Astounding vol. 42, no. 6 (February 1949)
Yeah no idea what's going on here, it's all a little mad. What are those three disks? Are those space-text-messages supposed to be literal, as in, he can see them floating in space? Or less literal, like he can hear them or see them on a console but they're reproduced for us?
Original magazine: https://archive.org/details/Astounding_v42n06_1949-02_cape1736