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We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).


+ - How would humans die in the vacuum of space?

Submitted by StartsWithABang
StartsWithABang (3485481) writes "In films like Gravity, Mission to Mars and Total Recall, humans are often shown dying rapidly and catastrophically from exposure to the vacuum of space. But are these deaths scientifically accurate? Would you freeze, boil, explode, swell-to-incapacitation or something else? You wouldn't last long during a rapid decompression, but if you could survive the initial switch, you'd actually have 10-to-14 seconds of consciousness, followed by a total of 90 seconds or so to be rescued before death permanently took you."

+ - Earth second almost Moon

Submitted by StartsWithABang
StartsWithABang (3485481) writes "Planets can have not only moons, but gravitationally captured bodies co-orbiting the Sun either ahead or behind them in orbit. Jupiter, for example, has not only all the moons that orbit around it, but thousands of gravitationally captured objects in addition: the Trojans (and Greeks). While Earth may have only one true moon orbiting our world, what of these Trojans? Do we have any captured asteroids or comets hanging out around one of our Lagrange points? We absolutely do, but only one of them is here to stay, and it very likely isn’t the one — 3753 Cruithne — you’ve heard of."

+ - Every star will die, but most will live again

Submitted by StartsWithABang
StartsWithABang (3485481) writes "No matter how well we care for our bodies, they eventually wear down, give out, and we all will someday face death. Yet if there’s anything to be learned from looking at the physical Universe, there’s no reason to expect that death is truly the end. Every time a star runs out of fuel and dies, no matter what type of star it is or what fate it suffers, there’s always a new chance for both new stars and new life to arise from it. From stars resulting in the most massive supernovae to the smallest red dwarfs, the death of these objects is only a single step along a cosmic journey that began long before any stars existed and will continue long after the Universe ceases to resemble what we know today."

+ - What happens when Betelgeuse explodes? 1

Submitted by StartsWithABang
StartsWithABang (3485481) writes "One of the great, catastrophic truths of the Universe is that everything has an expiration date. And this includes every single point of light in the entire sky. The most massive stars will die in a spectacular supernova explosion when their final stage of core fuel runs out. At only an estimated 600 light years distant, Betelgeuse is one (along with Antares) of the closest red supergiants to us, and it’s estimated to have only perhaps 100,000 years until it reaches the end of its life. Here's the story on what we can expect to see (and feel) on Earth when Betelgeuse explodes!"

+ - Non-scientists can't tell the difference between real science and a numbers game

Submitted by StartsWithABang
StartsWithABang (3485481) writes "No one science can stand wholly on its own. For inquiry about the Universe to give a correct, complete picture, it requires that we bring in a whole slew of evidence, often from tangentially related fields. The interplay between three fields in particular — astronomy, physics, and math (not a science, but the tool used to help understand the relationships arising in the first two) — have given rise to the most successful picture of the Universe of all-time. But to the non-scientists out there, it's often difficult to tell a sciencey-sounding idea from real science."

+ - The cause of the Moon's great crater chains

Submitted by StartsWithABang
StartsWithABang (3485481) writes "You might think that your odds of getting 3, 5, or even 10 or more craters all next to each other and in a row on an object like the Moon are astronomically small. Yet, we've identified dozens of features that show exactly this! Here are some of the most spectacular, along with the redux of the leading ideas of where they came from, including secondary impacts, tidally disrupted impactors and volcanic and geologic explanations."

+ - Using the cold to make frozen soap bubbles

Submitted by StartsWithABang
StartsWithABang (3485481) writes "While those of us faced with below-freezing temperatures are already sick of the long, brutal winter, there's a little do-it-yourself beauty coming your way. All it takes is some water, dish soap, and either glycerine or corn syrup, and you're all set to make your own frozen soap bubbles. Here's a great how-to guide, complete with ingredients, conditions and techniques, that showcases the amazing results of three aficionados who've already done it!"

+ - The story of the very early Universe

Submitted by StartsWithABang
StartsWithABang (3485481) writes "Our observable Universe got its start at the hot Big Bang, where every single known particle and antiparticle of matter or radiation existed in great abundance. Normally, the story of what happened to everything as the Universe expanded and cooled is glossed over, picking up with the leftover matter forming nuclei and atoms. Here is a terrific and accessible treatment of all the details that happen in between. Required reading for aficionados of how our Universe came to be the way it is."

