Tycho Brahe (Martian crater) Tycho Brahe (Martian crater) Tycho Brahe is a nearly ovular crater on Mars named after the Danish astronomer Tycho Brahe (1546–1601). It is located in the Cerberus hemisphere around 49.8° south and 213.9° west, in an area which is south of the Martz crater and east of the Hellas Basin. It measures approximately 105 kilometers in diameter from east to west. The name was adopted by IAU's Working Group for Planetary System Nomenclature in 1973. The crater is crossed by Eridania Scopulus, an escarpment. Other nearby named craters are Huggins to the east, far south is Vinogradsky and northwest is
Stellar isochrone The resulting curve is an isochrone, which can be compared against the observational color-magnitude diagram to determine how well they match. If they match well, the assumed age of the isochrone is close to the actual age of the cluster. Stellar isochrone In stellar evolution, an isochrone is a curve on the Hertzsprung-Russell diagram, representing a population of stars of the same age. The Hertzsprung-Russell diagram plots a star’s luminosity against its temperature, or equivalently, its color. Stars change their positions on the HR diagram throughout their life. Newborn stars of low or intermediate mass are born cold but extremely