Starship Asterisk*

A Crumbling Layered Butte on Mars

Explanation: What is this unusual mound on Mars? NASA's Curiosity rover rolling across Mars has come across a group of these mounds that NASA has labelled Murray Buttes. Pictured is a recently assembled mosaic image of one of the last of the buttes passed by Curiosity on its way up Mt. Sharp -- but also one of the most visually spectacular. Ancient water-deposited layers in relatively dense -- but now dried-out and crumbling -- windblown sandstone tops the 15-meter tall structure. The rim of Gale crater is visible in the distance. Curiosity continues to accumulate clues about how Mars changed from a planet with areas wet and hospitable to microbial life to the dry, barren, rusted landscape seen today.

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In the center of the scree are more than ten rocks whose surface have multiple round nodules.
All the other rocks have flat planes as would be if cleaved from sedimentary formation.

What are the nodules?
Sedimentary conglomerate?

Did Curiosity have a close look to be sure they were not signs of life (eg coral-like)?

Interesting, and the left side is a clear shot, but the right is dusty, and you can't see. Left "appears" to have a shoreline appearance, and then lowered...

:---[===] *

There may be clues to how Mars changed to a dry, barren, rusted landscape in the Bisti/De Na Zin Wilderness of New Mexico. Despite life all around it, that area continues to surprise me in how lifeless it is, how the rocks just erode and decay, and mineral shards spill out, but nothing will grow there. Earth has a hospitable atmosphere, and although New Mexico experiences drought, we get enough rain for things to grow averywhere else but in the Bisti Badlands. It may be that the concentraion of mineral salts is way too high to permit life. It's a eerie place. Perhaps Mars experienced a period of severe drought, and the salinity of the remaining water was just too great to give the remaining life enough time to adapt, so everything died. After that, with nothing to hold the water, or participate in a hydrologic cycle, the water evaporated away to the thinner atmosphere and low gravity.

The primordial atmosphere of Mars may have resembled that on early Earth: mainly nitrogen and carbon dioxide, and negligible oxygen. Rain waters, acidified by carbonic acid, dissolved metals (ferrous iron included) on land, and rivers carried weathering products to the seas. The high concentration of CO2 in the Martian atmosphere may have caused the greenhouse effect which kept surface temperatures at a life-supporting level for (hundreds of?) millions of years.
The first life on Earth likely was photosynthetic. Evidence: Banded Iron Formation (BIF) deposits 4+ billion years of age: free oxygen generated by floating algal mats was immediately and totally consumed by water-soluble ferrous iron (Fe2+, greenish in color) that immediately precipitated as ferric iron (Fe3+, rust red in color) that - together with pale colored silica - deposited on ocean floor as BIF.
On Mars - and on any young planet, early Earth included - find FIB (apply geology and geophysics: magnetometer, gravimeter..) and you'll find the microfossil you're looking for.
The red color of Martian soil may - at least partly - result form the wind erosion of outcropping BIF deposit(s) hiding..where?

Referring to Discussion in APOD 2016 Oct 03, the model presented above may be applied in reverse order like this:
Find a microfossil in a meteorite (or on an asteroid, comets included), and you have found the representative of first life on pre-collision Proto-Earth.
How about finding a microfossil in a meteorite originating from Mars?

Can you imagine a human colony on the surface of this planet? Growing crops, to feed themselves ... somehow? With no water to speak of? Their energy sources being ... what? Not solar power, from a very very distant sun.

Kaarlo wrote:
Referring to Discussion in APOD 2016 Oct 03, the model presented above may be applied in reverse order like this:
Find a microfossil in a meteorite (or on an asteroid, comets included), and you have found the representative of first life on pre-collision Proto-Earth.

