Saw the film "The Martian" (highly recommend btw!) and at the sol day chapter breaks there was that weird ping, which I thought had to have been lifted from the song Meddle by Pink Floyd. Upon further inquiry it turns out that folks are saying the sound is a sonar ping... however according to the dubious wiki: The ping sound heard at the beginning of the song was created as the result of an experiment at the very beginning of the Meddle sessions. It was produced through amplifying a grand piano, played by Richard Wright, and sending the signal through a Leslie rotating speaker.
I must say the sound in The Martian sounds to me as if it was sampled direct from Meddle, and is not an authentic sonar ping.
No mention of Pink Floyd in the credits.
The song is actually "Echoes." 
That is correct about how Rick Wright came up with that sound, he plucked a grand piano string with a guitar pick and sent it through a Leslie.
Duh of course Echoes. obviously that side made off with some critical brain cells.
Anyhow, seems like if the director sampled Echoes he ought to have given a nod to Pink Floyd.
