The H surface brightness-radius relation: a robust statistical distance indicator for planetary nebulae
The H surface brightness-radius relation: a robust statistical distance indicator for planetary nebulae
Measuring the distances to Galactic planetary nebulae (PNe) has been an intractable problem for many decades. We have now established a robust optical statistical distance indicator, the Hα surface brightness–radius or SHα–r relation, which addresses this problem. We developed this relation from a critically evaluated sample of primary calibrating PNe. …