Sky Art
 

It's been a pleasant couple of days for looking up here in Canberra.

Friday morning, saw four very straight long contrails, equally spaced heading south out over Bungendore way. Yesterday, saw two making a single orbit over Harden then heading north, with another seven long straight lines heading south again.

Then this morning, there looked to be the remains of three or four orbit contrails over Goulburn.

Each day the southern tracks were all equally spaced too, very tidy. How do they work that out?

My guess would be the flights were SYD - MEL, fairly evenly longitudinally spaced on the same route. The wind aloft moves each trail downwind making it look like parallel tracks?