Ok, this one has been bugging me for a long time...

I'm not sure if it is a novel or novella or short story...

It has the "feel" of Heinlein but I don't think it is...

Definitely an old story....maybe from the fifties or sixties....  main
character is transitional HighSchool/College age :)

The only part I recall is the ending....  They're on Mars... the guy,
interested in archeological digs(?) finds an old ship. The ship is described
as Box-like... the ancient Martians had all "moved on" thousands of years
earlier...  Rumors of them all jaunting off into the cosmos as Marauders(?)
or pirates of some kind... but destined to return to their home in the
distant future... the guy takes off in the ancient box-like ship and, once
out in space, finds himself being pursued by the ancient Martians... they
appear as a V of ships on his "screens"... following him as he tries to
evade.... his ship is too old to out run them and they overtake him... he
then finds they are the ancient Martians, come home for a visit :)  And,
surprise surprise, they're human...(maybe?) some Martians had gone to Earth,
most went out into the cosmos for adventure...

So? Can anyone tell me who wrote this story? What's the title?

... and if you say it's Heinlein, I'll be very embarrassed :)

I'd like to read it again... haven't read it in at least 30 or 40 years :)

John T
PS:  I've already asked on the SciFi_Discussion group... usually they come
through for me but not this time.. sure hope you can help :)