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First time I noticed 'Arcturus' was decades ago.
I had dinner over some friends' house, and after the evening
was over, one buddy walked me out to my truck.
It was a warm, pleasant evening and we were in an involved
conversation.

So as we were standing out by the street talking, I noticed
the blinking light of a 'airplane' in the night sky.

But after twenty minutes of so, I noticed that the plane's
blinking light had barely moved!

I mentioned this to my friend - who was an avid amateur
astronomer - and he laughed -"That's not a plane, that's
Arcturus! - It's a star!".

Actually it's a binary star - TWO stars in a rapid, tight
orbit around each other - hence the 'Twinkling' that makes
it look like a blinking airplane light.
It does a fast red-blue shift back and forth as it rotates.

So if you want to find Arcturus - look in the northern sky
for a bright twinkling star that looks very 'airplane-like'.

Video:

Scintillation - Twinkling Star Arcturus