I'm 31 and whenever I hear any news about a celebrity with the last name 'Armstrong' I never know if they're talking about a cyclist, an astronaut, or a musician, so I just make it up on my mind.
Why wouldn't you pay attention to their first name?
How does it make a difference?
If you take notice of the people's first names, you might be better able to discern who they are talking about. There are not that many celebrities that share the last name Armstrong, so it should not be hard to learn.
I just realized where my problem comes from. Many years ago, my mother's friend married a man and changed her last name to 'Armstrong'.
Think of learning first names of people named Armstrong in terms of your mother's friend.  She wouldn't want to be confused with someone else, and celebrities would probably appreciate the same consideration.