Stellar Classifications

Stars are classified into groups based on their apparent color.  The color tells us informaiton about the surface temperature of the star.

The standard classes are (temperatures are in Kelvin):

  • O – Blue Stars: > 30,000 K
  • B – Blue-White Stars: 10,000 – 30,000 K
  • A – White Stars: 7,500 – 10,000 K
  • F – Yellow-White Stars: 6,000 – 7,500 K
  • G – Yellow Stars: 5,200-6,000 K
  • K – Orange Stars: 3,700 – 5,200 K
  • M – Red Stars: 2,400 – 3,700 K

Additional Classes:

  • L – Sub-Red Dwarf Stars:  1,300 – 2,400 K
  • T – Brown Dwarf Stars: 700 – 1,300 K
  • Y – Sub-Brown Dwarf Stars: < 700 K

The Sun is a G2V star.  The class is G – a Yellow Dwarf Star.  2 is its Subclass (they range from 0 to 9 with 0 being the hottest.  The V i the sun’s Spectral Type and it tells us that the sun in on the Main Sequence.

 

Scroll to top TEST Astronomical League