Sentences with word «geodynamo»

According to the study, which is based on three - dimensional simulations of geodynamos created by turbulent liquids and models of Earth's thermal history, the inner core is believed to have begun solidifying roughly 650 million years ago.

Motion of the earth's liquid core, the so - called geodynamo, generates its magnetic field.

The hope is to get a lab - size geodynamo going under small - scale conditions that mimic those inside Earth.

Scientists believe that Mars had an active geodynamo when that planet was formed, but that it died off after four billion years.

Scientists in the area of paleomagnetism use magnetic minerals to investigate the history of the earth's magnetic field and its formation from molten metal flowing within the earth's core, the so - called geodynamo.

Were it not for that store of excess heat, Earth's geodynamo might never have started.

Those fields in turn give rise to more electric currents, an effect that results in a self - sustaining cycle called a geodynamo.

This so - called compositional convection would be another way to power the geodynamo.

Evidence from ancient rocks reveals that Earth's geodynamo has been up and running for at least 3.5 billion years.

Protoplanet collisions with a young Earth may have led to the birth of our moon and could have kick - started the geodynamo that makes life here possible.

But here is the fundamental problem with our understanding of the geodynamo: It can't work in the way geophysicists have long believed.

Stevenson, Buffett and other researchers suspect that the theory of the moon's fiery birth might also solve the problem of how Earth kept its geodynamo running before the inner core formed: Much of the impact energy of primordial collisions, like the one that may have caused the moon to form, would have been converted into heat, liquefying Earth's interior.

One of the leading explanations would have beggared the imaginations of even the most inventive medieval mapmakers: Primordial collisions between the young Earth and other protoplanets forced mantle material into the core, providing the heat that kick - started Earth's geodynamo.

How did the geodynamo manage to function for at least a couple of billion years before the inner core existed?

We would not have a geodynamo without convection.»

«This is a big problem,» Alfè says, «because convection is what drives the geodynamo.

The swirling motions of the liquid metals there create the conditions for what is known as a geodynamo — a geologic electric generator.

The intensity measurements reveal a great deal about the presence of a geodynamo at the Earth's core.

A lab at the École Normale Supérieure in Paris has created a geodynamo in this way, and the scientists there were able to observe flips in polarity, although critics say that the experiment does not replicate the core's conditions closely enough to be trumpeted as a true success.

Lathrop is building a 10 - foot - sphere version of this kind of experiment that some believe will be the first model to convincingly imitate Earth's geodynamo.

Since neither the Earth's rotation around its axis, nor the direction of its axis, nor the Moon's orbit are perfectly regular, their combined effect on motion in the core is unstable and can cause fluctuations in the geodynamo.

T, indicating the presence of a geodynamo at the core of the planet, as well as suggesting the existence of the plate tectonics needed to release the built - up heat.

For the geodynamo to work, the Earth would have had to be totally molten four billion years ago, and its core would have had to slowly cool from around 6800 °C at that time to 3800 °C today.

This shield is produced by the geodynamo, the rapid motion of huge quantities of liquid iron alloy in the Earth's outer core.

Earth's magnetic field is generated in its liquid iron core, and this «geodynamo» requires a regular release of heat from the planet to operate.

The action of the Moon, overlooked until now, is thought to have compensated for this difference and kept the geodynamo active.

«These thermal variations also have profound implications for the geodynamo in the core, which creates Earth's magnetic field.»

The motion of liquid iron in Earth's outer core drives a phenomenon called the geodynamo, which creates Earth's magnetic field.

A team of researchers, led by Prof. Alessandro Toschi and Prof. Karsten Held (TU Wien) and Prof. Giorgio Sangiovanni (Würzburg University) has now published calculations in the journal «Nature Communications,» which show that the theory of the geodynamo has to be revised.

«Nickel is crucial for Earth's magnetic field: Scientists are changing our idea of the Earth's magnetic field: iron alone can not explain the concept of the geodynamo.»

These currents generate electric currents which create the magnetic field in a natural process known as a geodynamo.

Then, shortly after the predicted timing of the core solidification event nearly 650 million years ago, the geodynamo simulations predict that Earth's magnetic field transitioned back to a two - pole system.

Knowledge about past geomagnetic field variations on centennial to millennial scales is not only important to gain better understanding of the geodynamo process in the Earth's core, but also to estimate the geomagnetic shielding effect against galactic cosmic rays in space climate studies.

Most attractively, they allow for upward and downward continuation within source - free regions, specifically to the top of the Earth's core and thus provide information about the geodynamo process.

Reconstructions of the geomagnetic field in the past represent a useful tool not only to investigate the geodynamo process, but also to estimate the effect of geomagnetic shielding for any studies on cosmogenic radionuclides and galactic cosmic rays.