Ketu gayatri mantra
OMM ASHVA DHVAJAAYA VIDMAHE
SHUULA HASTAAYA DHIIMAHI
TANNO KETUH PRACHODAYAAT
Ketu moola mantra with beeja syllables
OMM SHRAAM SHRIIM SHRAUM SAH KETAVE NAMAHA
Palasha Pushpa Sankaasham
Taraka Graha Mastakam
Rudram Rudraatmakam Ghoram
Tam Ketum Pranamamyaham
I offer my obeisance to the violent and fearsome Ketu, who is gifted with the strength of Lord Shiva. Resembling in his complexion the flower of a palasa plant, he serves as the head of the stars and planets.