Between the night of November 11, 2019 and the early morning of the 12th, a rare transit of Mercury across the Sun was observed by the Solar Observatory "HINODE" (Solar-B) in entirety and the images and video footage it captured were shared with the world. Mercury, with a diameter measuring only 1/285 of that of the Sun, appeared as a tiny black dot.

Video footage of Mercury passing across the surface of the Sun shows that Mercury moves in a slightly wavy path rather than a straight line. SAKAO Taro, a member of the Solar-B Project Team, comments on this phenomenon as follows: "Such phenomenon occurs because HINODE observes the Sun while orbiting the Earth at approximately 680 km over the North and South Poles. As a result, the position of Mercury vis-à-vis the Sun appears to be different depending on the observer's location." SAKAO continues: "It's interesting that we are learning about the movement of HINODE from the perceived trajectory of Mercury."

The next time Mercury moves across the surface of the Sun will be during daytime in November 2032. We could not witness the event this time since it occurred at night in Japan, but we will be able to observe it next time.