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Fire-fountain carbon sheds light on lunar origins

The moon was once thought to be virtually devoid of water and other volatile materials — a presumed consequence of extreme heating during its formation. But a recent study of lunar volcanic glasses, from samples brought back by the Apollo 15 and 17 missions, is adding to the growing stack of recent evidence suggesting the moon is not the volatile-free place scientists once suspected. The findings bring us one step closer to understanding the moon’s origins.

03 Feb 2016

What are the odds?: Automated system calculates the likelihood that asteroids will hit Earth

By some estimates, Earth is pelted each year by tens of thousands of asteroids — from souvenir-sized nuggets 10 grams and up to the occasional meters-wide boulder. Spotting larger Earth-bound impactors that could cause serious destruction, while they’re still in space, has been a priority of the planetary science community for years. But many space objects are small enough that they can only be detected days or hours before impact — if at all. In a new study, scientists have tested and automated a new technique called systematic ranging that’s intended to rapidly calculate the probability — from only a handful of observations — that newly discovered asteroids will hit Earth.

26 Jan 2016

Modeling 'magma mush' could reveal volcanic histories

Volcanic eruptions can spew large amounts of molten rock and ash, putting nearby communities as well as aircraft at risk. Gas emissions and earthquakes sometimes offer clues of when an eruption will occur, but the internal workings of volcanoes are largely unobservable. In a recent study, researchers illuminated these internal processes with a computer simulation that models the flow of the part-liquid, part-solid “magma mush” beneath volcanoes.

18 Dec 2015

Peculiar shape of hair ice linked to fungus

If you have ever taken a morning hike through the woods and seen strange, silky-looking ice on fallen logs, you might have been observing a phenomenon that has puzzled hikers and scientists alike for at least a century. In a new study, researchers examining so-called hair ice have unraveled an explanation for these peculiar formations.

13 Oct 2015

Subducted seawater the source of fluid-rich diamonds

Subducting oceanic plates that dive hundreds of kilometers beneath Earth’s surface carry with them cargoes of sediment and seawater. As the plate heats up the deeper it sinks, this seawater not only initiates melting in the rock above it, but can also trigger diamond formation, suggest the authors of a new study in Nature.

30 Sep 2015

Arctic climate change marked by warmer, wetter conditions

At least since satellite observations began four decades ago, climbing temperatures have chipped away at Arctic sea ice causing earlier spring melting and later autumn freezing. Because ice reflects more sunlight than water does, shrinking sea-ice cover means that Arctic waters soak up more solar energy, which affects climate both regionally and globally. Now, a new study has documented how Arctic warming leads to wetter air and increased cloud cover, particularly during autumn and winter, which spurs even more warming in a self-reinforcing cycle.

28 Aug 2015

Volcanic lightning turns ash into glass

Within the ash plumes of explosive volcanic eruptions, collisions among countless pyroclastic particles sometimes lead to the buildup of static charges that discharge dramatically as volcanic lightning. In a new study, researchers have found that this lightning can, in turn, melt and fuse ash particles into distinctive glassy grains called spherules.

07 Aug 2015

Beached iceberg alters Antarctic marine communities

Studying the effects of expanding sea ice around Antarctica has been challenging, however, as it is difficult to predict exactly where sea ice will expand and whether it will stick around long enough to make a difference on marine life. But a rare event involving an iceberg bigger than the island of Manhattan created just the environment that Graeme Clark, an ecologist at the University of New South Wales in Australia, and his colleagues needed to study how the sudden advent of long-term sea-ice cover affects marine communities.

21 Jul 2015

Brachiopod die-off signaled mid-Permian mass extinction

Since the explosion of complex lifeforms before the turn of the Cambrian, the expansion of life on Earth has been punctuated by a quintet of global mass extinctions known as the “Big Five.” The biggest of these happened toward the end of the Permian Period about 252 million years ago, when 95 percent of all species went extinct. In a new study, scientists have proposed that a sixth global extinction, about 10 million years before the End-Permian die-off, should be added to the list.

16 Jul 2015

Aquifers contaminated by Supertyphoon Haiyan storm surge

Supertyphoon Haiyan, which battered the Philippines in November 2013, was the most powerful hurricane to make landfall ever recorded. A new study has quantified damage done by the resulting storm surge to the fragile coastal aquifers that residents of one town rely on, and how long it might take for the aquifers to recover.

09 Jul 2015

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