How about finding a microfossil in a meteorite originating from Mars?

https://en.wikipedia.org/wiki/Allan_Hills_84001

neufer,
Thank you for the link.
The ALH84001 structures are not regarded as fossils based (mainly) on their too small a size.
However, here’s a few points to ponder:
*Life (on any planet) starts molecular - i.e. exremely small - in size. UV-radiation from the central sun splits elemental bonds in primordial methane and CO2. Oxygen thus released is consumed by ferrous iron while the resulting (organic) radicals combine until – through countless trials and errors - self-supporting life is formed.
Note: this reaction takes place during daytime (in light) only, hence (day-night) banding in BIF.
*Magnetite contained in ALH-structures can hardly be but indication of photosynthetic oxygen generation and ferro-to-ferri oxidation in the environment.
*PAHs in meteorites do not necessarily warrant life but indicate the potentiality for life to spark - or to have sparked - in the system.
The ALH84001 structures may very well be real microfossils, thus the prevailing negative theories warrant serious re-evaluation.

That's a nice butte shot.

Is this a true color image?

heehaw wrote:Can you imagine a human colony on the surface of this planet? Growing crops, to feed themselves ... somehow? With no water to speak of? Their energy sources being ... what? Not solar power, from a very very distant sun.

No water on Mars? Au contraire... There's plenty to be found, but it's locked up as ice in the Polar caps and subsurface permafrost. Exposed to the thin Martian atmosphere, water ice quickly sublimates as vapor and never has the chance to exist as a liquid. However Human technology could find ways to extract and store water.

Those multilayered formations are testament a wetter, warmer past of Mars' history billions of Earth years ago. Did Life have a chance to form back then? I think probably not, but who's to know?

Kaarlo wrote:
The ALH84001 structures are not regarded as fossils based (mainly) on their too small a size.

ALH84001 structures are not too small in size
...but they cannot be regarded as definitive proof for Martian fossils.

"Morphology alone cannot be used unambiguously as a tool for primitive life detection."

https://en.wikipedia.org/wiki/Allan_Hills_84001 wrote:

[b][color=#0000FF]Electron microscope reveals chain structures in meteorite fragment ALH84001[/color][/b]

---

<<Under the scanning electron microscope structures were revealed that some scientists interpreted as fossils of bacteria-like lifeforms. The structures found on ALH84001 are 20–100 nanometres in diameter, similar in size to theoretical nanobacteria, but smaller than any cellular life known at the time of their discovery. In November 2009, a team of scientists at Johnson Space Center argued that since their original paper was published, the biogenic hypothesis has been "further strengthened by the presence of abundant fossil-like structures in other Martian meteorites." However, the scientific consensus is that "morphology alone cannot be used unambiguously as a tool for primitive life detection." Interpretation of morphology is notoriously subjective, and its use alone has led to numerous errors of interpretation.

Ergo...they are always looking for fossils on Martian meteorites but that path has limitations.

Someday someone will design an app that allows one to take the image of a 2 meter high person and move it around the picture and it will automatically portray the respective height of that person in the perspective of the picture so that one will have an approximate standard to imagine the relative size. "Fifteen meters high:" and what would be the relative size of a man superimposed on that image at various locations?

Something like this tells a much more interesting story. That cap rock is visible in the background as well. That layer was once continuous. On Earth that's no surprise because chemical weathering helps break down the softer rocks below and water erosion removes loose material. On Mars, either there was a lot of active water erosion in the past, or material has been removed by wind. But a LOT of material has been moved.

I'm just an amateur here, but it seems to me that this structure and surrounding sedimentary rock formations would be a great place to look for evidence of life. I would bet that there are folks in NASA who would give anything to be up there right now with a rock hammer and an electron microscope, just to see what they could find. Think of the adventure and opportunity for discovery.

There was running water on Mars probably quite recently - maybe still is. See this: https://acrobat.com/#d=goS32GApItpLaosC9AqSDg

Kaarlo wrote:The first life on Earth likely was photosynthetic. Evidence: Banded Iron Formation (BIF) deposits 4+ billion years of age: free oxygen generated by floating algal mats was immediately and totally consumed by water-soluble ferrous iron (Fe2+, greenish in color) that immediately precipitated as ferric iron (Fe3+, rust red in color) that - together with pale colored silica - deposited on ocean floor as BIF.
On Mars - and on any young planet, early Earth included - find FIB (apply geology and geophysics: magnetometer, gravimeter..) and you'll find the microfossil you're looking for.

