Sun and Moon orbiting its own axis
“It is not for the sun to catch up with the moon, nor does the night surpass the day; and each one of them floats in its orbit.” (Qur’an, 36:40)
“It is He Who created The Night and the Day, And the sun and the moon: All (the celestial bodies) Swim along, each in its Rounded course.” (Qur’an 21:33)
Humans thought that the Sun was stationary and did not rotate about its own axis like the Earth does, but later discovered the Sun actually rotates on its own axis.
It is noticed that the sun has spots which complete a circular motion once every 25 days so the sun takes approximately 25 days to rotate around its own axis.
The Moon also rotates around its axis in the same duration that it takes to revolve around the Earth. It takes approximately 29.5 days to complete one rotation.