The scale of things

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Saturn’s Mini-Moons | The scale of things

Postby Allegro » Tue Jan 15, 2013 8:42 pm

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Saturn’s Mini-Moons Align for Family Portrait
Universe Today, Nancy Atkinson | 14JAN13

Image
^ Saturn, its rings and three moons are visible in this image from Cassini. Credit: NASA/ESA

    It’s a good thing NASA labeled the moons in this image of Saturn, because they are pretty hard to see. But they are there, keeping each other company in this Cassini spacecraft image of Saturn’s night side. And as the Cassini team says, it seems fitting that they should do so since in Greek mythology, their namesakes were brothers.

    In Greek mythology these three were all sons of Iapetus (another of Saturn’s moons), and supposedly Prometheus and Epimetheus were tasked with creating humans. Prometheus was a pretty good sort, and gave gifts to humans like fire; Epimetheus gave humans evil – not so good. And famously, Atlas ended up having the weight of the world on his shoulders.

    But in science, Prometheus the moon is about 86 kilometers across (53 miles) and is located just inside the F ring in this image, while Epimetheus is about 113 kilometers across (70 miles) and is farther from the rings, due right of Prometheus in this image. Atlas is the tiny guy 30 kilometers across (19 miles) and can be just barely seen between the A and F rings almost right below Epimetheus.

    This view looks toward the unilluminated side of the rings from about 30 degrees below the ringplane. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Sept. 19, 2012.

    The view was obtained at a distance of approximately 2.2 million kilometers (1.4 million miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 96 degrees. Image scale is 128 kilometers (80 miles) per pixel. Epimetheus has been brightened by a factor of 1.5 and Atlas’ brightness has been enhanced by a factor of 3 relative to the rings and Prometheus to improve visibility.

    You can see an unlabeled version here.
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Dark Nebula Hides Star Birth | The scale of things

Postby Allegro » Thu Jan 17, 2013 3:01 am

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Dark Nebula Hides Star Birth
Universe Today, Nancy Atkinson | 16JAN13

Image
^ A new image from ESO shows a dark cloud where new stars are forming along with a cluster of brilliant stars that have already emerged from their dusty stellar nursery. Credit: ESO/F. Comeron.

    Dark nebulas, or dark clouds in space are intriguing because they appear to be “holes” in the sky where there aren’t any stars. But they really are just blocking our view. Also called absorption nebulas, these dark, smokey clouds of gas and dust block light from the regions of space behind it. This new image from ESO shows a dark cloud called Lupus 3 along with a cluster of brilliant stars.

    While the dark cloud and the bright cluster of stars appear to be very different, they are in fact closely linked. The cloud contains huge amounts of cool cosmic dust and is a nursery where new stars are being born. We likely wouldn’t be able to see the absorption nebula unless it was silhouetted against the much brighter region of space produced by the star cluster, since absorption nebulas do not create their own light.

    As light from space reaches an absorption nebula it is absorbed by it and does not pass through. It is likely that the Sun formed in a similar star formation region more than four billion years ago. The stars seen here are probably less than one million years old.

    Lupus 3 lies about 600 light-years from Earth in the constellation of Scorpius. The dark section shown here is about five light-years across
    .

    The new picture was taken with the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile and is the best image ever taken in visible light of this little-known object.

    Source: ESO
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Milky Way’s center? “My God, it’s full of stars!”

Postby Allegro » Sat Jan 19, 2013 12:44 pm

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To Surf a Hundred Million Stars | Phil Plait
Bad Astronomy | Saturday, 19JAN13

Image
^ The center of the Milky Way galaxy as seen from the Earth. Image credit: Stéphane Guisard/ESO/GigaGalaxy Zoom

    So, whatcha doing today?

    Forget I asked, because after you click on this link, your day will be gone. Poof! Vanished, since you will find yourself buried in a magnificent, massive of the center of the Milky Way galaxy.

    And when I say massive, I mean it’s friggin’ HUGE: 24,000 x 14,000 pixels! That’s a total of a staggering 330 million pixels. It’s a combination of three images (one each in red, green, and blue to produce a true-color final product), so it’s actually—and I can’t believe I’m typing this—the combination of a billion pixels of information.

    Did I mention it’s zoomable and scannable? No? Well, there goes your day.

    The image, taken by my friend Stéphane Guisard at the ESO’s Paranal Observatory in Chile, spans an area of the sky roughly 30° x 20°, or about twice the area of the sky you can cover up with your outstretched hand. That’s a lot of territory. Taken as part of the GigaGalaxy Zoom project, it’s a mosaic of 52 fields shot over 29 nights for a total of 200 hours of exposure over 1200 separate photos.

    ImageThe sheer number of stars in this image is crushing my mind. When you look at the picture above (which is only a part I cropped out from the full-size shot), you can see a whitish glow. Those are stars. Individual stars, millions of them, too small to see at the scale shown, but adding together to make that glow.

    Here, let me show you. Inset here is a small piece of the image above, showing some of the background stellar glow and some of the dark clouds—huge regions of space filled with dust, which blocks the light from stars behind it. The white box outlined in the picture here looks like it’s mostly just filled with white haze, right? Well, let’s blow that piece up a bit and see what’s what:

    Image

    To coin a phrase: “My God, it’s full of stars!”

    Look at all of them! And then compare the size of this small piece of the picture to the whole thing… and realize this is only a tiny fraction of the stars in the galaxy. There are tens of millions of stars in the whole zoomable picture at least, but hundreds of billions in the Milky Way. In other words, this huge picture crammed full of stars shows less than a thousandth of all the stars in our galaxy!

    Now you may see why this picture makes my brain hurt.

    And if, after all that, you still haven’t had enough, the GigaGalaxy Zoom project has other incredible pictures that will melt your brain.

    And this is why I never, ever get tired of astronomy. There’s so much to see! It would take a million human lifetimes, and even then we’d only barely have begun.
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Thor’s Helmet in Canis Major | The scale of things

Postby Allegro » Sat Jan 26, 2013 12:47 pm

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Incredible Astrophoto: Thor’s Helmet in Canis Major
Universe Today, Nancy Atkinson | 25JAN13

Image
^ Thor’s Helmet Nebula (NGC 2359) in the constellation of Canis Major. Credit and copyright: Rolf Wahl Olsen.

    At first glance, you might expect this beautiful image to be from a big ground-based observatory or even one of the space telescopes. But this image was taken by “amateur” astronomer Rolf Wahl Olsen. We’ve featured his work before, and he’s done amazing stuff – such as the first amateur image of another solar system — but even he says this latest image of an emission nebula might be his best image to date.

