Paul Oswald Ahnert (November 22, 1897 - February 27, 1989) was a German astronomer. He worked at the Sonneberg Observatory. He made an annual astronomical calendar called the "Kalender für Sternfreunde", which translates as the calendar for star friends. He included items in space which could easily be seen by amateur astronomers using small telescopes, or even just by eyesight. The calendar was first published in 1948 and was one of the few books from the German Democratic Republic which was highly regarded by people in other countries. After Ahnert's death the calendar continued to be published by astrophysicist Rainer Luthardt. An asteroid, 3181 Ahnert, was named after him.