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+ - The Physics of the Green Flash

Submitted by StartsWithABang
StartsWithABang (3485481) writes "During sunset, the Sun appears to redden, dim, and eventually sink below the horizon. Every once in a while, a rare phenomenon emerges along with it: a green flash, where a greenish-colored beam of light appears just over the Sun. What causes it? One of the most beautiful natural phenomena our planet has to offer, explained in glorious detail."

+ - There's no such thing as a Supercluster

Submitted by StartsWithABang
StartsWithABang (3485481) writes "You may have just heard that we’ve mapped out our supercluster of galaxies — Laniakea — to unprecedented accuracy, identifying a region 500 million light-years in diameter that’s responsible for our local group’s motion through space. While it's an amazing feat of astronomical mapping and cluster identification, calling a structure like this a “supercluster” implies that, in some way, the galaxies, galactic groups and galaxy clusters that make this up are in some way bound together. But this is in no way the case! Come find out why “superclusters” aren’t so super after all."

+ - The exoplanets that never were

Submitted by StartsWithABang
StartsWithABang (3485481) writes "In 1992, scientists discovered the first planets orbiting a star other than our Sun. The pulsar PSR B1257+12 was discovered to have its own planetary system, and since then, exoplanet discoveries have exploded! But before that, in 1963, decades of research led to the much-anticipated publication and announcement of the first exoplanet discovered: around Barnard's star, the second-closest star system to Earth. Unfortunately, it turned out to be spurious, and that in itself took years to uncover, an amazing story which is only now fully coming to light!"

+ - The Moon is super, but not because of the Supermoon!

Submitted by StartsWithABang
StartsWithABang (3485481) writes "Tonight marks the third-and-final Supermoon of the year, but the physics governing the Moon will be no less super or spectacular all year long. Next month, a total lunar eclipse awaits us, while lunar libration allows us to see up to 59% of the Moon's surface over the course of the month, not a mere 50% like you might expect. What's the physics (and astronomy) governing the Moon? Summer Ash has the entire, comprehensive story."

+ - Restoring salmon to their original habitat... with a cannon!

Submitted by StartsWithABang
StartsWithABang (3485481) writes "Hydroelectric dams are one of the best and oldest sources of green, renewable energy, but — as the Three Gorges Dam in China exemplifies — they often cause a host of environmental and ecological problems and challenges. One of the more interesting ones is how to coax fish upstream in the face of these herculean walls that can often span more than 500 feet in height. While fish ladders might be a solution for some of the smaller dams, they're limited in application and success. Could Whooshh Innovations' Salmon Cannon, a pneumatic tube capable of launching fish up-and-over these dams, finally restore the Columbia River salmon to their original habitats?"

+ - Will our Universe end in a Big Rip?

Submitted by StartsWithABang
StartsWithABang (3485481) writes "Now that dark energy is firmly in place as the dominant source of energy in the Universe, the race is on to figure out exactly what its properties are, and what that will mean for the Universe's fate. If it's truly a cosmological constant, we're in for a Big Freeze, as galaxies expand away from one another faster and faster, leaving only our gravitationally-bound local group behind. But if dark energy changes over time, we might yet see a Big Crunch or the most horrifying of all fates: a Big Rip, where galaxy-by-galaxy, star-by-star and eventually atom-by-atom, everything is torn apart!"

+ - The Ten Brightest Stars in the Sky

Submitted by StartsWithABang
StartsWithABang (3485481) writes "When you think of the most recognizable collections of stars: the Big Dipper, Cassiopeia, the “Teapot” in Sagittarius and the Southern Cross, they might have prominent stars, but none of them crack the top 10 in terms of brightness. Who, then, are the brightest stars in the sky? Come see how many you know, and find what makes them shine so brightly, and why they're not representative of most stars in the Universe!"

+ - What most people get wrong about science

Submitted by StartsWithABang
StartsWithABang (3485481) writes "Convinced that the risks of nuclear power are too great for the world? That air travel is unsafe? That GMOs are poisoning our world and our bodies? That fluoridated drinking water causes long-term harm? That climate change isn't a manmade thing? Or that vaccines cause more harm than good? Unless you're willing to drop your ideology and completely cast it aside, you'll never accept what science says about these issues, and therefore you're preventing us all from making a better world. Cut it out!"

