Mars Orbiter Finds Evidence For Ancient Rivers, Lakes

Cowards Anonymous points out news that studies based on data from the Mars Reconnaissance Orbiter have found that vast regions of Mars contained rivers and lakes when the planet was young. The studies also suggest that the water existed for quite some time, often in standing pools, which are conducive to the formation of basic organic matter. NASA provides a color-enhanced photo of a delta within a crater. Quoting: "The clay-like minerals, called phyllosilicates, preserve a record of the interaction of water with rocks dating back to what is called the Noachian period of Mars' history, approximately 4.6 billion to 3.8 billion years ago. This period corresponds to the earliest years of the solar system, when Earth, the moon and Mars sustained a cosmic bombardment by comets and asteroids. Rocks of this age have largely been destroyed on Earth by plate tectonics. They are preserved on the moon, but were never exposed to liquid water. The phyllosilicate-containing rocks on Mars preserve a unique record of liquid water environments possibly suitable for life in the early solar system."

Send the invading starships now!

Their obviously an underground civilization. Will make excellent troglodytes. Get their corbamite!

Martian Vampires

Mars is teeming with vampires in underground caverns. They've covered the surface with a layer of blood dust to protect themselves from the Sun's rays. It's time to start arming our probes and orbital satellite bases with SOLASERS, to focus the Sun's power through cracks we dig in their defenses.

Otherwise, the biters will just ride back to Earth our probes, and raise their earthling cousins into an army to destroy us while the Sun's back is turned.

Noachian Period?

What is that? Boy that sounds like a Cliff Claven quote if I've ever heard one. "Y'see Noam - it was back in the Noahchian period of Mahs when the mahtians would take baths in the wahtah and lakes. This has been proved with the phyllosilicahtes found up thah.

Re:Noachian Period?

Martian geological time [jps.net] is subdivided into a number of time periods [wikipedia.org] based upon major geomorphological features seen from orbit -- major crater basins, the density of craters (generally speaking, crater frequency was higher in the deep past -- as on the Earth's Moon), canyons and channels such as Valles Marinaris, and volcanoes. While it isn't possible to determine their exact numerical age, it is possible to figure out their relative age (i.e. the order of the events that made them). For example, the overlapping shapes of craters tells you which impact formed first. If a volcano has a crater on it, then obviously the volcano formed first and then the crater. If a channel is eroded into a crater, then the channel came after. That kind of thing. So, there's a reasonably detailed relative chronology for events on Mars, and this is divided into eras known as (from oldest to youngest) the Noachian, the Hesperian, and the Amazonian.

Using crater densities and the fact that rocks were recovered and dated on the Moon, it is possible to link the better-known chronology of the Moon to that of Mars. There are significant uncertainties of course, but generally speaking that allows people to estimate that the Noachian was from about 4.6 billion to about 3.5 billion years ago, essentially the time when the cratering frequency started to drop off on the Moon. There is ample evidence that at this time on Mars there was freely-flowing water on the surface, hence, "Noachian".

The pages cited above has some really nice charts and descriptions, and the wikipedia page has a map showing the distribution of the deposits of different ages.

Isn't that an image from the Radiohead videoclip?

All kidding aside, beautifull images, it's amazing to me that from searching for microscopic traces of water a few years ago we're now "finding data from NASA's Mars Reconnaissance Orbiter revealing that the Red Planet once hosted vast lakes, flowing rivers and a variety of other wet environments that had the potential to support life."

Re:Isn't that an image from the Radiohead videocli

The gist is that as the atmosphere was stripped away and the grew too cold and low pressure for surface liquid water to persist for long enough to cause obvious landforms, it was going into underground aquifers and ice deposits. Every now and then a big transient source of heat (volcanic eruptions or magma plumes in the mantle, and impacts, basically) deliver a big pulse of thermal energy that melts a large quantity of water. Result, landforms like canyons, areas with very large boulders that were carried from "upstream" by the floods, etc. There are other causitive agents, eg collapse of crater-rim walls releasing lake water, ice damn collapse, Milankovic cycles warming areas, polar wander... (and if the new idea about the lowlands results from a gargantuan impact are correct, it seems likely that the upper crust migrated significantly over the planet to reach an equilibrium position with the lowlands at one pole or the other, the Tharsis bulge (Olympus Mons et al) near the equator, etc.

Lakes!

Thar she blows!

Men of the Moon, quick! To the space whalers!

Clearing up some details

"'scuse me, 'scuse me, officer JPLNazi coming though... "

...vast regions of Mars contained rivers and lakes...

