Skip to main content Accessibility help

We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.

Close cookie message
×
Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-05T10:32:41.014Z Has data issue: false hasContentIssue false

Chapter 14 - The Terrestrial Magnetosphere

Published online by Cambridge University Press:  22 October 2009

Tamas I. Gombosi
Tamas I. Gombosi
Affiliation:
University of Michigan, Ann Arbor
Get access

Summary

The terrestrial magnetosphere comprises the region of space where the properties of naturally occurring ionized gases are controlled by the presence of Earth's magnetic field. This very broad definition means that the terrestrial magnetosphere extends from the bottom of the ionosphere to more than ten Earth radii (Re) in the sunward direction and to several hundred Re in the antisunward direction.

The magnetosphere is formed as a result of the interaction of the supersonic, superalfvénic, magnetized solar wind with the intrinsic magnetic field of the Earth. To understand this interaction, we first briefly discuss the main characteristics of the intrinsic terrestrial magnetic field and then turn our attention to the interaction between this intrinsic field and the solar wind.

The Intrinsic Magnetic Field

A couple of hundred years ago Gauss showed that the magnetic field at the surface of the Earth can be described as the gradient of a scalar potential. In general the near Earth magnetic field can be expressed as

where Φint and Φext represent scalar potentials due to intrinsic and external sources, and Φtot is the sum of these two potentials (describing the total geomagnetic field). In general, planetary magnetic potentials are expressed as an infinite series using associated Legendre polynomials:

where θ and ϕ are geographic colatitude and east longitude, respectively.

Type
Chapter
Information
Physics of the Space Environment , pp. 278 - 314
Publisher: Cambridge University Press
Print publication year: 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Save book to Kindle

To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×