    It’s a stunning look at what is known as Thor’s Helmet. This helmet-shaped feature (complete with wings!) is an emission nebula is located in the constellation of Canis Major, about 15,000 light years from Earth. The nebula is a large expanding bubble illuminated by a central star in its last stage of life — a massive Wolf-Rayet star which is shedding its outer layers of gas at an extremely high rate due to intense radiation pressure. Wolf-Rayet stars are thought to represent a brief stage of evolution near the end of life for giant super massive stars; the last unstable phase before the star explodes as a brilliant supernova.

    The nebula is some 30 light years in diameter, is embedded among a dense star field consisting of thousands of multi-colored stars, adding more beauty to the scene.

    Resume.
Last edited by Allegro on Sat Jan 26, 2013 3:28 pm, edited 1 time in total.
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Perfect Spiral Galaxy M74 | The scale of things

Postby Allegro » Sat Jan 26, 2013 1:16 pm

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The Stunning Beauty of the Perfect Spiral Galaxy M74 | Phil Plait
Bad Astronomy | Saturday, 26JAN13

Image
^ Image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona

    Q) Why should never ask for directions from an astronomer?

    A) Because we think 300,000,000,000,000,000,000 kilometers is “nearby”.

    It’s really true. Case in point: the nearby face-on spiral galaxy M74:

    I know, right? It’s gorgeous! And at 32 million light years away, it’s actually fairly close as galaxies go. There are many closer, but few displayed so wonderfully for us to see.

    I love spiral galaxies. It’s a combination of their symmetry, the pattern, the colors, and the simple majestic beauty. M74 is an example of all of these characteristics. It has a simple 2-armed structure, each apparently unwinding from the center, splaying out at the galaxy’s edge. There are numerous spurs; short straight branches which stick out from the main arms. These add to the pinwheel-like look of the galaxy, too.

    In this picture, taken by friend-of-the-BA-blog Adam Block using the 0.8 meter (32”) Schulman Telescope (RCOS) on Mt. Lemmon in Arizona, you can see the overall blue color of hot, young, massive stars, their fierce light dominating, even though by number they are only a tiny fraction of the 100 billion or so stars in M74fainter stars are far more numerous, but their light is feeble compared to the blue powerhouses.

    You can also see the reddish-pink glow of gas tracing the arms, where new stars are being born and lighting the gas up. Hydrogen in those clouds emits light in the red part of the spectrum, so even from 300 quintillion kilometers away, it’s easy to pick out where the stellar nurseries are.

    Image
    ^ Image credit: Spitzer Space
    Telescope’s infrared view of M74.
    NASA/JPL-Caltech/Wikipedia/
    Médéric Boquien
    There’s lots of dust in the galaxy, too; molecules of various dark materials created when stars are born, and also when they die. They block the visible light emitted by the stars and gas, leaving dark lanes behind. If you look in the infrared, like in the Spitzer Space Telescope image inset here, the dust itself glows, and you can see the dust follows the spiral arm structure closely, too.

    I have to hand it to Adam. M74 is such a classic spiral that it’s observed by every major telescope, including Hubble. With that ‘scope, immense amounts of detail can be seen, but the galaxy is so big you can only view one part of it. In Adam’s picture we get the overview, standing back, so to speak, and take in the whole sight. Our gaze can lovingly linger over the entire system, letting us marvel that the Universe displays extraordinary beauty on a scale that staggers the mind… even when it’s nearby.
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M51, the Whirlpool Galaxy | The scale of things

Postby Allegro » Tue Jan 29, 2013 4:33 am

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Drown Your Brain in the Whirlpool Galaxy | Phil Plait
Bad Astronomy | 28JAN13

    For a while, on the blog, I posted a picture of a gorgeous galaxy every Monday. It was mostly just coincidence, but fun to keep up for a while.

    I may have to start it up again. I’m seeing so many amazingly beautiful galaxy pictures that I just have to share them. And I can’t think of a better way to start off than with one of my favorite objects in the whole sky: M51, the Whirlpool Galaxy:

    Image
    ^ Image credit: vdHoeven/NASA/JPL-Caltech/R. Kennicutt (Univ. of Arizona)/DSS
    Based on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESA) and the Canadian Astronomy Data Centre (CADC/NRC/CSA).


    It’s not too hard to see how it got its name, is it? This picture is actually a combination of two separate space telescope images: Hubble and Spitzer, combined by the wonderful astrophotograper André van der Hoeven. The full-res version is 4000 x 2700 pixels, and nothing short of magnificent. The Hubble shot was taken in 2005, and has a total exposure time of an astonishing nine hours. It was taken in visible light, the kind we see, using filters that accentuate starlight and the gas clouds dotting the spiral arms.

    Image
    ^ Image credti: NASA/JPL-Caltech/
    R. Kennicutt (Univ. of Arizona)
    The Spitzer image (inset here) is in the infrared, well outside what the human eye can see. The picture uses false color, meaning near-infrared shorter wavelength light is colored blue and green, and longer wavelengths are depicted as red. Because of that, dust—complex molecules that absorb visible light but glow warmly at long infrared wavelengths—looks red in the picture. In the original Hubble picture, the dust is dark, seen as brownish-black cottony structures that wind along with the spiral arms. Stars give off shorter-wavelength light in infrared, so they appear colored blue-green in the Spitzer image.

    M51 is actually two galaxies (formally NGC 5194 and 5195), lying about 25 million light years away. The line-up between them is no coincidence: They are physically interacting, going through a complicated collision process. The companion, as it’s called, is a blobby collection of a few billion stars, far smaller than the spiral galaxy, which has well over a hundred billion stars. The companion’s red color in visible light means it hasn’t formed stars in a long time—blue stars are hot and massive, living their entire lives in just a few million years. When they’re gone, only redder stars are around.

    The spiral, though, is quite blue, meaning it’s vigorously forming stars. The pink clumps are star-forming gas clouds, and M51 is loaded with them (note how the dust follows closely; it’s created in part where stars are born). In fact, the spiral structure is particularly strong in the galaxy, more so than usual in spirals galaxies. It’s thought that the companion collided with and passed through the disk of the spiral galaxy, disrupting it gravitationally and exciting all that star formation, which would strengthen the spiral structure as well.

