Two-dimensional material shows promise for optoelectronics: LEDs, photovoltaic cells, and light detectors

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Team creates LEDs, photovoltaic cells, and light detectors using novel one-molecule-thick material. Researchers have used a novel material that's just a few atoms thick to create devices that can harness or emit light. This proof-of-concept could lead to ultrathin, lightweight, and flexible photovoltaic cells, light emitting diodes (LEDs), and other optoelectronic devices, they say.

via Science Daily

Gamma Rays from Galactic Center Dark Matter?

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What is creating the gamma rays at the center of our Galaxy? Excitement is building that one answer is elusive dark matter. Over the past few years the orbiting Fermi Gamma-ray Space Telescope has been imaging our Galaxy's center in gamma-rays. Repeated detailed analyses indicate that the region surrounding the Galactic center seems too bright to be accounted by known gamma-ray sources. A raw image of the Galactic Center region in gamma-rays is shown above on the left, while the image on the right has all known sources subtracted -- leaving an unexpected excess. An exciting hypothetical model that seems to fit the excess involves a type of dark matter known as WIMPs, which may be colliding with themselves to create the detected gamma-rays. This hypothesis is controversial, however, and debate and more detailed investigations are ongoing. Finding the nature of dark matter is one of the great quests of modern science, as previously this unusual type of cosmologically pervasive matter has shown itself only through gravitation. Astrophysicists: Browse 750+ codes in the Astrophysics Source Code Library
Tomorrow's picture: dusty rose

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Zazzle Space Gifts for young and old

I spy… Rosetta’s comet

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Space science image of the week: Rosetta’s target comet, back in the field of view of ground-based telescopes, has brightened over the last four months

via ESA Space Science

http://www.esa.int/spaceinimages/Images/2014/02/Comet_Churyumov_Gerasimenko_on_28_February_2014

Atomically thin, flexible, semi-transparent solar cells created

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A lot of research has been done on graphene recently -- carbon flakes, consisting of only one layer of atoms. As it turns out, there are other materials too which exhibit remarkable properties if they are arranged in a single layer. One of them is tungsten diselenide, which could be used for photovoltaics. Ultrathin layers made of Tungsten and Selenium have now been created; experiments show that they may be used as flexible, semi-transparent solar cells.

via Science Daily