A Medley of Potpourri is just what it says; various thoughts, opinions, ruminations, and contemplations on a variety of subjects.
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Monday, December 9, 2013
Thanks to Progressive Secular Humanist Examiner
When you meet people today who believe weird things, bear in mind you have no idea just how weird can be.
Mars: New Clues to Life in ‘Lake Doughnut’
David Strumfels -- the possibility that a 3.5-4 billion year old Mars might have had a habitat sufficiently Earthlike for (very simple) life to get started there is gradually getting stronger, though still by no means overwhelming. Which leads to a very small possibility that our life started there, got knocked off by an asteroid, reached our planet and flourished with its more permanent habitable environment. If true, one of the greatest scientific discoveries in history.
And now to the article...
The evidence mounts for long-ago microbes in a vanished body of Martian water
And now to the article...
The evidence mounts for long-ago microbes in a vanished body of Martian water
By Michael D. Lemonick Dec. 09, 2013
USGS / NASA
A mosaic of Mars made from a compilation of images captured by the Viking Orbiter 1.
It’s easy to get excited about the prospect of finding life on Mars—so easy that scientists have been getting worked up again and again and again and again over the past century and more. But it’s also easy to get too excited. NASA, for one, has learned from experience that announcing evidence even for long-extinct life on the Red Planet is a risky business, since it’s so easy to be wrong.
That’s why the agency is being so careful about a suite of reports from the Mars Science Laboratory (MSL), better known as the Curiosity rover, which has been sniffing around the Red Planet since its August, 2012 landing. The six papers, just published in Science, make no claim that they’ve found even the slightest evidence of life.
But what they have found is hugely important nonetheless: convincing evidence of a lake that rippled on the Martian surface some 3.6 billion years ago and that would have provided a fertile habitat for bacterial life—assuming the bacteria were actually there. “This environment would have been almost earthlike,” says Caltech planetary scientist and MSL project scientist John Grotzinger, “in terms of geochemistry and in the presence of water.”
(MORE: The Science Guy Wants Money For Space Exploration)
The water wasn’t big news: evidence that Mars was once a very wet place has been coming in since the early 1970’s, when the Mariner 9 orbiter first spotted what looked uncannily like dry riverbeds. Subsequent orbiters and rovers, including Curiosity, have found increasingly persuasive clues that young Mars had abundant streams, rivers and lakes—and since water is the most basic requirement for life as we know it, the odds that Mars could have hosted some sort of biology have kept going up too.
But water gets you only so far: organisms need food as well, and that’s what Curiosity has now found—potentially, at least. By drilling into exposed sedimentary rock at a site nicknamed Yellowknife Bay, the rover has uncovered minerals containing hydrogen, oxygen, carbon, nitrogen and sulfur. That’s a virtual feast for bacteria known as chemolithoautotrophs, which thrive on Earth in sulfurous caves and around so-called hydrothermal vents on the sea floor.
The lake that sloshed within Curiosity’s landing site in Gale Crater all those billions of years ago would, says Grotzinger, have been “a few meters to tens of meters deep.” And it would have had an interesting shape. If you imagine a crater with circular walls and a mountain in the middle, the lake would be a doughnut-shaped body of water—a moat around the mountain. “Maybe it didn’t go all the way around,” Grotzinger says. “The most conservative interpretation is that you’d have one-third of a donut, filled with water to a relatively shallow depth.
(MORE: NASA Detects Water on Five Planets)
But that might have been enough. The water persisted, the scientists believe, for tens of thousands of years at least, and perhaps for hundreds of thousands. That was ample time for layered sediments to accumulate and eventually solidify, first into clay and then into mudstone, which preserved the clues that Curiosity studied a few billion years later. And it was perhaps ample time for life to get started.
The discovery of the ancient lake was, in a sense, incidental to the mission. Curiosity’s primary area of interest has always been Mount Sharp, the mountain in the middle. Just before the rover landed, however, what Grotzinger calls a “massive mapping exercise” revealed that Yellowknife Bay showed signs of ancient inundation, so instead of charging over to the mountain right away, Curiosity lingered in the Bay first.
The careful probing that followed with MSL’s cameras, mass spectrometers, X-ray diffractometers and other instruments culminated in the drilling of two boreholes into the solid rock, which in turn yielded proof of an environment hospitable to bacteria, if they existed. Not only were there plenty of delectable minerals available to snack on, but the water itself was evidently low in salt (“it was practically freshwater,” Grotzinger says), and neither especially alkaline nor especially acidic. “Ten years ago,” he says, “we found evidence for water, but the salinity was so high it would have had the texture of honey.”
