A method that includes receiving, by a processing device communicatively coupled to one or more sensors residing at or near a downhole end of a drill string, location information from the one or more sensors. The location information includes a location of particles adhered to a wall of a downhole section of a first wellbore. The method also includes determining, by the processing device and based on the location information, a trajectory of a second wellbore configured to intersect the first wellbore at the downhole section of the first wellbore. The method also includes transmitting, by the processing device to a receiver communicatively coupled to the processing device, the trajectory of the second wellbore to an operator or a controller to drill the second wellbore.