Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

What does it mean the number after the stellar class? Magnitude?

  1. Jun 3, 2008 #1
    What does it mean the number after the stellar class? Magnitude?
     
  2. jcsd
  3. Jun 3, 2008 #2

    Borek

    User Avatar

    Staff: Mentor

    Like in G2 for Sun? Subclass. The lower the digit, the colder the star.
     
  4. Jun 3, 2008 #3

    Janus

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    If instead, you mean the roman numeral sometimes placed after the spectral class, this is the luminosity class as follows:

    0 Hyper giant
    I Super giant
    II Bright giant
    III Normal giant
    IV Sub giant
    V Main sequence (dwarf)
    VI Sub dwarf
    VII White dwarf

    Thus the Sun is a G2 V star.

    Sub classes of the luminosity class are labled a,ab & b
     
  5. Jun 3, 2008 #4
    Great.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: What does it mean the number after the stellar class? Magnitude?
Loading...