Does the Earth carry a charge?

twofish-quant

If you just put two metals next to each other you won't get current. In order for you to get current you have to connect them with some sort of substance that allows ions to move in the other direction. This only works because the substance that moves charge through the fluid does so through bound electrons that move a lot less slowly then free electrons.

zonde

Let's compare two cases:
1) two different disconnected metals in electrolyte
2) two different connected metals in electrolyte

Ions in electrolyte move lot less slowly then electrons in metal. So that means that electron distribution in metals is stable compared to slowly moving ions (two dynamical processes are decoupled). As we observe that these two cases are different (stable) electron distribution should be different in two cases.

Dotini

Is Earth charged? Maybe, but what is the Earth? Does the Earth stop at the surface? We know from previous posts that the Earth's surface is negatively charged. Does the Earth include the troposphere, the ionosphere, the Van Allen belts, the magnetosphere? Is it smarter to think of the Earth as part of a dynamic system involving the sun and the interplanetary medium?

The following post will help us to think about these questions.

The lightning we are all familiar with is generated in clouds by charge separation and electric fields. http://www.sciencedaily.com/releases...0601140934.htm

Electrons are accelerated from Earth into the Van Allen belts:

When particularly intense lightning discharges in thunderstorms coincide with high-energy particles coming in from space (cosmic rays), nature provides the right conditions to form a giant particle accelerator above the thunderclouds.

The cosmic rays strip off electrons from air molecules and these electrons are accelerated upwards by the electric field of the lightning discharge. The free electrons and the lightning electric field then make up a natural particle accelerator.

The accelerated electrons then develop into a narrow particle beam which can propagate from the lowest level of the atmosphere (the troposphere), through the middle atmosphere and into near-Earth space, where the energetic electrons are trapped in the Earth's radiation belt and can eventually cause problems for orbiting satellites. These are energetic events and for the blink of an eye, the power of the electron beam can be as large as the power of a small nuclear power plant. http://www.sciencedaily.com/releases...0413202850.htm

Highly energetic electrons in the outer Van Allen belt are lost into the interplanetary medium during solar storms:

During powerful solar events such as coronal mass ejections, parts of the magnetized outer layers of sun's atmosphere crash onto Earth's magnetic field, triggering geomagnetic storms capable of damaging the electronics of orbiting spacecraft. These cosmic squalls have a peculiar effect on Earth's outer radiation belt, a doughnut-shaped region of space filled with electrons so energetic that they move at nearly the speed of light.

"During the onset of a geomagnetic storm, nearly all the electrons trapped within the radiation belt vanish, only to come back with a vengeance a few hours later," said Vassilis Angelopoulos, a UCLA professor of Earth and space sciences and IGPP researcher.

The missing electrons surprised scientists when the trend was first measured in the 1960s by instruments onboard the earliest spacecraft sent into orbit, said study co-author Yuri Shprits, a research geophysicist with the IGPP and the departments of Earth and space sciences, and atmospheric and oceanic sciences.

"It's a puzzling effect," he said. "Oceans on Earth do not suddenly lose most of their water, yet radiation belts filled with electrons can be rapidly depopulated."

Even stranger, the electrons go missing during the peak of a geomagnetic storm, a time when one might expect the radiation belt to be filled with energetic particles because of the extreme bombardment by the solar wind.

Where do the electrons go? This question has remained unresolved since the early 1960s. Some believed the electrons were lost to Earth's atmosphere, while others hypothesized that the electrons were not permanently lost at all but merely temporarily drained of energy so that they appeared absent.

"Our study in 2006 suggested that electrons may be, in fact, lost to the interplanetary medium and decelerated by moving outwards," Shprits said. "However, until recently, there was no definitive proof for this theory."

To resolve the mystery, Turner and his team used data from three networks of orbiting spacecraft positioned at different distances from Earth to catch the escaping electrons in the act. The data show that while a small amount of the missing energetic electrons did fall into the atmosphere, the vast majority were pushed away from the planet, stripped away from the radiation belt by the onslaught of solar wind particles during the heightened solar activity that generated the magnetic storm itself. http://www.sciencedaily.com/releases...0129150958.htm


The outer Van Allen belt swells and shrinks by a factor of 100 according to the way it fits into the larger system of its interaction with the solar wind and CMEs, and with Earth http://www.sciencedaily.com/releases...0131143745.htm

In reality, where do the extra energy and particles come from? Where do they disappear to, and what sends them on their way? How do these changes affect the rest of Earth's magnetic environment, the magnetosphere? We will find out with the RBSP mission. http://www.sciencedaily.com/releases...0717183418.htm



Respectfully submitted,
Steve