    This collision is not yet over. The first pass happened roughly a half billion years ago, but the gravity of the bigger galaxy held it in thrall. It came from behind, passed toward us through the disk, then swung back down and slammed through it again. Now we see it behind the bigger galaxy, as you can tell from the silhouette of the spiral’s dusty arm in front of the companion. My guess is they will eventually merge into one galaxy, but not for many millions of years.

    It amazes me how much we can tell by simply looking at objects. Combining images like this helps a lot as well, since it accentuates different structures and makes it easier for our eyes to pick see them. We now have a pretty good picture of how galaxies form, how they change over time, what happens when they collide, how they behave during and after they merge. And all this unfolds over timescales of billions of years, sometimes longer than even the age of the Earth itself. When we look out into space we look back in time to all different eras of the past, and, like the pictures we take, those can be combined into a more complete picture of our Universe.
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Re: The scale of things

Postby Wombaticus Rex » Tue Jan 29, 2013 11:20 am

Via: http://theautomaticearth.com/Finance/scale-matters.html

Scale matters. When it changes, other things change as a function of it, often in unpredictable ways. Emergent properties are system characteristics that come into existence as a result of small and simple units of organization being combined to form large and complex multi-unit organizational structures. One can know everything there is to know about the original simple units and yet be unable to predict the characteristics of the larger system that emerges as many units come together to interact as a larger whole.

For instance, knowing everything about an individual cell sheds no light on the behaviour of a sophisticated multicellular organism. At a higher level of organization, knowing everything about an organism does not predict crowd behaviour, the functioning of an ecosystem, the organization of stratified societies, or the dynamics of geopolitics as societies interact with one another. The complex whole is always far more than just the sum of its parts.

Human social organization is particularly flexible when it comes to changes in scale. It can function in a myriad forms - from simple, generalist tribal associations, where everyone knows everyone else and interactions are grounded in established personal relationships, to the most complex, specialized and hierarchical imperial civilizations, where emergent connections and institutional structures must inevitably transcend the personal.

Where human societies find themselves along that continuum will depend on many local factors, including the nature, extent, accessibility and storability of the resource base over time, as well as the potential for leveraging human labour, historically using animals. Energy, and particularly energy returned on energy invested (ie the potential to control substantial energy surpluses) is critical. The greater the extent to which substantial, storable resource surpluses can be amassed and centrally controlled, the more likely a complex hierarchical organizational structure is to emerge. Where surpluses are small, resources cannot be stored, human efforts cannot be leveraged, or key resources are less subject to control, much smaller scale, simpler and more horizontally structured groups would be expected instead.


Forms of organization based on agriculture are inherently both expansionist and catabolic. Existing ecosystems are destroyed to make way for patches of monocrop, rapidly converting the productive potential of the land into human biomass at the expense of biodiversity and soil fertility. Many hands are needed to work the land, so many children are produced, but as they grow up, more land must be cultivated every generation, because the existing land cannot accommodate the rapidly rising number of mouths to feed. Carrying capacity is, however, limited.

This in-built need to expand, sometimes to the scale of an imperium in the search for new territory, means that the process is grounded in ponzi dynamics. Expansion stops when no new territories can be subsumed, and contraction will follow as the society consumes its internal natural capital. Previous agricultural societies have left desert in their wake when that natural capital has been exhausted.

Limits to growth are not a new phenomenon, nor is collapse when expansion is no longer possible. The difference this time is that we are approaching hard limits at a global scale, there is nowhere left to expand to, modernity has greatly increased the scope and the rate of our catabolic potential, and therefore the collapse will be the most widespread human civilization has faced.

Some societies are more despotic than others. Elite control over resources, distribution of surpluses, or monolithic infrastructure, such as major dams, confers power and strengthens hierarchy. Where surpluses are substantial, controllable and storable, and can support a large percentage of the population not required to work the land directly, a great deal of societal differentiation and complexity may develop, with a substantial gap between haves and have nots. The haves are typically part of the rentier economy, or otherwise in a position to cream off the surpluses from the labour of lower social strata.

The degree of general freedom probably depends on the extent to which it is in the interests of the powerful. If it is more profitable for the elite to grant economic freedom, and then reap a large share of the proceeds, than to control society directly from the centre, then freedom is far more likely. When circumstances change, however, that may no longer be the case. Relative freedom is associated with economic boom times, when there is an explosion of economic activity to feed off. When boom turns to bust, and there is little economic activity for a prolonged period, direct control of what if left is likely to be of greater appeal. As we stand on the verge of a very substantial economic contraction, this is a major concern. Freedom is addictive, and taking it away has consequences for the fabric of society.

In our own modern situation, the freedom enjoyed in first world countries is arguably both a direct and an indirect a result of the enormous energy surplus we have benefited from. Energy surplus has allowed us to substitute energy slaves directly for the forced labour that has been a prevalent feature of so many previous societies, and it has allowed us to intensify complexity in order to create many opportunities for innovation and advantage. It has also enabled an increase of scale to the global level, so that hard work for low pay, and unpleasant externalities, could be off-shored while retaining the benefits in the first world, albeit very unevenly distributed within it.

The size of the global energy surplus is likely to fall very substantially in the coming years. This will inevitably have a major impact on global socioeconomic dynamics, as it will undermine the ability to maintain both the scale and degree of complexity of the global economy. The expansion of effective organizational scale on the way up is a relatively smooth progression of intensification and developing complexity, but the same cannot be said for its contraction. As we scaled up we built structural dependencies on the range of affordable inputs available to us, on the physical infrastructure we built to exploit them, on the trading relationships formed through comparative advantage, and on the large scale institutional framework to manage it all. Scaling down will mean huge dislocation as these dependencies must give way. There is simply no smooth, managed way to achieve this.



A foundational ingredient in determining effective organizational scale is trust - the glue holding societies together. At small scale, trust is personal, and group acceptance is limited to those who are known well enough to be trusted. For societies to scale up, trust must transcend the personal and be grounded instead in an institutional framework governing interactions between individuals, between the people and different polities, between different layers of governance (municipal, provincial, regional, national), and between states on the international stage.

This institutional framework takes time to scale up and relies on public trust for its political legitimacy. That trust depends on the general perception that the function of the governing institutions serves the public good, and that the rules are sufficiently transparent and predictably applied to all. This is the definition of the rule of law. Of course the ideal does not exist, but better and worse approximations do at each scale in question.