(MORE: New Take on an Ancient Mystery: How the Earth Got its Moon)
At first, the scientists worried that many of the minerals they found in the rock might have not have been present in the original lakebed itself, but might instead have been eroded from the crater walls and washed gradually into the lake. But the analysis revealed that the minerals showed few signs of weathering. They’d evidently been in the lake all along. “This lake is the original factory,” says Grotzinger, “where the clay was made.”
The absence of weathering does mean that while Mars was wet 3.6 billion years ago, it was also cold. “I like the analogy of the last glacial maximum on Earth,” says Grotzinger. At that time, about 25,000 years ago, much of the northern hemisphere was too cold for it ever to rain—something that weathers and erodes rocks relatively quickly—but water would still have pooled in low-lying areas. “Death Valley, the Las Vegas valley, those places would have been flooded,” he says. “I can imagine a scenario exactly like that.”
Put together, the new studies paint a picture of a hospitable place in which bacteria of a type we know exists on Earth could have thrived. The caveat—a big one—is that they say nothing at all about whether those bacteria in fact existed, though they do make an all but indisputable that that was possible.
The next step: look for organic carbon, which Curiosity will continue to do as it moves toward Mt. Sharp, its original target for exploration. “NASA has done really well with its ‘follow the water’ strategy,” Grotzinger says “Now we’re moving on to ‘follow the carbon,’” the other key element that all Earthly life, at least, is based on. And after that, in coming years, Mars exploration will inevitably move on to looking for fossil evidence of ancient life—and just possibly, of any life that has managed to survive to this day, deep below the Martian surface.
That’s why the agency is being so careful about a suite of reports from the Mars Science Laboratory (MSL), better known as the Curiosity rover, which has been sniffing around the Red Planet since its August, 2012 landing. The six papers, just published in Science, make no claim that they’ve found even the slightest evidence of life.
But what they have found is hugely important nonetheless: convincing evidence of a lake that rippled on the Martian surface some 3.6 billion years ago and that would have provided a fertile habitat for bacterial life—assuming the bacteria were actually there. “This environment would have been almost earthlike,” says Caltech planetary scientist and MSL project scientist John Grotzinger, “in terms of geochemistry and in the presence of water.”
(MORE: The Science Guy Wants Money For Space Exploration)
The water wasn’t big news: evidence that Mars was once a very wet place has been coming in since the early 1970’s, when the Mariner 9 orbiter first spotted what looked uncannily like dry riverbeds. Subsequent orbiters and rovers, including Curiosity, have found increasingly persuasive clues that young Mars had abundant streams, rivers and lakes—and since water is the most basic requirement for life as we know it, the odds that Mars could have hosted some sort of biology have kept going up too.
But water gets you only so far: organisms need food as well, and that’s what Curiosity has now found—potentially, at least. By drilling into exposed sedimentary rock at a site nicknamed Yellowknife Bay, the rover has uncovered minerals containing hydrogen, oxygen, carbon, nitrogen and sulfur. That’s a virtual feast for bacteria known as chemolithoautotrophs, which thrive on Earth in sulfurous caves and around so-called hydrothermal vents on the sea floor.
(MORE: NASA Detects Water on Five Planets)
But that might have been enough. The water persisted, the scientists believe, for tens of thousands of years at least, and perhaps for hundreds of thousands. That was ample time for layered sediments to accumulate and eventually solidify, first into clay and then into mudstone, which preserved the clues that Curiosity studied a few billion years later. And it was perhaps ample time for life to get started.
The discovery of the ancient lake was, in a sense, incidental to the mission. Curiosity’s primary area of interest has always been Mount Sharp, the mountain in the middle. Just before the rover landed, however, what Grotzinger calls a “massive mapping exercise” revealed that Yellowknife Bay showed signs of ancient inundation, so instead of charging over to the mountain right away, Curiosity lingered in the Bay first.
The careful probing that followed with MSL’s cameras, mass spectrometers, X-ray diffractometers and other instruments culminated in the drilling of two boreholes into the solid rock, which in turn yielded proof of an environment hospitable to bacteria, if they existed. Not only were there plenty of delectable minerals available to snack on, but the water itself was evidently low in salt (“it was practically freshwater,” Grotzinger says), and neither especially alkaline nor especially acidic. “Ten years ago,” he says, “we found evidence for water, but the salinity was so high it would have had the texture of honey.”
