Professor X is a mutant who possesses vast telepathic powers, and is among the strongest and most powerful telepaths in the Marvel Universe. He is able to perceive the thoughts of others or project his own thoughts within a radius of approximately . Xavier's telepathy once covered the entire world; although following this, Magneto altered the Earth's electromagnetic field to restrict Xavier's telepathic range. While not on Earth, Xavier's natural telepathic abilities have reached across space to make universal mental contact with multiple alien races. With extreme effort, he can also greatly extend the range of his telepathy. He can learn foreign languages by reading the language centers of the brain of someone adept, and alternately "teach" languages to others in the same manner. Xavier once trained a new group of mutants mentally, subjectively making them experience months of training together, while only hours passed in the real world.