The link between mathematics and music has always been there - our ears hear in frequencies and even before those frequencies were known in physics terms, ancient philosopher-scientists had determined that the language of math linked areas as remote as planetary motion and harmony. "There is music in the spacing of the spheres," wrote Pythagoras. The Pythagoreans didn't have irrational numbers, negative numbers or even a zero but they didn't need those for their kind of symbolism.

Researchers from Germany and Switzerland did an analysis on sediment cores from the Black Sea and concluded that, for a brief period during the last ice age, a compass at the Black Sea would have pointed south instead of north. And that wasn't the worst thing going on around the same time.

41,000 years ago, say the researchers, a complete and rapid reversal of the geomagnetic field occurred. Along with the Black Sea sediment cores, they look at other studies in the North Atlantic, the South Pacific and Hawaii, and say it proves that this polarity reversal was a global event. 

Supernova 1987A in the Large Magellanic Cloud was close enough to be seen by the naked eye when its light first reached Earth in February of 1987.  During the explosion's peak, fingerprints of elements from oxygen to calcium were detected, representing the outer layers of the ejecta and soon after, signatures of the material synthesized in the inner layers could be seen in the radioactive decay of nickel-56 to cobalt-56, and its subsequent decay to iron-56. 

After more than 1000 hours of observation by Integral, high-energy X-rays from radioactive titanium-44 in supernova remnant 1987A have been detected for the first time. The radioactive decay has likely been powering the glowing remnant around the exploded star for the last 20 years.

The economic downtown that began in 2008 has been hardest on the mental health of men in England - yet it isn't the actual unemployment and falling household income the authors blame. They blame the threat of losing their jobs in a society that places an unrealistic level of pressure on males to be the breadwinners.

They base their findings on data taken from the national representative annual Health Survey for England for adults aged 25 to 64, between 1991 and 2010.  Response rates during the period varied from 85 per cent in 1991 to 64 per cent in 2008, and included almost 107,000 people.

Researchers from Lawrence Berkeley National Laboratory may have discovered why so little that makes sense results from political meetings - moderately high indoor concentrations of carbon dioxide (CO₂) can significantly impair people's decision-making performance. 

In 1428 AD, while King Alfonso V was ordering Sicilian Jews into conversion sermons and the Ottomans were consolidating in Europe, the city-states of Tenochtitlan, Texcoco, and Tlacopan formed the Triple Alliance, which became the Aztec empire and ruled the Valley of Mexico until the Spaniards arrived a century later. 

The term 'Aztec' has become a little confusing since then. There were no 'Aztec' people, the people of Mexico primarily made up what were later called Aztecs, and the Aztecs were made up of many cultures, they were just dominated by conquering city-states. Historians call such a structure a hegemonic empire as compared to the traditional meaning like with Rome or Mongolia.