reply to post by Zaphod58
The thing to note is the trail necks down (gets slimmer), so you know the direction of travel. That is, the satellite takes a snap shot, and fat trail
means past travel.
The trail is 10 miles long. Figure 200mph for the plane. That's 3.33 miles per minute. So we are seeing 3 minutes of travel. Now the fat part of the
trail is about 3/4 of a mile wide. That puts the wind dispersing the contrail at 15mph. All of which is interesting but doesn't exactly lead to
If you want to view this on Google Earth, the trail starts at
and ends at
There is an additional dark streak at
but I can't say conclusively that it is another contrail.