The sources of information that might be used are ; (i)The spinning of the earth on its axis and (ii) the spinning of other planets on their axis
The relative motion of the earth is the spinning/rotation of the earth on its axis from west to east every 24 hours. every planets in the universe spins in the same direction of the earth ( i.e. from west to east ) except Venus and Uranus whose spins are retrograde.
To determine the relative motion we can observe the movements of other planets that way we can determine the relative motion of Earth in the universe.
Hence we can conclude that the sources of information are The spinning of the earth on its axis and the spinning of other planets on their axis.
Explanation:
