Looking out over Lake Superior [ http://www.cciw.ca/…] at dusk you see Venus [ http://antwrp.gsfc.…] (lower left) and ... curtains? Like an ant [ http://www.orkin.co…] looking up at window curtains [ http://homeandfamil…], aurora [ http://dac3.pfrr.al…] frequently appear as huge flowing light displays. These colorful, often spectacular phenomena [ http://beatles.imv.…] are most frequently visible from locations near the Earth's poles. Aurora [ http://dac3.pfrr.al…] are caused by electrons [ http://pdg.lbl.gov/…] from the solar wind funneling to Earth along magnetic field lines [ http://www-spof.gsf…], and striking atoms and molecules in our atmosphere. Auroral [ http://www.geo.mtu.…] color is determined by which atmospheric ions are struck and recombine to form neutral atoms. Hourly updates of auroral sightings [ http://www.geo.mtu.…] are posted to the WWW. It is still controversial whether aurora make any sound audible from the ground. If you think you have "heard an aurora," please report it [ http://www.tp.umu.s…]!
