Clock A sits on the surface of a neutron star, clock B sits on Earth's surface, and clock C rests beside me in space, far from any masses. The clocks are synchronized and all read 12:00 P.M. Ignore the delay caused by light travel time in this question. When clock C reads 1:00 P.M.:

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The time dilation formula tells us that time moves slower in a stronger gravitational field. Clock A is on a neutron star, which is a very dense and massive object, and therefore experiences a strong gravitational field. Clock B is on Earth, which also has a gravitational field but much weaker than that of a neutron star. Clock C is in space, far from any masses and therefore experiences negligible gravitational effects. As a result, time moves slowest for clock A and fastest for clock C.

When clock C reads 1:00 P.M., it means that one hour has passed for clock C. However, since time moves slower for clock A than for clock C, less than one hour has passed for clock A. On the other hand, since time moves faster for clock B than for clock C, more than one hour has passed for clock B. Therefore, at 1:00 P.M. according to clock C, clocks A and B will show times between 12:00 P.M. and 1:00 P.M., with A earlier than B.

Clock a Sits on the Surface of a Neutron Star