Iron birds

Last Saturday we got a nice walk outside. The sky was super clear and crystal-blue.
Time to time ( roughly every 5 or 10 minutes) there was a jet up in the skies, leaving snow-white trails behind.

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While there are a lots of funny theories on these "chem-trails", people more close to techno and physic world know what them are, and why they are appearing. Many detailed explanations can be found on Internet

After we came back from walking, I decided to see what exactly these "birds" are, where they go, and how high or/and fast they are. There is an excellent site for this, called FLIGHTRADAR24, where you can watch things in a real time.

So my next step was - to see if I can match the data on my PC screen to what I see above my head. Surprisingly, they do match surprisingly well.
Here are some of photos I made from my PC and from the skies.

Flight STOCKHOLM-KIEV

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Yes, this is exactly the same airplane in all four photos.

To tell the truth, it was quite a fun to chase these "birds" in the sky :)