http://www.fi.edu/learn/braindrops.php Expand your knowledge of the world around you with a daily Braindrop from The Franklin Institute! en-us 2008 The Franklin Institute's Resources for Science Learning Fri, 09 May 2008 18:01:08 EST zwilliams@fi.edu 360 http://www.fi.edu/learn/images/rss_id.jpg http://www.fi.edu/learn/braindrops.php The corona is the very hot outermost layer of a star's atmosphere. Our Sun's corona can only be seen during a total solar eclipse. Fri, 09 May 2008 18:01:08 EST http://www.fi.edu/learn/braindrops.php