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Where will we all be in 100 billion years?

StartsWithABang Oops (1 comments)

That should read "100 billion years from now", not "100 billion years ago". My typo.

about 3 months ago

Submissions

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Einstein's undefeated record reaches 99 years

StartsWithABang StartsWithABang writes  |  8 hours ago

StartsWithABang (3485481) writes "When it comes to physics, there sure are some strange theories — and even stranger phenomena — out there. The notion that particles don’t have fixed, intrinsic properties that are simultaneously measurable can only be described as weird, and the fact that you can add as much energy as you want to a particle but it will never accelerate to beyond a particular speed is certainly counterintuitive. Yet one theory has them all beat. For ninety-nine years, now, General Relativity has made a whole host of unique predictions, ranging from time slowing down in a gravitational field to the bending of starlight to the decay of pulsar orbits, that have been observationally confirmed each and every time. It's the strangest theory we know to be true, and we're on the brink of testing (and possibly confirming) its predictions to even better precision!"
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Could we abort a manned mission to Mars?

StartsWithABang StartsWithABang writes  |  3 days ago

StartsWithABang (3485481) writes "The next great leap in human spaceflight is a manned mission to a world within our Solar System: most likely Mars. But if something went wrong along the journey — at launch, close to Earth, or en route — whether biological or mechanical, would there be any way to return to Earth? A fun (and sobering) look at what the limits of physics and technology allow at present."
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The entire history of the Universe in ten sentences

StartsWithABang StartsWithABang writes  |  5 days ago

StartsWithABang (3485481) writes "The greatest story ever told is the one the Universe tells us about itself: how it went from a state of empty and expanding spacetime to one containing the huge number of galaxies, stars, planets and atoms, not to mention you. Here is the shortest version of that story ever that is still accurate and comprehensive, with ten sentences covering the entire thing!"
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How to destroy the entire Universe

StartsWithABang StartsWithABang writes  |  5 days ago

StartsWithABang (3485481) writes "For all the aspiring supervillains out there, you may have heard that Stephen Hawking recently wrote about the possibility of the Higgs field destroying the Universe. As it turns out, that's not very likely to happen, not likely to affect us if it does happen, and not something we can control in any case. But there is something we can do if we were intent on destroying the Universe: restore the inflationary state that gave rise to the Universe (and the Big Bang) in the first place!"
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What Astrology got right

StartsWithABang StartsWithABang writes  |  about a week ago

StartsWithABang (3485481) writes "When you think of astrology today, you likely think of someone who makes false promises and proclaims either platitudes or fabrications as though they were preordained truths. That's not even an unfair judgment. For many millennia dating to just a few centuries ago, though, astrology was anything but. Our initial thoughts on the idea that what happens in the heavens affects what happens on Earth may have been flawed, but as it turns out, the simple idea of observing the Universe beyond our own world has been able to teach us more than the ancients would have ever dreamed! A fascinating look at the story of where science itself originated."
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Einstein's Greatest Legacy

StartsWithABang StartsWithABang writes  |  about a week ago

StartsWithABang (3485481) writes "When you think of Einstein — beyond the quotable old guy with the crazy hair — you probably think of trains moving near the speed of light, matter converting into energy (and vice versa), the fabric of space and time or perhaps the equivalence principle. Yet all of these ideas, special and general relativity, E=mc^2 and so on, sprung from the same source, the gedankenexperiment, or thought-experiment. It's amazing what the human mind, all on its own, can accomplish, including knocking on the door of the newest frontiers in science!"
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What's the earliest signal from the Universe?

StartsWithABang StartsWithABang writes  |  about two weeks ago

StartsWithABang (3485481) writes "When we look out into the Universe, we can see fainter and farther than ever before simply by building larger telescopes and having them take longer exposures: in other words, by gathering more light. But even in principle, there's a limit to what we can see, thanks to the fact that, beyond a certain point, the Universe was an ionized plasma, randomizing whatever information was contained in the light passing through it. But that doesn't mean we can't see beyond that point, it just means we can't use light to do it! Gravitational waves are the future of astronomy, and can even tell us how the Universe got its start!"
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Big Bang's Final Prediction Directly Confirmed!

StartsWithABang StartsWithABang writes  |  about two weeks ago

StartsWithABang (3485481) writes "The Big Bang has, among its predictions, three cornerstones: the Hubble Expansion of the Universe, the Cosmic Microwave Background, and the abundance of the Light Elements due to Big Bang Nucleosynthesis. The first one has been confirmed to spectacular accuracy, and with the COBE, WMAP and Planck satellites, the spectrum and fluctuations in the CMB rule out almost every other feasible alternative. But detecting the abundance of the light elements directly has always run into a difficulty: the formation of stars in the Universe pollutes the intergalactic medium, ruining our ability to see anything "pristine." We'd have to get incredibly lucky, to find a region of molecular gas that had never formed stars in-between our line-of-sight to a quasar or bright galaxy. For nearly 70 years, that didn't happen, and then all of a sudden, we found two. The Big Bang stands tall after all!"
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The Physics of the Death Star

StartsWithABang StartsWithABang writes  |  about two weeks ago

StartsWithABang (3485481) writes "Sure, the idea of destroying an entire planet may sound like an unachievable dream of a pathological teenager, as the energy required would be tremendous. To simply overcome the gravitational potential energy binding an Earth-sized planet together would require the entire energy output of the Sun added up over more than a week! But if we could harness a relatively small amount of antimatter — just 0.00000000002% the mass of the planet in question — that would be enough to do it."
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There's no such thing as a Supercluster

StartsWithABang StartsWithABang writes  |  about three weeks ago

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."
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The exoplanets that never were

StartsWithABang StartsWithABang writes  |  about three weeks ago

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

StartsWithABang StartsWithABang writes  |  about three weeks ago

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."
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Restoring salmon to their original habitat... with a cannon!

StartsWithABang StartsWithABang writes  |  about three weeks ago

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?"
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Will our Universe end in a Big Rip?

StartsWithABang StartsWithABang writes  |  about three weeks ago

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!"
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The Ten Brightest Stars in the Sky

StartsWithABang StartsWithABang writes  |  about three weeks ago

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!"
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What most people get wrong about science

StartsWithABang StartsWithABang writes  |  about a month ago

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!"
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Solving the mystery of ancient stars with too many heavy metals

StartsWithABang StartsWithABang writes  |  about a month ago

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!"
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How long has the Universe been accelerating?

StartsWithABang StartsWithABang writes  |  about 1 month ago

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!)"
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Back to school advice for STEM students

StartsWithABang StartsWithABang writes  |  about a month ago

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!"

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