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The scans for MH370 revealed that the ocean crust rises and falls in waves that start at the Southeast Indian Ridge and continue outward. The ridge spreads about 35 millimeters in opposite directions every year, and the wave crests, where crust grew faster, are more than 100 kilometers long and repeat every 10-14 kilometers. The researchers estimated when each wave formed by comparing the bathymetry maps to independent measurements and models of the crust's magnetic field. ...Crustal rocks record the polarity of Earth's magnetic field as they form, allowing scientists to trace the age of different sections of ocean crust....

Earthquakes generate seismic waves below Earth's surface that travel thousands of miles. When the waves encounter changes in rock density, temperature or composition, they change speed, bend or scatter, producing echoes that can be detected. Echoes from nearby structures arrive more quickly, while those from larger structures are louder. By measuring the travel time and amplitude of these echoes as they arrive at seismometers in different locations, scientists can develop models of the physical properties of rock hidden below the surface. This process is similar to the way bats echolocate to map their environment Using a machine learning algorithm called...

Lambart and her colleagues from Wales and the Netherlands, sought to discover what the mantle looks like before it rises as lava at a mid-ocean ridge. They examined cores, drilled through the ocean crust, to look at cumulate minerals: the first minerals to crystallize when the magmas enter the crust. They analyzed the samples centimeter by centimeter to look at variations in isotopes of neodymium and strontium, which can indicate different chemistries of mantle material that come from different types of rock. The amount of isotope variability in the cumulates was seven times greater than that in the mid-ocean ridge...

The Earth has a second magnetic field, one generated by ocean currents. Researchers know little about it, but images captured by satellites show this invisible force generated by the world’s salty oceans in perfect detail. ... ESA released a video detailing the changes in the Earth’s magnetic field over a 24-hour period... ...“It’s a really tiny magnetic field. It’s about 2-2.5 nanotesla at satellite altitude, which is about 20,000 times weaker than the Earth’s global magnetic field.”... Oceans may have a small contribution to the magnetic field that protects the planet from harmful cosmic rays, but it remains to be...

The reason that the ocean floor, especially the southern hemisphere oceans, is so poorly charted is that electromagnetic waves cannot penetrate the deep ocean (3-5 km = 2-3 mi). Instead, depths are commonly measured by timing the two-way travel time of an acoustic pulse. However because research vessels travel quite slowly (6m/s = 12 knots) it would take approximately 125 years to chart the ocean basins using the latest swath-mapping tools. To date, only a small fraction of the sea floor has been charted by ships. Fortunately, such a major mapping program is largely unnecessary because the ocean surface has...

If you venture too close to one of Earth's poles, you'll notice something rather strange happening to any gadgets using radio waves, satellite connections, or GPS. NASA is backing a range of initiatives to investigate the northern polar cusp, a funnel in space that's thought to be behind some of the weird space phenomena happening above the poles. This funnel, and the matching one at the South Pole, allows solar winds from the Sun to get right down to Earth's atmosphere – in other words, here the solar winds aren't reflected back out into space by the Earth's magnetic field,...

The processes that led to glaciation at the cratered poles of Mercury, the planet closest to the sun, have been modeled by a University of Maine-led research team. James Fastook, a UMaine professor of computer science and Climate Change Institute researcher, and James Head and Ariel Deutsch of Brown University, studied the accumulation and flow of ice on Mercury, and how the glacial deposits on the smallest planet in our solar system compare to those on Earth and Mars.Their findings, published in the journal Icarus, add to our understanding of how Mercury's ice accumulations—estimated to be less than 50 million...

One of the Moon's biggest craters was created by an asteroid more than 250km (150 miles) across, a study suggests. It smashed into the lunar surface about 3.8 billion years ago, forming Mare Imbrium - the feature also known as the right eye of the "Man in the Moon". Scientists say the asteroid was three times bigger than previously estimated and debris from the collision would have rained down on the Earth. The asteroid was so big it could be classified as a protoplanet - a space rock with the potential to become a fully formed world. Lead author Prof...

