Sun, Rahu & Ketu
Ravi, the sun, is also called Aditi or Aditya and more commonly Surya. Temples to him are common. They can be recognized by the image of the sun god inside. He is always represented as a male figure in a chariot. In front of him stands his charioteer Aruna, the brother of Garud, and the chariot is drawn by a gigantic horse with six heads. The sungod's enemy is Rahu. He was the only demon who did not run after Vishnu, when the latter took the form of a beautiful woman and cheated the demons out of their share of the ambrosia. Rahu drank a sip of the ambrosia; but before he could swallow it, the sungod brought his act to the notice of Vishnu. Vishnu instantly cut his head off with his flaming discus. The head having sipped the ambrosia became immortal while the trunk remained mortal and rotted. The head pursues the sungod with malignant enmity, trying to swallow him. Every now and then it succeeds in doing so, but as Rahu's head has no trunk, the sun emerges from his throat. This is the explanation given of solar eclipses. Another story is that Rahu swallowed the ambrosia and became wholly immortal. Vishnu's discus when it cut Rahu in two, created two immortal beings. The head is Rahu and the trunk became Ketu. Rahu causes solar eclipses and Ketu, behaving in a similar manner to the moon, causes lunar eclipses.
Moon & Mercury
Soma, the moon, is more commonly called Chandra. He, (the moon is masculine in India just as in Germany) was one of the articles that came out of the ocean when it was churned, just as Laxmi did. Budh or Mercury is said to be the child of Tara, the wife of Brihaspati, by Soma. Tara confessed to her husband her improper conduct and was at once reduced to ashes. Brahmadev afterwards raised her to life and induced Brihaspati to take her back as she had been purified by fire. The ocean from whom Soma had sprung was angry with him, because he had seduced Tara and drove him from heaven ; but Shiva at Parvati's intercession put Soma or Chandra on his own forehead and in this way brought him back to heaven. Shiva's pictures often show the moon in his hair and his sect mark stands for the crescent moon.
Mars & Jupiter
Mangal, the Mars, is considered the son of earth. He is the son of Sarva, the archer, and his wife Vikesi. Puranik literature indentifies Mangal as the progeny of earth and the god of war. Brihaspati, or Jupiter, is said to be the preceptor of the gods.
Shukra or Venus is not a lady in Hindu mythology, but the son of the sage Bhrigu. He is blind of one eye. He was the preceptor of king Bali. When Vishnu took the form of a dwarf and went to Bali's court, Shukra saw through his disguise. He implored king Bali not to promise the dwarf anything. Bali, however, would not heed his advice and ordered his priest to pour out a libation of water to ratify his gift. Shukra contrived to enter the vessel of water and to stop the water from pouring out. Vishnu, however, met this device by putting a straw through the vessel which entered Shukra's eye. The pain was so acute, that Shukra fled from the vessel. The water fell, the gift was ratified and Bali was ruined.
Shani or Saturn is said to have a most evil influence. I have already described how his mere glance burnt off Ganpati's head. His influence on human affairs is most inauspicious. The Marathi phrase "Shani tyachya potat shirala" (Shani has entered his stomach) is equivalent to saying that a man has been utterly ruined.