Are we alone?

One of our lunchtime guests, Peter, is a keen astronomer.  Knowing this I asked if he had any images of stars.
He whipped his phone out of his pocket and showed us the famous Horsehead Nebula, which he had taken from his observatory, built in their back garden in Pittenweem.
(Yes the neighbours were a bit alarmed when they saw it going up).
 
He says these stars are approximately 1,400 light years away or, put another way, the light from them has taken around 1,400 years to reach us. 
 
Are we alone in the universe?
Peter, who did physics tripos at Cambridge, reckons it’s a “racing certainty” we are not.

 
PS Special thanks to Peter for todays blip photo.