+ - Solving the mystery of ancient stars with too many heavy metals

Submitted by StartsWithABang
StartsWithABang (3485481) writes "When you think about the stars in the sky, it takes some study to realize that the bluest, brightest stars are also the shortest lived. So when we look at a cluster of stars — or any stellar population — we can figure out how old it is by looking at the color and magnitude of the brightest, bluest main-sequence stars that are still alive. In general, the oldest objects are the reddest globular clusters, which formed when the Universe was only a few hundred million years old. Because the Universe was mostly hydrogen and helium at the time, enriched by relatively few generations of stars, these clusters tend to have very small amounts of heavy elements like iron, sometimes as little as 1% of what’s in our Sun. So when a star cluster has a color/magnitude diagram that says it's very old but a heavy element abundance that says it's relatively young, who wins? We all do, by learning more about how, when and where atomic riches accumulate in galaxies!"

+ - How long has the Universe been accelerating?

Submitted by StartsWithABang
StartsWithABang (3485481) writes "Although dark energy has always been present in the Universe, it didn't come to dominate the Universe's energy content until recently. But even before that, its effects on the Universe's expansion rate could be felt, and it caused distant galaxies to begin accelerating away from us. Thanks to the precision measurements that have come out since the Planck satellite, we're now able — for the first time — to pinpoint with tremendous accuracy exactly when the Universe transitioned from a decelerating to an accelerating state. Come have your misconceptions about dark energy and cosmic acceleration cleared up here. (And no, the expansion rate itself isn't increasing; it's still going down!)"

+ - Back to school advice for STEM students

Submitted by StartsWithABang
StartsWithABang (3485481) writes "Labor Day is this coming Monday, and that means the new school year is about to start. Whether you are or whether you know a young person, say in middle-or-high school, you’re likely very close to someone facing a lot of uncertainty about not only their future, but about their present. Who can be expected to know exactly what they want to do and exactly how to get the most out of it when they’re only a teenager? Yet that’s what we expect most students to do. For students that are interested in STEM — science, technology, education and mathematics — the pressure is even greater. So what advice should you give them? Here’s a great start, from someone who’s been there and who’s helped a generation of kids go through it!"

+ - Could Dark Matter just be Normal Stuff that's Dark?

Submitted by StartsWithABang
StartsWithABang (3485481) writes "When you look out into the Universe at distant galaxies, at clusters of galaxies or at the Universe on the largest scales, what you see is the luminous stuff, which is pretty exclusively stars and stellar-related objects. But based on what we know about gravitation on those scales, we know there’s got to be much more mass than that, most of which doesn’t emit light: dark matter. It seems like a great leap to presume that there’s a new type of matter out there accounting for these observations. Could normal, non-luminous matter possibly account for all the dark matter? No, and here’s why it can't!"

+ - Comcast tells government that its data caps aren't actually "data caps"-> 1

Submitted by mpicpp
mpicpp (3454017) writes "Customers must pay more if they exceed limits—but it’s not a cap, Comcast says.

For the past couple of years, Comcast has been trying to convince journalists and the general public that it doesn’t impose any “data caps” on its Internet service.

That’s despite the fact that Comcast in some cities enforces limits on the amount of data customers can use and issues financial penalties for using more than the allotment. Comcast has said this type of billing will probably roll out to its entire national footprint within five years, perhaps alongside a pricier option to buy unlimited data.

“There isn't a cap anymore. We're out of the cap business,” Executive Vice President David Cohen said in May 2012 after dropping a policy that could cut off people's service after they use 250GB in a month. Comcast's then-new approach was touted to "effectively offer unlimited usage of our services because customers will have the ability to buy as much data as they want.""

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+ - Exomoon Detection Technique Greatly Expands List of Potential Habitable Systems

Submitted by Luminary Crush
Luminary Crush (109477) writes "Most of the detected exoplanets thus far have been gas giants which aren't great candidates for life as we know it. However, many of those planets are in fact in the star's habitable zone and could have moons with conditions more favorable. Until now, methods to detect the moons of such gas giants have been elusive, but researchers at the University of Texas, Arlington have discovered a way to detect the interaction of a moon's ionosphere with the parent gas giant from studies of Jupiter's moon Io. The search for 'Pandora' has begun."

+ - The Stars Beyond

Submitted by StartsWithABang
StartsWithABang (3485481) writes "You've no doubt heard of dark matter halos around galaxies: vast, extended, spherical collection of mass that reach for hundreds of thousands of light-years beyond what we typically think of as a spiral or elliptical galaxy. But did you know that galaxies contain vast, extended stellar halos as well? Moreover, they look nothing like you'd expect! They're not spherical or even ellipsoidal, but highly irregular, and have an awful lot to teach us about how galaxies came to be the way they are today."

It is surely a great calamity for a human being to have no obsessions. - Robert Bly