Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows
Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 degrees hotter than in a previous experiment run 20 years ago. These measurements confirm geophysical models that the temperature difference between the solid core and the mantle above, must be at least 1500 degrees to explain why the Earth has a magnetic field.
For more information about this study, see the press release from the European Synchrotron Radiation Facility.
Ocean Volcanic Rocks Contain Samples of Recycled Crust
Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials from the early Earth’s crust. But decisive evidence for this phenomenon has proven elusive. New research from a team including Carnegie’s Erik Hauri demonstrates that oceanic volcanic rocks contain samples of recycled crust dating back to the Archean era 2.5 billion years ago. Their work is published in Nature.
Oceanic crust sinks into the Earth’s mantle at so-called subduction zones, where two plates come together. Much of what happens to the crust during this journey is unknown. Model-dependent studies for how long subducted material can exist in the mantle are uncertain and evidence of very old crust returning to Earth’s surface via upwellings of magma has not been found until now.
For more information about these results, see the press release from the Carnegie Institution.
Launched together in June 2009, LRO and LCROSS both travelled to the Moon. LRO maps from lunar orbit, while LCROSS crashes near the South Pole. Images courtesy of NASA.
LRO and LCROSS are two space missions sent by NASA to Earth's Moon. LRO and LCROSS were launched together on an Atlas rocket from Cape Canaveral in Florida on June 18, 2009.
The Lunar Reconnaissance Orbiter (LRO) is a satellite that is now orbiting the Moon. LRO is mapping the Moon at very high resolution from a low orbit just 50 km (30 miles) above the lunar surface. These detailed maps will be used for planning of other upcoming robotic and human missions to the Moon. LRO is also searching for signs of water ice near the lunar poles and is studying radiation levels around the Moon, which will be important to know when astronauts return in the coming years.
The Lunar CRater Observation and Sensing Satellite (LCROSS) is designed to intentionally crash into the Moon on October 9, 2009. The goal of LCROSS is to detect signs of water ice in craters near the Moon's South Pole, if any is there. The Centaur upper stage of the rocket that launched LRO and LCROSS will crash into Cabeus crater, producing a huge plume of ejecta material. LCROSS will search for signs of water molecules within the ejecta cloud. Soon after the crash of the Centaur rocket, the LCROSS spacecraft will also smash into the Moon. Telescopes on Earth will observe both crashes.
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