Page 25 - Ultimate Visual Dictionary (DK)
P. 25
STARS
HERTZSPRUNG-RUSSELL DIAGRAM
Hotter stars TEMPERATURE (°F) Cooler stars
65,000 18,000 9,000 6,500 4,500
More luminous stars -7
-6
-5
Deneb (blue supergiant) -4 S U PERG IA NT S Betelgeuse (red supergiant)
-3
-2
-1 GIANTS
0 Arcturus (red giant)
Sirius A (massive
main sequence star) +1
+2
+3 M A I N S E Q U E N C E S TA R S
+4
ABSOLUTE +5 The Sun (yellow main
VISUAL sequence dwarf)
+6
MAGNITUDE
+7
+8
+9
+10
Sirius B (white dwarf) +11
+12
+13 W R IT E DWA RF S Barnard’s Star (main
+14 sequence red dwarf)
+15
Less luminous stars +16
O5 B0 A0 F0 G0 K0 M0 M5
SPECTRAL TYPE
STELLAR SPECTRAL ABSORPTION LINES
Hydrogen Hydrogen Sodium Hydrogen
Calcium line gamma line beta line Helium line lines alpha line
STAR OF SPECTRAL
TYPE A (e.g., SIRIUS)
STAR OF SPECTRAL
TYPE G (e.g., THE SUN)
Hydrogen Magnesium Sodium Hydrogen
beta line lines lines alpha line
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