Since 2006, when NASA’s Stardust spacecraft delivered its aerogel and aluminum foil dust collectors back to Earth, a team of scientists has combed through them. They now report finding seven dust motes that probably came from outside our solar system, perhaps created in a supernova explosion and altered by eons of exposure to the extremes of space. They would be the first confirmed samples of contemporary interstellar dust.
From research stations drifting on ice floes to high-tech aircraft radar, scientists have been tracking the depth of snow that accumulates on Arctic sea ice for almost a century. Now that people are more concerned than ever about what is happening at the poles, research led by the Univ. of Washington and NASA confirms that snow has thinned significantly in the Arctic, particularly on sea ice in western waters near Alaska.
The Jurassic and Cretaceous periods were the golden age of dinosaurs, during which the prehistoric giants roamed the Earth for nearly 135 million years. Paleontologists have unearthed numerous fossils from these periods, suggesting that dinosaurs were abundant throughout the world. But where and when dinosaurs first came into existence has been difficult to ascertain.
Turning what seemed like a science fiction tale into reality, an unmanned probe swung alongside a comet on Wednesday after a 4-billion mile chase through outer space over the course of a decade. Europe's Rosetta probe will orbit and study the giant lump of dust and ice as it hurtles toward the sun and, if all goes according to plan, drop a lander onto the comet in the coming months.
Aerosols, tiny particles in the atmosphere, play a significant role in Earth's climate, scattering and absorbing incoming sunlight and affecting the formation and properties of clouds. Currently, the effect that these aerosols have on clouds represents the largest uncertainty among all influences on climate change.
Scientists are searching through a massive collection of 20-million-year-old amber found in the Dominican Republic more than 50 years ago, and the effort is yielding fresh insights into ancient tropical insects and the world they inhabited. When the collection is fully curated, a task that will take many years, it will be the largest unbiased Dominican amber collection in the world, the researchers report.
As the climate warms and sea ice retreats, the North is changing. An ice-covered expanse now has a season of increasingly open water that is predicted to extend across the whole Arctic Ocean before the middle of this century. Storms thus have the potential to create Arctic swell. A Univ. of Washington researcher made the first study of waves in the middle of the Arctic Ocean, and detected house-sized waves during a September 2012 storm.
Reactions among minerals and organic compounds in hydrothermal environments are critical components of the Earth’s deep carbon cycle. They provide energy for the deep biosphere, and may have implications for the origins of life. However, very little is known about how minerals influence organic reactions. A team of researchers has demonstrated how a common mineral acts as a catalyst for specific hydrothermal organic reactions.
The U.S. Geological Survey plans this summer and next to map the outer limits of the continental shelf, and also study underwater landslides that would help predict where and when tsunamis might occur. But environmentalists say it could cause the same type of marine life damage they fought unsuccessfully to prevent this month off the coast of New Jersey.
Russian scientists say they believe a 66-yard wide crater discovered recently in far northern Siberia could be the result of changing temperatures in the region. Andrei Plekhanov, a senior researcher at the Scientific Research Center of the Arctic who visited the crater this week, the crater was mostly likely the result of a "build-up of excessive pressure" underground due to rising temperatures.
A 25-year-long study published in Geology provides the first quantitative measurement of in situ calcium-magnesium silicate mineral dissolution by ants, termites, tree roots, and bare ground. This study reveals that ants are one of the most powerful biological agents of mineral decay yet observed. This discovery might offer a line of research on how to "geoengineer" accelerated carbon dioxide consumption by Ca-Mg silicates.
Measuring the extreme pressures and temperatures of hydrothermal systems in the Earth's crust is no easy feat. However, Lawrence Livermore National Laboratory scientists have made a new tool that allows them to probe pressures up to 20 kbar (20,000 Earth atmospheres of pressure).
