... Spanish translation of "Stargazers" by J. M. Mendez and Horacio Chavez . ... Astronomy of the Earth's motion in space: . ... The Path of the Sun, the Ecliptic . ... 4b. Optional: Libration of the Moon . ... Kepler's 3 Laws of Planetary Motion ," a one-hour overview lecture to teachers presented 23 March 2005. Guide to the sections on Kepler's Laws which follow below. ... 11a. Ellipses and Kepler's First Law . ... Kepler's Second Law . 12a. More on Kepler's Second Law . ... Kepler's Third Law . ...

... Perhaps the most interesting satellites in this group are the ones sent into distant orbits, some of them extending well past the Moon--e.g. the WIND spacecraft pictured here. Among them is a long series of IMP s (Interplanetary Monitoring Platforms) which sampled the Earth's distant magnetic environment, the magnetosphere, and the surrounding interplanetary region; IMP-8 is still returning good data, more than 20 years after its launch. ...

Titan . ... Hubble Space Telescope Images of Titan's surface . ... Later that year, it will release the European-built Huygens probe for a descent through Titan's atmosphere. ... This artist's rendering shows the European Space Agency's Huygens probe descending into the atmosphere of Saturn's moon Titan after being released by NASA's Cassini spacecraft. ... This artist's rendering shows the Huygens probe on the surface of Saturn's moon Titan after being released by NASA's Cassini spacecraft. ...