ver em fullscreen [F11]


video credit & copyright: Jean-Luc Dauvergne (Ciel et Espace);



it's northern noctilucent cloud season -- perhaps a time to celebrate !

composed of small ice crystals forming only during specific conditions in the upper atmosphere, noctilucent clouds may become visible at sunset during late summer when illuminated by sunlight from below

noctilucent clouds are the highest clouds known and now established to be polar mesospheric clouds observed from the ground

although observed with NASA's AIM satellite since 2007, much about noctilucent clouds remains unknown and so a topic of active research

the featured time-lapse video shows expansive and rippled noctilucent clouds wafting over Paris, France, during a post-sunset fireworks celebration on Bastille Day in 2009 july

this year, several locations are already reporting especially vivid displays of noctilucent clouds




































in apod.nasa.gov/apod