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Strange Signal From Galactic Center Is Looking More and More Like Dark Matter

The more that scientists stare at it, the more a strange signal from the center of the Milky Way galaxy appears to be the result of dark matter annihilation. If confirmed, it would be the first direct evidence for dark matter ever seen.

Dark matter is a mysterious, invisible substance making up roughly 85 percent of all matter in the universe. It floats throughout our galaxy, but is more concentrated at its center. There, a dark matter particle can meet another dark matter particle flying through space. If they crash into one another, they will annihilate each other (dark matter is its own antiparticle) and give off gamma rays.

To search for a dark matter signal, astronomers use NASA’s Fermi Gamma-Ray Telescope to map the gamma radiation throughout the galaxy. Then, they try to account for all known sources of light within this map. They plot the location of gas and dust that could be emitting radiation and subtract that signal from their gamma-ray map. Then they determine where all the stars are and subtract out that light, and so on for every object that might be emitting radiation. Once all those sources are gone, there remains a tiny excess of gamma radiation in the data that no known process can account for.

“The more we scrutinize it, the more it looks like dark matter,” said astrophysicist Dan Hooper of Fermi National Accelerator Laboratory, co-author of a paper that appeared Feb. 26 on arXiv, a website that hosts scientific papers that have yet to go through peer-review.


Since 2009, Hooper has been claiming that this bright signal is evidence of dark matter. According to his team’s latest data, the gamma radiation could be produced by dark matter particles with a mass of 30 to 40 gigaelectronvolts (GeV) crashing into one another. A proton is roughly 1 GeV for comparison.

But the galactic center is a tricky place. There are many other gamma ray sources that could be mimicking a dark matter signal as well as yet undiscovered phenomena that might account for the radiation. For the most part, few other researchers have been convinced of Hooper’s data. One oft-used counterargument is that the excess gamma ray signal could come from millisecond pulsars — dead star cores that spin extremely fast and beam out a huge amount of energy. Astronomers don’t yet have a good understanding of how these objects work.

“If you need to explain something weird in the galactic center, you wave your hands and say, ‘Millisecond pulsars,’” said astronomer Doug Finkbeiner of Harvard, another co-author of the new work.

Finkbeiner has long been a skeptic that the excess Fermi telescope signal represents dark matter annihilation. He knows that the galactic center is a strange place full of unexpected phenomena, having discovered in 2010 two gigantic structures spanning 50,000 light-years emanating from the Milky Way, which had gone unnoticed until then. But a more careful look at Hooper’s data has started to convince Finkbeiner that there might be something there.

When a galaxy forms, gravitational attraction brings together a huge mass that begins spinning. As they spin, large galaxies cool down and flatten out like a pizza, forming the familiar spiral shape seen in many telescope images. Dark matter, which actually makes up the bulk of a galaxy’s mass, can’t flatten out because it doesn’t interact with the electromagnetic force, which would allow it to radiate away thermal energy. It stays in a spherical halo circling the galaxy. So any dark matter signal should come not just from within the galactic plane, but also from above and below it, where stars are few and far between but dark matter is abundant.

More here: http://bit.ly/drkmatt
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Sai SK's profile photoUniversum Brasil's profile photoDennis D. McDonald's profile photoErez Odier's profile photo
 
Well, I learned something new: "Dark matter, which actually makes up the bulk of a galaxy’s mass, can’t flatten out because it doesn’t interact with the electromagnetic force, which would allow it to radiate away thermal energy." 
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Spaceship: Earth
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And in multiple dimensions.
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It's nice that Sun does not have a binary companion!
 
Double Star with a planet equals chaos

A planet in a double star system can switch suns.

It can also crash into a sun, or be ejected completely from the system.

#Gravity gets complicated when three bodies are involved, and millions of calculations are required to compute paths like these. I created the animation using a gravity simulation package written by Eugene Butikov of St. Petersburg State University.
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Manoj arunachalam's profile photoGrym Thor's profile photoDan Martin's profile photoKramer McBarrett's profile photo
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Like +Zephyr López Cervilla  just mentioned, what exactly is it that makes that planet swing to the other star? How do you measure it? What makes it unstable when " the binary star system Alpha-Centauri has probably a planet (or perhaps more) orbiting very close to Alpha-Centauri B in a stable orbit"? 
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Help needed!

Many people at one point of their life want to be a astronaut, well, here's your chance to help! You can't be an astronaut, but you can help astronomers by analyzing some images to find super massive black holes in the center of galaxies.

All you have to do is match images taken both in infrared and radio wavelengths – and this will give information on whether or not the galaxy has a supermassive black hole at its center. The infrared data comes from NASA’s Wide-Field Infrared Survey Explorer (WISE) satellite, while the radio data is from the Karl G. Jansky Very Large Array (VLA) in New Mexico – astronomers plan to include even more data.

