The Nava-Grahas or Nine Planets

Sun or Surya is a royal planet and the king in astrology. He represents the soul, willpower, father, paternal relations, the king or the high officials. Its hot and angry, color is red, metal is gold and gem is ruby. Sun represents the eastern direction.
The sun stays in each rasi for one month and takes one year to complete the round of the zodiac. Its motion is quite fixed and a lot of Indian festivals are as per the suns entry into the various signs. For example, on January 14 it enters Makara and this day is celebrated as Makara Sankranti, On April 13th/14th it enters Mesha and this day is celebrated as Baisakhi. The change in seasons is also linked to the suns entry into various signs and nakshatras. He is the Pitrukaraka or planet connected with father.

Given below are the basic qualities and nature of the 9 planets. However, based on your Lagna and where these planets are placed they give different results.

Moon or Chandra is also a royal planet and is the queen in astrology. He represents the mind, emotions, sensitivity, the mother, house and domestic comforts, milk, sea and all things connected with the sea, hotel and food industry, textiles, and apparels. Its cold and calm, Its color is white, direction north-east, metal is silver and gem is a pearl. The moon is the fastest moving of the 9 planets and takes approximately 2-1/2 days to travel a sign. When the sun and moon are in the same rasi it is called Amavasya or new moon day or the 1st day of the dark fortnight. The lunar days or Tithi changes with every 12-degree difference between the sun and the moon. When the sun and the moon are in the exact opposite signs or 180 degrees apart, it is called Poornima or the full moon day or the 1st day of the bright fortnight. He is the Matrukaraka or planet connected with mother.

The sign in which your Moon is placed in the birth chart is called your Janma Rasi. The star constellation in which your Moon is placed is called your Janma Nakshatra. 

Mars or Mangala or Kuja is the commander in astrology. He represents energy, courage, younger brothers & sisters, armed forces, the police forces, commanders, administrators, men in high position, land, engineering, metals, real estate agents, and surgery. Its metal is copper and gem is coral, color is red and directly south.
Mars takes about 45 days to travel one sign. He is the Bhatrukaraka or planet connected with brother.

Mercury or Budha is the prince in astrology. He represents speech, intelligence, maternal uncles, short journeys, the medical profession, trade, computers and the web, astrology, and knowledge of the shastras, accounts, mathematics, journalism, printing, and publishing. Its metal is bronze, the gem is emerald, color is green and direction north.
Mercury takes about a month to travel a rasi. It is always within 27-degree distance from the sun from an astrological point of view.

Jupiter or Guru or Brihaspati is known as the “Devaguru” or the guru of the Gods. He represents higher knowledge, spirituality, priests, temples, teachers, research & scientists, lawyers & judges, children and knowledge of the sastras and astrology. Its color is yellow, metal gold, gem yellow sapphire, and direction northeast. Jupiter takes about one year to travel a sign. He is the Putrakaraka or planet connected with children.

Venus or Shukra is the “Daityaguru” or the guru of the demons. He represents spouse, sex life, kidneys and sex organ, dance, music, arts, gems and jewelers, wines, bars, gambling places, acting, fashion, cosmetics and beauty products. Its metal is silver, the gem is diamond, the direction is south-east and color is white.
Venus takes about a month to travel a sign and completes the round of the zodiac in 12 months. From an astrological point of view, it is always within 48 degrees of the sun. He is the Kalatrakaraka or planet connected with a spouse.

Saturn or Shani is the servant in astrology. He represents hard work, sorrow, old men, servants and the lower level workers, people in the iron and steel industry, municipality and drainage work. A well placed Saturn can bestow excellent power, prestige, name and fame and a badly placed Saturn can devastate you. Its metal is iron, color is blue, the gem is blue sapphire and direction is west.
Saturn is the slowest moving of the 9 planets and takes approximately 2-1/2 years to transit a sign and completes the round of the zodiac in 30 years. He is the Udyogakaraka or planet connected with the profession.

Rahu or Dragons Head or North Node represents, foreigners, foreign countries, foreign travel, engineering and the technical trades, smoke, old men, grandparents, theft, gambling, drinking, nonconformists, the underworld and the bad elements in the society. Its color is black, metal mixed-metal and gem is Gomedh.
Rahu takes approximately 1-1/2 years to travel a sign and hence completes the round of the zodiac in 18 years.

Ketu or Dragons Tail or South Node represents grandparents, technical trades, spiritual inclinations, superstitions, and electronics. Its color is brown and the gem is cat’s eye. Ketu is always in the opposite sign to Rahu, i.e., exactly 180 degrees away. Ketu also takes approximately 1-1/2 years to travel a sign and hence completes the round of the zodiac in 18 years.

Each of these 9 planets produces different results, and at times totally opposite results, while placed in the 12 different rasis. Again each has some good results and some bad results in each sign. This is an important aspect of astrology which must be remembered.
While placed at various specific distances from the sun, the planets Mars, Mercury, Jupiter, Venus, and Saturn become retrograde or appear to move in the backward direction. Sun and moon do not have any retrograde motion. The motion of Rahu and Ketu is always opposite to that of the other planets.

The seven main planets rule the seven days of the week.
Sun rules Sunday.
Moon rules Monday.
Mars rules Tuesday.
Mercury rules Wednesday.
Jupiter rules Thursday.
Venus rules Friday.
Saturn rules Saturday.
Rahu and Ketu do not rule any day