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
West Yorkshire Hurdle West Yorkshire Hurdle The West Yorkshire Hurdle is a Grade 2 National Hunt hurdle race in Great Britain which is open to horses aged four years or older. It is run at Wetherby, West Yorkshire, over a distance of about 3 miles (3 miles and 26 yards, or 4,852 metres), and during its running there are twelve hurdles to be jumped. The race is scheduled to take place each year in late October or early November. The event was established in 1990, and it was initially contested over 3 miles. It was extended to about 3 miles and 1 furlong