I am looking for a book that I read in the 7th or 8th grade. It was from the Golden age of Sci-fi. It was written long before the Heechee Saga, but had a similar theme. It was maybe 200 pages long. It was about a group of people that got into a spaceship that had been abandoned along with many others. They went to a predetermined destination, that was already programmed in. When they got to where the course sent them, the sun went out momentarily and a flood washed a bunch of spaceships out of a mountain. When the light returned, they saw all of the ships. I can't remember the name of the book, or the author. I had thought it was called Jem, or Under a Sea of Stars, but I find nothing named that in any search. Can anyone help me?