Which is the Earth's only natural satellite?
26 Nov 06
The Moon is the Earth's sole companion, orbiting at an average distance of 384,400km. It follows us on our path around the Sun, making one orbit of us (as seen against the background of stars) every 27 days, 7 hours, 43 minutes. This period is referred to as the sidereal month. The Moon's equatorial diameter measures 3,476km making it less than one third the diameter of the Earth. Eclipses As the orbital plane of the Moon lies within 5° of the apparent orbit of the Sun as seen from Earth, occasionally their positions in the sky coincide, giving rise to a solar eclipse. The photo above shows the shadow cast by the moon - around 100 km across it moves at over mach 2! Solar Eclipses At other times the Moon's orbit takes it into the shadow cast by the Earth into space, causing a lunar eclipse. Unlike solar eclipses, Lunar eclipses are readily observed from large areas of the Earth's surface, due to the greater extent of the Earth's shadow than that of the Moon's. Map of the Moon Philip's do a large map of the Earth-facing side of the Moon with over 500 named features plus the landing sites of spacecraft. It's perfect for any classroom wall, or even for serious observations. source : harmsy.freeuk.com
26 Nov 06
that would be the moon. The Moon is Earth's only natural satellite. It has no formal English name other than "the Moon", although it is occasionally called Luna (Latin: moon), or Selene (Greek: moon), to distinguish it from the generic term "moon" (referring to any of the various natural satellites of other planets). Its symbol is a crescent (?). The related adjective for the Moon is lunar (again from the Latin root), but this is not found in combination with the forms seleno-/-selene (again from the Greek) and -cynthion (from the Lunar deity Cynthia). from the site http://www.wikipedia.org greetings. : )