Tracing the canals of Mars

Oct 07, 2011 By Richard Milner
This series of images shows warm-season features that might be evidence of salty liquid water active on Mars today. Credit: NASA/JPL-Caltech/Univ. of Arizona

In a remarkable discovery, images taken over the past five years by the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA’s Mars Reconnaissance Orbiter, which circles Mars to photograph the planet, seem to indicate the presence of water there. For decades, space scientists searched the red planet without detecting the life-sustaining liquid, and concluded that it was bone-dry.

Last August, however, scientists found dozens of slopes across the southern hemisphere of where previously undetected dark streaks come and go with the seasons. When the planet heats up, the streaks appear and expand downhill, and disappear when it gets cold. Scientists think it may be evidence of melted, salty water running down slopes during the Martian summer.

Five image sequences from the Newton crater and one from the Horowitz crater show the black lines appearing near the tops of slopes and then growing into scores of “streaks” that remain for months until the cold weather returns and they disappear. At Newton Crater, photos indicate as many as 1,000 of these possible streams flowing down the slopes and into a basin.

Martian canals depicted by Percival Lowell.

If confirmed, the discovery would fundamentally change our understanding of Mars, lending support to the theory that the planet was once far more wet and warm, and would renew hope that it may be able to support life. But before back around 120 years ago, at least one prominent astronomer was convinced that Mars not only supported life, but was home to an advanced civilization that built an extensive network of canals to draw water down from supposed icecaps at the red planet’s poles to irrigate a world that was drying out.

The Man Who “Discovered Civilization” on Mars

These immense illusory earthworks (Marsworks?) had been studied in detail by one of the greatest astronomers of the late nineteenth and early twentieth century, the wealthy and socially prominent Percival Lowell. In his day, Lowell was far and away the most influential popularizer of planetary science in America. His widely read books included “Mars” (1895), “Mars and Its Canals” (1906), and “Mars As the Abode of Life” (1908).

Lowell was not the first to believe he saw vast canals on Mars. That honor belonged to the Italian astronomer Giovanni Schiaparelli, who in 1877 reported the appearance of certain long, thin lines he called canali, meaning channels in Italian, but he stopped short of attributing them to the work of intelligent Martians. (“Leave the Martians; take the canali.”) Lowell carried the matter much further. Captivated by these sketchily observed, and ultimately nonexistent phenomena, Lowell spent many years attempting to elucidate and theorize about them. The lines, he thought, must “run for thousands of miles in an unswerving direction, as far relatively as from London to Bombay, and as far actually as from Boston to San Francisco.”

He thought the red planet must once have been covered by lush greenery, but was now desiccated; the “canals” were an admirable attempt by intelligent and cooperative beings to save their home planet.

The Canals of Mars became one of the most intense and wrongheaded obsessions in the history of science, capturing the popular imagination through dozens of newspaper and magazine articles, as well as such classic science fiction as “The Princess of Mars,” a pulp classic by Edgar Rice Burroughs, who also created the immortal “Tarzan of the Apes.” (Burroughs had a rare gift for knowing what the public would adore, from Ape-Men to Little Green Men.)

Percival Lowell in the observatory he built at Flagstaff, Arizona. Credit: Mary Evans Picture Library

Despite the fact that his “canals” and elaborate descriptions of Martian civilization turned out to be the product of self-delusion (though not a deliberate hoax), Lowell’s name remains honored in the annals of astronomy. To pursue his misguided obsession, he founded and funded one of the great observatories on a 7,200-foot mountain peak he named Mars Hill, near Flagstaff, Arizona. There he scrutinized the heavens, and particularly Mars, with, his own custom-built twenty-four inch refracting telescope, built in 1894, which became a marvel of the age.

In 2012, the Lowell Observatory, which now hosts 80,000 visitors a year, will complete its 4.3-meter Discovery Channel Telescope. That state of the art instrument will vastly expand the breadth of its research capabilities and bring new images of the universe to hundreds of millions through direct television transmissions.

And if Earth is not invaded by Martians or pummeled by giant asteroids within the coming week, my next story will reveal how Lowell’s beloved Martian inhabitants were shot down by another remarkable scientist: none other than Charles Darwin’s junior partner in evolutionary theory, Alfred Russel Wallace.