“It takes about a minute to learn what to do,” said Julie Banfield, an Australian coordinator of the international project from the Commonwealth Scientific and Industrial Research Organization (CSIRO). “Then to actually work with the images takes only a few seconds each—perhaps a couple of minutes for the really tough ones. You just need to match up a couple of pictures and look for what you think is the galaxy at their center.”

Where can you sign up you ask?

It's here: http://bit.ly/19fVD6l

Happy hunting!
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Wormholes and quantum entanglement are linked together?
Can this be the a step towards unifying quantum mechanics and relativity?

One of the predictions derived from Einsten’s theory of general relativity is the existence of wormholes – spacetime shortcuts. In theory such bridges may offer instantaneous travel between the two bridgeheads or wormholes even if these are light-years away from each other. Two independent studies suggest that there’s a link between quantum entanglement and wormholes, or to be more precise: each wormhole has a corresponding pair just like two entangled quantum particles.
Quantum entanglement is nothing short of bizarre. In a pair of entangled particles,  a change in the quantum characteristics of one of the particles can’t happen without also causing a change in the other particle, even if these particles are millions of miles away. This concomitant change happens instantaneously, which is  why some people liken it to teleportation. I know, it’s a really strange and  non-intuitive aspect of the quantum theory of matter – this is why Einstein called it “spooky action at a distance.” For what’s it worth, although quantum entanglement was first theorized a long time ago, only recently did researchers prove that it’s real.

ENTANGLED WORMHOLES

Theoretical physicists Juan Martín Maldacena at the Institute for Advanced Study in Princeton and Leonard Susskind at Stanford University argue that wormholes are nothing but pairs of black holes entangled together. A proposed mechanism of wormhole generation would be that when a black is born, its pair is simultaneously created as well. Moreover, they conjectured that entangled particles such as electrons and photons were connected by extraordinarily tiny wormholes.

Read here: http://bit.ly/IMKpzd 
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Michael McMorris's profile photoSergio Lample Marcos's profile photoSPACE & EARTH's profile photoRAJEEV RANJAN's profile photo
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the pic is mind bogglin/bobblin
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Dark matter found with X-ray?

Two teams working on the search for dark matter have independently suggested the search could concentrate at a specific X-ray wavelength, following study of data collected by the XMM-Newton space observatory.

While it's not a proof of anything just yet, the two groups – one from the Harvard-Smithsonian Centre for Astrophysics, the other from the Netherlands' Leiden Observatory – have spotted a spectrographic line in X-rays at 3.5 kiloelectron volts, and this line is observed across 73 galaxy clusters.

Readers familiar with particle physics discoveries such as the search for the Higgs boson will be aware that identifying possible energies is a big thing to particle hunters. It's an interface between the theoretician and the experimentalist: “If particle W exists, its decay should emit Particles X and Y, carrying energy Z”.

What's intriguing the scientists is this: that particular energy doesn't match anything we already know about what generates galactic X-rays. Science quotes one of the scientists, Maxim Markevitch of the NASA Goddard Space Flight Center, as putting it this way: “We could not match it with anything that would come from a thermal plasma”.

You can read more here: http://bit.ly/Nqdt2f
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Both, dark matter and dark energy are comprised of "All" known and unknown "Atomic" elements (in gigantic clusters) floating, randomly around looking for trouble and are the microscopic building blocks of our universe.
Think of them as our, "Universal" ocean (which is constantly moving) and think of the GAS and STARS, ETC, as the occupants that were created by these building blocks in that watery universe. Works for me,, (noreply wanted)  
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Really amazing Supernovae
 
We present you 29 gorgeous images of supernovae. Which is your favorite? http://oak.ctx.ly/r/m9tp
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Super-Earth

The alien worlds known as "super-Earths" may be more like our own planet than previously thought, a new study suggests.
It suggests that these planets can have oceans and continents just like we have on Earth!

#superearth   #space  
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Space weather

What is space weather?
Many of us watch the weather forecasts on Earth and make certain decisions about things to take with them, time to go out for a drive, etc. Like weather on Earth, we also have space weather, the space weather originates because of the Sun. Solar phenomena (like coronal mass ejection[CME], solar flares, coronal holes, and solar prominence's) which releases matter from Sun into space is the starting point of the processes that develop the space weather.

