Graha or planets are deities in Hindu belief, and Hindu astrology.

There are nine, called Navagraha (Nine planets)

1. Surya, the Sun
2. Chandra or Soma, the Moon
3. Mangala, the Mars
4. Budha, the Mercury
5. Brihaspati or Guru, the Jupiter
6. Shukra, the Venus
7. Shani, the Saturn
8. Rahu, shadow
9. Ketu, shadow

Astrology: These planets  play vital role in ones life and astrological predictions are done birth details like date,time,lcoation.

People offer prayers to reduce the impact to a planet which is malefic  in his zodiac.