A conjunction (yuti) occurs when two or more planets sit in the same sign of a birth chart, merging their energies. When Mars, Mercury and Ketu conjoin, the chart blends Mars's energy, courage and the drive to act, Mercury's intellect, speech and commerce, Ketu's detachment, spirituality and liberation. This is a mixed combination, with 1 benefic and 2 malefic planets involved.
How the Planets Interact
Mars and Mercury are hostile; Mars and Ketu are friendly; Mercury and Ketu are neutral. Friendly planets amplify each other's good results, while hostile planets compete for the same space, creating inner tension that the native must consciously balance. The strongest planet in the group, by dignity, tends to dominate the expression of the conjunction.
Combined Effects
Practically, Mars, Mercury and Ketu together colour the affairs of whichever house they occupy with a mix of energy & courage, intellect & analysis, spirituality & moksha. Being a mixed combination, results swing between ease and effort depending on placement.For a precise reading, the sign, house and dignity of each planet in your own chart must be examined together.