Hi.

I don't know much about this, so someone else may want to say more.
I am not sure what you mean by an institution that is not faculty, but I know that distance learning programs are getting to be a bigger and bigger deal.

The University of Central Lancashire offers a Bachelors of Science degree in astronomy. Here is their web site.
http://www.star.uclan.ac.uk/

There are probably other institutions that offer these too - I only know about this one because I know solar astronomers there. They offer a distance learning class in solar physics.

Full fledged scientists generally have advanced degrees, often PhDs. I don't off hand know any way to get one of those in a distance learning program (although as I said, I don't know too much about this). If you are serious about a career in science, especially astronomy, my guess is that you would have to move to live near a university or research facility at some point.

hope that helps,
Terry