A decade of research by Rice Univ. scientists has produced a 2-D model to prove how gas hydrate, the “ice that burns,” is formed under the ocean floor. Gas hydrate has potential as a source of abundant energy, if it can be extracted and turned into usable form. It also has potential to do great harm.
Overturning conventional wisdom stretching all the way to Leonardo da Vinci, new research from Israel shows that how things break and how things slide are closely interrelated. The breakthrough study marks an important advance in understanding friction and fracture, with implications for describing the mechanics that drive earthquakes.
Processes that shaped the ridges and troughs on the surface of Jupiter's icy moon Ganymede are likely similar to tectonic processes seen on Earth, according to a team of researchers led by Southwest Research Institute. To arrive at this conclusion, the team subjected physical models made of clay to stretching forces that simulate tectonic action.
Researchers have developed a new design for the framework of columns and beams that support bridges, called "bents," to improve performance for better resistance to earthquakes, less damage and faster on-site construction. The faster construction is achieved by pre-fabricating the columns and beams off-site and shipping them to the site, where they are erected and connected quickly.
Tsunami earthquakes happen at relatively shallow depths in the ocean and are small in terms of their magnitude. However, they create very large tsunamis: just 5.6 on the Richter scale can produce a 10-m wave. New research reveals that tsunami earthquakes may be caused by extinct undersea volcanoes causing a “sticking point” between two sections of the Earth’s crust called tectonic plates, where one plate slides under another.
Superman isn't the only one who can see through solid surfaces. In a development that could revolutionize the management of precious groundwater around the world, Stanford Univ. researchers have pioneered the use of satellites to accurately measure levels of water stored hundreds of feet below ground.
Deep below the Earth's surface lies a thick, rocky layer called the mantle, which makes up the majority of our planet's volume. For decades, scientists have known that most of the lower mantle is a silicate mineral with a perovskite structure that is stable under the high-pressure and high-temperature conditions found in this region.
It’s likely that most of the large impact craters on Earth have already been discovered and that others have been erased, according to a new calculation by a pair of Purdue Univ. graduate students. Although it's known that natural processes erase craters fairly quickly from the Earth's surface, this model was the first to quantify how many craters have likely been erased.
A moderate earthquake shook northwest Alaska on Monday, the fifth temblor of the same magnitude since April in an area with otherwise little activity, seismologists said. The swarm of magnitude-5.7 quakes is connected to more than 300 smaller aftershocks, some with magnitudes in the high 3s, Ruppert said. The series of earthquakes has scientists puzzled about activity that is considered very unusual in the region of Noatak.
Beneath the barren whiteness of Greenland, a mysterious world has popped into view. Using ice-penetrating radar, researchers have discovered ragged blocks of ice as tall as city skyscrapers and as wide as the island of Manhattan at the bottom of the ice sheet, apparently formed as water beneath the ice refreezes and warps the surrounding ice upwards. The newly revealed forms may help scientists understand more about how ice sheets behave.
Researchers report evidence for an oceans worth of water deep beneath the U.S. Though not in the familiar liquid form—the ingredients for water are bound up in rock deep in the Earth’s mantle—the discovery may represent the planet’s largest water reservoir. The presence of liquid water on the surface is what makes our “blue planet” habitable, and scientists have tried to figure out just how much water may be cycling between Earth’s surface.
The slopes of a giant Martian volcano, once covered in glacial ice, may have been home to one of the most recent habitable environments yet found on the Red Planet, according to new research led by Brown Univ. geologists. Nearly twice as tall as Mount Everest, Arsia Mons is the third tallest volcano on Mars and one of the largest mountains in the solar system.
Researchers at the Univ. of Washington have concluded that Antarctica's fast-moving Thwaites Glacier will likely disappear in a matter of centuries, potentially raising sea level by more than a half a meter. Data gathered by airborne radar, detailed topography maps and computer modeling were used to make the determination. The fastest scenario based on the data, the researchers said, is 200 years, and the longest is more than 1,000 years.