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.
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Mercury has almost no atmosphere. The planet's small size means that its gravity is too weak to hold down a normal atmosphere. There is a very thin atmosphere around the planet. Mercury's thin atmosphere...more
Mercury is the only inner planet other than the Earth that has a significant magnetic field (220 nT). This field, along with the planet's high density and small size relative to the Earth, indicates that...more