A Classic!
One of the earliest of space adventure films, filmed in glorious black and white, this is George Pal's masterpiece - attempting to present a "realistic" view of space flight with a rocket right out of the Saturday matinees, a crew that predates the crew of the USS Enterprise, and dialogue that is somewhat contrived and dated. Filmed at the time with as much scientific input as could be arranged, and a serious attempt to play it straight, with very little comic(?) relief, make it a curiosity worth watching. See if you can spot the similarities between it and the later efforts that follow in the genre - there are many movies that owe this one a big debt of gratitude. It still plays well after all the years.