According to Dr. Hugh Hill in an ISU lecture on astrobiology today—

• Astrobiology is the study of the origin, dispersion, and future of life in the universe.
• Bioastronomy is a combination of of biology and astronomy, searching for evidence of life in the universe.

This is certainly an interesting distinction—to me, at least. I had previously ascribed astrobiology to the folks at SETI which, though fascinating, never particularly interested me. Apparently, that's bioastronomy, which I could do without—let someone else worry about they why's and what's of that, someone with a sharper interest. Astrobiology? Where we came from and where we're going? That's more interesting, more useful, I think.

So I'll pass along a link I saw on NASA Watch: astrobiology.net