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Death Valley sliding stone mystery solved

The video above shows a famous sliding stone of Death Valley’s Racetrack Playa in motion. See it? It’s the big rock in the foreground. Watching this video, you become one of the first people on Earth to see a sliding stone in motion. Although their tracks across Racetrack Playa – a dry lake bed in Death Valley – have been observed and studied since the early 1900s, no one had ever seen the stones in motion … until now. What’s more, the researchers who captured this video say they now know what causes the stones to move.

Lava at Iceland volcano, with what’s left of Hurricane Cristobal

UPDATE SEPTEMBER 1, 2014 A considerable eruption occurred this weekend along the fissure that stretches to the northeast from Iceland’s Bárðarbunga volcano, currently the most-watched volcano in the world. The eruption was up to 50 times bigger than what occurred on Friday, August 29. GlacierHub reports:

At the Holuhraun lava field, lava has been erupting since Sunday morning. These lava fountains reach more than 50 meters high. Though they are dramatic, they do not release ash that would interfere with aviation. This activity is about five kilometers from Dyngjujökull Glacier. If the fissure opens under the glacier, floods might result.

Report: Summer ozone to get much worse in next 35 years

A new report warns of a 70% increase in the number of days with unhealthy summertime ozone levels by the year 2050.

Evidence for supernovas near Earth

A NASA sounding rocket has confirmed that the solar system is inside an ancient supernova remnant. Life on Earth survived despite the nearby blasts.

Testing a space rover under Alaskan ice

Scientists test a device on an Alaska glacier that could be used to explore an icy moon of Jupiter.

Researchers find life beneath half a mile of Antarctic ice

In a finding that could have implications in the search for life beyond Earth, researchers from an expedition called WISSARD confirmed this week that the waters and sediments of a lake that lies 800 meters (2,600 feet) beneath the surface of the West Antarctic ice sheet support “viable microbial ecosystems.”

Strange case of M82 X-1: A rare midsize black hole

Astronomers have used archival data from from an X-ray satellite to identify what they now believe is an unusual midsize black hole. We know of stellar black holes formed by dying stars; they are relatively small, measuring up to around 25 times the mass of our sun. And we know of supermassive black holes – now thought to reside in the cores of most galaxies – containing hundreds of thousands to billions of times the mass of the sun. But the black hole called M82 X-1 – the brightest X-ray source in the galaxy Messier 82, or M82, located 12 million light-years away – is thought to be around 400 times the sun’s mass. And that characteristic makes it very rare.

Intense rainbow over Northern Ireland

Glenn Miles Photography kindly contributed this beautiful photo.  See more photos by Glenn Miles

Glenn Miles Photography kindly contributed this beautiful photo. See more photos by Glenn Miles

New video of Pluto and giant moon Charon

NASA’s Pluto-bound New Horizons spacecraft created this new video of stills taken of the Pluto-Charon system over five days last month.

The Great Pacific Garbage Patch explained

How does ocean debris move around the Pacific Ocean? Where does it come from and how long has it been around? And what can we do about it?