The Role of Parallax in Exoplanet Research

Parallax is most powerful for close by things, but we have this distance ladders. We can't do exoplanet research on the other side of the galaxy because we can't like see through the center of the galaxy to that other side as well. So you can use cephids to understand how far away things are on the otherside of the galaxy. Those are pretty rare, but the galaxy is huge. I think more than 3,300 last time I checked.