This has been OLD NEWS since the Viking orbiters, more than thirty years ago, though thanks to the demands of the mass media, the goldfish-like attention spans of the general public and the rigours of academic tenure, publishing, and funding rounds (not to mention PR teams at academic institutions, who often seem to know jack shit about the subject they're writing a press release on) it gets recycled every time there's a water-related Mars discovery. I'm sure I've seen three or four water-related stories based on MER (rover) research, then there's the Mars Express data, Mars Odyssey's spectrometer data (hint: why do you think Phoenix happened to land somewhere where there's water ice 5cm below the surface - luck?). Oh yeah and of course Phoenix is just about to drop ice scrapings into the TEGA oven [planetary.org] and cook out any water, carbonates, in fact everything else that vaporises at less than 1000 degrees C.

The significant aspects of the two new papers (one in Nature, on in Nature Geoscience) are indeed the phyllosilicates, more commonly known as clay minerals. (if you're thinking of the clay in your back garden, imagine it after lying in an Antarctic dry valley for a three plus billion years, in a near vacuum, and hammered with UV. To the layperson this is what Arthur Dent would have identified thusly: "well, it's rock, isn't it?" It adds to the evidence for medium-term (up to 10^6 years) periods of free-standing or flowing water on the surface at essentially every scale, from regional morphology such as flash flood outflow channels, river deltas, coastlines and the like down to rock formations that are clearly indurated, contain silica minerals (google 'Spirit Tyrone') or haematite (blueberries, which are concretions formed in water-saturated rocks) and vugs (voids left by water-soluble crystals.) When you wet particular kinds of rocks that Mars is known to have a lot of, you get clays (phyllosilicates) as a result.

By the way the NASA image isn't

"colour enhanced"

-- that's CRISM data overlaid on a visible-wavelengths image. (CRISM is a spectrometer and is the instrument that ID'd these minerals.)

...standing pools, which are conducive to the formation of basic organic matter.

This statement is, uh, mistaken. What it's getting at is the notion that long periods of exposure to water is generally considered to be probably very very important if not essential to early life. ("organic matter" would be anything with a carbon atom in it, e.g. coal, plastic, methane, oil... it's one of those words that means something totally different in particular scientific context. Like "metals" (tho' that means at leat three different things to different sciences...)

Much much more at a popular search engine near you.

Re:

This statement is, uh, mistaken. What it's getting at is the notion that long periods of exposure to water is generally considered to be probably very very important if not essential to early life. ("organic matter" would be anything with a carbon atom in it, e.g. coal, plastic, methane, oil..

Coal, plastic, methane, and oil are all byproducts of life. Coal is from plants, plastic is from humans, the vast majority of methane is from biogenic sources, and oil is from plants, animals, and bacteria.

The only carbon product you mentioned that might be formed without life is methane. The formation of methane usually involves water as either a reactant or product. In fact, simply burning methane produces water.

I don't think there is anything wrong with the statement you are disagreeing with" s

Re:

No. If you wield a magic wand and warm the planet to the point that the polar caps and underground ice melts, you've only got a few thousand / tens of thousands of years before it's all boiled off into space. Low gravity, no core magnetic field.

Taking it To the Streets

These cheap landers with specialized probes show just how much more powerful our science can be when we interact with its subjects through matter-on-matter operations, rather than just interacting with energy as we do in telescopes, or interacting with information as we do in simulations.

When we actually send a human to Mars, a "generalized probe" with sensory and mechanical amplification equipment, we'll really be getting to work, down to brass tacks.

Early wet Mars versus late wet Mars

These articles rarely mention that there are two camps in the scientific community, one of which is largely American, and rejects any evidence for recent liquid water on Mars, and the other of which is more European, and accepts it.

The Mars cratering model [psi.edu] indicates that a billion year old surface on Mars should have multiple 100 meter craters per square kilometer, and maybe ten 50 meter craters per square km . Basically, if you see a picture of the Martian surface, and there aren't lots of little craters on it, then that is not a billion year old surface, regard of what the press release says. It isn't hard [arizona.edu] to find such images. Here is another [arizona.edu], and another [arizona.edu].

Re:too bad

They had plenty of greenhouse gases. The problem was that after the geomagnetic field of Mars was lost, the solar wind was able to strip away the atmosphere, leaving it today at about 5 to 10 millibars (in contrast with the Earth which is about 1000 millibars).