Over time, the trust horizon has waxed and waned in tandem with large cycles of socioeconomic advance and retreat. Trust builds during expansionary times, conferring political legitimacy on larger scale forms of organization. Trust takes a long time to build, however, and much less time to destroy. The retreat of the trust horizon in contractionary times can be very rapid, and as trust is withdrawn from governing institutions, so is political legitimacy. This process is already underway, as a litany of abuses of public trust previously obscured by expansion is coming to light. Contraction will rapidly lift the veil from far more trust-destroying scandals than almost anyone anticipates.

Even at the peak of expansion, international scale institutions struggled to achieve popular legitimacy, due to the obvious democratic deficit, lack of transparency, lack of accountability and insensitivity to local concerns. Even under the most favourable circumstances, true internationalism appears to be a bridge too far from a trust perspective. For this reason, world government and a global currency were never a realistic prospect, as much as some may have craved and others dreaded them. Even a transnational European single currency has suffered from a fatal disparity between the national level of primary loyalty and the international level of currency governance, and as such has no future.

As the circumstances supporting economic globalization and attempts at global governance evaporate, and the process goes into reverse, smaller and smaller scale governance structures are likely to join international institutions as stranded assets from a trust perspective - beyond the trust horizon - and lose legitimacy as a result. International structures are likely to fade away, or be torn apart by strife between disparate members who no longer see themselves are part of a larger whole. The socioeconomic impact of the latter process, for which Europe is the prime example, is likely to be enormous. For a time this may strengthen national institutions, but this is likely to be temporary as they too are subject to being undermined by the withdrawal of trust.

Where people no longer internalize and follow rules, because they no longer see those rules as in the general interest, existing national institutions would have to devote far more energy to surveillance and compliance enforcement. The difference in effort required is very significant, and that effort further alienates the governed population in a socially polarizing downward spiral of positive feedback. It also renders governance far less effective. The form of the institutional framework may still appear outwardly the same, but the function can be both undermined from below and overwhelmed from within by an obsession with enforcement until it ceases to be meaningful. This shift is already well underway.



As contraction picks up momentum, the combination, on the one hand, of a desire to control remaining resources and the benefits from remaining economic activity, and on the other the loss of trust and compliance, and consequent movement towards enforcement, is likely to lead to far more authoritarian forms of government in many places. While central control can occasionally facilitate useful responses to crisis, such as rationing of scarce resources, the power is far more likely to be abused for the benefit of the few, as has so often been the case throughout history.

It is within this general context that society will have to function, although considerable path-dependent local variation can be expected. Trust has a very long way to withdraw, especially in places where some form of totalitarianism develops, as this malignant form of governance actively undermines trust among the populace for the purpose of maintaining control through fear. Even in luckier locations, trust is likely to contract enough to undermine the efficacy of any institution beyond municipal scale, and possibly smaller.

Contractions as large as the one ahead lead to a major trust bottleneck through which society must pass before any kind of recovery can begin to get traction, but the narrowness of that bottleneck will vary considerably between societies. Societies with well developed, close-knit communities are likely to find that far more trust survives, and that in turn will mitigate the impact of contraction and hasten the recovery that will involve rebuilding trust from the bottom up.

Given that trust is a major determinant of effective organizational scale, and that the trust horizon is set to contract substantially, the scale at which it makes most sense to work will be much smaller and more local than previously. The future will, eventually, be one of decentralization by necessity. The odds of making a positive impact at smaller scale will be substantially higher, particularly if the actions undertaken are predicated upon a simpler society rather than based on current complex systems. It makes sense to focus scarce resources - money, energy, materials, effort, emotional intensity - where they can achieve the most. An understanding of scale and its determinants is critical in this regard.

It is interesting to look at the role of money in relation to trust and societal scale. Very small and simple societies grounded in personal relationships can function on a gift basis, as the high level of trust in a small number of well-known others is enough to mean that keeping track of favours done for one another is not necessary. Favours may simply be performed when necessary and reciprocity taken for granted. Resources may be 'owned' by the group, or made generally available to the group, rather than owned privately and subject to specific exchange.



Scaling up from this point requires interacting with people less well known, where there is less faith that favours done will be reciprocated, so that keeping track becomes necessary. Larger societies are more likely to be hierarchical, with resources privately owned. Exchange of goods or services would then require some form of relative value quantification. It could be decided that everyone's time is of equivalent worth and therefore that, at the simplest level of value accounting, keeping track of hours contributed would be sufficient. Further scaling up would require greater sophistication in both time and resource accounting. Money is the value abstraction that evolves to perform this function, hence the development of a monetary economy is an emergent property of scale. The paradox of money is that even as it allows trust to scale up beyond the personal, its use is fundamentally a measure of distrust in reliable interpersonal reciprocity.

As scaling up continues, along with increasing socioeconomic differentiation, it becomes necessary to interact constantly with completely unknown individuals. For this to function, the necessary trust must vest in the institutional framework itself, in the abstract representation of value that becomes a store of value in its own right in addition to being a medium of exchange, and in the complex web of rules by which it operates in large scale societies. These rules grow progressively more complex with expanding societal scale and increasing complexity, as the nature of money itself becomes increasingly abstract and derivative.

Money in the form of precious metals was replaced by promissory notes based on precious metals, then promissory notes backed by faith alone, virtual representations of promissory notes, promises to repay promissory notes, or bets on the abstract price movements (denominated in promissory notes) of underlying assets, which could themselves by abstract. Trust in the value of these abstractions in turn gives them value, and each extension of monetary equivalence creates the foundation of confidence for the next step.

The initial physical monetary commodity would have been chosen to be relatively scarce and not creatable, facilitating central control over a limited money supply. However, when an expansionary dynamic is underway, and a larger money supply is called for in order to lubricate the engine of a growing economy, a rapidly expanding supply of increasingly abstract monetary equivalents may serve that need, at the cost of the loss of any semblance of control over the supply of what is accepted as constituting money. In other words, inflationary times are grounded in an exponentially exploding supply of human promises, backed by assets that are increasingly over-pledged as collateral even as their price is bid up by the expanding purchasing power granted by confidence in promises to repay. This is another self-reinforcing dynamic.

Our history has experienced many credit-fuelled cycles of expansion, going back to antiquity. Positive feedback spirals continue, relatively smoothly, until they can no longer do so. A limit is reached, and there is typically a rapidly spreading realization that the pile of human promises is very heavily under-collateralized. The trust which had conferred value in abstract promises dissipates very quickly, taking the erstwhile value with it.

