Wednesday, March 27, 2013

Super-dense alien planet could be entirely new type

Mysterious dense "super-earths" discovered by Kepler could be the "fossil cores" of wandering ice giants.

Among the most mysterious finds of NASA’s Kepler space mission to find exoplanets are bodies too heavy for their size. In some cases, planets the size of Earth are denser than pure iron, according to a report in the journal Nature.
No standard theories about planet formation could explain such dense bodies. “There is no way to explain that in the Solar System,” says Olivier Grasset, a geophysicist at the University of Nantes in France.
But scientists believe these planets could be the "fossil cores" of ice giants similar to Neptune that veered too close to their suns, according to research presented this week at a meeting on exoplanets at the Royal Society in London. These cores would have formed under the intense pressure of their outer layers -- 5 million times the atmospheric pressure on Earth - and temperatures up to 6,000 kelvin.

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Wednesday, March 13, 2013

crystal found at bottom of English Channel may be a fabled sunstone

Historians have long wondered at the ability of Vikings explorers to travel long stretches of open water. Some say they used transparent calcite crystals — whose properties can allow a skilled sailor to guess the position of the sun during overcast or foggy days — as navigational aids.

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Monday, March 11, 2013

Stonehenge Was Ancient Rave Spot

British researchers unveiled a new theory for the origins of Stonehenge, saying the ancient stone circle was originally a graveyard and venue for mass celebrations.
The findings would overturn the long-held belief that Stonehenge on Salisbury Plain in southwestern England was created as a Stone Age astronomical calendar or observatory.
A team led by Professor Mike Parker Pearson of University College London said Stonehenge, a UNESCO World Heritage site, is both older and had a different function than previously thought.
"In many ways our findings are rewriting the established story of Stonehenge," Parker Pearson said.
The archaeologists carried out a decade of research which included excavations, laboratory work and the analysis of 63 sets of ancient human remains.
They said the original Stonehenge appeared to have been a graveyard for elite families built around 3000 BC, 500 years earlier than the site that is famous today.
The remains of many cremated bodies were marked by the bluestones of Stonehenge, Pearson said.
Further analysis of cattle teeth from 80,000 animal bones excavated from the site also suggest that around 2500 BC, Stonehenge was the site of vast communal feasts.
These would have been attended by up to one tenth of the British population at one time in what Parker Pearson said resembled "Glastonbury festival and a motorway building scheme at the same time."
It seemed that ancient people traveled to celebrate the winter and summer solstices but also to build the monument, he said.