Charon is the largest moon while Pluto is small and is furthest from the sun, therefore, they would eclipse one another like on daily basis.
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May 27th, 2015
Charon and Pluto revolve about each other every 6.387 days. The two objects are both gravitationally locked
to the other, so each keeps the same face towards the other, that is why Pluto moon stays at the same place in the Pluto's sky. This is a
case of mutual tidal locking, compared to for instance Earth and the