axis - an imaginary line an object turns around , rotation - a complete spin on an axis , Revolution - one complete trip of one object around another object, equinox - the day when the Earth's rotation axis is leaning along Earth's orbit, neither toward or away from the sun. One this day we have equal amounts of day and night , solstice - the day when Earth's rotation axis is the most toward or away from the sun, gravity - a force which tries to pull two objects toward each other , mass - the measurement of the amount of matter in an object, weight - the measurement of the amount of effect of gravity on a given mass. , eclipse - when Earth or the moon casts a shadow on the other , tide - the rise and fall of the sea level caused by the gravitational pull of the moon and sun, tidal range - the difference between high and low tide ,

Space

打印
嵌入

排行榜

视觉风格

选项

切换模板

恢复自动保存：？