Property:Spectral class

This is a property of type Text, and is set and generated by the "Spectral class" field of {{InfoBoxSystem}}.. This property takes the first Character to represent a system's spectral type and it's second as it's luminosity class. As a limitation the luminosity classes of 1a, 1ab, and 1b are taken as being just 1

Spectral classification

In general, BattleTech sources use the Morgan–Keenan system to characterize individual stars.

All stars are classified by their spectral type and luminosity class. The spectral type indicates the color and temperature of the star. The seven major spectral types comprise 99 percent of all known stars. (Spectral subgroups are normally denoted by Arabic numerals, however numbers are more commonly used in fiction.)

Spectral Types

Class	Effective temperature	Vega-relative chromaticity	Chromaticity (D65)	Main-sequence mass (solar masses)	Main-sequence radius (solar radii)	Main-sequence luminosity (bolometric)	Hydrogen lines	Fraction of all main-sequence stars
O	≥ 30,000 K	blue	blue	≥ 16 M☉	≥ 6.6 R☉	≥ 30,000 L☉	Weak	0.000030%
B	10,000–30,000 K	bluish white	deep bluish white	2.1–16 M☉	1.8–6.6 R☉	25–30,000 L☉	Medium	0.12%
A	7,500–10,000 K	white	bluish white	1.4–2.1 M☉	1.4–1.8 R☉	5–25 L☉	Strong	0.61%
F	6,000–7,500 K	yellowish white	white	1.04–1.4 M☉	1.15–1.4 R☉	1.5–5 L☉	Medium	3.0%
G	5,200–6,000 K	yellow	yellowish white	0.8–1.04 M☉	0.96–1.15 R☉	0.6–1.5 L☉	Weak	7.6%
K	3,700–5,200 K	light orange	pale yellowish orange	0.45–0.8 M☉	0.7–0.96 R☉	0.08–0.6 L☉	Very weak	12%
M	2,400–3,700 K	orangish red	light orangish red	0.08–0.45 M☉	≤ 0.7 R☉	≤ 0.08 L☉	Very weak	76%

Luminosity Classes

Yerkes luminosity classes

Luminosity class	Description
0 or Ia+ or 1a+	hypergiants or extremely luminous supergiants
Ia or 1a	luminous supergiants
Iab or 1ab	intermediate-size luminous supergiants
Ib or 1b	less luminous supergiants
II or 2	bright giants
III or 3	normal giants
IV or 4	subgiants
V or 5	main-sequence stars (dwarfs)
sd (prefix) or VI or 6	subdwarfs
D (prefix) or VII or 7	white dwarf