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Weather picture of the month August 2008 

 

 
Picture taken at Kampenhout on June 24 2008 at 0812 hours CET.

 

Belonging to the group of special clouds, a contrail usually forms when warm exhaust gases (containing water vapor) of the engines of an airplane cool off in the surrounding environment. When this surrounding air is almost saturated, this extra moisture condensates immediately, sometime leading to very long persisting trails. But what are the chances of getting a picture of a contrailing airplane in front of the Moon's disk? A couple of things are needed:
1. a contrail must form (for a hint see this link),
2. the Moon must be present, preferable the disk must be visible 50% or more,
3. you need some upper air traffic (for Belgium see this link),
4. when you like to have a recognizable airplane, the Moon should be visible during the daylight, preferable time is the summer period,
5. luck, even with all four previous elements present, the chances that a plane crosses the disk remains pretty low. So when you can obtain such a shot, you're thrilling moment of luck came along.

The picture, taken 2hrs 45minutes after sunrise, shows a Lufthansa Boeing 747-400 (D-ABVB) cruising at an altitude of well over 11 km enroute Newark-Frankfurt with flight number DLH403.



List of pictures of the month