72527453
submission
StartsWithABang writes:
As Slashdot has previously reported, NASA Spaceflight has claimed to have vetted the EM Drive in a vacuum, and found there is still an anomalous thrust/acceleration on the order of 50 microNewtons for the device. While some are claiming this means things like warp drive and 70-day-trips-to-Mars are right on the horizon, it's important to view this from a scientist's point of view. Here's what it will take to turn this from a speculative claim into a robust one.
72526457
submission
StartsWithABang writes:
Imagine you just stared into darkness, collecting every photon of light that came by. What would you wind up seeing? The Hubble Space Telescope has done this many times, creating the Hubble Deep Field first and then the Hubble Ultra Deep Field with upgraded cameras and more time. But most recently, the eXtreme Deep Field has surpassed even that. With double the exposure time in the same region as the Ultra Deep Field, we’ve set the most robust lower limit on the number of galaxies in the Universe, and learned what it will take to find the rest.
72467045
submission
StartsWithABang writes:
While it might seem like there are an endless supply of stars in the Universe, the process that powers each and every one requires fuel to burn. At some point — even though it’s far in the future — that fuel will all be spent, and all we’ll be left with are stellar corpses of various types. But the Universe is full of second chances, and opportunities to bring not only burned-out stars back to life, but to give life to the failed stars-that-never-were. Of all the possibilities out there, what’s going to give rise to the very last light in the Universe? The smart money is on colliding and merging (but not inspiraling) failed stars known as brown dwarfs.
72436507
submission
StartsWithABang writes:
It was an idea made famous by the movie Happy Gilmore, but the physics behind it is actually sound: getting a running start, even a slow one, should theoretically be able to improve your driving distance by about 10% off the tee. But there's a big different between physics-in-theory and physics-and-physiology-in-practice, at least, in many cases. This time, however, they line up beautifully, as a running start really can help your golf game!
72403373
submission
StartsWithABang writes:
There are certain words that simply get people’s hackles raised, shutting off the part of their brain that normally responds to reason and instead results in an emotional response taking over. For some, that word is “theory,” one of the words with the biggest gap between its colloquial and scientific uses. But another such term is “consensus.” You might have grown up believing that doing something yourself is the only way to ensure it gets done correctly. But when it comes to science, not only is that not the case at all, but a scientific consensus isn’t the conclusion, but rather the starting point.
72398673
submission
StartsWithABang writes:
Dark matter is necessary to explain the motions of stars, galaxies and the formation of structure in the Universe, but most surprisingly is how its presence and abundance is essential to the existence of life in the Universe. Without dark matter's extra gravitation, heavy elements created in ultra-massive stars would escape from our galaxy in supernova explosions, preventing the formation of rocky planets, liquid oceans, organic molecules, and even life itself.
72367019
submission
StartsWithABang writes:
Stars are some of the most perfect blackbodies in the Universe, meaning that they absorb practically all of the energy incident upon them. So if one star's light shines on another star, it's almost definitely going to be absorbed by that star. But starlight takes hundred of thousands of years to leave a star's core and exit through the surface, does that mean this incident starlight is subject to the same fate? Not at all, and in fact it lasts only two weeks (at most, typically) before getting re-emitted.
72320791
submission
StartsWithABang writes:
Sure, the Hubble Space Telescope gives us unparalleled views of our Universe. We can even use it – with its near-infrared camera, NICMOS – to view the very center of our galaxy, something completely blocked by dust in visible light. But part of the incredible power of Hubble relies not on anything to do with the spacecraft or the instruments itself, but rather on the fact that Hubble is only one part of NASA’s great observatories program. Combined with Spitzer (mid-and-far IR) and Chandra (X-ray) data, the astrophysics of this truly remarkable region is revealed in unprecedented detail.
72255657
submission
StartsWithABang writes:
The cosmic microwave background is a thing of beauty, as not only does its uniform, cold temperature reveal a hot, dense past that began with the hot Big Bang, but its fluctuations reveal a pattern of overdensities and underdensities in the very early stages of the Universe. It’s fluctuations just like these that give rise to the stars, galaxies, groups and clusters that exist today, as well as the voids in the vast cosmic web. But effects at the surface of last scattering are not the only ones that affect the CMB’s temperature; if we want to make sure we’ve got an accurate map of what the Universe was born with, we have to take everything into account, including the effects of matter as it gravitationally grows and shrinks. As we do exactly this, we find ourselves discovering the causes behind the biggest anomalies in the sky, and it turns out that the standard cosmological model can explain it all.
72246203
submission
StartsWithABang writes:
When you think of the Hubble Space Telescope, perhaps you think of what’s touted as its most major feat of all: peering off into deep, dark space, collecting light, and discovering the plethora of distant galaxies laying billions of light years beyond our own, like the Hubble deep field, ultra deep field or extreme deep field. But thanks to a combination of factors, including gravitational lensing, Hubble has beaten its own record, finding the most distant galaxies of all.
72215135
submission
StartsWithABang writes:
We thought — back in the time after Maxwell — that if we understood gravitation and electromagnetism, we’d understand all the forces in the Universe. But once we started to dive inside the atom, and once we discovered the atomic nucleus, a new puzzle arose. Every atom other than hydrogen has multiple protons (and neutrons) inside of it. Yet if the protons had a positive electric charge and the neutrons had no electric charge, the intense repulsion between like charges should drive all nuclei apart. But clearly that wasn’t what was happening in our Universe; something extra must be holding these nuclei together. That's what the strong force is, and this is how it works.
72178037
submission
StartsWithABang writes:
We’ve come an incredible distance in exploring the Universe. In the span of just a single human lifetime, we’ve gone from speculations about what other worlds in our Solar System might be like, the possibility of planets around other stars and wondering how many galaxies might be in our observable Universe to actual answers about all three of these profound questions. But as far as we’ve come, Earth is still the only planet we know of with life on it, and the only one even capable of habituating us as our home. An inspiring plea from those who've left Earth as to why we should take care of it.
72127985
submission
StartsWithABang writes:
When you look out at the nebulae in the night sky — especially if you’re seeing them with your eye through a telescope for the first time — you might be in for a big surprise. These faint, fuzzy, extended objects are far dimmer, sparser and more cloud-like than almost anyone expects. Yet thanks to some incredible image processing, assigning colors to different wavelengths and adjusting the contrast, we can make out detailed structures beyond what even your aided eye could ever hope to perceive. Here's how the magic happens, and what it teaches us.
72086807
submission
StartsWithABang writes:
The overwhelming scientific conclusion based on the observable evidence is that the Universe is expanding and cooling, having emerged from a hot, dense state in the past. We can extrapolate back to a time before neutral atoms existed, before even nuclei could form, and if we continue the extrapolation all the way back, we arrive at a singularity. Only, that last step isn't necessarily one we can take, and the insistence of many on its existence may be the biggest mistake ever made about the Big Bang.
72084227
submission
StartsWithABang writes:
The Universe is filled with a wide variety of stars, planets, galaxies and other optical phenomenon. Despite the fact that there are no such things as green stars, on rare occasions, galaxies themselves appear to be emitting isolated green wisps into intergalactic space. Since the first such object was discovered eight years ago, this was a hotly debated mystery, one that’s been solved with an unlikely phenomenon: the atomic transitions of ionized oxygen, or the same physics that underlies the aurorae here on Earth!
