Hora is an important aspect of Hindu astrology. A Rashi or Zodiac consists of 30 degrees. It is divided into two equal parts or halves called Horas. So each Hora measures 15 degrees.
Sun (Surya) and Moon (Chandra) are the owners of the Horas.
In all odd Rashis (Mesha, Mithuna, Simha, Tula, Dhanu and Kumbha) the first Hora is ruled by the sun and the second by the moon.
In all even Signs (Vrishabha, Karka, Kanya, Vrishicka, Makar and Meena) the first Hora is ruled by the moon and the second by the sun.