... Click here to go to index) . Ever since the launch of the first Sputnik in 1957, space exploration has advanced on two fronts, manned and unmanned . ... It includes: . The magnetosphere , the region dominated by the Earth's magnetic field. ... It includes a quick overview of the relevant physical sciences--magnetism, ions and electrons, plasmas etc.--and also includes tidbits of history, accessible by a "history button" at the ends of many sections. ... Electrons, Ions and Plasmas. ...
... Files in red?history) . ... Positive Ions . ... In the 19th century it was well known that water in which salts were dissolved (or acids, or bases) conducted electricity, and that an electric current could separate such dissolved materials into their components. ... In 1898 Ernest Rutherford noted that the radiation seemed to contain two electrically charged components of opposite signs, steered by a magnet in opposite directions--positive "alpha rays" and negative "beta rays." ...
Triton . Neptune I . ... Voyager 2 images showed active geyser-like eruptions spewing nitrogen gas and dark dust particles several kilometers into the atmosphere. ... Voyager 2 obtained this color image of Neptune's large satellite Triton during its close flyby on Aug. ... The polar frosts were sublimating because Triton's orbital and rotational motion causes the sun to shine directly on the polar cap for a period of several decades during Neptune's and Triton's long austral summer. ...