The answer: Probably a meteor.The phenomenon was spotted over the Lake Tahoe area, the Sacramento Valley and the Bay Area around 5:45 p.m. local time.It has not been 100% identified, however "evidence is growing the object seen was a meteor," according to the National Weather Service Bay Area."A meteor can create a very high level cloud called a noctilucent cloud," the weather service said.Noctilucent clouds were previously observed over Monterey, California in 2011, the National Weather Service said via Twitter. They were formed by the launch of the NPOESS Preparatory Project spacecraft from Vandenberg Air Force Base near Santa Barbara.There was speculation that the cloud-like formations seen Wednesday were also related to a rocket launch at Vandenberg.However, United Launch Alliance, a launch service provider for national security missions, announced that the launch had been scrubbed due to "indications of booster complications."It was the fourth time United Launch Alliance scrubbed the much-anticipated launch of a Delta IV-Heavy rocket from Vandenberg to carry the NROL-71 satellite into orbit for the National Reconnaissance Office.The launch has been rescheduled for Thursday.
CNN's Alexrandra Meeks also contributed to this story.