Astronomy Picture of the Day——水星全貌
All of Mercury
Image Credit: NASA/JHU Applied PhysicsLab/Carnegie Inst. Washington
Explanation: Only six years ago, the entiresurface of planet Mercury was finally mapped. Detailed observations of theinnermost planet's surprising crust began when the robotic have been ongoingsince the robotic MESSENGER spacecraft first passed Mercury in 2008 andcontinued until its controlled crash landing in 2015. Previously, much of theMercury's surface was unknown as it is too far for Earth-bound telescopes tosee clearly, while the Mariner 10 flybys in the 1970s observed only about half.The featured video is a compilation of thousands of images of Mercury renderedin exaggerated colors to better contrast different surface features. Visible onthe rotating world are rays emanating from a northern impact that stretchacross much of the planet, while about half-way through the video the lightcolored Caloris Basin rotates into view, a northern ancient impact feature thatfilled with lava. Recent analysis of MESSENGER data indicates that Mercury hasa solid inner core.
水星全貌
六年前，科学家终于完成了水星整个表面的绘制工作。自2008年“信使号”飞船首次飞越水星以来，便开始了该飞船对太阳系最内侧行星地壳的详细观测工作，一直持续到2015年“信使号”降落水星表面为止。在此之前，水星表面的大部分结构对我们来说是未知的，因为它太过遥远，无法用地面望远镜进行观察，而“水手10号”在20世纪70年代飞掠水星时只观测到约一半的结构。这段精彩的视频由数千张以艳丽颜色渲染的水星照片合成而成，以更好地对比不同的水星地表特征。在这个旋转的世界中，可以看到从北部撞击坑发出的射线，它们延伸穿过行星的大部分区域，而在视频播放过半时，浅色的卡洛里斯盆地旋转进入视野，这是一个充满熔岩的北部古代撞击地貌。最近对“信使号”数据进行的分析结果表明水星有一个固态内核。
参考文献：
https://youtu.be/DmYK479EpQc
近期文章：
Astronomy Picture of the Day——横跨南冕座