Above Peter something sprayed! Bashny.Net

Above the south-west of Peter, in a few hours watching a picture. The plane makes a circle, leaving a trail vaguely reminiscent of an inversion, but since I'm on voennouchetnoy specialty 201/200 engineer forecaster, authoritatively declare, add-on is not. Cloud sprayed unknown *** rapidly migrate and loses altitude, by the way, absolutely not peculiar contrails. Most interestingly, this is the third semi-cloud first two did not attach much importance, and they were not as round. Unfortunately, expect that the spray dry cream for coffee, we do not have, but what exactly is sprayed, you decide. On otmosfernye phenomenon is not written off, since clearly seen a plane. And zagogulinka right of the clouds in the pictures, left when the plane went on to decline.