It was a movie I saw when I was young in the 70’s.  Not sure how old it was…it was in color.  I can only remember the end, because it freaked me out a bit. Its a space crew of maybe 4 or 5 people and are on another planet ( not sure if its Mars or some made up place)  Anyways, the ed of the movie the whole soace craft they are in is being consumed by some large slimy creature…like they can see out thise little round space craft windows the insude of the creature eating them.