equinox solstice summer ecliptic vernal autumnal earth celestial september equinoxes march sun sphere science path astronomy observing astronomical winter longitude
sun earth geometry solar solstice noon altitude degrees equinox north during june december figure horizon 6h
crater moon faustini temperatures reached pole upper seen south where cbc nasa coldest shadowy measured spot yet reconnaissance lunar orbiter
sun earth geometry solstice equinox june december during solar angles noon pole equator 6h latitude altitude 23 south relationship geography