(MORE: New Take on an Ancient Mystery: How the Earth Got its Moon)
At first, the scientists worried that many of the minerals they found in the rock might have not have been present in the original lakebed itself, but might instead have been eroded from the crater walls and washed gradually into the lake. But the analysis revealed that the minerals showed few signs of weathering. They’d evidently been in the lake all along. “This lake is the original factory,” says Grotzinger, “where the clay was made.”
The absence of weathering does mean that while Mars was wet 3.6 billion years ago, it was also cold. “I like the analogy of the last glacial maximum on Earth,” says Grotzinger. At that time, about 25,000 years ago, much of the northern hemisphere was too cold for it ever to rain—something that weathers and erodes rocks relatively quickly—but water would still have pooled in low-lying areas. “Death Valley, the Las Vegas valley, those places would have been flooded,” he says. “I can imagine a scenario exactly like that.”
Put together, the new studies paint a picture of a hospitable place in which bacteria of a type we know exists on Earth could have thrived. The caveat—a big one—is that they say nothing at all about whether those bacteria in fact existed, though they do make an all but indisputable that that was possible.
The next step: look for organic carbon, which Curiosity will continue to do as it moves toward Mt. Sharp, its original target for exploration. “NASA has done really well with its ‘follow the water’ strategy,” Grotzinger says “Now we’re moving on to ‘follow the carbon,’” the other key element that all Earthly life, at least, is based on. And after that, in coming years, Mars exploration will inevitably move on to looking for fossil evidence of ancient life—and just possibly, of any life that has managed to survive to this day, deep below the Martian surface.
Climate Change Opens the Arctic to Climate Disaster -- Think Again
December 9, 2013
by John Light
The Greenpeace ship, the Arctic Sunrise, center, is anchored side by side with a Russian Coast Guard ship, left, near Murmansk, Russia on Oct. 9, 2013. Thirty Greenpeace activists and freelance journalists were initially charged with piracy after protesting at an oil platform in the Arctic. (AP Photo/ Evgeny Feldman)
In September, a large freighter made it through the Northwest Passage, traveling from Vancouver, BC, to Finland. It was the first vessel of its type to ever make the journey and demonstrated the potential to cut costs and shipping times using the new route. The ship was carrying coal for use by a steel producer. (soon it will be using natural gas -- David Strumfels)
Elsewhere in the Arctic, the Northern Sea Route (NSR), a passage maintained by Russian nuclear-powered ice breakers (which is perfect from a climate change perspective -- David Strumfels), saw 71 vessels pass through it. According to the Russian fleet, that figure is up 50 percent from last year. As recently as 2010, only four vessels made the voyage between the Barents Sea, north of Scandinavia and Western Russia, and the Bering Strait, between Siberia and Alaska. While the mandatory icebreaker escort costs, on average, $200,000 per voyage, NSR is becoming an increasingly viable shipping path from Europe to Asia — an alternative route, through the Suez Canal, would have taken two weeks longer. Supertankers carrying crude oil were among the most common vessels making the crossing.
DJ Strumfels -- has it also occurred to you that the polar passages are preferred because they are shorter and hence consume less fuel, fossil or otherwise?
Though summer ice cover in the Arctic has dropped by more than 40 percent over the past few decades, shipping companies remain divided over the promise of Arctic shipping. “It’s early days,” Gary Li, a senior maritime analyst with IHS in Beijing, told the Financial Times. “The Northern Sea Route probably needs another 20 or 30 years of climate change to make it fully viable. And even then, it’s got so many constraints.”
But the Arctic is seeing an increase in other new business as well. It is rich in fossil fuels. Experts guess that 22 percent of the world’s remaining undiscovered oil and gas reserves lie below ice at the top of the globe. One US Geological Survey study estimated that 43 of the 61 significant arctic oil and gas fields are in Russian territory, and the country has been ramping up fossil fuel exploration since 2008. Norway, Greenland, Canada and the US have followed suit.
DJS -- Get the facts. No comment needed here.
It’s an issue that came into national focus this year when Greenpeace activists and freelance journalists were arrested by Russia and charged with piracy while attempting to board the first oil platform to drill in the Arctic Circle. The charges were later reduced to “hooliganism” and the activists were released.
