shadow

This is an excellent example of a contrail edge shadow in Italy. Edge shadows happen when a part of a contrail is lined up with the sun (from the point of view of the observer). This creates a slab of shadow through the haze, and the observer sees it edge on, so it looks like a dark beam...

Via Instagam and Twitter: Posted at about 2:41PM (PST), Jan 31st (today) (22:41 UTC) anthonyfloyd 38 minutes ago Weird feature in the #Vancouver Sky. Doesn't look like a contrail. Any ideas? #yvrwx And at 3:13PM. @AnthonyFloyd I was just trying to take pictures of it to what the heck hey?

Pictures taken Saturday morning about an hour before sunrise. The first picture looked like a blue horseshoe shape. While I was waiting on sunrise I kept watching it and it looked like the horseshoe shape turned white and "broke off" even though it was already "off". Is this a shadow it's...

A section of this video (starting at 4:27) is doing the rounds on Facebook. eg What we are seeing here appears to be a contrail that is almost perfectly aligned with the low sun (which is apparently close to the horizon, hidden behind the building). The aircraft is heading towards the...