Two Complete Science-Adventure Books vol. 1, no. 10 (December 1953)
The poor woman in the top-left portion of the cover is about to meet a terrible fate, right? She's going to be read Vogon poetry from that book.
Lower right … "ballroom" of the skies? Those ships are *performing* for the giant creature, not just escaping from it?
Original magazine: https://archive.org/details/two-complete-science-adventure-books-v-01-n-10-1953-winter