Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. 24/7 Space News .




EXO WORLDS
Magnesium oxide: From Earth to super-Earth
by Staff Writers
Washington DC (SPX) Nov 27, 2012


File image.

The mantles of Earth and other rocky planets are rich in magnesium and oxygen. Due to its simplicity, the mineral magnesium oxide is a good model for studying the nature of planetary interiors. New work from a team led by Carnegie's Stewart McWilliams studied how magnesium oxide behaves under the extreme conditions deep within planets and found evidence that alters our understanding of planetary evolution.

Magnesium oxide is particularly resistant to changes when under intense pressures and temperatures.

Theoretical predictions claim that it has just three unique states with different structures and properties present under planetary conditions: solid under ambient conditions (such as on the Earth's surface), liquid at high temperatures, and another structure of the solid at high pressure. The latter structure has never been observed in nature or in experiments.

McWilliams and his team observed magnesium oxide between pressures of about 3 million times normal atmospheric pressure (0.3 terapascals) to 14 million times atmospheric pressure (1.4 terapascals) and at temperatures reaching as high as 90,000 degrees Fahrenheit (50,000 Kelvin), conditions that range from those at the center of our Earth to those of large exo-planet super-Earths.

Their observations indicate substantial changes in molecular bonding as the magnesium oxide responds to these various conditions, including a transformation to a new high-pressure solid phase.

In fact, when melting, there are signs that magnesium oxide changes from an electrically insulating material like quartz (meaning that electrons do not flow easily) to a metal similar to iron (meaning that electrons do flow easily through the material).

Drawing from these and other recent observations, the team concluded that while magnesium oxide is solid and non-conductive under conditions found on Earth in the present day, the early Earth's magma ocean might have been able to generate a magnetic field.

Likewise, the metallic, liquid phase of magnesium oxide can exist today in the deep mantles of super-Earth planets, as can the newly observed solid phase.

"Our findings blur the line between traditional definitions of mantle and core material and provide a path for understanding how young or hot planets can generate and sustain magnetic fields," McWilliams said.

"This pioneering study takes advantage of new laser techniques to explore the nature of the materials that comprise the wide array of planets being discovered outside of our Solar System," said Russell Hemley, director of Carnegie's Geophysical Laboratory.

"These methods allow investigations of the behavior of these materials at pressures and temperatures never before explored experimentally."

The experiments were carried out at the Omega Laser Facility of the University of Rochester, which is supported by DOE/NASA. The research involved a team of scientists from University of California Berkley and Lawrence Livermore National Laboratory.

This paper was published November 22 by Science Express.

.


Related Links
Omega Laser Facility
Carnegie Institution
Lands Beyond Beyond - extra solar planets - news and science
Life Beyond Earth






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





EXO WORLDS
NASA's Kepler Wraps Prime Mission, Begins Extension
Pasadena CA (JPL) Nov 20, 2012
NASA is marking two milestones in the search for planets like Earth; the successful completion of the Kepler Space Telescope's three-and-a-half-year prime mission and the beginning of an extended mission that could last as long as four years. Scientists have used Kepler data to identify more than 2,300 planet candidates and confirm more than 100 planets. Kepler is teaching us that the gala ... read more


EXO WORLDS
China's Chang'e-3 to land on moon next year

Moon crater yields impact clues

Study: Moon basin formed by giant impact

NASA's LADEE Spacecraft Gets Final Science Instrument Installed

EXO WORLDS
Fostering Curiosity: Mars Express relays rocky images

Matijevic Hill Survey Complete And Rover Passes 22 Miles Of Driving!

NASA monitors massive dust storm on Mars

Intrigue from Mars, or Grotzinger's silence

EXO WORLDS
Who's Killing the Space Program?

Fly me to the universe

UK Secures Billion Pound Package For Space Investment

Europe, U.S. talk space program link

EXO WORLDS
Mr Xi in Space

China plans manned space launch in 2013: state media

China to launch manned spacecraft

Tiangong 1 Parked And Waiting As Shenzhou 10 Mission Prep Continues

EXO WORLDS
Three ISS crew return to Earth in Russian capsule

Station Crew Off Duty After Undocking

Space station command changes

Russia restores space contact after cable rupture

EXO WORLDS
Failure Of India's Big Rocket Project Is Symbolic Of Deep Structural Problems

Russian Briz-M puts US satellite into orbit

Pleiades 1B is ready for integration in the payload "stack" for Arianespace's next Soyuz mission

France, Germany compromise on Ariane launcher: minister

EXO WORLDS
Magnesium oxide: From Earth to super-Earth

Rare image of Super-Jupiter sheds light on planet formation

Astronomers Directly Image Massive Star's 'Super-Jupiter'

NASA's Kepler Wraps Prime Mission, Begins Extension

EXO WORLDS
Japan firm offers 3D model of foetus

Modeling the breaking points of metallic glasses

Putting more cores to work in server farms

New device hides, on cue, from infrared cameras




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement