| Abstract from DBPedia | The core of the Sun is considered to extend from the center to about 0.2 to 0.25 ofsolar radius (140,000 - 170,000 kilometres (86,000 - 110,000 miles)). It is the hottest part of the Sun and of the Solar System. It has a density of 150 g/cm3 at the center, and a temperature of 15 million kelvins (15 million degrees Celsius, 27 million degrees Fahrenheit). The core is made of hot, dense plasma (ions and electrons), at a pressure estimated at 265 billion bar (3.84 trillion psi or 26.5 petapascals (PPa)) at the center. Due to fusion, the composition of the solar plasma drops from 68–70% hydrogen by mass at the outer core, to 34% hydrogen at the core/Sun center. The core inside 20% of the solar radius contains 34% of the Sun's mass, but only 0.8% of the Sun's volume. Inside 24% of the solar radius is the core which generates 99% of the fusion power of the Sun. There are two distinct reactions in which four hydrogen nuclei may eventually result in one helium nucleus: the proton–proton chain reaction – which is responsible for most of the Sun's released energy – and the CNO cycle.太陽核（たいようかく、Solar core）は、太陽の中心から太陽半径のおよそ0.2倍から0.25倍の範囲に広がっていると考えられている。太陽核は太陽系において最も高温であり、中心部の温度は1500万 ケルビンに迫る。中心の圧力は2.4×1016Pa、中心から0.2太陽半径では4.3×1015Paである。中心部の密度は約15万 (kg/m3)に達する。太陽の核は、プラズマ状態にある高温で高密度のガスからできている。0.24太陽半径以内の核は太陽のエネルギーの99%を産み出している。 (Source: http://dbpedia.org/resource/Solar_core) |