The credit which had gained monetary equivalence during the expansion is deprived of it, and the resulting abrupt contraction of the effective money supply becomes a major factor in a positive feedback loop in the deflationary direction - the collapse of the money supply removes the lubricant from the engine of the economy, the fall in purchasing power undermines asset prices and promises consequently become even less well collateralized, driving further contraction.

The last thirty years have seen the latest incarnation of a major expansion cycle, reaching unprecedented heights in terms of trust in the value of abstractions as the exponential growth of the shadow banking system has overwhelmed official monetary channels and control mechanisms. We are now on the verge of the implosion that will inevitably follow as trust evaporates and virtual value disappears. The contraction will proceed until the small amount of remaining credit/debt is acceptably collateralized to the few remaining creditors.

At that point we can begin to rebuild trust in a new monetary system, and by extension a new form of societal organization. It will likely be one with a strong emphasis on central monetary supply control, with little or not scope for the monetization of expansionary promises. The successive 'financial innovations' that built the bubble will be outlawed, as similar phenomena have been before in the aftermath of collapse. Unfortunately, the controls do not last, and a new generation will eventually make similar mistakes once the experience of boom and bust passes once again from living memory.

While there is nothing we can do to prevent the bubble from bursting, or the contraction of the trust horizon that will inevitably occur, we can attempt to cushion the blow and limit the extent of contraction. Understanding the critical role of trust, how to nurture it, how it determines effective organizational scale, and therefore what scale to operate at at what time will allow us to maximize the effectiveness of our actions. In terms of rebuilding a monetary system, it will be necessary in many places to operate at a profoundly local level initially, with the reintroduction of the simplest forms of trust extension above a gift economy - keeping track of hours traded in a time banking process, and local currencies operating within the trust horizon. It will be necessary to build community interconnections actively in order to establish, maintain and increase the necessary trust.

If the process succeeds in halting and reversing the contraction of the trust horizon in places, then new monetary arrangements can be scaled up in those locations when necessary. There will be no need to do so rapidly, as the artificial demand stimulation of the bubble years will have disappeared, inevitably leaving much less economic activity during a period of economic depression, and therefore much less demand for a large money supply to lubricate the engine of the economy.



Governance arrangements operating at a scale in line with local monetary provision will be necessary, and can expect to be more effective than larger institutions substantially beyond the trust horizon. The latter, where they still exist and can exercise power at a distance, are most likely to make it more difficult for society to be able to function rather than less, as they can be expected to resist the decentralization that could allow localities to establish resilience.

Operating at a local scale to build local supply chains and resilience is far more compatible with the human psyche. At times when social organization has expanded to the point where it dwarfs individual actions, and may control them either directly or indirectly, individuals are disempowered by scale. Many feel they have no control over the critical factors of their own lives, which often leads to psychological disturbances such as depression, at present widely addressed with medication. Increasing scale can reduce both empowerment and civic engagement, as it fosters the perception that one can achieve nothing through individual action.

The increasing complexity that accompanies scaling up also occupies time, money and individual energies, leaving little in the way of personal resources to contribute to the public sphere. Of course for the few in positions of control, scale translates into leveraging power, which can effectively become a drug in its own right, but for the masses it is much less conducive to functioning effectively and meaningfully. For a while the masses can be bought off with bread and circuses, and, for some, with aspirations to achieving a position of power and leverage themselves.

This only works while it remains possible to supply sufficient bread and circuses, and while people still believe that higher aspirations may be realistic. Expansions do shake up up established orders enough to open doors for a few to exploit the new niches that open up with increasing complexity, but in the latter stages of expansion, the social strata typically reform and solidify again, so that upward mobility becomes harder or impossible. The combination creates a dangerous situation, where financial implosion and social explosion can happen in a simultaneous dislocation.

The shift to operating at a local scale, over the longer term at least (once the dust has settled), can be expected to improve the balance between individuals and society, albeit at the cost of living in a much simpler, lower energy and less resource intensive manner. The implications of this shift are huge. Almost every aspect of our lives will change profoundly. We can expect the transition to be traumatic, as the dislocation of major contractions has always been. What large scale and extreme complexity have given us only appear to be normal, as they have persisted for much or all of our lifetimes. In fact we stand at the peak of an unprecedentedly abnormal period in human history - the largest in a long series of financial bubbles, thanks to the hydrocarbons that allowed it to develop over decades.

Things look good at the peak of a bubble, as if we could extrapolate past trends forward indefinitely and reach even higher heights. However, the trend is changing as the enabling circumstances are crumbling, and the bubble is already bursting as a result. Our task now is to navigate a changing reality. We cannot change the waves of expansion and contraction, as their scale is beyond human control, but we can learn to surf.
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Trust the Scales of Things to Change?

Postby Allegro » Wed Jan 30, 2013 10:37 pm

^^^ Thank You, Wombaticus Rex!

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The Cold, Dusty Arms of Andromeda

Postby Allegro » Wed Jan 30, 2013 11:08 pm

Highlights mine. Links in original.

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The Cold, Dusty Arms of Andromeda | Phil Plait
Bad Astronomy | Wednesday, 30JAN13

    I know I just posted an image of a nearby spiral galaxy that combines optical and infrared light. But by coincidence another picture just came out, and it shows the far more famous Andromeda Galaxy, and it’s a jaw-dropper:

    Image
    ^ Image credit: ESA/Herschel/PACS & SPIRE Consortium, O. Krause, HSC, H. Linz

    Yegads. And yeah, you want to see this in all its full-res glory. This was taken by the European Herschel observatory, which sees in the far-infrared. Like, really far: What’s shown here as blue is actually IR light with a wavelength of 70 microns, a hundred times the reddest light our eyes can see; green is 100 microns, and red is a combination of 160 and 250 microns. The wavelength of light an object emits corresponds to its temperature, so the material you see as red in this image is at a frigid -261°C (-439F). The warmest material you see in the picture is at -232°C (-385°F). To give you an idea of how cold that is, at that temperature the oxygen in our air would be frozen as hard as rock.

    Andromeda is a spiral galaxy much like our own Milky Way, though physically bigger. It’s also the closest spiral to us, so it’s intensely studied. Unfortunately, it’s tilted with respect to us by only about 13°, so it’s nearly edge-on. That makes it hard to study, because a lot of the material in the front of the galaxy blocks what’s behind it.