+ - The science of a bottomless pit

Submitted by StartsWithABang
StartsWithABang (3485481) writes "It’s the ultimate dream of many children with time on their hands and their first leisurely attempt at digging: to go clear through the Earth to the other side, creating a bottomless pit. Most of us don’t get very far in practice, but in theory, it should be possible to construct one, and consider what would happen to a very clever test subject who took all the proper precautions, and jumped right in. Here's what you would have to do to travel clear through the Earth, come out the other side, and make the return trip to right back where you started."

+ - Don't trust your proofs in theoretical physics

Submitted by StartsWithABang
StartsWithABang (3485481) writes "In mathematics, a theorem will absolutely, definitively settle an issue as to whether something can or cannot happen. But in physics, the waters are a lot murkier. Proofs and theorems of forbidden phenomena (like 21-cm hydrogen emission) abound, and yet those phenomena occur. Similarly, theorems exist that certain events must occur (like the Poincare recurrence theorem), and yet they never will. Beware of what a proof or theorem actually means for the Universe, and keep this in mind when it comes to the origin of space and time itself!"

+ - What's up in the sky this winter?

Submitted by StartsWithABang
StartsWithABang (3485481) writes "They say that a telescope is only as good as the amount of time you spend looking through it, and for most people, that's not nearly as often as they plan. But if you're one of the avid ones, what should you focus on when you're sharing the night sky with another? This tremendous, comprehensive guide covers all the essentials to think about when showcasing the wonders of the Universe with first-timers, from planets to deep-sky objects and more."

+ - Watch Comet 67P/Churyumov-Gerasimenko come to life

Submitted by StartsWithABang
StartsWithABang (3485481) writes "When ESA’s Rosetta mission “caught” its target, Comet 67P/Churyumov-Gerasimenko in August, 2014, one of its main science goals was to watch the comet become active from up close. Half a year later, the flux of particles being emitted by the comet has intensified tremendously, and so it’s now time for Rosetta to move on to the next phase of its mission, flying closer to the comet to observe its next phase of evolution. In the meantime, take a look back, in pictures, at how the comet became active since it was caught by Rosetta."

+ - The Math of Powerball

Submitted by StartsWithABang
StartsWithABang (3485481) writes "This past week, the Powerball Jackpot crested past $500 million, one of the largest Jackpots in lottery history. You might think — since the odds of hitting the Jackpot are “only” 1-in-175,223,510 — that it’s a no-brainer to buy a $2 ticket and take your shot at $500 million. But if you take everything into account, what is the expected value of a Powerball ticket? As it turns out, it’s not only less than you probably think, it’s much less than you ever imagined: topping out at a mere $0.852 for a $2 ticket when you take everything into account. It’s often been said that the lottery is a tax on the mathematically challenged, and now you’ve got the hard, mathematical evidence to back it up!"

+ - How can we still see the leftover glow from the Big Bang?

Submitted by StartsWithABang
StartsWithABang (3485481) writes "When we look back to greater and greater distances in the Universe, we’re looking back to earlier and earlier times as well. At some point, we can see far enough back that we reach the location at which the Universe cooled enough to first form stable, neutral atoms. But this is no nearby location: it’s presently located some 45.3 billion light-years away! All the stars, galaxies, clusters and gas clouds that we see that are closer than that had the leftover light that was released as the cosmic microwave background pass us by ages and ages ago. Here's what it means that the cosmic microwave background — the leftover glow from the Big Bang — is still visible to us today."

+ - How to see a black hole

Submitted by StartsWithABang
StartsWithABang (3485481) writes "The idea of a black hole has been around for hundreds of years: a region of space where there’s so much matter-and-energy that not even light can escape from it. Yet despite this property, the fact that any form of energy that ever enters it is forbidden from leaving, these objects are not invisible. Rather, there are a number of ways they reveal themselves to us practically, as well as theoretically, in ways we may detect in the not-too-distant future."

Vax Vobiscum