这取决于几个因素，包括（从地球附近经过的运动轨迹类似于彗星的太阳系第十二行星所携带的）红色尘埃用多少时间穿越地球大气层沉淀到它被第一次近距离观察并报告的地方。
This depends upon a number of factors, including how well the dust drops through the atmosphere to be deposited on land where the very first evidence will be closely watched for and thus observed.
这两个行星还会在七月初和十二月末相遇——除此之外的时间里出于各自的轨道。
These two planets will meet two more times - in early July and late December - before they will go their separate ways, not to meet again until 2022.
照片在距离土卫十二1200英里（约合1931公里）的地方拍摄，是迄今为止与这颗直径只有20英里（约合32公里）的小行星距离最近的一次拍摄。
Taken 1, 200 miles from Helene, this is the closest photo ever taken of the minute moon, which measures only 20 miles across.
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