"Ordeal in Space" is a science fiction short story by American writer Robert A. Heinlein, originally published in Town & Country, May 1948.
It is one of Heinlein's Future History stories, and appears in his collection The Green Hills of Earth.
He is unable to hold on, despite supreme effort; he drifts away from the ship and has far too much time to ponder things.
After living in fear and sadness for a time, he must face his troubles while rescuing a kitten stuck on the 35th-floor ledge of a building.
Heinlein includes a variant verse to the hymn Eternal Father, Strong to Save, dedicated "to those who venture into space," in the story.