    Image
    ^ Side by side view of an optical and IR view of Andromeda. Visible light (left) and combined visible+infrared (right) views of Andromeda. Image credit: Infrared: ESA/Herschel/PACS/SPIRE/J. Fritz, U. Gent; Optical: R. Gendler

    But that’s when you look with an optical telescope. What astronomers call dust is made of lots of different molecules, and is opaque to the light we see. But that cold dust glows in the infrared, so using Herschel allows us to see all of it. Most of the dust, as expected, follows the spiral pattern of the galaxy. Since dust is created when stars are born and when they die—and this happens in the spiral arms for the most part—that’s where the dust is too.

    But also revealed in this image is a large ring of dust (the brightest ring in the image) about 75,000 light years in radius. That may have been formed when Andromeda collided and merged with a smaller galaxy; Andromeda stripped that ill-fated galaxy of its dust, which settled into that ring shape. There are several rings of dust in the picture, so if the merger idea is correct it means Andromeda has been pretty hungry over the past few hundred million years.

    Image
    ^ Image credit: ESA/Herschel/PACS
    & SPIRE Consortium, O. Krause,
    HSC, H. Linz
    A far-infrared image of Andromeda by Herschel was released a couple of years ago, but this one has higher-resolution, and also includes the warmer dust (shown in blue and green) in the galaxy’s heart. As you can see, this dust still traces the spiral pattern, all the way down to the very core of the galaxy. Things get a little messy, though, with the pattern getting a bit chaotic. That’s not too surprising: Hubble observations show that the very center of Andromeda has a lot going on; there was a burst of star formation a couple of hundred million years ago, and there are packs of stars circling the core. Also, every big galaxy has a supermassive black hole at its very center, and Andromeda is no exception: The monster there has a mass at least 30 million times that of our Sun, and may be as much as 100 million times as massive. That’s at least ten times the mass of the corresponding black hole in the center of the Milky Way.

    The Andromeda Galaxy is about 2.5 million light years away, but so huge that it’s visible to the naked eye (as I write this, in January, it’s in the southwest just after sunset for Northern Hemisphere observers), though binoculars are probably needed in even mildly light-polluted skies. I have seen this galaxy myself literally hundreds of times through all manners of optical instruments, so images like this really appeal to me; I love seeing something old as if it’s new again.
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Stardust | Postpanic : The scale of things

Postby Allegro » Mon Feb 04, 2013 2:01 am

If you wish, listen closely by cupping your palms around the backs of the ears, and from a comfortable distance from your speakers, I hope you’d hear all the sounds in this video. The production is quite nice, I think, and elaborately textured, comparatively speaking. No single sound, instrument, voice, or phrase of music dominates the balance of the piece until certain elements must be heard over the others before fading into the balance of the whole; even percussive instruments are balanced within the entirety of the piece, which is pretty important from where I sit.

Personally, another way to say it is there are no sounds or sounds of music that distract from contemplating the message.

As to the scale of things, that resides in our imaginations unless, of course, you’ve been or are an astronaut, then memories of one’s work in space become extraordinarily unimaginable for the rest of us. I love this video, and I’ve highlighted some text in the vimeo notes.


^ Stardust | Postpanic

    VIMEO NOTES. PostPanic director Mischa Rozema’s new short film, Stardust, is a story about Voyager 1 (the unmanned spacecraft launched in 1977 to explore the outer solar system). The probe is the furthest man-made object from the sun and witnesses unimaginable beauty and destruction. The film was triggered by the death of Dutch graphic designer Arjan Groot, who died aged 39 on 16th July 2011 from cancer.

    The entire team at PostPanic (the Amsterdam-based creative company) pushed themselves in their own creative post techniques to produce a primarily CG short film crafted with love.

    The film’s story centers on the idea that in the grand scheme of the universe, nothing is ever wasted and it finds comfort in us all essentially being Stardust ourselves. Voyager represents the memories of our loved ones and lives that will never disappear.

    From a creative standpoint, Rozema wanted to explore our preconceived perceptions of how the universe appears which are fed to us by existing imagery from sources such NASA or even sci-fi films. By creating a generated universe, Rozema was able to take his own ‘camera’ to other angles and places within the cosmos.

    Objects and experiences we are visually familiar with are looked at from a different point of view. For example, standing on the surface of the sun looking upwards or witnessing the death and birth of a star - not at all scientifically correct but instead a purely artistic interpretation of such events.

    Rozema says, ‘I wanted to show the universe as a beautiful but also destructive place. It’s somewhere we all have to find our place within. As a director, making Stardust was a very personal experience but it’s not intended to be a personal film and I would want people to attach their own meanings to the film so that they can also find comfort based on their own histories and lives.’

    Rozema turned to his regular audio partner, Guy Amitai, to create the music for the film. ‘I approached Guy to make the music because I trust him and knew he would instinctively understand what I wanted to communicate with this film.’ Their long-term collaboration over the years helped them explore different musical approaches before finally settling on a musical journey featuring analogue instruments. Amitai explains, ‘Once we started working on this project and I told people about Stardust and what Arjan meant to us all, the offers started pouring in. Musician friends and friends-of-friends all wanting to join in and record even the smallest parts. It was an incredibly emotional and personal journey for us all - not something you can professionally detach yourself from.’

    Credits:
    . A PostPanic Production
    . Written & directed by Mischa Rozema
    . Produced by Jules Tervoort
    . VFX Supervisor: Ivor Goldberg
    . Associate VFX Supervisor: Chris Staves
    . Senior digital artists: Matthijs Joor, Jeroen Aerts
    . Digital artists: Marti Pujol, Silke Finger, Mariusz Kolodziejczak, Dieuwer Feldbrugge, Cara To, Jurriën Boogert
    . Camera & edit: Mischa Rozema
    . Production: Ania Markham, Annejes van Liempd

    Audio by Pivot Audio, Guy Amitai
    Featuring “Helio” by Ruben Samama

    copyright 2013 Post Panic BV, All rights reserved
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NGC 1309: Stepping Stone to the Universe | The scale of thin

Postby Allegro » Mon Feb 04, 2013 9:43 pm

Highlights mine. Links in original.

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NGC 1309: Stepping Stone to the Universe | Phil Plait
Bad Astronomy | Monday, 04FEB13

Image
^ Image credit: NASA, ESA, The Hubble Heritage Team, (STScI/AURA) and A. Riess (STScI)

    This week’s Monday Galaxy was something of a surprise for me.

    When I find a beautiful Hubble picture of a galaxy with which I’m not familiar, the first thing I do is hit the journals and databases. How far away is it? Why was it observed?

    That first one was easy: This galaxy, called NGC 1309, is about 90 million light years away, give or take, putting it at the far side of what we might call “nearby”. Still with Hubble’s incredible vision, NGC 1309 is displayed in amazing detail (grab the 2400 x 3200 pixel version to see for yourself).

