It is reddest when it is dimmest, which occurs every 14.5 months. "Motyxia sequoiae" glows the brightest and "Motyxia pior" the dimmest. The operator could easily determine the direction of travel, from the dimmest to brightest blip. This makes it one of the dimmest known galaxies. Globe at Night observations identify the dimmest stars that are visible given the surrounding conditions. Rings 6, 5 and 4 are the innermost and dimmest of Uranus's narrow rings. They are two of the dimmest known objects within 15 light years of the Sun. At their dimmest, their spectral types change to K or M. Sigma Octantis is the dimmest star to be represented on a national flag.