What is the fine-grained topic of the following text: Lovell had quite the résumé: Best known as the commander of Apollo 13 — played by Tom Hanks in the 1995 Ron Howard movie — he is one of only 24 people to have flown to the moon, the first of only three to fly to the big rock twice and the only one to have flown there twice without making an actual landing. Only return the topic.
Jim Lovell's achievements in space exploration