Contrails

Contrails = condensation trails, the painting of white lines in the sky by aircraft cruising at high altitude.
It's condesed water vapour, a product of the flames inside the jet engines where the hydrogen part of kerosene
is combined with oxygen and produces water. This water freezes at typical cruse altitudes of 29'000 ft to 41'000 ft.
I took my telescope to see the 'heads' of those trails. There are aircraft. It's difficult to capture them because they move so fast
- up to 500 mph. And you need a loooong lens to reach them at a distance of about 10 to 15 miles.

Pink after sunset	High altitude traffic	Air Canada B-767-300
British Airways A320	Light contrail at night	Lufthansa A330-300
Air Canada B-767	Air Berlin A320	British A321
Alitalia Cargo MD-11 coming from the north	Cruising Alitalia Cargo MD-11	Alitalia Cargo MD-11 just overhead