Slashdot reader schwit1 shares a report from CNN: A team of 12 geologists and archaeologists from across the United Kingdom unveiled research this month that traces some of the prehistoric monument's smaller stones to two quarries in western Wales. The team also found evidence of prehistoric tools, stone wedges and digging activity in those quarries, tracing them to around 3000 BC, the era when Stonehenge's first stage was constructed. It's rock-solid evidence that humans were involved in moving these "bluestones" to where they sit today, a full 150 miles away, the researchers say. "It finally puts to rest long-standing arguments over whether the bluestones were moved by human agency or by glacial action," University of Southampton Archeology Professor Joshua Pollard said in an email. Slashdot reader schwit1 adds: "This leaves the question of how..."

Renewable energy use and reduced energy use overall have helped carbon emissions remain flat or below average as the global economy continued to grow over the years. But, as new research has found, government policy also appears to play a large role. Slashdot reader AmiMoJo shares a report from Ars Technica: The researchers started by identifying countries that show a "peak and decline" pattern of carbon emissions since the 1990s. They came up with 18, all but one of them in Europe -- the exception is the United States. For comparison, they created two different control groups of 30 countries, neither of which has seen emissions decline. One group saw high GDP growth, while the second saw moderate economic growth; in the past, these would have been associated with corresponding changes in emissions. Within each country, the researchers looked into whether there were government energy policies that could influence the trajectory of emissions. They also examined four items that could drive changes in emissions: total energy use, share of energy provided by fossil fuels, the carbon intensity of the overall energy mix, and efficiency (as measured by energy losses during use). On average, emissions in the decline group dropped by 2.4 percent over the decade between 2005 and 2015.

Half of this drop came from lowering the percentage of fossil fuels used, with renewables making a large contribution; another 35 percent came from a drop in energy use. But the most significant factor varied from country to country. Austria, Finland, and Sweden saw a drop in the share of fossil fuels within their energy mix. In contrast, a drop in total energy use was the biggest factor for France, Ireland, the Netherlands, Spain, and the United Kingdom. The U.S. was an odd one out, with all four possible factors playing significant roles in causing emissions to drop. For the two control groups, however, there was a single dominant factor: total energy use counted for 75 and 80 percent of the change in the low- and high-economic growth groups, respectively. But there was considerably more variability in the low-economic growth group. All of the high-growth group saw increased energy use contribute 60 percent of the growth in emissions or more. In contrast, some of the low-growth group actually saw their energy use drop. So why are some countries so successful at dropping their emissions? Part of it is likely to be economic growth, but the biggest reason may have to do with government policies. "By 2015, the countries in the group that saw declining emissions had an average of 35 policies that promoted renewable energy and another 23 that promoted energy efficiency," reports Ars Technica. "Both of those numbers are significantly higher than the averages for the control groups. And there's evidence that these policies are effective. The number of pro-efficiency policies correlated with the drop in energy use, while the number of renewable policies correlated with the drop in the share of fossil fuels."

A pair of Hewlett Packard Enterprise servers sent up to the International Space Station in August 2017 as an experiment have still not come back to Earth, three months after their intended return. From a report: Together they make up the Spaceborne Computer, a Linux system that has supercomputer processing power. They were sent up to see how durable they would be in space with minimal specialist treatment. After 530 days, they are still working. Their return flight was postponed after a Russian rocket failed in October 2018. HPE senior content architect Adrian Kasbergen said they may return in June 2019 if there is space on a flight but "right now they haven't got a ticket." The company is working with Nasa to be "computer-ready" for the first manned Mars flight, estimated to take place in about 2030. The company is also working with Elon Musk's SpaceX.

Prominent astronomer Dr Scott Sheppard, of the Carnegie Institution for Science in Washington D.C., has discovered a new object in the distant reaches of our solar system and given it the name FarFarOut. "At 140 times further away from the sun than our own planet is, the newly identified body -- if its discovery is confirmed -- will become the furthest known object in our solar system," reports The Guardian. Sheppard's discovery was made after his team was analyzing astronomical data to track down Planet Nine, a yet-to-be-discovered body thought to have 10 times the mass of Earth. From the report: Sheppard said he made the discovery of FarFarOut when a lecture he was due to give on his team's work was postponed and he went back to analyzing his data. He said FarFarOut was somewhat mysterious. "It is very faint; it is on the edge of our ability to detect it," Sheppard said. "We don't know anything about the orbit of this object, we just know it is far, far out." Sheppard said further observations were in the offing to shed more light on the find. The current record holder -- a dwarf planet at 120 times the Earth-sun distance -- was named merely FarOut when it was spotted by the same team in December last year.