Ketu - South node of the Moon

Ketu - South node of the Moon 
Ketu is the descending lunar node. Vipracitti begot one hundred and one sons, through his wife Simhikā, of whom the eldest is Rāhu and the others are the one hundred Ketus.

Ketu can have a tremendous impact on human lives and in some special circumstances it helps one achieve the zenith of fame. Ketu is often depicted with a gem or star on his head signifying a mystery light.

Ketu represents karmic collections both good and bad, spirituality and supernatural influences. Ketu is associated with the Mīna Avatar (Fish Incarnation) of Vishnu.

Ketu signifies the spiritual process of the refinement of materialization to spirit and is considered both malefic and beneficial, as it causes sorrow and loss, and yet at the same time turns the individual to God. In other words, it causes material loss in order to force a more spiritual outlook in the person.

Ketu is a karaka or indicator of intelligence, wisdom, non-attachment, fantasy, penetrating insight, derangement, and psychic abilities.

Ketu is believed to bring prosperity to the devotee’s family, removes the effects of snakebite and illness arising out of poisons. He grants good health, wealth and cattle to his devotees.

He rides on a vulture and carries the club (daṇḍa) while displaying the Abhayā-mudra.

It is associated with a smoky-grey colour and Ketu's gemstone is cat's-eye. Ketu rules number 7 in Indian numerology.

Ketu bīja mantra:

ॐ स्त्रां स्त्रीं स्त्रों सः केतवे नमः

oṁ strāṁ strīṁ stroṁ saḥ ketave namaḥ

Vedic mantra for Ketu:

पलाशपुष्पसंकाशं तारकाग्रहमस्तकम् रौद्रं रौद्रात्मकं घोरं तं केतुं प्रणमाम्यहम्

palāśapuṣpasaṁkāśaṁ tārakāgrahamastakam
raudraṁ raudrātmakaṁ ghoraṁ taṁ ketuṁ praṇamāmyaham

I bow to Ketu, who is as red as the Palāsa Flower, who has for his head the stars and planets, who is the son of Rudra and who is terrible in form.