> Answer: Proxima Centauri b is 1.3 times the radius of Earth, or 1.2 times the radius of the Moon.
This seems to be a straight up bug. These two reference sizes are not the same.
Earth 6,371 km radius * 1.3 = 8,282.3 kilometers
Moon 1,737.4 km radius * 1.2 = 2,084.88 kilometers
Proxima B radius = 1.08 x Earth radius (estimate) [0] = 6,880.68 kilometers
[0] https://exoplanets.nasa.gov/exoplanet-catalog/7167/proxima-c...