Heard a 'roar' like a really load truck engine around 6:30pm PDT USA last night.... we looked for a rig on the road going by our house, but nothing. It was dark out, but overcast so didn't see any lights, but really we didn't think to look "up". We are not on any flight paths around this time either. Hummmm, maybe?? Which would make it around northern Idaho to Canada...??