Aurora- Light of Mystery Essay -- Papers

Aurora- Light of Mystery Text Box: This shuttle image shows the characteristic oval shape of the aurora.i What is aurora? Auroras, or polar lights, are the luminous phenomenon of the upper atmosphere occurs in high latitudes of both hemispheres. Auroras in the northern hemisphere are called aurora borealis and those in the south hemisphere are called aurora australis. Aurora (Latin for 'dawn') is beautiful and amazing lights which are visible in the dark sky in the poles. It can appear as many different forms, but usually it is a greenish quivering glow near the horizon. In 1621 the term 'aurora' was coined by the French astronomer. More and more observations were done and a concrete description was archived soon afterwards. Many theories were developed this phenomenon. Some suggested that it was the reflection of sunlight of artic light and some believed it was the firelight at the edge of the world; however both hypotheses are rejected because it was found that aurora was found 100-400km above the earth surface which is well beyond the atmosphere. Around the 17th century it has been discovered that it is caused by the interaction between energetic plasma particles from outside atmosphere with atoms of higher atmosphere. Till now, not all the questions about aurora have been answered, but with the escalating astronautic technology, we have a much better understanding on this puzzling phenomenon. How does aurora form? At every moment the sun is giving out charged particles in solar wind. Some of these particles are captured by the earth magnetic field and the bombardment of the solar wind with the atmospheric particles... ...aurora_e/index.html The Exploration of the Earth's Magnetosphere. http://www-istp.gsfc.nasa.gov/Education/wmap.html Learning about Aurora. http://sprg.ssl.berkeley.edu/~cyclopi/lesson1.html Applied physics laboratory site. http://www.jhuapl.edu/newscenter/pressreleases/1998/auroras.htm NASA website. http://www-istp.gsfc.nasa.gov/ Web Exhibits site. http://webexhibits.org/ Britannica Online. http://www.britannica.com/ Hyperphysics. http://hyperphysics.phy-astr.gsu.edu/hbase/hph.html Evaluation on resource: My source information comes from books, journals and internet. The information about most topics is quite consistent except the formation of voltage drop in the aurora acceleration region. There are many theories explaining the phenomenon, but I only concentrated on the two main ones.