Mercury’s orbit and rotation produces a bizarre phenomenon. This time lapse shows Mercury orbiting the Sun. As it does so, it spins like you would expect, but look carefully and you’ll notice that every so often the spinning seems to stop before carrying on again.
From a ground perspective, it appears like this. What’s going on here? Well, sunrise to sunrise on Mercury, or a what is called a solar day, lasts longer than a Mercurian year.
In fact, there are two Mercurian years for every one solar day. Put simply, it rotates incredibly slowly. Mercury’s orbit is also pretty elliptical, and it travels faster at this point in its orbit compared to this part.
During this fastest point, Mercury’s angular orbital velocity increases so much it actually overcomes its rotational velocity, making the Sun appear to pause and even go backwards a bit in the sky before carrying on like normal. Amazing huh? Check the pinned comment for more!