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Submission + - Hubble catches a star cluster lying about its age

StartsWithABang writes: When you look at a globular cluster, you’re seeing a relic from the ancient Universe, where its stars formed back when the Universe was just a few percent of its present age. At least, that’s what you see in general, but a few globulars are much, much younger than that. Hubble has recently photographed a cosmic impostor, NGC 1783, which is only 10% the age of most globulars. Here's the secret of how it got to be that way, and how to catch lying globulars in general.

Submission + - How close are we, really, to nuclear fusion?

StartsWithABang writes: The ultimate dream when it comes to clean, green, safe, abundant energy is nuclear fusion. The same process that powers the core of the Sun could also power everything on Earth millions of times over, if only we could figure out how to reach that breakeven point. Right now, we have three different candidates for doing so: inertial confinement, magnetic confinement, and magnetized target fusion. Recent advances have all three looking promising in various ways, making one wonder why we don't spend more resources towards achieving the holy grail of energy.

Submission + - Stephen Hawking's proposal to solve the information paradox is no solution

StartsWithABang writes: Stephen Hawking is claiming that the black hole information paradox has now been resolved, with the information encoded on the event horizon and then onto the outgoing radiation via a new mechanism that he’ll detail in a paper due out next month, along with collaborators Malcom Perry and Andrew Strominger. Only, that’s not really what’s happening here. While he does have a new idea and there is a paper coming out, its contents do not solve the information paradox, but merely provide a hypothesis as to how it may be solved in the future.

Submission + - Do you really love science enough to recognize hype in headlines?

StartsWithABang writes: When you first venture out into the world, you're armed, as a human being, with an incredible intelligence, but with no experience. All sorts of basic things must be learned, often the hard way: hot things will burn you, hot things that don't look hot will also burn you, and that even very cold things will burn you, too. Figuring those things out — and the process by which you learn them — is science, in and of itself. But to move forward requires that we understand why, and that's where scientific theories, leaps and even revolutions come into play.

Submission + - Has Stephen Hawking solved the black hole information paradox?

StartsWithABang writes: Earlier this week, Stephen Hawking shook up the world when he announced that he had uncovered the solution to the black hole information paradox at a conference in Stockholm. When particles fall into (or create) a black hole, information is encoded on the black hole’s surface, but when the black hole decays into radiation, that information appears to be lost, as the radiation is thermal. But perhaps the information is stored on the event horizon, and can be encoded into the outgoing radiation thanks to the interplay of gravitation and matter. Details should be forthcoming in a paper to be released next month by Hawking, Malcom Perry and Andrew Strominger.

Submission + - How fast we're moving relative to the Universe known for certain

StartsWithABang writes: If you wanted to know how fast you were moving through space, you’d need to measure it all: the Earth’s rotation, our motion around the Sun, the Sun’s motion through the galaxy, the Milky Way’s speed within the local group, and finally how the local group moved relative to the Universe. All in all, it’s a daunting, virtually impossible task without literally measuring everything in the entire Universe itself. Or, you could take advantage of an amazing fact: the leftover glow from the Big Bang exhibits a redshift in one direction and a blueshift in the other. In other words, the cosmic microwave background has a dipole, and that dipole tells us our motion relative to the Universe!

Submission + - Some observers perceive the Universe to be much younger than we do

StartsWithABang writes: It’s been 13.8 billion years since the Big Bang for us, and when we look out at a distant object in the Universe, we’re seeing it as it was in the past. Its age — as it appears — is determined only by how long the light took for it to travel from that object to our eyes, but to someone living there, it will also appear that the Universe is 13.8 billion years old. But it is actually possible for an observer living on another planet, star or galaxy to perceive that significantly less time has passed since the Big Bang, so long as they were moving close to the speed of light relative to the CMB. Paradoxically, if they slowed their speed, they’d find that they themselves were very young, but living in a 13.8 billion year-old Universe.

Submission + - It takes 26 fundamental constants to describe our Universe

StartsWithABang writes: The standard model, gravity, and all the known particles and interactions can be semi-elegantly explained with only 26 parameters, including dark energy and neutrino masses. And yet with these 26 constants, we still don’t get everything: dark matter, the matter-antimatter asymmetry and cosmic inflation may yet dictate that more parameters are required to give us everything our Universe requires. Is there a more fundamental theory out there to describe it all more simply? Or is this simply a messy, inelegant Universe we’re stuck with?

