While I do not post photographs in my own area of Facebook (preferring to use my SmugMug site), numerous other people have elected to use my photos as their own profile images for Facebook.
The screen shots shown here are shown as seen from the Internet, from a browser not logged in to Facebook, so as to protect people's privacy. (In other words, anyone could see these, and I am not compromising anyone's privacy settings from their Facebook account.)
These photos come from a variety of places, including NASA/GSFC staff photos, HSO images, and private events.
Tom Stephens worked as a programmer at NASA, now living in Utah, and has used my staff photo both for Facebook as well as for his own personal web site.