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exothermic fusion process comparison table

Subject	has location	has optimum density	has reactant	has part product	has minimum mass	has product	has duration	has definition	has optimum temperature	requires minimum mass at star birth	has next higher temperature reaction
carbon burning	center of star heavier than 4 solar masses	2 × 105 g cm-13	carbon	neon, magnesium			600 years	The stage when a star fuses carbon into heavier elements, making neon and magnesium. Carbon burning eventually occurs in all stars born with more than eight solar masses.	6 × 108 K	8 solar masses
helium burning		700 g/cm3	helium	carbon		carbon, oxygen	5 × 105 years	The stage when a star fuses helium into carbon and oxygen. All stars born with more than half a solar mass eventually burn helium.	2 × 108 K	0.5 solar masses	carbon burning
hydrogen burning			hydrogen		0.08 solar masses	helium		The fusion of hydrogen into helium and the process by which all main-sequence stars generate energy. Every star born with more than 0.08 solar masses burns hydrogen.			helium burning
neon burning	center of star heavier than 9 solar masses	4 × 106 g cm-3	neon	oxygen, magnesium			1 year	The stage in which a star burns neon into oxygen and magnesium.	1.2 × 109 K
oxygen burning		107 g cm-3	oxygen			silicon, sulfur	6 months	The stage when a star fuses oxygen into silicon and sulfur. It occurs only in stars born with over eight solar masses.	1.5 × 109 K	8 solar masses
silicon burning		3 × 107 g cm-3	silicon involved in many hundreds of nuclear reactions	iron 56			1 day	The end of the line for a high-mass star, silicon burning creates iron and other elements of similar mass and presages a supernova.	2.7 × 109 K

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