It is wonders of the universe such as these which got me hooked on physics many years ago, particularly astronomical events that we can observe relatively simply (a telescope with a solar filter will do). 

Although I studied the smallest known constituents of matter (quarks and gluons) when I was a proper physicist (before training as a patent attorney), it is knowledge of this small scale which helps us explain how the universe appears to us on a large scale.

So sit back in wonder to watch the transit of Mercury, observing two celestial bodies millions of miles away lining up in this way.