I kinda hope this answer is wrong for reasons that will become apparent, but perhaps on his head is
a space helmet
because
Tesla, Edison, Boss, Langley and Einstein are all the names of craters on the moon.
The reason I don't feel terribly satisfied with this answer is that
they're quite a long way apart -- certainly far enough that if you were making the journey you'd do it in some sort of vehicle -- and I wouldn't have thought that going from Tesla (38N,125E) to Boss (46N,89E) you'd pass at all close to either Langley (51N,86W) or Einstein (17N,89W), nor is Tesla (38N,125E) very close to Edison (25N,99E). And I don't think you'd say "the Tesla" or "the Boss" to refer to these craters. So it may just be coincidence that all these things are crater names.