Category Astronomy/Space

Galaxy Clusters offer Clues to Dark Matter and Dark Energy

A massive, young galaxy cluster seen in X-rays (blue), visible light (green), and infrared light (red). Image by X-ray: NASA/CXC/Univ of Missouri/M.Brodwin et al.; optical: NASA/STScI; infrared: JPL/CalTech

A massive, young galaxy cluster seen in X-rays (blue), visible light (green), and infrared light (red). Image by X-ray: NASA/CXC/Univ of Missouri/M.Brodwin et al.; optical: NASA/STScI; infrared: JPL/CalTech

It’s a cosmic irony: the biggest things in the universe can also be the hardest to find. Elizabeth Blanton, a Boston University associate professor of astronomy, started hunting for distant galaxy clusters more than 20 years ago. A single galaxy cluster can be as massive as a quadrillion suns, yet faraway clusters are so faint that they are practically invisible to all but the biggest Earth-bound telescopes. Distant clusters hold pieces of the story of how the web-like structure of the universe first emerged and could help illuminate the true nature of dark energy and dark matter.

Now, ...

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Black Hole Models Contradicted by Hands-on Tests

Sandia National Laboratories' Guillaume Loisel poses with Sandia's Z machine, where hands-on experiments contradicted a long-standing assumption about the X-ray spectra from the vicinity of black holes in space. Loisel is the lead author of a paper on the experimental results, published in Physical Review Letters. Credit: Randy Montoya, Sandia National Laboratories

Sandia National Laboratories’ Guillaume Loisel poses with Sandia’s Z machine, where hands-on experiments contradicted a long-standing assumption about the X-ray spectra from the vicinity of black holes in space. Loisel is the lead author of a paper on the experimental results, published in Physical Review Letters. Credit: Randy Montoya, Sandia National Laboratories

Small cracks in basic theories. A long-standing but unproven assumption about the X-ray spectra of black holes in space has been contradicted by hands-on experiments performed at Sandia National Laboratories’ Z machine. Z, the most energetic laboratory X-ray source on Earth, can duplicate the X-rays surrounding black holes that otherwise can be watched only from a great distance and then theorized about...

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Galaxy 5 Billion light-years away shows we live in a Magnetic Universe

Astronomers observed the magnetic field of a galaxy five billion light-years away. The galaxy provides important insight into how magnetism in the universe formed and evolved. Credit: Bill Saxton, NRAO/AUI/NSF; NASA, Hubble Heritage Team, (STScI/AURA), ESA, S. Beckwith (STScI). Additional Processing: Robert Gendler

Astronomers observed the magnetic field of a galaxy five billion light-years away. The galaxy provides important insight into how magnetism in the universe formed and evolved. Credit: Bill Saxton, NRAO/AUI/NSF; NASA, Hubble Heritage Team, (STScI/AURA), ESA, S. Beckwith (STScI). Additional Processing: Robert Gendler

A chance combination of a gravitational lens and polarized waves coming from a distant quasar gave astronomers the tool needed to make a measurement important to understanding the origin of magnetic fields in galaxies. The scientists used the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) to study a star-forming galaxy that lies directly between a more-distant quasar and Earth...

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40 years on, Voyager still Hurtles through space

Artist's concept of NASA's Voyager spacecraft. Credit: NASA/JPL-Caltech

Artist’s concept of NASA’s Voyager spacecraft. Credit: NASA/JPL-Caltech

Are we alone? Forty years ago, NASA rocket scientists sought to answer this question by launching the Voyager spacecraft, twin unmanned spaceships that would travel further than any human-made object in history. When Voyager 1 and 2 launched about two weeks apart in 1977 from Cape Canaveral, Florida, scientists knew little about the outer planets in our solar system, and could hardly imagine the scope of their upcoming space odyssey.

“None of us knew, when we launched 40 years ago, that anything would still be working, and continuing on this pioneering journey,” said Voyager project scientist Ed Stone...

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