White lines in the sky

Most of you would have seen the trail of a high speed plane in the sky. It looks like a line of clouds and I don't know about others but as a kid, I was convinced that these were rockets being launched into outer space.

Today I saw one such plane and the same white line. I thought out loud that it's not very often that we get to see this white line now, and was wondering why has the frequency reduced. My friend gave me the answer that hit me hard, mostly coz it may be true: It's not that the planes have reduced, we have stopped looking into the sky as often as we used to.