. 24/7 Space News .
EXO WORLDS
Turbulence in planetary cores excited by tides
by Staff Writers
Paris, France (SPX) Jul 26, 2017


Left: simulation of a cubic parcel located in the liquid core of a planet disturbed by tidal effects. By focusing their electronic analysis on this reduced domain, researchers have accessed regimes similar to planetary regimes. The flow takes the shape of superimposed waves that interact non-linearly until forming three-dimensional wave inertia turbulence (see vertical vorticity field in the center), by contrast with models where flow becomes larger-scale turbulence structures aligned with the axis of rotation (see vertical vorticity field on the right).

Veritable shields against high-energy particles, planets' magnetic fields are produced by iron moving in their liquid core. Yet the dominant model for explaining this system does not fit the smallest celestial bodies. Researchers at the Institut de Recherche sur les Phenomenes Hors Equilibre and the University of Leeds have proposed a new model suggesting that turbulence in the liquid cores is due to tides produced by gravitational interactions between celestial bodies.

The model infers that instead of being due to large, turbulent molten iron vortices far from the surface, movements in the core are due to the superposition of many wave-type motions. This work was published in Physical Review Letters on July 21, 2017.

Scientists agree that magnetic fields form and remain due to iron flowing in the liquid core. Discussions become more complicated when they attempt to determine what allows these colossal masses to move. The dominant model is based on the slow cooling of celestial bodies, which causes convection, which in turn creates large vortices of molten iron parallel to the axis of rotation of the celestial body.

But small planets and moons cool too quickly for a magnetic field to be maintained there by convection several billions of years after they form. Researchers at IRPHE (CNRS/Aix Marseille Universite/Centrale Marseille) and the University of Leeds have now presented an alternative model where it is gravitational interactions between celestial bodies that disturb the core.

Tides, produced by these gravitational interactions, do indeed disturb the core periodically and amplify wave movements naturally present in the rotating liquid iron. This phenomenon ends up producing a completely turbulent flow, whose nature is not yet well understood.

To study this, researchers used an numerical model of a small parcel of a planetary core, rather than simulating the core as a whole, which would require too much calculation power. This approach allows fine characterization of the movements created in extreme geophysical regimes, while retaining the essential physical features.

The researchers have shown that turbulence is the result of the superimposition of a very high number of wave movements that permanently exchange energy. This specific state, called wave turbulence, can be seen as analogous in three dimensions to the movement of the ocean's surface, far from shores.

This work opens the path to new models that allow better understanding and prediction of the properties of the magnetic field of celestial bodies. This tidal model would apply to all orbiting bodies that are sufficiently disturbed by neighboring stars, planets or moons.

Research Report: Inertial wave turbulence driven by elliptical instability. Thomas Le Reun, Benjamin Favier, Adrian J. Barker, Michael Le Bars. Physical Review Letters, July 21, 2017.

EXO WORLDS
A New Search for Extrasolar Planets from the Arecibo Observatory
Arecibo PR (SPX) Jul 17, 2017
The National Science Foundation's Arecibo Observatory and the Planetary Habitability Laboratory of the University of Puerto Rico at Arecibo joined the Red Dots project using the ESO's exoplanet-hunter in the search for new planets around our nearest stars. This new collaboration will simultaneously observe in both the optical and radio spectrum Barnard's Star, a popular star in the science ... read more

Related Links
CNRS
Lands Beyond Beyond - extra solar planets - news and science
Life Beyond Earth


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


Comment using your Disqus, Facebook, Google or Twitter login.

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

EXO WORLDS
Soyuz rocket rolled out, ready to launch

Astronauts gear up for space with tough Russian training

Russian sanctions won't affect cooperation in space

NASA Offers Space Station as Catalyst for Discovery in Washington

EXO WORLDS
Vega to launch two Earth Observation Satellites for Italy, Israel and France

Three Up, Three Down as NASA Tests RS-25 Flight Controller

Iran in 'successful' test of satellite-launch rocket

Aerojet Rocketdyne's RS-25 Flight Controller Goes Three for Three in SLS Test

EXO WORLDS
Portals to new worlds: Martian exploration near the North Pole

For Moratorium on Sending Commands to Mars, Blame the Sun

Tributes to wetter times on Mars

Opportunity will spend three weeks at current location due to Solar Conjunction

EXO WORLDS
China develops sea launches to boost space commerce

Chinese satellite Zhongxing-9A enters preset orbit

Chinese Space Program: From Setback, to Manned Flights, to the Moon

Chinese Rocket Fizzles Out, Puts Other Launches on Hold

EXO WORLDS
Good Night, Lisa Pathfinder

A Final Farewell to LISA Pathfinder

ASTROSCALE Raises a Total of $25 Million in Series C Led by Private Companies

LISA Pathfinder: bake, rattle and roll

EXO WORLDS
Multitasking monolayers

Writing with the electron beam: Now in silver

Scientists announce the quest for high-index materials

A new synthesis route for alternative catalysts of noble metals

EXO WORLDS
SETI Institute-Unistellar Partnership Promises to Revolutionize Amateur Astronomy

Holographic imaging could sample and identify living microbes in the outer solar system

Why looking for aliens is good for society

Breakthrough Starshot launches tiny spacecraft in quest for Alpha Centauri

EXO WORLDS
New Horizons Video Soars over Pluto's Majestic Mountains and Icy Plains

Juno spots Jupiter's Great Red Spot

New evidence in support of the Planet Nine hypothesis

NASA's New Horizons Team Strikes Gold in Argentina









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news 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. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. 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. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.