Whatever your point of view, the dark side of the Moon is the one facing away from the Sun. Yesterday, beginning at 13:31 UTC, the Moon moved between the Solar Dynamics Observatory and the Sun. The satellite had a view of a partial solar eclipse from space. These a lunar transit occur two or three times each year. Yesterday’s lasted two and a half hours, the longest thus far. When the next one will occur will be determined after planned adjustments in SDO‘s orbit.
Notice how crisp the horizon is on the Moon. The Moon has no atmosphere around it to refract the light from the Sun.
The movie shows the Sun seeming to wobble quite a bit. The fine guidance systems on the SDO instruments need to see the whole Sun in order keep the images centered, but the Moon blocks too much light during the transit. Once the transit is finished, the fine guidance systems come back online to provide steady images of the Sun.[youtube ww.youtube.com/watch?v=a8_w3POh0FA]
Video Credit: NASA