The Moon is Earth’s only natural satellite—a rocky, cratered body about one‑quarter the diameter of Earth, orbiting at an average distance of approximately 384,400 km. It influences tides, stabilizes Earth’s axial tilt, and was formed about 4.5 billion years ago following a collision between Earth and a Mars-sized object.
Source: science.nasa.gov
10/12/2021
During polar day, in Arctic and Antarctic summer, the Sun stays above the horizon for periods of 24 hours or more. Recorded on December 4, this fisheye timelapse image tracks the Sun in multiple frames as it completes a circle in the summer sky above Union Glacier, Antarctica. Of course on that date, Union Glacier's sky did grow dark even though the Sun was above the horizon. Captured during the brief period of totality, an eclipsed Sun is at bottom center of the composite view. Near the edge of the total eclipse path across planet Earth, the Moon's shadow darkens the sky above.