One of my good friends is small and was young looking (she's in her 50s now; the young looking can't last forever :-) and an astronomer. She would go to judge science shows at high schools, etc. and the other judges would think she was a student!

Size and age, physical things, don't really matter so much overall because our looks (and outlooks) change with time. It doesn't really matter, if you are climbing a mountain, what you look like? You just climb your best and eventually you get there? Decide where you would like to go, what you would like to do or be like and work toward that. I'm 63 and still trying to get up my mountain. I look so much different from when I started, my husband does not recognize me in pictures of when I was your age.