available, hopefully it will turn up here in the UK on one of our networks.

Fred


Posts: 73

Reply: 216



PostPosted: October 21, 2011 8:26 AM 


Serpens has an elephant. Yep, he does.

dx


Posts: 1661

Reply: 217



PostPosted: October 21, 2011 10:04 PM 

Kevin>>>

In your 214 above, looks like the picture of you and the refactor are collecting a few rays from the Sun. Any sunspots that day? Is that your scope?

Looks good on you Mr. Astronomer.

yt
dx

dx


Posts: 1661

Reply: 218



PostPosted: October 21, 2011 10:20 PM 

Serpens>>>

I agree on your 205 above with respect to the abiotic idea. If that's true from what I read about abiotic, then how does that same condition contribute to the Moon and its soil?

It sure would have been a wonderful sight to have the Moon with ALL Earth like living qualities orbiting overhead 250000 miles away. We could have populated that so easily. Instead we have a dead world in the 'goldilocks' zone. Amusing thoughts to consider.

yt
dx

yt
dx

LWS


Posts: 3062

Reply: 219



PostPosted: October 22, 2011 8:31 AM 

The dust on the moon looks dead, abiotic, dry as dust. The dust on mars does'nt. Go figure.

Winston

Kevin Author Profile Page



Posts: no

Reply: 220



PostPosted: October 23, 2011 3:44 AM 

Hi dx,

That is the telescope at the Hampstead Observatory here in London, I am an assistant there, recently we have counted as many as 35 sunspots! Last Wednesday the Sky at Night filmed from our observatory, my 2 minutes of fame!

My picture is now changed for winter, this is Sir Patricks Moore's 14" Newtonian Reflector, an amazingly good telescope that he built.

Mars returns this year and really looking forward to making some drawings of it.

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