I can tell you from my experience with our members that we have quite many field professionals here, from those that actually landed hardware on Mars, to those working for large space launch providers and in space systems integration, analytics and space policy, space historians,... That isn't really a coincidence as we actively work in promoting our site to relevant expert communities (see e.g. this threadthis thread as an example of that), but unfortunately, I'm not at liberty to disclose which individuals that are or where they work, unless they're comfortable in sharing that by themselves (site policy). You might however recognize some of the names in our list of members by yourself, though Elon Musk that ain't.
replaced http://meta.space.stackexchange.com/ with https://space.meta.stackexchange.com/