Explanation: What's that under the surface of Mercury? The robotic MESSENGER spacecraft that had been orbiting planet Mercury for the past four years had been transmitting its data back to Earth with radio waves of very precise energy. The planet's gravity, however, slightly changed this energy when measured on Earth, which enabled the reconstruction of a gravity map of unprecedented precision. Here gravitational anomalies are shown in false-color, superposed on an image of the planet's cratered surface. Red hues indicate areas of slightly higher gravity, which in turn indicates areas that must have unusually dense matter under the surface. The...

At first glance it looks like a potato-shaped asteroid flying through space. But this multi-coloured image is actually the Earth - and shows how gravity varies on different parts of the globe. The images were unveiled today by the team behind the GOCE satellite at a conference in Munich and are the most accurate ever released. The 'geoid' map, as it is known, is used to illustrate how oceans would look in the absence of currents or tides. The bright yellow colours show gravity at its strongest, while it is at its weakest in the blue areas. There appears to...

Explanation: Why do some places on Earth have higher gravity than others? Sometimes the reason is unknown. To help better understand the Earth's surface, sensitive measurments by the orbiting satellites GRACE and CHAMP were used to create a map of Earth's gravitational field. Since a center for studying this data is in Potsdam, Germany, and since the result makes the Earth look somewhat like a potato, the resulting geoid has been referred to as the Potsdam Gravity Potato. High areas on this map, colored red, indicate areas where gravity is slightly stronger than usual, while in blue areas gravity is...

In trying to predict where earthquakes will occur, few people would think to look at Earth's gravity field. What does the force that causes objects to fall to the ground and the moon to orbit around the earth have to do with the unpredictable ground trembling of an earthquake? Now, researchers at the California Institute of Technology have found that within subduction zones, the regions where one of the earth's plates slips below another, areas where the attraction due to gravity is relatively high are less likely to experience large earthquakes than areas where the gravitational force is relatively low....

'Potato' Earth's deep secrets By Jonathan Amos BBC News Online science staff It is a map the like of which you have probably never seen before. Gravity highs are marked red; gravity lows are blue The sweep of colours shows minute variations in the Earth's gravitational field. If you were to fly over the red areas, you would be tugged ever so slightly downwards; the blues mark regions where the planet's attraction is much weaker. These gravity anomalies, as they are known, are imperceptible to the human senses, and so the scientists have wrapped the data on to a sphere...

Astronomy Picture of the Day 2001 November 13 A Gravity Map of Earth Credit: JPL, NASA Explanation: Is gravity the same over the surface of the Earth? No -- it turns out that in some places you will feel slightly heavier than others. The above relief map shows in exaggerated highs and lows where the gravitational field of Earth is relatively strong and weak. A low spot can be seen just off the coast of India, while a relative high occurs in the South Pacific Ocean. The cause of these irregularities is unknown since present surface features do not ...

Gravity highs (red) and lows (blue) on the Moon (Lunar nearside right, farside left)Science Results from the Japanese space agency's SELENE mission to the Moon are revealing details about why the lopsided lump of rock orbiting Earth is so unbalanced.The SELENE (Selenological and Engineering Explorer, or Kaguya) mission was launched in September 2007 to gather detailed geological information about the Moon. The results are published in Science1,2,3,4.Because the Moon has no atmosphere or weather to speak of, its geology has remained almost unchanged since it formed. So unpicking its structure could offer information about how the early Solar System —...

Does a giant crater lie beneath the Antarctic ice? Signs of an ancient impact could help to explain a mass extinction. Mark Peplow A dense bit of rock in the Antarctic (orange circle) seems to be circled by a crater. © Ohio State University Evidence of a cataclysmic meteorite impact has been unearthed in Antarctica, according to researchers who say the collision could possibly explain the greatest mass extinction ever seen on our planet. But scientists contacted by news@nature.com say they are sceptical, as no signs of such an enormous impact have been found in other, well-studied areas of Antarctica....