Ketu is the South node of the Moon, the reference point where Sun’s path intersects with that of the Moon. In mythology, it is referred to as the tail of the dragon. It works pretty much like Mars. Ketu is a headless smoky planet associated with illusion, mystery, detachment, liberation, secrets etc. Ketu is malefic in nature. It takes away what Rahu gives. However, its ultimate aim is Moksha or spiritual liberation, and while driving you towards it, it might take away what Rahu gives like material possessions and money. Rahu is the head of the dragon while Ketu is the lower half, none is complete without the other. In a way, both these planets represent unquenchable desires. Ketu is the maker of psychopaths and serial killers but it is also the maker of world famous magicians and investigators. The sign where Ketu is placed at the time of birth is called Ketu sign.
Your fears, phobias and insecurities also depend upon your Ketu sign. For example, when Ketu is in Cancer, you would always remain worried about family while with Ketu in Libra, you would have a fear of losing your partner. With Ketu in Taurus, you would remain concerned about your material security while someone with Ketu in Scorpio would have fear of heights, poison and enemies. Someone with Ketu in Cancer would have a fear of crowded places while someone with Ketu in Sagittarius would have a fear of confined places.
Ketu is also the karaka of confusion. What you feel confused about in life is also governed by the sign in which Ketu is placed. If you have Ketu in Sagittarius, you might remain highly confused concerning studies. If you have Ketu in Libra, you daily struggle to decide upon what to wear today as dressing sense is your biggest source of confusion. Someone with Ketu in Capricorn would always remain confused about their social status while those with Ketu in Pisces remain confused regarding their spiritual beliefs.
Ketu also gives misunderstanding aligned with the sign where it is placed. When Ketu is in Libra, you are likely to misunderstand your partner while with Ketu in Aries; you would mostly misunderstand your own emotions. Those with Ketu in Cancer lack mental peace while Ketu in Leo on the other hand get carried away and trust others easily.
What you prefer to be mysterious about is also governed by the sign where Ketu in placed. With Ketu in Capricorn, you always keep your business plans under wraps while with Ketu in Scorpio, you always keep your research work garbed and nobody knows what you are up to. With Ketu in Aries, you would have a strange and mysterious personality, very difficult to understand while Ketu in Gemini gives a double-faced, identity confusion. Ketu in Cancer on the other hand do not like to talk about their domestic life and possessions.