PNe in the Coma I region

Using the planetary nebula luminosity function (PNLF), we derived distances to NGC 4494 (12.8+/-0.9Mpc), NGC 4564 (10.5^+0.8^_-1.0_Mpc), and NGC 4278 (10.2^+0.7^_-1.0_Mpc). The larger distance for NGC 4494 is significant beyond the 99% confidence level when the common systematic errors in all three distances are removed.

This agrees with the results of the globular cluster luminosity function and surface brightness fluctuation methods, both of which place NGC 4565 in front of NGC 4494. The large separation is also consistent with the results of Virgocentric flow models, which predict triple-valued solutions to the Hubble flow in that direction.