In the US, Shell Oil began exploring for oil up north in 2012. But after a drilling rig ran aground and the company encountered a slew of other problems — including fines for air pollution — it suspended its operations in 2013. They may remain suspended through 2014 as well.
In an attempt to control access to these new shipping routes and natural resources, nations are also moving to gain military influence in the Arctic. In 2007, a Russian submarine planted a titanium Russian flag at the base of the North Pole. And in September of this year, Russian President Vladimir Putin announced that the country was re-opening a Soviet-era military base in the Arctic, abandoned for two decades, to help support (and secure) the region’s sea lanes and natural resources. Canada is also holding an increasing number of military drills in the Arctic and is looking at stationing a permanent force there. Norway and the US are watching the region closely.
DJS -- OK here I agree with you about this.
But the jockeying for control of the region — to the point of countries establishing military bases — makes shipping executives concerned about routes like the NSR. “One thing that makes me nervous is that this route is in Russia’s hands,” a Norwegian shipping executive told the Financial Times. “If they suddenly want to triple rates or impose this condition or that condition, they can.”
And there’s a further irony: the effects of climate change could present new impediments to shipping and drilling in the region, like unpredictable weather.
Environmental groups are opposed to tapping Arctic fossil fuels that will in turn contribute to continuing climate change. Advocates point to the disastrous effect that pollution — in one worst-case scenario, an oil spill — could have on animal and human populations.
DJS -- all this shows is that "environmental groups" are no better informed than you, and deserve the same amount of audience.
“Even the best-prepared, best-equipped and most technologically advanced oil company has no business drilling for oil in the Arctic,” Frances Beinecke, president of the Natural Resources Defense Council, wrote in June. “It is simply not possible to do it safely here.” (DJS -- He just knows this, of course. “It is simply not possible to do it safely here.” is a vacuous non sequitur. No energy -- that's right, no -- is perfectly safe.)
David Strumfels Comments Further:
Thank you, Professor Light. We'll all just burn wood and coal and see how that works out for 7+ billion people on this planet. Do you think even a billion will survive you're regressive policies? Don't you care?! On the other hand, if we find (and we probably will) lots of natural gas, we can replace coal with it, saving tens of thousands of lives per year (you're hearing this right, just check the facts) and drastically reducing CO2 emissions and potential further warming.
Are Wormholes Everywhere?
Posted by Greg Kestin on
As far-out as wormholes sound, they are described by of Einstein’s theory of general relativity, the same theory that describes the force of gravity. General relativity expresses gravity as the smooth bending of space and time. For example, the sun creates a dimple in the fabric of spacetime; the planets “roll” around the periphery of the dimple. A wormhole is more than a dimple, though. It is like a tunnel between two parallel sheets of spacetime.
The details about wormholes remain fuzzy, but new research suggests that they may be fundamentally related to quantum entanglement. Quantum entanglement is a phenomenon where pair of objects are bound together. No matter how far apart they fly, they will “know” about each other—even if they are on opposite sides of the galaxy. Which, when you think about it, sounds a lot like a wormhole.
A pair of independent teams arrived at the same conclusion. Here’s Katia Moskvitch, writing for AAAS Science Now:
Kristan Jensen of the University of Victoria in Canada and Andreas Karch of the University of Washington, Seattle, start by imagining an entangled quark-antiquark pair residing in ordinary 3D space, as they described online on 20 November in Physical Review Letters. The two quarks rush away from each other, approaching the speed of light so that it becomes impossible to pass signals from one to the other. The researchers assume that the 3D space where the quarks reside is a hypothetical boundary of a 4D world. In this 3D space, the entangled pair is connected by a kind of conceptual string. But in the 4D space, the string becomes a wormhole.Such pairs of particles are ubiquitous, though we don’t know for certain whether wormholes exist between them. For now, these findings remain theoretical. We haven’t even found hard evidence of large wormholes yet, let alone microwormholes. Both remain hypothetical objects of thought experiments, but as we learned from Einstein, such musings can lead to great revolutions in physics.
Julian Sonner of the Massachusetts Institute of Technology in Cambridge then builds upon Karch’s and Jensen’s work. He imagines a quark-antiquark pair that pops into existence in a strong electric field, which then sends the oppositely charged particles accelerating in opposite directions. Sonner also finds that the entangled particles in the 3D world are connected by a wormhole in the 4D world, as he also reported online on 20 November in Physical Review Letters.
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