Bismillahir Rahman nir Raheem,
In olden times it was noted that each moving planet had a relationship with a fixed zodiacal sign. These relationships were orderly and clear-cut in the sense that the Sun and Moon ruled one sign each whereas the five known planets ruled two signs each.
Leo is ruled by Sun
Cancer is ruled by Moon
Aries & Scorpio are ruled by Mars
Taurus & Libra are ruled by Venus
Virgo & Gemini are ruled by Mercury
Sagittarius & Pisces are ruled by Jupiter
Capricorn and Aquarius are ruled by Saturn.
Here is a chart to make the relation clear.
Keep Me In Your Prayers