Absolute magnitude from an absolute magnitude in a specific filter band to absolute bolometric magnitude, a bolometric correction is applied. For Solar System bodies that shine in reflected light, a different definition of absolute magnitude (H) is used, based on a standard reference distance of one astronomical unit. In stellar and galactic astronomy, the standard distance is 10 parsecs (about 32.616 light-years, 308.57 petameters or 308.57 trillion kilometres). A star at 10 parsecs has a parallax of 0.1″ (100 milliarcseconds). Galaxies (and other extended objects) are much larger than 10 parsecs, their light is radiated over an extended patch of sky, and
British Champions Long Distance Cup British Champions Long Distance Cup The British Champions Long Distance Cup is a Group 2 flat horse race in Great Britain open to thoroughbreds aged three years or older. It is run at Ascot over a distance of 1 mile 7 furlongs and 209 yards (3,209 metres), and it is scheduled to take place as part of British Champions Day each year in October. The event was originally held at Newmarket under the title Jockey Club Cup. It was established in 1873, and was initially contested over 2¼ miles. The distance of the race was shortened to 1½ miles in