Our solar system was born when, in a spiral arm of the Milky Way, a giant rotating cloud of dust and gas began to collapse. Gravity compressed the dust and gases, and the cloud grew hotter and began to rotate faster. Over the next hundred million years, the gases were compressed until the center became so hot that nuclear fusion occurred, releasing enormous energy, combining charged hydrogen atoms to form helium. This process gave birth to a star, our Sun (Our Solar System, n.d.). Scientists have a large amount of data documenting the history of the solar system over the last 3.9 billion years, but it actually formed about 4.6 million years ago. The first 700 million years are a bit of a mystery because earthquakes, volcanic eruptions and erosion have erased evidence of that period. During those first 700 million years, the planets coalesced and water and other elements necessary for life were delivered to the inner planets (Cowen, 2009). Our solar system is a diverse and extremely interesting speck in the universe. Earth's solar system is located in the Milky Way and is part of a system of eight planets that orbit the Sun, the star that is at the center of our solar system. The Sun constantly burns gas, which heats and lights the Earth and other planets (Solar System Information, n.d.). The planets in our solar system vary widely in size, composition, distance from the Sun, and atmosphere. Of the 100 to 200 billion stars in the Milky Way, only about 6,000 can be seen with the naked eye from Earth, and one of these is the Sun. “Planets” means “wanderers” and were called so because they appeared to travel across the sky. Other objects in the solar system...... center of map...... Atmospheric Administration website: http://www.ncdc.noaa.gov/oa/climate/gases.htmlThe Greenhouse Effect . (n.d.). Retrieved December 14, 2011, from the University Corporation for Atmospheric Research website: http://www.ucar.edu/learn/1_3_1.htmGedzelman, S. (2002). Colors of the sky. Weatherwise, 55(1), 20. Retrieved December 6, 2011, from EbscoHost.Blue sky. (n.d.). Retrieved December 5, 2011, from the University of Wisconsin website: http://cimss.ssec.wisc.edu/wxwise/bluesky.htmlAstronomical Theory of Climate Change. (n.d.). Retrieved December 9, 2011, from the National Oceanic and Atmospheric Administration website: http://www.ncdc.noaa.gov/paleo/milankovitch.htmlSeasons of the Year. (n.d.). Retrieved December 9, 2011, from the National Aeronautics and Space Administration website: http://www-istp.gsfc.nasa.gov/stargaze/Sseasons.htm