time for Earth to make a complete rotation on its axis;
"two days later they left"
"they put on two performances every day"
"there are 30,000 passengers per day"
例句
用作名词 (n.)
A sidereal day is shorter than a mean solar day by 3 minutes and 56 seconds. 恒星日比平均太阳日短三分五十六秒。
Its low amplitude makes it less important as a source of disturbance in magnetic prospecting than the solar component. 作为磁法勘探中的干扰源,它的幅度很小,所以远不及太阳日变分量那么重要。