Assertion: sun's center | /r/HasProperty | radius zero
Facets:
Source sentences:
text: Traveling inward, hydrogen mass fraction starts to decrease rapidly after the core radius has been reached (it is still about 70% at a radius 25% of the Sun's radius) and inside this, the hydrogen fraction drops rapidly as the core is traversed, until it reaches a low of about 33% hydrogen, at the Sun's center (radius zero).