The idea you express here is sound, but it's an overstatement to say that the first life on Earth was likely photosynthetic. Early life, certainly. But photosynthesis is a complex process that probably required significant time to evolve. The existence of non-photosynthetic autotrophs today, as well as an understanding of the conditions on the very young Earth, strongly support the notion that such life forms may have evolved earlier and are at least as likely to have been the first life as any photosynthetic organisms.

The earliest beginnings of Life on Earth were only complex protein chains. How stable they were in an aqueous environment (which at the time was probably quite toxic by today's standards) is not known. Nor is it known by exactly which process caused the protein chains to become self-replicative. Lots of educated guesses such as lightning and volcanism, but all the same we'd have to know what conditions on either Earth or Mars were like 4 - 5 billion years ago - and we don't.

But hope springs eternal in the search...

Asterhole wrote:The earliest beginnings of Life on Earth were only complex protein chains. How stable they were in an aqueous environment (which at the time was probably quite toxic by today's standards) is not known. Nor is it known by exactly which process caused the protein chains to become self-replicative. Lots of educated guesses such as lightning and volcanism, but all the same we'd have to know what conditions on either Earth or Mars were like 4 - 5 billion years ago - and we don't.

But hope springs eternal in the search...

I think there is good reason to believe we will learn what conditions were like on Earth from the very beginning. I think there's good reason to believe that we'll create primitive lifeforms in the lab under those conditions. These things will let us say, with reasonable certainty, how life originated on Earth (and help us in our search for it elsewhere). But it's entirely possible that there simply is no surviving physical evidence from the time life formed here, so we'll end up good theories that are well supported by indirect evidence only.

Chris,
With "photosynthesis" I mean here this: "central-sun-UV-radiation-driven-oxygen-gneration-in-primordial-hydrocarbons-and-CO2".
Since such term is a bit clumsy, I simply used photosynthesis. Perhaps you coud suggest a proper - possibly a new - term instead?

Kaarlo wrote:Chris,
With "photosynthesis" I mean here this: "central-sun-UV-radiation-driven-oxygen-gneration-in-primordial-hydrocarbons-and-CO2".
Since such term is a bit clumsy, I simply used photosynthesis. Perhaps you coud suggest a proper - possibly a new - term instead?

No alternate term. But "photosynthesis" is not so good, since it already has a different and well understood meaning.

Also, there's very good reason to believe that the first life utilized chemical energy unrelated (except in the most distant way) to the Sun. So again, I'd avoid saying that the first life "likely" depended upon solar radiation in any form.

jnnel@shaw.ca wrote:In the center of the scree are more than ten rocks whose surface have multiple round nodules.
All the other rocks have flat planes as would be if cleaved from sedimentary formation.

What are the nodules?
Sedimentary conglomerate?

Did Curiosity have a close look to be sure they were not signs of life (eg coral-like)?

jnnel
Down at the bottom of this image, near that same butte, lies a similar rock to the ones you are asking about Note the same "Nodules"

Asterhole wrote:

heehaw wrote:Can you imagine a human colony on the surface of this planet? Growing crops, to feed themselves ... somehow? With no water to speak of? Their energy sources being ... what? Not solar power, from a very very distant sun.

No water on Mars? Au contraire... There's plenty to be found, but it's locked up as ice in the Polar caps and subsurface permafrost. Exposed to the thin Martian atmosphere, water ice quickly sublimates as vapor and never has the chance to exist as a liquid. However Human technology could find ways to extract and store water.

Those multilayered formations are testament a wetter, warmer past of Mars' history billions of Earth years ago. Did Life have a chance to form back then? I think probably not, but who's to know?

All that is needed is a Biosphere (with an air lock) set into the ground and given an earthlike Atmospheric pressure and temperature. Once both are approaching that similar to Earth, the Permafrost would thaw and the water would be released in a liquid form

This seems a good object for observing the Martian angle of repose. Depending on the conditions under which it formed and the weathering which it has endured, we are left to view a pile of Martian history worthy of understanding.

While it does look more like a boobe than a butte I give NASA props for their naming conventions .