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Amy Shira Teitel is a freelance space writer whose work appears regularly on Discovery News Space and Motherboard among many others. She blogs, mainly about the history of spaceflight, at Vintage Space, and tweets at @astVintageSpace.
The idea of a red sky at night used to invoke beautiful images of vibrant sunsets, the product of warm sunlight bathing the sky near the horizon. The adage of “red sky at night, sailor’s delight” refers to a calm night ahead; a red sunset suggests a high-pressure system in the west is bringing calm weather. But red skies at night have taken on a new meaning in recent decades. As outdoor lighting become increasingly prominent, our night skies are gradually turning from black to red.
War Has Deep Roots in Human Nature, But It’s Not Inevitable
Is Autism an “Epidemic” or Are We Just Noticing More People Who Have It »
We (Apparently) Found the Higgs Boson. Now, Where the Heck Did It Come From
Amir D. Aczel has been closely associated with CERN and particle physics for a number of years and often consults on statistical issues relating to physics. He is also the author of 18 popular books on mathematics and science, and has been awarded both Guggenheim Foundation and Sloan Foundation fellowships. Many thanks to Steven Weinberg of the University of Texas at Austin and to Barton Zwiebach of MIT for their helpful comments.
'm just toying around with this idea at the moment. If I start using photo exposure PCB type production, I'm probably going to need a light box. I have tried using spray on photo-sensitive resist and exposure to the sun. It was a complete failure. Presensitised boards, and a light box seem the way to go. I haven't read much about this technique on the web, so I'm still a bit cautious.
Most commercial light boxes are very expensive. I think I should be able to put one together using a brief case, some UV CCFL tubes (or better still UV fluorescent), a μC, an LED display, a relay or two, a few switches, and a couple of pieces of glass.
Magnetic field sensors based on organic thin-film materials have attracted considerable interest in recent years as they can be manufactured at very low cost and on flexible substrates. However, the technological relevance of such magnetoresistive sensors is limited owing to their narrow magnetic field ranges (~30 mT) and the continuous calibration required to compensate temperature fluctuations and material degradation. Conversely, magnetic resonance (MR)-based sensors, which utilize fundamental physical relationships for extremely precise measurements of fields, are usually large and expensive. Here we demonstrate an organic magnetic resonance-based magnetometer, employing spin-dependent electronic transitions in an organic diode, which combines the low-cost thin-film fabrication and integration properties of organic electronics with the precision of a MR-based sensor. We show that the device never requires calibration, operates over large temperature and magnetic field ranges, is robust against materials degradation and allows for absolute sensitivities of <50 nT Hz−1/2.
Asteroid mining brings up some tricky legal questions.
By Frans von der Dunk, as told to Veronique Greenwood.
Frans von der Dunk is the Harvey and Susan Perlman Alumni and Othmer Professor of Space Law at the University of Nebraska College of Law. In addition, he is the director of a space law and policy consultancy, Black Holes, based in the Netherlands.
The manmade changes pushing the planet toward a critical transition
Nature changes gradually—until it doesn’t. As the changes in an ecosystem pile up, they can push the system past a “critical threshold,” and then the change can become extremely fast (in relation to geological timescales) and unstoppable. And in a review in the journal Nature, researchers suggest that the same thing is happening to the whole world: Humans could be driving Earth’s biosphere towards a tipping point beyond which the planet’s ecosystems will collapse abruptly and irreversibly.
Four and a half billion years ago, the place we now call the solar system was a vast cloud of gas and dust enshrouding a newborn star. Gradually those dust grains cohered and formed pebbles, which then collided and coalesced into boulders. Over the course of about 100 million years, most of the material in that nebulous cloud accreted into the existing eight planets—four rocky (including Earth) and four gaseous. Or at least that’s how astronomers thought the story went.
On June 5/6, 2012, the planet Venus crossed the face of the Sun. This event, called a transit, was seen across the Earth by people who viewed it in person as well as online live. I asked for pictures, and received dozens of them from readers all over the world - and above it! I chose the images in this gallery because they made me smile, they made me laugh, and they made me proud of how wonderful the Universe is, and how we humans appreciate it.
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Nature Genetics in association with the Wellcome Trust is pleased to announce the sixth Genomics of Common Diseases meeting.
The Genomics of Common Diseases 2012
September 19-22, 2012, Bolger Center, Potomac, MD, USA
This sixth annual conference marks the 20th anniversary year of the founding of Nature Genetics.Over the past six years, our understanding of the genetic architecture of disease has been progressively redefined by genome-wide association studies characterizing common variation, the fine mapping of these associated regions, the emergence and growth of new sequencing technologies, and the assessment of rare variant association.
Is Einstein's Greatest Work All Wrong—Because He Didn't Go Far Enough?
From a farmhouse in the English countryside, gentleman scientist Julian Barbour plots to take relativity to its logical extreme and redefine the very nature of gravity, space, and time.
Physicist Julian Barbour and his theory of time were previously featured in a cover story from December 2000.
Galaxy cluster Abell 1689 seems to be held together by swaths of unseen dark matter;
blue shows its theoretically inferred location. But could dark matter be an illusion?
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The idea of a red sky at night used to invoke beautiful images of vibrant sunsets, the product of warm sunlight bathing the sky near the horizon. The adage of “red sky at night, sailor’s delight” refers to a calm night ahead; a red sunset suggests a high-pressure system in the west is bringing calm weather. But red skies at night have taken on a new meaning in recent decades. As outdoor lighting become increasingly prominent, our night skies are gradually turning from black to red.
نویسنده: 
Illustrations by Elisabeth Roen Kelly
Galaxy cluster Abell 1689 seems to be held together by swaths of unseen dark matter; 
