NOTE: "The Exploration of the Earth's Magnetosphere" is now available via FTP as a TARed and GZIPed file (4.7 MB) for unix machines. For details, see Resources file.
Click here for a full version (124K) of this image.
Ever since the launch of the first Sputnik in 1957, space exploration has
advanced on two fronts, manned and unmanned. The manned missions are well
known--from Mercury, Gemini and Apollo, to the Space Shuttle and the proposed
Space Station Freedom. Millions have watched "Apollo 13" or "The Right Stuff." In contrast, the exploration of space by unmanned spacecraft has remained almost invisible. The world applauded in 1958, when Explorers 1 and 3 discovered the radiation belt, but the many missions which followed are virtually unknown. Here is a glimpse of that other side of the space adventure. It includes: -- The magnetosphere, the region dominated by the Earth's magnetic field. Here energetic particles are trapped and fast electrons are produced; some are sent down into the atmosphere to produce the polar aurora or "northern and southern lights." Unmanned probes also discovered magnetospheres around Jupiter, Saturn, Uranus and Neptune. -- The fast solar wind, flowing out of the Sun in all directions, hemming in the Earth's magnetosphere while supplying energy to the aurora and to other geospace phenomena. -- The many types of high energy particles found in space, produced near Earth, at the Sun and in distant stars. The universe seems surprisingly rich in such particles, and we are only beginning to understand why. -- The complex flow of plasmas in space, of gases consisting of free electrons and of electrically charged atoms missing one or more electrons ("ions"). Most of the known universe consists of plasma, and the magnetosphere is our best laboratory for studying its plasma processes. "The Exploration of the Earth's Magnetosphere" is meant to give you, the reader and browser, a brief tour of this strange and fascinating new world. The tour is non-mathematical but fairly detailed. Main topics are described in the 8 files below, and from there more detailed descriptions branch out. Many detailed sections also have a history button at the end, leading to additional material: the button at the end of this section, for instance, brings up a brief chronology of magnetospheric physics and related fields. One aspect underscored by history is the international scope of space research, uniting Americans, Russians, Britons, Frenchmen, Japanese, Scandinavians, Germans, Canadians and others in a common endeavor. Electricity and magnetism play key roles in space research. This tour therefore includes brief primers on their place in space phenomena, as well as on the study of ions and electrons. Collectively they are probably equivalent to an easy freshman course, of the type that might be called "Space Science for Poets." Illustrations are deliberately kept small to reduce loading time. The index provides the fastest overview and access to all files in the collection: you can link to it An here or at the end of any file. "Exploration" also contains many outside links , e.g. to home pages of ongoing space missions; many such links can also be reached from URLs at the end of the section Additional Resources, along with other information. The end of this home page is linked to a list of questions from users, with answers, as well as three articles related to the material. The main divisions of "The Exploration of the Earth's Magnetosphere" can be accessed below:
2. Electrons, Ions and Plasmas. 4. The Sun and the Solar Wind. 8. Magnetospheres and the Universe.
The authors, both scientists engaged in magnetospheric physics, would greatly appreciate comments by users. Please tell us what you have found useful and what was difficult, unclear or (worse) inaccurate. Any suggestions for changes, additions or for new links would be most welcome. You may also send e-mail to the authors (see below).
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"Exploration" home page ......... "Exploration" index
Author and Curator: Dr. David P. Stern
Mail to Dr.Stern: education("at" symbol)phy6.org
Co-author: Dr. Mauricio Peredo
Last updated: November 26, 1996