Explore further: Prospects for the 2014 Perseids

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Peteri
2.8 / 5 (4) Oct 07, 2011
This article appears to be simply rehashing old news and throwing it together with a bit of history relating to Lowell and his "canals" of Mars. It's hardly a news item - more a lame excuse to have an article on PhysOrg!
Pirouette
1.6 / 5 (7) Oct 07, 2011
I see that NASA, JPL and the University of Arizona continues to slowly spoon-feed the American public and the world in general the fact that liquid does flow on Mars. I discovered water, a gel or oil flowing on the planet just by zooming in and out across my downloaded JP2 large file from the HiRise website, several years ago. I have also found life forms in other JP2 files which I retain on DVDs. There are several species of Martian life forms that possibly utilize the liquids.
I wish that the NASA would just own up and admit to the whole thing right away and politics, power and control over people be damned. Here's the link to my webpages:

www.marscritters.blogspot.com

Have a magnifying glass available, please. The humanoid life forms are semi-transparent and they are huge, with human-like faces. It is possible that they live underground which is why they are not readily seen by the HiRise cameras.
Pirouette
1.8 / 5 (6) Oct 07, 2011
After I found them in one JP2, I contacted NASA regarding what I thought looked a creek or a river running not very far from where I found the life forms in the hillside within the crater. But I was told that there is no liquid water flowing on Mars, so I left it at that. Other researchers have also found pools of liquid that appears to be water on Mars. The pictures have the classic tell-tale darker area of soil or sand just above the liquid and one can see rocks within the walls and floor of the depression in the ground that holds the clear
liquid.
People on Earth will grow old and die long before the NASA finds it safe enough for their funding to continue, to find it prudent to reveal the presence of liquid water and a present civilization on Mars.
Nanobanano
5 / 5 (4) Oct 07, 2011
Well, I find that there actually seems like there just might be a chance for liquid water to exist very slightly above the triple point, but I fail to understand how the temperature and pressure requirements would be maintained from daytime high through night time low.

I admit I didn't think there would be a window for this to work at first, but it turns out the Mars' average air pressure is just above the triple point, and the temperature ranges do fall right in the middle of what is possible in the Martian summer.

Also, in the photographs, you can clearly see evidence of "some kind" of erosion in the form of the bright areas near the darker streaks. It looks sort of like the "shifty" terrain you'd see in dunes at a beach or desert.

There is an alternate explaination, in that seasonal deposition and sublimation of water-ice or CO2 ice could cause movement and changes in the soils, which may show up as streaks, but that is admittedly quite a stretch.
Nanobanano
5 / 5 (4) Oct 07, 2011
If I'm looking at the image correctly, it seems to be some sort of windward vs leeward effect going on, sort of like weather on earth over mountain ranges.

Perhaps the air rushing down the slopes compresses to a higher pressure, allowing liquids to form at the precise moment the triple point is exceeded.

You see effects like this with fog and rain in mountains and canyons on earth.

This is hard to explain without "some" kind of liquid.

I thought of wind driven sand, water-ice crystals, or CO2 ice, being moved around with the seasons and exposing darker soils below, but none of those explain the channeling effect, which is, in these frames, even visible in the off-seasons before the dark streaks show up; Suggesting this may in fact be small "tributary" sized stream beds which are only active a few weeks or months per martian year.

There are color changes elsewhere in the images with the seasons, but certainly nothing as pronounced as the streaks in the central area.
Shootist
5 / 5 (1) Oct 07, 2011
(Burroughs had a rare gift for knowing what the public would adore, from Ape-Men to Little Green Men.)


Sorry. Dejah Thoris is hardly a little green man. http://overlander...21529693
Nanobanano
5 / 5 (2) Oct 07, 2011
Another thing I just thought of that I didn't consider previously.

The triple point of water COULD be exceeded in the ground, or at the base of a layer of water-ice, simply due to the weight of material above itself.

So for example, a thin layer of water-ice might melt under it's own weight and then slide down the hill side, or spread out through the soil.

The soil there "looks" sandy, though that could be an optical illusion, but I'm sure everyone knows how wet sand appears darker than dry sand. Just think of the beach at a river or ocean.

This is easily the strongest evidence I've seen for a "liquid" flowing on Mars.
baudrunner
5 / 5 (1) Oct 08, 2011
There certainly appears to be some kind of glaciation, probably of water, which would liquefy in summer during daytime temperatures which can exceed 70 degrees F. The only factor keeping the water below the surface is the generally frozen state of that surface. Add a little heat, and the water is released.