2012 noctilucent cloud season begins
Tuesday, June 19, 2012 - 08:00
in Astronomy & Space
(Phys.org) -- Data from NASA's AIM spacecraft show that noctilucent clouds (NLCs) are like a great "geophysical light bulb". They turn on every year in late spring, reaching almost full intensity over a period of no more than 5 to 10 days--and the bulb is glowing. "They were visible to the north for about 3 hours as we flew between Ottawa and Newfoundland at 35,000 feet" said Brian Whittaker.