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Solar system, assemblage consisting of the Sun and those bodies orbiting it: 8 planets with about 210 known planetary satellites; countless asteroids, some with their own satellites; comets and other icy bodies; and vast reaches of highly tenuous gas and dust known as the interplanetary medium. ....
Wendy Stenzel Kepler mission/NASA Detecting the transit of an extrasolar planet is very challenging. For example, the diameter of Earth is only 1/109 that of the Sun, so that, for an outside observer of the solar system, the passage of Earth would dim the output of the Sun by only 0.008 percent. In addition, a planet’s orbital plane must be aligned to pass in front of the star. Continuous observation without atmospheric distortion or day-night cycles not possible from Earth is essential to the mission. Kepler was placed in a heliocentric orbit with a 372.5-day period so that it gradually trailed Earth, thus avoiding effects from the magnetosphere that might interfere with the mission. ....
Çatalhüyük, major Neolithic site in the Middle East, located near Konya in south-central Turkey. Excavations (1961–65) by the British archaeologist James Mellaart have shown that Anatolia in Neolithic times was the centre of an advanced culture. The earliest building period at Çatalhüyük is ....
A central ceremonial plaza provided the nucleus of a Mississippian town, and each settlement had one or more pyramidal or oval earth mounds, surmounted by a temple or chief’s residence, grouped around the plaza. This settlement pattern was typical of most of Middle America (central and southern Mexico and Guatemala) since as early as 850 bce, but it had not diffused into North America until the advent of the Mississippian culture. The scale of public works in the Mississippian culture can be estimated from the largest of the earthworks, Monks Mound, in the Cahokia Mounds near Collinsville, Illinois, which is approximately 1,000 feet (300 metres) long, 700 feet (200 metres) wide, and 100 feet (30 metres) high. The magnitude of such public works and the distribution of temples suggest a dominant religious cult and a cadre of priest-rulers who could command the services of a large, stable, and docile population, as well as several artist-craftsman guilds. ....