    The answer to the second question, at first, eluded me. I dove right into the professional journals and extragalactic databases, looking to see what was going on with this galaxy. I found nothing. No mention of a huge black hole gobbling down matter and blasting out jets, no recent merger with another galaxy, no anomalously bright high-energy sources in it.

    Then I laughed. I realized I didn’t actually read the synopsis of the observation on the Hubble website; I jumped right into the deep end. But when I read the short description, it became clear why NGC 1309 was targeted: It turns out, while overall the galaxy itself is scientifically unremarkable, it’s what’s in it that makes it special.

    NGC 1309 has quite a few stars in it that are called Cepheid variables. These are massive, bright stars that pulsate in brightness on a regular schedule lasting a few days to months. The pulsation period of a Cepheid depends on the absolute brightness of the star, how much energy it emits. By measuring how bright the star appears over time, then, we can determine how bright the star actually is. That in turn allows us to measure its distance (because stars dim with distance in a relatively easy-to-determine way). Since we can see Cepheids in distant galaxies, that allows us to measure the actual distance to these galaxies.

    That fact, all by itself, is amazing.

    But NGC 1309 has another trick up its arm. On top of the Cepheids, in 2002 an exploding star was spotted in the galaxy, and it was of the kind that can also be calibrated to calculate its distance. This kind of supernova is used to measure the distances of galaxies that are incredibly far away, billions of light years distant, clear to the edge of the observable Universe. Being able to find a galaxy with both Cepheid stars and this type of supernova is a rare chance to match the two scales up and make sure they fit. It helps us bootstrap the size and behavior of the entire Universe.

    Incredible.

    Resume.
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M106 Galaxy Zapped by Its Own Black Hole | The scale of thin

Postby Allegro » Wed Feb 06, 2013 1:14 am

Highlights mine. Links in original.

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Galaxy Zapped by Its Own Black Hole | Phil Plait

Bad Astronomy | Tuesday, 05FEB13

Image
^ Image credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), and R. Gendler (for the Hubble Heritage Team)

    Our Milky Way is a pretty nice place to live. It has the same dangers as any large galaxy—black holes, supernovae, the odd gamma-ray burst or two—but they seem relatively mild compared to some other galaxies.

    Especially when you look at the nearby spiral galaxy M 106. If you lived there, you’d be in danger of getting zapped by a cosmic death ray thousands of light years long!

    At first, you might be overcome by the beauty of this photo. I wouldn’t blame you. It’s primarily made of images taken of M106 by the Hubble Space Telescope, but combined with images and data taken by the amazing astrophotographers Robert Gendler and Jay GaBany using ground-based telescopes.

    You can see the yellowish glow of older stars in the center of the galaxy, making up its central bulge, or “hub”. Cascading out are two lovely spiral arms, glowing blue due to the fierce combined light of millions upon millions of hot, young, massive stars. Festooned across the arms are long strings of opaque dust clouds, blocking the blue light and appearing dark. So far, though spectacular, this is pretty mainstream spiral galaxy stuff.

    Then you see those red frills, streamers of gas at odd angles to the rest of the galaxy, one each on opposite sides of the galaxy’s core. These are called its anomalous arms, because they don’t line up well at all with M106’s more obvious spiral arms. The red color is a giveaway that we’re seeing gas being warmed by an outside source; hydrogen glows at that color when excited. So what’s the engine behind that?

    It turns out, that gas is being zapped by twin blasts of energy coming from material being voraciously consumed by the galaxy’s supermassive central black hole.

    I know. It was cool just writing that sentence.

    Every big galaxy has a supermassive black hole in its core. The Milky Way has one, and it has about 4 million times the mass of the Sun. The black hole at M106’s heart is about 30 million times the mass of our Sun. Besides being heftier it’s also actively feeding, gobbling down material swirling around it (our own galaxy’s black hole is quiescent; that is, not eating anything at the moment). As the matter falls in, it forms a huge flat disk called an accretion disk. Heated to millions of degrees and under the sway of unimaginably strong magnetic fields, some of that material blasts away from the black hole at high speeds, going up and down relative to the plane of the disk.

    In M106, that disk is tipped with respect to the galaxy itself. The jets or beams of matter and energy scream away from the black hole at an angle of about 30° from the galaxy’s plane. That means they encounter material on their way out, slamming into it and heating it up violently
    .

    Image
    ^ Image credit: X-ray: NASA/CXC/Univ. of Maryland/A.S. Wilson et al.; Optical: Palomar Observatory. DSS; IR:NASA/JPL-Caltech; VLA: NRAO/AUI/NSF

    That’s what’s causing the anomalous arms! The gas and dust being rammed by the high-energy beams of material from the galaxy’s core heat up and glow. In the Hubble image they emit a bit of red light due to the prevalent hydrogen. But when you look at M106 using the Spitzer (which sees in infrared) and Chandra (X-rays) space telescopes, the picture is clearer. X-rays are generated in very violent events. In this case, shock waves created when the high-speed material slams into the relatively stationary gas heats that material to well over a million degrees, which then emits X-rays. This super-heated matter in turn heats up material around it, making it glow in infrared, too. That’s no surprise, since the jets blast out X-ray energy at a rate millions of times more luminous than our Sun.

    That’s phenomenal. Active galaxies—ones with supermassive black holes eating matter and blasting out high-energy radiation—are not uncommon, but it’s nice to have one this close so we can study it. M106 is only about 25 million light years away, which is nearby for these sorts of things. Because it’s close we can study it in detail and understand what it’s doing; at greater distances the black hole jets would’ve been harder to distinguish from the galaxy itself. This means the behavior of far more distant galaxies can be understood even if we can’t make out the details; we just have to compare the overall behavior with ones like M106 where we have sharper vision.

    So it’s a boon to astronomy to have M106 handy. But when I look at it, I can feel the hair on the back of my neck stir a bit. Surely some of that is the simple scientific thrill, a frisson of intellectual excitement … but I suspect more than a little is knowing that fearsome forces run rampant in some galaxies, blasting energies out that dwarf our Sun and crush our puny human sense of scale.

    Our Milky Way really is a good place for us to live. Because when we look elsewhere, it becomes clear that there but for the grace of galaxies go we.
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Wreckage of a Solar Eruption | The scale of things

Postby Allegro » Wed Feb 06, 2013 1:51 am

Since I’m too fascinated with processes that cause sunspots and coronal mass ejections, pretend this entire article has been highlighted. Links in original.

