Table 13-1: EVOLUTIONARY STAGES OF A 25 M⊙ STAR
StageCentral temperature (K)Central density (kg/m3)Duration of stage
Hydrogen fusion      4 × 107      5 × 103      7 × 106 years
Helium fusion      2 × 108      7 × 105      5 × 105 years
Carbon fusion      6 × 108      2 × 108      600 years
Neon fusion      1.2 × 109      4 × 109      1 year
Oxygen fusion      1.5 × 109      1 × 1010      6 months
Silicon fusion      2.7 × 109      3 × 1010      1 day
Core collapse      5.4 × 109      3 × 1012      0.2 second
Core bounce      2.3 × 1010      4 × 1017      milliseconds
Supernova explosion      about 109      varies      hours