UBVRI Landolt Standards

These data are a selection of stars supplied by Arlo Landolt to serve as bright standards of the UBVRI photometric system. They provide internally consistent homogeneous broadband standards for the Johnson-Kron-Cousins photometric system for telescopes of intermediate and large size in both hemispheres. The filter bands have the following effective wavelengths: U, 3600Å; B, 4400Å; V, 5500Å; R, 6400Å; I, 7900Å. The positions are taken from the Naval Observatory Merged Astronomical Database (NOMAD). Positions are converted to the epoch, equator, and equinox of the middle of the current year; radial velocities are included in the calculation where available.

The Astronomical Almanac Online! 2020