The constellation of Orion is rich with impressive nebulas. Of the many interesting details that particularly draws the eye is Barnard’s Loop, the bright red circular filament arcing down from the middle. The bright orange star on the upper left is Betelgeuse, while the bright blue star on the lower right is Rigel. Other famous nebulas visible include the Witch Head Nebula, the Flame Nebula, and the comparatively small Horsehead Nebula. NASA-APOD, Stanislav Volskiy.
The Sun or Sol, is the star at the centre of our solar system and is responsible for the Earth’s climate and weather. The Sun is an almost perfect sphere with a difference of just 10km in diameter between the poles and the equator. The average radius of the Sun is 695,508 km (109.2 x that of the Earth) of which 20–25% is the core. Image Credit: SOHO/EIT