Submission + - It may be impossible to know the origin of our Universe

StartsWithABang writes: If we trace the evolution of our Universe back in time, we can arrive at a time before there were organic molecules, rocky planets, heavy elements, galaxies, stars, or even neutral atoms. The farther back we go, the hotter the Universe gets, the higher in density and temperature, and more uniform. But at some point, this hot, dense, expanding state ceases to describe our Universe. Because preceding it was a period of cosmic inflation: a period of indeterminate duration. It must have lasted at least some 10^-35 seconds, but it could have lasted much, much longer, including the possibility that it was around for an infinite amount of time. But we may never know, because the nature of inflation wipes that information out from our Universe altogether.

Submission + - The most impossible idea from Star Trek is the transporter

StartsWithABang writes: Today would have been the 95th birthday of Gene Roddenberry, the mind that brought us the Universe of Star Trek. In addition to a utopia where maladies like hunger, disease and poverty were eradicated, Star Trek promised a future where technology was widely available and sufficiently advanced to the benefit of all of humanity. While many of these imagined advances in technology have been met or even exceeded already, such as in the field of medical diagnostics and communication, others like warp drive and the Star Trek transporter may never come to fruition. No matter how much your technology advances, you still can’t circumvent the laws of nature.

Submission + - Gravity doesn't always add up

StartsWithABang writes: Every time you follow the motion of a spacecraft, moon, planet or other object through the Solar System, you’re putting the theory of gravity to the test. On one hand, there’s a robust set of predictions for what the behavioral motion of these bodies ought to be, while on the other there’s what we actually observe. Sometimes, a mismatch indicates the need for something new, like a new planet or a new law of gravity. But other times, there are mundane explanations that account for these “apparent” discrepancies, such as radioactive decay, heating from the Sun or the fact that the Earth rotates on its axis. Not all the phenomena of our Solar System have been explained, however, including the flyby anomalies and the changing perigee/apogee difference of the Moon, with compelling indications that new physics may be right around the corner.

Submission + - The Death Star could become a reality with asteroid-sized antimatter chunks

StartsWithABang writes: The ability to destroy an Alderaan-like (or, ahem, Earth-like) planet has long been the dream of slashdotters everywhere. But generating the power necessary to unbind a planet — some 2.24 x 10^32 Joules — is simply impossible on board an object only the size of a small moon. But if, instead, you could house a 1-2 trillion ton asteroid (about 5-7 km across) made of antimatter and deliver it to the planet's core, Einstein's E=mc^2 ensures that the planet will be destroyed in seconds. And now, you will witness the power of this fully armed and operational battle station!

Submission + - If our Universe were slightly less lumpy, we couldn't have existed

StartsWithABang writes: When you visualize our Universe today, you probably think about the great clumps of matter — planets, stars, galaxies and clusters — separated by huge distances. But on the largest of all scales, tens of billions of light years in diameter, any given region of the Universe is virtually indistinguishable from any other. But this structured Universe only came about because our Universe was born with initial fluctuations at the start of the hot Big Bang. Without those fluctuations of a sufficiently large magnitude, no structure would have formed at all before dark energy ruined the possibility of anything happening, ever.

Submission + - Evolution of starlight determined from the moment of star birth

StartsWithABang writes: We like to think of the stars as fixed, as their position doesn’t perceptibly change from night-to-night or even year-to-year. Not only that, but their brightness and color doesn’t appear to change, either. But is that actually true, or is that only because we don’t have the capabilities — as humans — to view these stars on the sufficiently long timescales that they do evolve on? It’s very much the latter, as stars evolve in both color and brightness over time, with their life cycle absolutely predestined from the moment of the star’s birth.

Submission + - Why the Perseids are consistently the year's best meteor shower

StartsWithABang writes: When the debris path of a comet or asteroid crosses Earth's orbit, a meteor shower is the result. Some showers are duds, with the meteors being infrequent, inconsistent, short-lived and dim. Hardly worth mentioning. On the other hand, meteor showers can be spectacular, with frequent events, consistent displays year-to-year, lasting many consecutive nights and with bright, luminous fireballs. The Perseids, peaking tonight, are all four of these things, and we have its unique history and origins to thank for it!

"Floggings will continue until morale improves." -- anonymous flyer being distributed at Exxon USA