Sources of Knowledge
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Human Brain Facts and Answers By Disabled World - 2008-10-19 Questions answers and facts relating to the human brain and the study of the brain organ including the spinal cord. What is the Brain? The brain is the center of the nervous system in animals.
Description 3D simulation of the Solar System and night sky in real time - the Sun, planets, dwarf planets, comets, stars and constellations. - Heliocentric view with real-time positions of planets and planetary orbits - Schematic and realistic sizes of the planets and distances between them - Movement of the planets in time to see how they move in relation to each other - Virtual Orrery - Planetary exploration with info texts and additional views such as structure - Dwarf planets (Pluto, Ceres, Haumea, Makemake. Eris) and their orbits - Comets (Siding Spring, Lovejoy 2013, Lovejoy 2011, Panstarrs, ISON, Halley) - positions and trajectories - Stars and constellation of the night sky as viewed from a given location - Changes in the night sky during night, month and year - Searching of the stars and constellation, ecliptic line, grid lines and more
PICTURE OF THE DAYsee all » This image shows part of the North America Nebula (NGC 7000) in the constellation Cygnus the Swan. The orange supergiant Xi Cygni (also known as 62 Cygni) is the central star, together with the “west coast” of NGC 7000. (2.4-inch Takahashi FS-60C refractor at f/6.2, Quantum Scientific Instruments QSI 540wsg CCD camera, Hydrogen-alpha/RGB image with exposures of 60, 10, 10, and 10 minutes, respectively)
Prehistory (meaning "before history", or "before knowledge acquired by investigation", from the Latin word for "before," præ, and historia) is the span of time before recorded history or the invention of writing systems. Prehistory refers to the period of human existence before the availability of those written records with which recorded history begins. More broadly, it can refer to all the time preceding human existence and the invention of writing. The notion of 'prehistory' began to surface during the Enlightenment in the work of antiquarians who used the word 'primitive' to describe societies that existed before written records. The first use of the word prehistory in English, however, occurred in the Foreign Quarterly Review in 1836. The occurrence of written materials (and so the beginning of local "historic times") varies generally to cultures classified within either the late Bronze Age or within the Iron Age.
An undead völva, a Scandinavian seeress, tells the spear-wielding god Odin of what has been and what will be in Odin and the Völva by Lorenz Frølich (1895) For the practices and social institutions of the Norse pagans, see Norse paganism Norse mythology, or Scandinavian mythology, is the body of mythology of the North Germanic people stemming from Norse paganism and continuing after the Christianization of Scandinavia and into the Scandinavian folklore of the modern period. The northernmost extension of Germanic mythology, Norse mythology consists of tales of various deities, beings, and heroes derived from numerous sources from both before and after the pagan period, including medieval manuscripts, archaeological representations, and folk tradition.