With its thick, hazy atmosphere and surface rivers, mountains, lakes and dunes, Titan, Saturn’s largest moon, is one of the most Earth-like places in the solar system. As the Cassini-Huygens spacecraft examines Titan over many years, its discoveries bring new mysteries. One of those involves the seemingly wind-created sand dunes spotted by Cassini near the moon’s equator, and the contrary winds just above.
While no one yet knows what's needed to build a habitable planet, it's clear that the interplay...
Within the first 150 million years after our solar system formed, a giant body roughly the size...
The Pacific Northwest is dotted by small, low-lying, coastal cities where populations tend to cluster. These communities can be isolated and are susceptible to devastation from major storms that bring substantial wind, waves and storm surge. With climate change, it is anticipated that storms will only become more frequent and intense, signifying a need to understand how the areas will be affected.
An international research team, led by a Virginia Tech geoscientist, has revealed information about how continents were generated on Earth more than 2.5 billion years ago, and how those processes have continued within the last 70 million years to profoundly affect the planet's life and climate.
To understand when and why volcanoes erupt, scientists study the rocks left behind by eruptions past. A method called geobarometry uses the composition of volcanic rocks to estimate the pressure and depth at which molten magma was stored just before it erupted. A research team has tested a new type of geobarometer that is well-suited to study the kind of magma often produced in explosive and destructive volcanic eruptions.
A team of scientists has a new explanation for the planet Mercury’s dark, barely reflective surface. In a paper published in Nature Geoscience, the researchers suggest that a steady dusting of carbon from passing comets has slowly painted Mercury black over billions of years.
Researchers from Brown Univ. have completed a new analysis of an ancient Martian lake system in Jezero Crater, near the planet’s equator. The study finds that the onslaught of water that filled the crater was one of at least two separate periods of water activity in the region surrounding Jezero.
Lava tubes large enough to house cities could be structurally stable on the moon, according to a theoretical study. The volcanic features are an important target for future human space exploration because they could provide shelter from cosmic radiation, meteorite impacts and temperature extremes.
A Carnegie Institute-led team was able to discover five new forms of silica under extreme pressures at room temperature. Silica is one of the most-abundant natural compounds and a major component of the Earth's crust and mantle. It is well-known even to non-scientists in its quartz crystalline form, which is a major component of sand in many places. It is used in the manufacture of microchips, cement, glass and even some toothpaste.
Researchers at Sandia National Laboratories’ Z machine have helped untangle a long-standing mystery of astrophysics: Why iron is found spattered throughout Earth’s mantle, the roughly 2,000-mile thick region between Earth’s core and its crust.
A research group in the Univ. of Arizona Lunar and Planetary Laboratory has found evidence in meteorites that hint at the discovery of a previously unknown region within the swirling disk of dust and gas known as the protoplanetary disk, which gave rise to the planets in our solar system.
New modeling and analyses of fault geometry in the Earth's crust by geoscientist Michele Cooke and colleagues at the Univ. of Massachusetts Amherst are advancing knowledge about fault development in regions where one geologic plate slides past or over another, such as along California's San Andreas Fault and the Denali Fault in central Alaska.
Two new papers from members of the MESSENGER Science Team provide global-scale maps of Mercury’s surface chemistry that reveal previously unrecognized geochemical terranes, large regions that have compositions distinct from their surroundings. The presence of these large terranes has important implications for the history of the planet.
As everyone who lives in the San Francisco Bay Area knows, the Earth moves under our feet. But what about the stresses that cause earthquakes? How much is known about them? Until now, our understanding of these stresses has been based on macroscopic approximations.
Violent collisions between the growing Earth and other objects in the solar system generated significant amounts of iron vapor, according to a new study by Lawrence Livermore National Laboratory. The results show that iron vaporizes easily during impact events, which forces planetary scientists to change how they think about the growth of planets and evolution of our solar system.
The activity of the sun is an important factor in the complex interaction that controls our climate. New research now shows the impact of the sun isn’t constant over time, but has greater significance when the Earth is cooler. There has been much discussion as to whether variations in the strength of the sun have played a role in triggering climate change in the past.
Geysers like Old Faithful in Yellowstone National Park erupt periodically because of loops or side-chambers in their underground plumbing, according to recent studies by volcanologists at the Univ. of California, Berkeley. The key to geysers is an underground bend or loop that traps steam and then bubbles it out slowly to heat the water column above until it is just short of boiling.
Sea levels from New York to Newfoundland jumped up about four inches in 2009 and 2010 because ocean circulation changed, a Univ. of Arizona-led team reports in Nature Communications. The team was the first to document that the extreme increase in sea level lasted two years, not just a few months.
Engineers have completed one of the most precise evaluations yet about the impact of a major tsunami event on the Columbia River. They found what forces are most important in controlling water flow and what areas might be inundated.
At least five mass extinction events have profoundly changed the history of life on Earth. But a new study led by researchers at the Univ. of Gothenburg shows that plants have been very resilient to those events. For over 400 million years, plants have played an essential role in almost all terrestrial environments and covered most of the world's surface.
A spark from a lightning bolt, interstellar dust or a subsea volcano could have triggered the very first life on Earth. But what happened next? Life can exist without oxygen; but without plentiful nitrogen to build genes, life on the early Earth would have been scarce. The ability to use atmospheric nitrogen to support more widespread life was thought to have appeared roughly 2 billion years ago.
Pioneering techniques that use satellites to monitor ocean acidification are set to revolutionize the way that marine biologists and climate scientists study the ocean. This new approach, published in Environmental Science and Technology, offers remote monitoring of large swathes of inaccessible ocean from satellites that orbit the Earth some 700 km above our heads.
New techniques are allowing scientists to understand how carbon dioxide, released from the deep ocean, helped to end the last ice age and create our current climate. An international team studied the shells of ancient marine organisms that lived in surface waters of the southern Atlantic and eastern equatorial Pacific oceans thousands of years ago.
Deep cuts in greenhouse gas emissions, while necessary, may not happen soon enough to stave off climate catastrophe. So, in addition, the world may need to resort to so-called geoengineering approaches that aim to deliberately control the planet's climate. That's according to a National Research Council committee that released a pair of sweeping reports on climate intervention techniques.
Seismic waves are helping scientists to plumb the world’s deepest mystery: the planet’s inner core. Thanks to a novel application of earthquake-reading technology, a research team at the Univ. of Illinois and colleagues at Nanjing Univ. in China have found that the Earth’s inner core has an inner core of its own, which has surprising properties that could reveal information about our planet.
A team of Carnegie Institute scientists have found “beautifully preserved” 15-million-year-old thin protein sheets in fossil shells from southern Maryland. The team collected samples from Calvert Cliffs, along the shoreline of the Chesapeake Bay, a popular fossil collecting area. They found fossilized shells of a snail-like mollusk called Ecphora that lived in the mid-Miocene era.
NWA 7034, a meteorite found a few years ago in the Moroccan desert, is like no other rock ever found on Earth. It’s been shown to be a 4.4 billion-year-old chunk of the Martian crust, and according to a new analysis, rocks just like it may cover vast swaths of Mars.
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