The Blue Marble Antarctica Earth At Night This composite view of earth shows the global city lights as seen by the Defense Meteorological Satellite. Mosaic of the United States A mosaic of the United States prepared by using 16 images from the Advanced Very High Resolution Radiometer (AVHRR) sensors on the meteorological satellites NOAA-8 and NOAA-9. The images were acquired between May 24, 1984 and May 14, 1986. Earth Facts Third Planet from the Sun Diameter at the Equator 7,926 miles Equatorial circumference 24, 902.4 miles Distance from Sun 93 Million Miles Length of Day 24 Hours Revolution Period about the Sun 365 days 5 hrs Surface Temperature -128° F to 136° F Moons 1 (the Moon) Earth’s orbit The earth goes around the sun once each year while meanwhile rotating about its axis once each day. Earth Mythology Planetary Symbol Gaea, or Mother Earth, was the great goddess of the early Greeks. She represented the Earth and was worshipped as the universal mother. In Greek mythology, she created the Universe and gave birth to both the first race of gods (the Titans) and the first humans. Note: Earth is the only planet whose English name does not derive from Greek/Roman mythology. The name derives from Old English and Germanic. Journey to the Center of the Earth Earth's Layers (depths in km) The earth is divided into four main layers: the inner core, outer core, mantle, and crust. The Moon This full disc of the Moon was photographed by the Apollo 17 crew. The Moon is on average 238,857 miles from the Earth. Its diameter is 2,160 miles. Both the rotation of the Moon and its revolution around Earth takes 27 days, 7 hours, and 43 minutes. Earth as seen from the Moon This view of the Earth rising over the Moon's horizon was taken from the Apollo 11 spacecraft. The lunar terrain pictured is in the area of Smyth's Sea on the nearside.