Re:Once had life, but no more

Mars' magnetic field has not always been as weak as it is now. One theory is that as it's core cooled, the magnetic field vanished, allowing the solar wind to penetrate and blow away the atmosphere. If this turns out to be accurate it might be possible to teraform mars ( or rather, repair it ) by creating a magnetic field through artificial means.

Re:

Mars' magnetic field has not always been as weak as it is now.

One hypothesis I have brought forward is that Mars might have a reasonably strong dipole and is in a magnet field reversal right now, making the field at this epoch very non-dipolar. That is improbable, but not outlandishly so, and I believe is consistent with the data.

Re:

No we are not doomed in the case of a field reversal. There has been literally hundreds of field reversals during since the Jurasic and life survived without problems. We cvould survive as well with only minor ajustments (for instance magnetic compasses would not work and magnetic storms temporarily taking out power distribution systems more often etc.)

The difference is that the magnetic field on Mars did not come back allowing billions of years without a field thus stripping the atmosphere.

Yours Yazeran

Pla

Re:Once had life, but no more

our inevitable colonisation of Mars

Look, we are never, never, ever going to "colonise" Mars. There's no reason to do it except SF fantasy wish fulfillment or too much time spent watching scientifically nonsensical films and books. IT'S NOT GOING TO HAPPEN. James van Allen was right. There's no reason to go there when we can do anything humans can do with robots for a thousandth of the cost and risk. Yes, it's "slower" than spending a couple of hundred billion dollars over 20 years, but so what? Mars has been there for 4000,000,000 years; it's not going anywhere.

If you're very very lucky, your children or grandchilden may live long enough to see a manned landing; personally, I very much doubt it. Hmmm, I must get round to setting up that thingy on longbets.org ...

Re:Once had life, but no more

The experts said, "mechanised rail travel was impossible because people would suffocate from the change in air pressure", then they said heavier-than-air flight was impossible", then they said "supersonic flight was impossible because the aircraft would shake itself apart". Up until 60 years ago, traveling between the USA and Europe was on the order of months of time, rather than hours.

But developing the technology to allow for high speed travel for long distances is an evolutionary process. Good examples are the evolution of sea-going craft from simple coracles, currachs, log rafts, then wooden ships, paddle-steamers, iron-hull craft up to ocean liners and nuclear powered air-craft carriers.

Any kind of interplanetary travel would be the same - protecting the crew from the elements (radiation) is the first obstacle, then there is the problem of propulsion over a long period of time. And then there is the actual process of manufacture if the vessel cannot travel from the surface of a planet.

Re:

Unfortunately the parent post is right - space colonization in the foreseeable future is unlikely for many reasons that somehow seem glossed over by the "true believers".

Lets face the cold hard reality of space - it is both cold and hard. There's nothing out there but rocks. Nobody wants to live on cold hard rocks. Some people might go there for science, or out of the curiosity of a tourist, but nobody will ever want to make a life there.

I'm sure of this because people already have the opportunity to go liv

A relevant quote

This is somewhat appropriate for this discussion:

"When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong."
--Arthur C. Clarke

Re:

I think it goes without saying that humankind will eventually need more living space than what is offered here on Earth.

No--it goes without saying that humankind will eventually need to control its number in order not to overpopulate Earth. That's all.

Space migration? You will not migrate the billions that Earth can't sustain to Mars, at least not without completely exhausting our resources ...

Possibly mankind will move to space/Mars. But that means a few hundred or some thousands--not billions--of people w

Wrong. No new physics needed

People's desires to live apart don't trump the laws of physics I'm afraid

[If someone] finds a source of infinite free energy, lots of things become possible including colonising Mars

You're talking total tripe, because we don't need free energy nor wormholes nor warp drives nor any other nonexistent inventions nor any new physics to make travelling to Mars cheap and widely available. All we need is *time* (a lot of it) for our engineering systems to mature.

Travel is a matter of harnessing energy, and energy

Re:

It would explain why the planet is now a barren wasteland now... we used up all the water for brewing beer.

but Venus has no life

but the fact that Venus has no signs of life proofs that women do not really exist and are just the results of a fevered imagination. This handily explains why slashdot, a bastion of clear thinking, has no women.

Re:

Short answer: all eggs in one basket.

Earth wasn't always the almost paradise for human-like life that is still a bit today, almost all life was wiped several times in earth history. And that, without our "intelligent" intervention (why wait for a huge asteroid or a snowball earth period if we can destroy it all faster?). Don't waste money in this and humans will become a rich, but unfortunately extinct, race.

One of the ways of having a backup is to be also somewhere else, preferably self-sustained. Explorat