Lets learn the nature of the planets

Sun

Nature: It is square shaped, short height, dark red color, man, warrior (Kshatriya) caste, vice planet, Satwa guna, fire element and Pitta nature.
Signification: It controls king, father, copper, trees with fruits, small trees, wheat, bones, head, eyes, brain and heart.

Moon

Nature: It is spherical, woman, Vaisya (business-class) caste, Sattva Guna, Vaat-Kapha nature.
Signification: It controls white color, mother, mind, art, white tree, silver, sweet, rice, chest, saliva, lungs and eye sight.

Mars

Nature: It has muscular body, square, cruel, aggressive, man, warrior (Kshatriya) class, Tamo-guni, Fire element, Pitta nature.
Signification: It shows red color, siblings, war, arms, thief, wound, daal, Pitta, blood, muscles, operation, ears and nose etc.

Mercury

Nature: It is thin, impotent, business class (Vaishya), neutral planet, Rajoguni, earth element and consists of all three Vaat, Pitta and Kapha natures.
Signification: It indicates green color, grams, mother's brother, mathematics, trade, speech, tongue, voice, sex related diseases, dumbness, laziness and skin diseases.

Jupiter

Nature: heavy fat body, man, Brahmin, pleasant, Sattva Guna, space element and Kapha nature.
Signification: It depicts yellow color, Vedas, religion, devotion, gold, wise, guru, fat, Kapha, swelling, home, education, sun, progeny, marriage and kidney etc.

Venus

Nature: It is beautiful, female, Brahmin, charming, Rajoguni, water element and Kapha nature.
Signification: It signifies white color, beautiful clothes, beauty, wife, love affair, sex, nuptial bliss, poetry, singing, eyes and women etc.

Saturn

Nature: It has black color, strange eyes, thin and tall body, cruel, impotent, Shudra class, vice, Tamoguni, Vaat Kapha nature and air element.
Signification: It shows back color, father's brother, jealousy, roguishness, thief, beasts, servants, age, moles, physical strength, practice of Yoga, luxury, renunciation, service and heart diseases etc.

Rahu & Ketu

Nature: They are Vice planets, Chandaal, Tamoguni, Vaat Pitta nature and impotent.
Signification: Dark smoke-like color, grandfather, grandmother, deception, accident, quarrel, theft, snake, abroad, skin diseases, legs, hunger and difficulty in progress etc.













source :  http://www.astrosage.com