... 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. ...

... Ever since the launch of the first Sputnik in 1957, space exploration has advanced on two fronts, manned and unmanned . ... 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. ... Close-up of the Aurora. ... History Button . ... Exploration" home page (index) Glossary ....

Mathilde . ... On June 27, 1997 the Near-Earth Asteroid Rendezvous (NEAR) spacecraft flew flew past asteroid 253 Mathilde. ... On June 27, 1997 NEAR made a spectatular 25 minute flyby of Mathilde which resulted in more than 500 images of a dark, crater-battered little world that dates to the beginning of the solar system. ... This first image of asteroid 253 Mathilde, returned by the NEAR spacecraft just before 10:00 AM EDT on June 27, 1997, was taken from a distance of 1800 kilometers (1120 miles). ...