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The Roiling, Twisted Wreckage of a Solar Eruption | Phil Plait
Bad Astronomy | Tuesday, 05FEB13

Image
^ Image credit: NASA/SDO

    On Jan. 23, 2013, the Sun decided to lose a little weight. Not much, you understand, just a few pounds here and there. Well, actually, not just a few pounds. More like a few hundred million.

    On that date, and taking about seven hours to complete, a towering arch of solar material blasted off into space. That’s cool enough, but the wreckage it left behind on the Sun is nothing short of awe-inspiring:



    The footage you just saw was from NASA’s Solar Dynamics Observatory, which stares at the Sun 24 hours a day. It has cameras that can see in the far-ultraviolet, where the Sun’s bizarre and complex magnetic fields become apparent. Magnetism rules the surface activity, from sunspots to vast explosions of energy, so these UV observations are critical to understanding the processes.

    In a nutshell, one of the most basic laws of physics is that a moving electric charge generates a magnetic field. The Sun is made of mostly hydrogen and helium, with a few other elements sprinkled in, and deep inside the Sun it’s hot enough to strip the electrons from their parent atoms, creating charged particles (called ions; the ionized gas is called a plasma). Not only that, but the hotter stuff from deeper inside the Sun rises to the surface and cooler material sinks—this is called convection, and it’s the same reason hot air balloons float and a boiling pot of water roils. Because the charged particles are moving, they make magnetic fields.

    The convecting material rises in a huge column a thousand kilometers across (roughly as big as Texas), and carries with it that complex magnetic field. These connect up with the magnetic fields of other cells, creating magnetic chaos. Once they pierce the surface, the magnetic field lines can actually prevent the cooling gas from sinking; it stays near the top, cools, and grows darker than the stuff around it: behold, a sunspot!

    Image
    ^ Image credit: NASA/SDO
    The plasma flows along these magnetic field lines, sometimes arcing up in loops going from sunspot to sunspot, reaching heights of tens of thousands of kilometers. The plasma can also be stretched out into a shallower arch called a prominence, which can be a hundred thousand kilometers long. If the magnetic field lines controlling the prominence get tangled up they can short out, and the material can either fall back to the surface of the Sun, or be launched into space. In the case of the prominence on Jan. 23, the material erupted away when the magnetic field lines snapped, and all those disjointed magnetic field lines reconnected with each other after the explosion, causing that amazing roiling of bright solar material in the aftermath. It looks like a horizontal tornado.

    Incredibly, very little of this could be seen in visible light, the kind our eyes see. But in the ultraviolet, it was all laid out for SDO to capture.

    In fact, the Sun erupted twice that day, both times ejecting huge quantities of plasma into space. These coronal mass ejections, as they’re called, blast billions of tons of subatomic particles away from the Sun, each wave carrying its own magnetic field. If they hit the Earth, they interact with our own magnetic field, producing aurorae. One of the CMEs from Jan. 23 did in fact hit us, and created a mild effect. Sometimes, though, the interaction is huge, and can make the Earth’s magnetic field ring like a bell. This can generate big current of electricity under the Earth’s surface (called geomagnetically induced currents) that can cause power outages. They can also affect satellites, messing up GPS and communications.

    For this reason I’m very glad we have satellites like SDO. The Sun is a star, capable of vast episodes of violent activity that affect us on Earth. It’s a very good thing we’re trying to understand it better.
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The Ghostly Glow of the Sun’s Breath

Postby Allegro » Thu Feb 07, 2013 2:07 am

Highlights mine. Links in original.

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The Ghostly Glow of the Sun’s Breath | Phil Plait
Bad Astronomy | Wednesday, 06FEB13

    The Sun may seem steady and calm to the eye, but in reality it’s anything but. Magnetic fields pierce the surface, barely constraining the dozens of millions of tons of ionized plasma that flow along them. These loops of magnetic force store vast amounts of energy, and if released, can explode with the force of millions of nuclear bombs. And when they do, that matter is hurled into space at speeds hundreds of even thousands of times faster than a rifle bullet.

    Screaming across the solar system, most of that material misses the Earth, such a small target we are. But sometimes the geometry is right, and that debris bears down on us. Slamming into the Earth’s own magnetic field, the interaction focuses the subatomic particles from the Sun to our poles, where they cascade down the geomagnetic field lines into our atmosphere. The atoms and molecules in our air become energized by this gust of solar wind, causing them to glow. And when they do—and you see them above, from space—it looks like this:

    Image
    ^ Image credit: NASA/NOAA/DoD/Jesse Allen & Robert Simmon

    That lovely picture is from the Suomi NPP Earth-observing satellite. It has a camera on board that can see light from visible light out to the infrared, beyond what our eyes can see. It’s very sensitive to this light, able to pick up the faintest glimmer, and it also has very keen vision, able to resolve tiny details.

    The picture shows the aurora australis, the glow of the air over Antarctica, in this case over Queen Maud Land, due south of Africa, on Jul. 15, 2012. This is a huge swath of the Earth; the width of the image is about 2000 km (1200 miles). In reality, the aurora was probably mostly green with hints of red and purple, but in this image the colors weren’t separated as they would be in a color picture; for this shot a green photon counts as much as a red one, and all were added together to map the brightness of the aurora.

    The Moon was a crescent at the time this picture was taken, so really the only ambient light is from the aurora itself. And yet you can see the edge of the ice sheet going more-or-less horizontally across the screen, illuminated solely by the glow (the yellow line marks the coastline of Antarctica, with Antarctica below the line, and the Southern ocean above; the winter ice extends past the coast to the north). The jagged streaks in the aurora are not real; they are due to motion in the lights as the Earth’s magnetic field is buffeted by the solar winds, combined with the motion of the satellite itself as it took the image.

    Suomi NPP is a powerful tool; in the hi-res version of this image you can easily see cracks in the ice and separate floes. The superb camera used here is designed to detect low-level light sources such as the aurorae, airglow, forest fires, and city lights. This can be used to carefully measure the human impact on light levels around the globe, in turn an indicator of our footprint on the planet. We know for rock solid fact that humans have a very large influence on many factors on our planet—climate, water flow, heat exchange, air pollution, and much more—so it is absolutely critical we have a better grasp on what we are doing. Suomi NPP is part of a fleet of satellites that have that as their purpose.
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Re: The scale of things

Postby Allegro » Fri Feb 08, 2013 3:41 am

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