Coronal mass ejection(CME)
Coronal mass ejections consist of matter thrown out from the corona, the sun’s outer atmosphere. The corona’s reach, its density, and most other characteristics are structured by strong magnetic fields that are generated by conditions beneath the sun’s visible surface. When the magnetic fields loop back on themselves, great masses of the electrically-charged solar atmosphere become confined within their lines of force. At some point the highly charged gas or plasma—which may amount to as much as a billion tons of matter—can suddenly and violently explode, blowing out huge plumes of solar atmosphere at speeds of several million miles an hour.
More here: http://1.usa.gov/1esBm0E

Solar flares
Solar flares are intense releases of energy that originate in the sun’s chromosphere, a thin layer of mostly hydrogen that lies between the sun’s visible surface and the corona. Solar flares can last for minutes or hours, and are the largest explosive events in the solar system. The energy released in a single flare can be the equivalent of 40 billion Hiroshima-size atomic bombs.

Coronal holes
Coronal holes, viewed in the x-ray waveband, show as exactly what their name states: holes in the corona. The holes can last for months to years, and are rooted in large cells of unipolar magnetic fields that emanate from the sun’s surface. The field lines of the cells extend far away from the sun, allowing a continuous outflow of high-velocity solar material to travel along them into open space.

Solar prominence
Solar prominences originate as clouds of solar material held above the sun’s surface by fields of magnetic force. The clouds remain suspended, relatively quiescent—until they erupt, releasing large amounts of solar matter into space.

How are we protected from all this?
Magnetosphere to the rescue!
A magnetosphere is the region surrounding a planet where the planet's magnetic field dominates. Because the ions in the solar plasma are charged, they interact with these magnetic fields, and solar wind particles are swept around planetary magnetospheres.The shape of the Earth's magnetosphere is the direct result of being blasted by solar wind. Solar wind compresses its sunward side to a distance of only 6 to 10 times the radius of the Earth.
More here: http://1.usa.gov/1lCqpvH and here http://1.usa.gov/1a3HxZI 

Why is space weather so important?
Why are people interested in space weather? Why should you care about space weather? The Sun is the main source of energy for our planet. It makes plants grow and makes our weather go. Changes in the Sun could make a big change in our weather and climate on Earth. Radiation from space weather storms can damage satellites, like the ones used for cell phone communications. That radiation can also harm astronauts, or even people on some kinds of jet airplane flights. Really powerful space weather storms can even knock out the electricity over large areas.

Has all this phenomena caused any harm to us? Not yet, but.....
On a cool September night in 1859, campers out in Colorado were roused from sleep by a “light so bright that one could easily read common print,” as one newspaper described it. Some of them, confused, got up and began making breakfast.
Farther east, thousands of New Yorkers ran out onto their sidewalks to watch the sky glow, ribboned in yellow, white and crimson. Few people had ever seen an aurora that far south — and this one lit up the whole city.
At the time, it was a dazzling display of nature. Yet if the same thing happened today, it would be an utter catastrophe.
More here: http://wapo.st/1aqF1ZQ

Also see:  http://bit.ly/19LAFfM

Want to know current space weather? Head here: http://bit.ly/spcweat
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Arad Vejdani's profile photoValdis Kletnieks's profile photoPhil Hayden's profile photoRaad Salih's profile photo
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+Valdis Kletnieks
 THANKS FOR THAT INFO LUV...XXX
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Albedo: Fraction of Sun’s radiation reflected from a surface.

Earlier the measurements of distance of the planets were done by measuring the amount of light they reflected. SInce all the planets in the solar system in reflect light form the Sun, albedo is defined as fraction of Sun’s radiation reflected from a surface. The term has its origins from the Latin word albus, meaning “white”. It is quantified as the proportion, or percentage of solar radiation of all wavelengths reflected by a body or surface to the amount incident upon it. An ideal white body has an albedo of 100% and an ideal black body, 0%.

But this technique is also used to determine distance to other stars, in the late 1600s Isaac Newton measured the distance to the star Sirius using the albedo and the inverse square law for light. Newton calculated the distance to Sirius as 12.6 light years where as the actual distance is about 8.6 light years. It's good, considering that he did not have the technology we have now. Distance measurement using this technique is done even now, but along with other techniques.

Here's more: http://bit.ly/1l9BjZB and more http://bit.ly/1gRXZAl and more http://bit.ly/1cNc5Mj
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Astrophysics! You will know everything about the cosmos right here!! Read introduction for more info.
Introduction
Do you want to know why planets move in elliptical orbits and not in a square or rectangle path?? Or how Sun gives us heat?? What a black hole is?? Why Einstein is famous and what he did?? Or what is LHC? Or maybe you just want to know why do we stick to earth and don't fly off!! If you want to know this then you are in luck! We will provide you with answers, you just have to ask.

If you have any questions about the Universe, you can ask them here by tagging* +Astrophysics *in the question. I'll share it so that anyone who knows the answer to it can help you solve your doubts. :)

For example:

Who proposed that Sun is in middle of the Solar System? +Astrophysics

Majority of the stuff I post here is not written by me.