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.
LRO and LCROSS were launched together on the same rocket in June 2009. LRO maps the Moon from lunar orbit. LCROSS crashes (on purpose!) 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 from Florida in June 2009. The two spacecraft were launched together on one rocket.
LRO stands for "Lunar Reconnaissance Orbiter". LRO is in orbit around the Moon. It is taking very detailed pictures of the Moon's surface. These pictures will be used to make a better new map of the Moon. That map will help scientists plan other Moon missions that are coming up in the next few years. LRO is also searching for signs of water ice near the Moon's North and South Poles. LRO is also studying radiation near the Moon. That will be important to know about when astronauts go back to the Moon.
LCROSS stands for Lunar CRater Observation and Sensing Satellite. LCROSS will crash into the Moon on purpose! It will hit the Moon near the South Pole on October 9, 2009. LCROSS is trying 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 a crater near the South Pole. Scientists think there might be water ice in that crater. The crash will create a large plume of material when the Centaur explodes upon impact. LCROSS will use instruments to search for signs of water molecules within the plume. The LCROSS spacecraft will also smash into the Moon soon after the Centaur rocket. Telescopes on Earth will watch both crashes.
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