memnock writes: The Digital Scholarship Lab at the University of Richmond digitized the atlas: 'Here you will find one of the greatest historical atlases: Charles O. Paullin and John K. Wright's Atlas of the Historical Geography of the United States, first published in 1932. This digital edition reproduces all of the atlas's nearly 700 maps.'
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KentuckyFC writes: In November 2012, a group of Japanese scientists discovered that the concentration of carbon-14 in Japanese cedar trees suddenly rose between 774 AD and 775 AD. Others have since found similar evidence and narrowed the date to 773 AD. Astronomers think this stuff must have come from space so now the quest is on to find the extraterrestrial culprit. Carbon-14 is continually generated in the atmosphere by cosmic rays hitting nitrogen atoms. But because carbon-14 is radioactive, it naturally decays back into nitrogen with a half-life of about 5700 years. This constant process of production and decay leaves the amount of carbon-14 in the atmosphere relatively constant at about one part in a trillion will be carbon-14. One possible reason for the increase is that the Sun belched a superflare our way, engulfing the planet in huge cloud of high energy protons. Recent calculations suggest this could happen once every 3000 years and so seems unlikely. Another possibility is a nearby supernova, which bathed the entire Solar System in additional cosmic rays. However, astronomers cannot see any likely candidates nearby and there are no historical observations of a supernova from that time. Yet another possibility is that a comet may have hit the Earth, dumping the extra carbon-14 in the atmosphere. But astronomers have ruled that out on the basis that a comet carrying enough carbon-14 must have been over 100 km in diameter and would surely have left other evidence such as an impact crater. So for the moment, astronomers are stumped.
An anonymous reader writes: OpenSSH 6.5 has been released. It features numerous new features, a lot of bugfixes and sandboxing support for FreeBSD.
Hugh Pickens DOT Com writes: Reuters reports that pressure on President Obama to approve the Keystone XL pipeline increased on Friday after a State Department report played down the impact it would have on climate change, irking environmentalists and delighting proponents of the project. The long-awaited environmental impact statement concludes that the Keystone XL pipeline would not substantially worsen carbon pollution, leaving an opening for Obama to approve the politically divisive project as it appears to indicate that the project could pass the criteria Obama set forth in a speech last summer when he said he would approve the 1,700-mile pipeline if it would not “significantly exacerbate” the problem of greenhouse gas emissions. The oil industry applauded the review. “After five years and five environmental reviews, time and time again the Department of State analysis has shown that the pipeline is safe for the environment,” says Cindy Schild, the senior manager of refining and oil sands programs at the American Petroleum Institute, which lobbies for the oil industry. Environmentalists say they are dismayed at some of the report’s conclusions and disputed its objectivity, and add that the report also offers Obama reasons to reject the pipeline. The report concludes that the process used for producing the oil — by extracting what are called tar sands or oil sands from the Alberta forest — creates about 17 percent more greenhouse gas emissions than traditional oil (PDF). But the report concludes that this heavily polluting oil will still be brought to market. Energy companies are already moving the oil out of Canada by rail. “At the end of the day, there’s a consensus among most energy experts that the oil will get shipped to market no matter what,” says Robert McNally. “It’s less important than I think it was perceived to be a year ago, both politically and on oil markets.”