Sirius A is the brightest star in the night sky and is part of the Sirius binary star system, located approximately 8.6 light-years from Earth. It is a main-sequence star of spectral type A1V, known for its blue-white hue and significant luminosity, being about 25 times more luminous than our Sun. Sirius A is often referred to as the 'Dog Star' due to its prominence in the constellation Canis Major, which translates to 'Greater Dog' in Latin. Its brightness and position have made it a key reference point for navigation and timekeeping throughout history, influencing various cultures and mythologies.