2.1 Spectral Classifications
Created by on 21 Feb 2016 @ 1:56pm
Stars can generally be classified by their color. A purple star is always Class O, a yellow star is always Class G. However, there can be vast differences within each class. Most Class M stars are tiny and don't emit much light... however, many K- and G-type stars can evolve into red giants. That makes them Class M, but they are NOTHING like the tiny stars that make up the vast majority of Class M stars. Since most stars spend most of their lives on the Main Sequence, the descriptions on this page can be applied to the majority of stars. The oddballs and outsiders don't necessarily fit the exact parameters here (and will be discussed elsewhere), but even the oddballs conform to the interstellar color scheme, so even a blue oddball is class B.
Spectral Class OColor: Dark blue/violet Surface Temp: 28,000° - 50,000° K Composition: Ionized atoms, helium Mass: 60 sols Radius: 15 sols Lumosity: 1,400,000 Magnitude: -3 Abundance: 0.00000003125% of all stars Lifetime: 10 million years Death: Supernova, becomes a black hole or neutron star. Examples: Mintaka, Kalidar, Zeta Puppis
Spectral Class BColor: Blue Surface Temp: 10,000° - 28,000° K Composition: Neutral helium, some hydrogen Mass: 18 sols Radius: 7 sols Lumosity: 20,000 Magnitude: -6 Abundance: 0.13% of all stars Lifetime: 100 million years Death: Supernova, becomes a neutron star> Examples: Rigel, Alpha Eridani
Spectral Class AColor: Light blue Surface Temp: 10,000° - 28,000° K Composition: Strong hydrogen and ionized metals Mass: 3.2 sols Radius: 2.5 sols Lumosity: 80 Magnitude: +1 Abundance: 0.6% of all stars Lifetime: 1 billion years Death: becomes white dwarf Examples: Vega, Sirius
Spectral Class FColor: White Surface Temp: 6,000° - 7,500° K Composition: Hydrogen, ionized metals, calcium, iron Mass: 1.7 sols Radius: 1.3 sols Lumosity: 6.0 Magnitude: +3 Abundance: 3% of all stars Lifetime: 3 billion years Death: Expands to a red giant, becomes planetary nebula and later, a white dwarf. Examples: Canopus, Procyon
Spectral Class GColor: Yellow Surface Temp: 5,000° - 6,000° K Composition: Ionized calcium, neutral and ionized metals Mass: 1.1 sols Radius: 1.1 sols Lumosity: 1.2 Magnitude: +5 Abundance: 7.6% of all stars Lifetime: 10 billion years Death: expands to a red giant, becomes planetary nebula and later, a white dwarf. Examples: Sol, Capella, Ka'Tula
Spectral Class KColor: Orange Surface Temp: 3,500° - 5,000° K Composition: Neutral metals Mass: 0.8 sols Radius: 0.7 sols Lumosity: 0.4 Magnitude: +10 Abundance: 12.1% of all stars Lifetime: 50 billion years Death: Expands to a red giant, becomes a white dwarf. Examples: Arcturus, Aldebaran, Alpha Centauri
Spectral Class MColor: Red Surface Temp: 2,500° - 3,500° K Composition: Ionized atoms, helium Mass: 0.2 sols Radius: 0.3 sols Lumosity: 0.04 Magnitude: +15 Abundance: 76.45% of all stars Lifetime: 1 trillion years or more becomes a white dwarf. Examples: Proxima Centauri, Wolf 359
Spectral Class LColor: Dark red Surface Temp: 1,300° - 2,500° K Composition: Metal hydride, neutral metals Mass: 0.1 sols Radius: 0.2 sols Lumosity: 0.02 Magnitude: +20 (possibly very abundant) Abundance: 1 trillion years or more Examples: Becomes a brown dwarf
Spectral Class TColor: Brown Surface Temp: less than 1,300° K Composition: Methane Mass: 0.08 sols Radius: 0.08 sols Lumosity: 0.001 Magnitude: +25 (possibly very abundant) Abundance: 1 trillion years or more
NOTICE: Classes L and T were created in 2006. You'd think that after 10 years, there'd be a bit more data about them, but most every source is woefully vague. I've done the best I can to put together profiles, but a lot of this is conjecture on my part. So like... don't take this stuff as fact.This information comes from the website of Star Trek the Final Frontier.
Categories: Information Databank