复现的火星

2020年9月11日

The Reappearance of Mars
Image Credit & Copyright: David Duarte and Romualdo Caldas

Explanation: Mars reappears just beyond the Moon’s dark limb in this stack of sharp video frames captured on September 6. Of course to reappear it had to disappear in the first place. It did that over an hour earlier when the sunlit southern edge of the waning gibbous Moon passed in front of the Red Planet as seen from Maceio, Brazil. The lunar occultation came as the Moon was near apogee, about 400,000 kilometers away. Mars was almost 180 times more distant. It was the fourth lunar occultation of Mars visible from planet Earth in 2020. Visible from some southern latitudes, the fifth lunar occultation of Mars in 2020 will take place on October 3 when the Moon and Mars are both nearly opposite the Sun in planet Earth’s sky.

Tomorrow’s picture: 1,000 Meteors

复现的火星
影像提供与版权: David Duarte and Romualdo Caldas

说明: 在这幅由摄于9月6日的影片定格叠成之清晰影像里，火星刚从月亮黝黑的临边后方复现。既然提到复现，那它先前必然消失了。从巴西的马瑟欧市看出去，火星是在拍照的1小时之前，被蛾眉状的渐亏月掩过。这次的月掩星事件发生时，月亮位在离地球约400,000公里的远地点附近，而火星的距离大约是这个月距的180倍。这是2020年，在地球可见的5次月掩火星事件的第4例。将发生在10月3日第5次月掩火星，可见地点为南半球的部分区域，届时在地球的天空中，月亮和火星都在与太阳180度反向的”冲”附近。

明日的图片: 1,000 Meteors