New data obtained by NASA's GRAIL mission reveals that the Procellarum region on the near side of the moon - a giant basin often referred to as the "man in the moon" - likely arose not from a massive asteroid strike, but from a large plume of magma deep within the moon's interior.
The Procellarum region is a roughly circular, volcanic terrain some 1,800 miles in diameter - nearly as wide as the United States. One hypothesis suggested that it was formed by a massive impact, in which case it would have been the largest impact basin on the moon. Subsequent asteroid collisions overprinted the region with smaller - although still large - basins.
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Americans love their dogs, but they don't always love to pick up after them. And that's a problem. Dog feces left on the ground wash into waterways, sometimes carrying bacteria — including antibiotic-resistant strains — that can make people sick. Now scientists have developed a new genetic test to figure out how much dogs are contributing to this health concern, according to a report in the ACS journal Environmental Science & Technology.
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Advocates of nuclear energy have long been predicting its renaissance, yet this mode of producing electricity has been stalled for years. Renewable energy, by contrast, continues to expand rapidly, even if it still has a long way to go to catch up with fossil fuel power plants, writes Worldwatch Institute Senior Researcher Michael Renner in the Institute’s latest Vital Signs Online analysis (bit.ly/NuclearRE).
Nuclear energy’s share of global power production has declined steadily from a peak of 17.6 percent in 1996 to 10.8 percent in 2013. Renewables increased their share from 18.7 percent in 2000 to 22.7 percent in 2012.
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Wildlife in Yellowstone National Park is undergoing dramatic shifts with consequences that are beginning to return the landscape to conditions not seen in nearly a century, according to a series of new studies.
In the park's northeast section, elk have decreased in number in their historic winter range in the Lamar Valley and are now more numerous outside the park. This change in elk numbers and distribution can be traced back to the reintroduction of wolves in 1995-96. Scientists have hypothesized that wolves affect both the numbers and the behavior of elk, thereby reducing the impact of browsing on vegetation, a concept known as a "trophic cascade."
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Tropical forest restoration projects are exciting research sites for scientists studying factors that affect ecosystem recovery. Here, scientists are trying to understand plant community succession, i.e. the process of recovery after cleared lands are abandoned and allowed to regrow naturally. One of the most important components of this recovery process is seed dispersal, since seeds from nearby forests allow a deforested habitat to become populated again by native plants and trees.
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